Nº de abstracts = 45

Modificado em 23 Fevereiro 2012

Effects of combined whole-body vibration and resistance training on muscular strength and bone metabolism in postmenopausal women.

Bemben DA, Palmer IJ, Bemben MG, Knehans AW.: Bone, 2010, 47(3):650-6. Bone Density Research Laboratory, Department of Health and Exercise Science, University of Oklahoma, Norman, OK 73019, USA.

Whole-body vibration (WBV) has been shown to be osteogenic in animal models; however, its application in humans is not clear. The purpose of this study was to examine the effects of an 8-month program involving WBV plus resistance training on bone mineral density (BMD) and bone metabolism in older postmenopausal women. Fifty-five estrogen-deficient postmenopausal women were assigned to a resistance training group (R, n=22), a WBV plus resistance training group (WBVR, n=21), or a control group (CON, n=12). R and WBVR performed upper and lower body resistance exercises 3 days/week at 80% 1 Repetition Maximum (1RM). WBVR received vibration (30-40 Hz, 2-2.8 g) in three different positions preceding the resistance exercises. Daily calcium intake, bone markers (Bone alkaline phosphatase (Bone ALP); C-terminal telopeptide of Type I collagen (CTX), and BMD of the spine, dual femur, forearm, and total body (DXA) were measured at baseline and after the intervention. At baseline, there were no significant group differences in strength, BMD, or bone marker variables. After 8 months of R or WBVR, there were no significant group or time effects in Bone ALP, CTX, or total body, spine, left hip or right trochanter BMD. However, right total hip and right femoral neck BMD significantly (p<0.05) decreased in all groups. A group x time interaction (p<0.05) was detected at radius 33% BMD site, with CON slightly increasing, and WBVR slightly decreasing. R and WBVR significantly (p<0.05) increased 1RM strength for all exercises, while CON generally maintained strength. WBVR had significantly (p<0.05) greater percent increases in muscular strength than R at 4 months for lat pull down, seated row, hip abduction and hip adduction and at 8 months for lat pull down, hip abduction and hip adduction. Bone metabolism in postmenopausal women was not affected by resistance training either with or without WBV. In contrast, the addition of WBV augmented the positive effects of resistance training on muscular strength in these older women.

Decompression illness.

Vann RD, Butler FK, Mitchell SJ, Moon RE.: Lancet, 20110, 377(9760):153-64. Department of Anesthesiology and Center for Hyperbaric Medicine and Environmental Physiology, Duke University Medical Center, Durham, NC, USA.

Decompression illness is caused by intravascular or extravascular bubbles that are formed as a result of reduction in environmental pressure (decompression). The term covers both arterial gas embolism, in which alveolar gas or venous gas emboli (via cardiac shunts or via pulmonary vessels) are introduced into the arterial circulation, and decompression sickness, which is caused by in-situ bubble formation from dissolved inert gas. Both syndromes can occur in divers, compressed air workers, aviators, and astronauts, but arterial gas embolism also arises from iatrogenic causes unrelated to decompression. Risk of decompression illness is affected by immersion, exercise, and heat or cold. Manifestations range from itching and minor pain to neurological symptoms, cardiac collapse, and death. First-aid treatment is 100% oxygen and definitive treatment is recompression to increased pressure, breathing 100% oxygen. Adjunctive treatment, including fluid administration and prophylaxis against venous thromboembolism in paralysed patients, is also recommended. Treatment is, in most cases, effective although residual deficits can remain in serious cases, even after several recompressions.

Fluid balance, thermal stress, and post exercise response in women's Islamic athletic clothing. Davis JK, Bishop PA, Zhang Y, Matt Green J, Casaru C, Orrick KD, Curtner-Smith M, Richardson MT, Schumacker RE

European journal of applied physiology112(2):725-34, 2012 This study examined heat stress, heart rate (HR), fluid balance, micro-environment temperature and humidity with Islamic athletic clothing (IC) compared to traditional soccer uniform (SC). Ratings of perceived exertion (RPE), session RPE (S-RPE), comfort, and cooling response were also examined. Female volunteers (N = 8) completed a treadmill [Formula: see text] test and then, in a randomized, counter-balanced order, two intermittent running bouts (45 min total) in a hot environment (30.0°C WBGT) in IC and SC. Thereafter, participants sat for 40 min in the hot ambient environment. Repeated measures ANOVA revealed significantly greater micro-environment temperature (p = 0.02) (IC 33.3 ± 3.2°C, SC 32.0 ± 2.8°C) and humidity (p = 0.04) (IC 48.4 ± 8.1%, SC 42.9 ± 7.9%) in IC during the exercise trial but no difference in the 40-min recovery period for micro-environment temperature (p = 0.25) or humidity (p = 0.18). No significant difference (p > 0.05) was shown for core temperature (T (rec)) (IC 38.3 ± 0.4°C, SC 38.2 ± 0.4°C), HR (IC l54 ± 28 beats min(-1), SC 151 ± 26 beats min(-1)) or RPE (IC 4.7 ± 2.1, SC 3.8 ± 1.7) during the exercise trial or recovery period. Results from a paired t test revealed a significantly greater (p < 0.05) S-RPE (IC 5.8 ± 1.2, SC 4.3 ± 1.9), sweat loss (IC 1.4 ± 0.4 L h(-1), SC 1.2 ± 0.4 L h(-1)) and greater discomfort during the exercise and recovery period for the IC. IC clothing appears to have no detrimental effects on heat storage or heat strain during exercise or recovery.

The influence of exercise and circadian rhythm of haemoglobin concentration associated changes in plasma volume on the biological passport. Voss SC, Alsayrafi M, Alsowaidi N, Elzain Elgingo M, Bourdon P, Robinson N, Sottas PE, Klodt F, Nonis D, Schumacher YO

British journal of sports medicine 45(15):A7, 2011Dez In the fight against doping in sports, indirect detection methods using Hb and Hct are starting to play a more and more important role. The goal of this investigation was to quantify the changes in PV during a 2 week study of endurance exercise simulating a cycling stage race and to test for PV changes relative to the circadian rhythm of the athlete. 15 endurance trained triathletes and cyclists performed a standardised 3 day taper (no exercise), followed by a 9 day cycling stage race simulation. Hb showed a mean increase of 4% during the 3 day taper period which was caused by a reduction in PV. During the exercise phase Hb dropped by 1.5 g/dl or 11%, which relates to an average expansion of PV by 0.6 l or 16%. The fluctuations in morning PV showed a wide inter-subject variability. The smallest change was 493 ml (10%), which was accompanied with a drop in Hb from 14.8 g/dl to 13.7 g/dl. The largest increase was 1277 ml (or 25%). The corresponding Hb values for this subject dropped from 15.8 g/dl to 13.1 g/dl (figure 2). The Hb concentration of the morning and evening samples showed a mean difference of approximately 0.6 g/dl or 3.7%, which was observed both during the taper (without exercise) and stage race phases. This study showed that exercise induced changes of PV in healthy trained endurance athletes can be up to 1277 ml or 25% when tested at the same time of the day. This fact needs to be considered in the interpretation of blood profiles as this value might even be higher if the test was to be performed at different times of the day. In our study we were able to demonstrate that the circadian rhythm of Hb concentration remains stable even under maximal PV expansion and reaction to exercise. This finding could be implemented in the athlete biological passport model to help reduce the variation of biological markers.

Influence of relative humidity on prolonged exercise capacity in a warm environment. Watson P, Otani H, Maughan RJ

British journal of sports medicine 45(15):A3-4, 2011 dez Major sports championships are often scheduled in warm/dry and warm/humid environments, so it is important to be able to quantify the influence of these environmental extremes on work capacity. The aim of the present study was to examine the influence of relative humidity on endurance exercise performance in a warm environment. Eight male volunteers (mean ± SD age 26 ± 4 years; height 1.80 ± 0.03 m; body mass 72.0 ± 7.0 kg; VO(2)max 4.38 ± 0.65 l/min) performed four cycle exercise trials at 70% maximum oxygen uptake until volitional exhaustion in an environmental chamber maintained at 30.2 ± 0.2°C. Volunteers were tested under four relative humidity (rh) conditions: 24%, 40%, 60% and 80%. Core and weighted mean skin temperature, heart rate, skin blood flow, and cutaneous vascular conductance (CVC) were recorded at rest and at regular intervals during exercise. Mean (SD) time to exhaustion was 68 ± 19, 60 ± 17, 54 ± 17, and 46 ± 14 min at 24, 40, 60, and 80% rh, respectively (P < 0.001); exercise time was significantly less at 60 (P = 0.013) and 80% (P = 0.005) rh than recorded at 24% rh. There were no differences in core temperature (P = 0.480) and heart rate (P = 0.097) between trials. Core temperature at exhaustion was 39.0 ± 0.3°C at 24, 40, and 60% rh and 39.1 ± 0.3°C at 80% rh (P = 0.159). Mean skin temperature at the point of exhaustion was higher at 80% rh than at 24% rh (P < 0.001). Total sweat loss was similar between trials (P = 0.345), but sweating rate was higher at 60 and 80% rh than at 24% rh (P < 0.001). The results suggest that exercise capacity at moderate intensity in a warm environment is progressively impaired as the relative humidity increases. Early fatigue in the higher humidity trials was accompanied by a faster rate of rise in core temperature and a greater weighted mean skin temperature, with no differences in heart rate, skin blood flow or the metabolic response to exercise.

Effects of Polyester Jerseys on Psycho-physiological Responses during Exercise in a Hot and Moist Environment. Gonzales BR, Hagin V, Guillot R, Placet V, Groslambert A

Journal of strength and conditioning research / National Strength & Conditioning Association 25(12):3432-8, 2011, dez 1Laboratory C3S, "Culture, Sport Health and Sports&\rdquo;, University of Franche-Comté, Besançon, France; and 2Laboratory of Applied Mechanics, R.Chaléat Femto-ST, University of Franche-Comté, Besançon, France.

Gonzales, BR, Hagin, V, Guillot, R, Placet, V, and Groslambert, A. Effects of polyester jerseys on psycho-physiological responses during exercise in a hot and moist environment. J Strength Cond Res 25(12): 3432-3438, 2011-With the general acceptance that extreme environments have a detrimental effect on thermoregulation and human performance, the aim of this study was to investigate the influence of 3 polyester jerseys with knits of different sizes on physiological and perceptual responses in trained cyclists during exercise performed in a hot and moist environment. Ten trained male cyclists (mean ± SD, age: 29.1 ± 8 years, height: 177.12 ± 5 cm, body mass: 70.10 ± 6 kg), performed 3 tests of 15 minutes at 150 W on a calibrated home trainer by randomly wearing jerseys with small knits (SK), medium knits, and large knits (LK). While exercising, the jersey and torso skin temperatures, perceived exertion and hotness, and heart rate (HR) were continuously recorded. The major results of this study showed that perceived hotness with LK was significantly lower (p < 0.05) than with SK at minutes 10 (effect size [ES] = 1.18) and 12 (ES = 1.04) of exercise. The torso skin temperature with LK was significantly lower (p < 0.05) than with SK at minute 10 (ES = 0.84) and at minute 14 (ES = 0.81) of exercise, and the LK jersey temperature was significantly lower (p < 0.05) than with SK jerseys at minutes 12 (ES = 0.83) and 14 (ES = 0.90) of exercise. However, no significant difference was found in perceived exertion or HR. These results suggest that the use of polyester jerseys with larger knits could limit the drift of skin temperature and therefore increase the thermal comfort of cyclists during exercise performed in a hot and moist environment. Therefore, coaches are encouraged to take particular care that their athletes wear exercise-appropriate clothing in hot temperatures.

Cold application for neuromuscular recovery following intense lower-body exercise. Pointon M, Duffield R, Cannon J, Marino FE

European journal of applied physiology 111(12):2977-86, 2011, DezExercise and Sports Science Laboratories, School of Human Movement Studies, Charles Sturt University, Panorama Avenue, Bathurst, NSW, 2795, Australia, Este endereço de e-mail está protegido de spam bots, pelo que necessita do Javascript activado para o visualizar .

This study examined the effects of cold therapy (COLD) on recovery of voluntary and evoked contractile properties following high-intensity, muscle-damaging and fatiguing exercise. Ten resistance-trained males performed 6 × 25 maximal concentric/eccentric muscle contractions of the dominant knee extensors (KE) followed by a 20-min recovery (COLD v control) in a randomized cross-over design. Voluntary and evoked neuromuscular properties of the right KE, ratings of perceived muscle soreness (MS) and pain, and blood markers for muscle damage were measured pre- and post-exercise, and immediately post-recovery, 2, 24 and 48-h post-recovery. Exercise resulted in decrements in voluntary and evoked torque, increased MS and elevated muscle damage markers (p  0.05). Activation of right KE decreased post-exercise with increased activation of biceps femoris (BF) (p  0.05). No significant differences were observed between conditions for creatine kinase or asparate aminotransferase (p > 0.05). However, perceptual ratings of pain were significantly (p < 0.05) lower following COLD compared to control. In conclusion, following damage to the contractile apparatus, COLD did not significantly hasten the recovery of peripheral contractile trauma. Despite no beneficial effect of COLD on recovery of MVC, perceptions of pain were reduced following COLD.

Genetic influences in sport and physical performance. Puthucheary Z, Skipworth JR, Rawal J, Loosemore M, Van Someren K, Montgomery HE

.: Sports Medicine, 2011,10 - 41(10):845-59.The common inheritance of approximately 20?000 genes defines each of us as human. However, substantial variation exists between individual human genomes, including 'replication' of gene sequences (copy number variation, tandem repeats), or changes in individual base pairs (mutations if 1% frequency). A vast array of human phenotypes (e.g. muscle strength, skeletal structure, tendon elasticity, and heart and lung size) influences sports performance, each itself the result of a complex interaction between a myriad of anatomical, biochemical and physiological systems. This article discusses the role for genetic influences in influencing sporting performance and injury, offering specific exemplars where these are known. Many of these preferable genotypes are uncommon, and their combination even rarer. In theory, the chances of an individual having a perfect sporting genotype are much lower than 1 in 20 million?-?as the number of associated polymorphisms increase, the odds decrease correspondingly. Many recently discovered polymorphisms that may affect sports performance have been described in animal or other human based models, and have been included in this review if they may apply to athletic populations. Muscle performance is heavily influenced by basal muscle mass and its dynamic response to training. Genetic factors account for approximately 50-80% of inter-individual variation in lean body mass, with impacts detected on both 'training-naive' muscle mass and its growth response. Several cytokines such as interleukin-6 and -15, cilliary neurotrophic factor and insulin-like growth factor (IGF) have myoanabolic effects. Genotype-associated differences in endocrine function, necessary for normal skeletal muscle growth and function, may also be of significance, with complex interactions existing between thyroxine, growth hormone and the downstream regulators of the anabolic pathways (such as IGF-1 and IGF-2). Almost 200 polymorphisms are known to exist in the vitamin D receptor (VDR) gene. VDR genotype is associated with differences in strength in premenopausal women. VDR expression decreases with age and VDR genotype is associated with fat-free mass and strength in elderly men and women. Muscle fibre type determination is complex. Whilst initial composition is likely to be strongly influenced by genetic factors, training has significant effects on fibre shifts. Polymorphisms of the peroxisome proliferator-activated receptor a (PPARa) gene and R577x polymorphism of the ACTN3 gene are both associated with specific fibre compositions. Alterations in cardiac size have been associated with both increased performance and excess cardiovascular mortality. PPARa is a ligand-activated transcription factor that regulates genes involved in fatty acid uptake and oxidation, lipid metabolism and inflammation. Psychology plays an important role in training, competition, tolerance of pain and motivation. However, the role of genetic variation in determining psychological state and responses remains poorly understood; only recently have specific genes been implicated in motivational behaviour and maintenance of exercise. Thyroid hormone receptors exist within the brain and influence both neurogenesis and behaviour. With the current state of knowledge, the field of genetic influences on sports performance remains in its infancy, despite over a decade of research.

Compression garments and exercise: garment considerations, physiology and performance. Macrae BA, Cotter JD, Laing RM.: Sports Medicine,

2011, 10, 41(10):815-43.Compression garments (CGs) provide a means of applying mechanical pressure at the body surface, thereby compressing and perhaps stabilizing/supporting underlying tissue. The body segments compressed and applied pressures ostensibly reflect the purpose of the garment, which is to mitigate exercise-induced discomfort or aid aspects of current or subsequent exercise performance. Potential benefits may be mediated via physical, physiological or psychological effects, although underlying mechanisms are typically not well elucidated. Despite widespread acceptance of CGs by competitive and recreational athletes, convincing scientific evidence supporting ergogenic effects remains somewhat elusive. The literature is fragmented due to great heterogeneity among studies, with variability including the type, duration and intensity of exercise, the measures used as indicators of exercise or recovery performance/physiological function, training status of participants, when the garments were worn and for what duration, the type of garment/body area covered and the applied pressures. Little is known about the adequacy of current sizing systems, pressure variability within and among individuals, maintenance of applied pressures during one wear session or over the life of the garment and, perhaps most importantly, whether any of these actually influence potential compression-associated benefits. During exercise, relatively few ergogenic effects have been demonstrated when wearing CGs. While CGs appear to aid aspects of jump performance in some situations, only limited data are available to indicate positive effects on performance for other forms of exercise. There is some indication for physical and physiological effects, including attenuation of muscle oscillation, improved joint awareness, perfusion augmentation and altered oxygen usage at sub-maximal intensities, but such findings are relatively isolated. Sub-maximal (at matched work loads) and maximal heart rate appears unaffected by CGs. Positive influences on perceptual responses during exercise are limited. During recovery, CGs have had mixed effects on recovery kinetics or subsequent performance. Various power and torque measurements have, on occasions, benefitted from the use of CGs in recovery, but subsequent sprint and agility performance appears no better. Results are inconsistent for post-exercise swelling of limb segments and for clearance of myocellular proteins and metabolites, while effects on plasma concentrations are difficult to interpret. However, there is some evidence for local blood flow augmentation with compression. Ratings of post-exercise muscle soreness are commonly more favourable when CGs are worn, although this is not always so. In general, the effects of CGs on indicators of recovery performance remain inconclusive. More work is needed to form a consensus or mechanistically-insightful interpretation of any demonstrated effects of CGs during exercise, recovery or - perhaps most importantly - fitness development. Limited practical recommendations for athletes can be drawn from the literature at present, although this review may help focus future research towards a position where such recommendations can be made.

Growth hormone abuse and biological passport: is mannan-binding lectin a complementary candidate?

Such-Sanmartín G, Bosch J, Segura J, Gutiérrez-Gallego R.: Clinical journal of sport medicine, 2011, 21(5):441-3. OBJECTIVE: : In the detection of human growth hormone (GH) abuse, the approach based on altered GH-related biomarkers is also being considered with respect to its application within the context of a biological passport. As a potential biomarker, mannan-binding lectin (MBL), which is reported to respond to recombinant GH (rGH) administration, is evaluated here. DESIGN: : Randomized and single blind and approved by the Ethical Committee (Comité Ético de Investigación Clínica-Instituto Municipal de Asistencia Sanitaria). PARTICIPANTS: : One group of 12 male subjects (24.2 ± 2.2 years; 76.1 ± 6.1 kg) was studied. INTERVENTIONS: : Mannan-binding lectin concentration was measured in 12 healthy individuals after subcutaneous daily doses of 6 IU of rGH administration. Mannan-binding lectin serum concentration increased after rGH administration. Mannan-binding lectin concentration increases were observed 48 hours after the first administration and remained elevated for several days after the final dose. MAIN OUTCOME MEASURES: : Mannan-binding lectin concentration increase and elapsed time to recover initial MBL values after the last rGH administration. RESULTS: : Absolute values displayed high interindividual variability, and 1 individual did not show any MBL increase (potential MBL deficiency). Mannan-binding lectin protein showed a clear concentration increase after continued rGH administration, despite the high heterogeneity found between individuals. CONCLUSIONS: : The use of MBL as a complementary GH-related biomarker could be of interest, taking advantage of the high increases (up to 700%) and the relatively slow recovery time.

Incidence of external auditory canal exostoses in competitive surfers in Japan.

Nakanishi H, Tono T, Kawano H.: 2011, 145(1):80-5.

BJECTIVE: The objective of this study was to demonstrate the prevalence and severity of external auditory canal exostoses in a population of competitive surfers in Japan. The authors used a “surfing index,” the product of the period (years) as an active surfer and the frequency (number of surfing days per week), to predict external auditory exostoses formation. STUDY DESIGN: Cross-sectional study. SETTING: A total of 5 surfing competitions that were held in Miyazaki, Japan. MATERIALS AND METHODS: The ear canals of 373 surfers with an average age of 33.1 years (range, 11-80 years) were examined with an otoscope. The severity of exostosis was classified into 4 groups, ranging from grade 0 to 3, according to otoscopic findings. Subjects also completed a questionnaire detailing their surfing habits. RESULTS: There was a 59.8% overall prevalence of exostoses in 373 surfers. The incidences of grade 1, 2, and 3 exostoses were 118 (31.6%), 71 (19.0%), and 34 (9.1%), respectively. The prevalences of grade 2 and 3 exostoses were higher in surfers with a surfing index of more than 20 (P < .0001). CONCLUSIONS: The authors determined that a positive association exists between the surfing index and the severity of exostoses. The findings suggest that it is possible to assume the likelihood of exostosis formation from the surfing index, and this may be of help to spread awareness of exostosis among surfers.

The magnitude of tissue cooling during cryotherapy with varied types of compression.Tomchuk D, Rubley MD, Holcomb WR, Guadagnoli M, Tarno JM.: Journal of athletic training, 2010 May-Jun, 45(3):230-7.

Oxidative stress and inflammatory parameters after an Ironman race.

Pinho, Ricardo A; Silva, Luciano A; Pinho, Cleber A; Scheffer, Débora L; Souza, Cláudio Benetti, Magnus; Carvalho, Tales; Dal-Pizzol, Felipe: Clinical Journal of Sport Medicine, 2010, 20(4):306-11, Exercise Biochemistry and Physiology Laboratory, Postgraduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciúma, Santa Catarina, Brazil.

OBJECTIVE: The aim of the present study was to investigate oxidative stress markers and inflammatory response in triathletes after an Ironman race (IR). DESIGN: Descriptive research. PARTICIPANTS: Eighteen well-trained male triathletes (mean age, 34.7 +/- 2.15 years; weight, 69.3 +/- 1.9 kg; height, 1.81 +/- 0.58 cm) participated in the study. SETTING: Ironman Triathlon (3.8-km swim, 180-km cycle, 42.2-km run). Mean environmental conditions ranged from 20 to 25 degrees C and from 79% to 85% relative humidity. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Before the race and up to 20 minutes after completing the full race, the weights and heights of volunteers were measured and a 10 mL blood sample was drawn from an antecubital vein. Aliquots of washed/lysed red blood cells and plasma/serum samples were stored at -80 degrees C. Lipid peroxidation, protein carbonylation, superoxide dismutase and catalase activities, and cytokines levels [tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-6, IL-10, and IL-1ra] were determined. RESULTS: After the IR, the results showed a significant increase in TBARS levels (prerace = 1.15 +/- 0.11; postrace = 1.98 +/- 0.27), lipid hydroperoxide content (prerace = 0.75 +/- 0.03; postrace = 1.46 +/- 0.18), protein carbonylation (prerace = 0.67 +/- 0.12; postrace = 2 0.15 +/- 0.60), superoxide dismutase (prerace = 2.67 +/- 0.62; postrace = 3.97 +/- 1.48), and catalase (prerace = 1.48 +/- 0.18; postrace = 2.84 +/- 0.39). TNF-alpha, IL-6, and IL-10 were not detected at basal conditions, but all markers were significantly increased after the IR (TNF-alpha: prerace = ND and postrace = 67.47 +/- 10.34; IL-6: prerace = ND and postrace = 55.41 +/- 3.45; IL-10: prerace = ND and postrace = 122.53 +/- 9.69; IL-1ra: prerace = 127.79 +/- 25.65 and postrace = 259.51 +/- 32.9). CONCLUSIONS: An Ironman race provokes significant alterations in oxidative stress and inflammatory parameters. Thus, more studies with other markers and different designs are needed to elucidate the cellular alterations induced by an IR.

Platelet-rich plasma in muscle healing

Borrione, Paolo; Gianfrancesco, Alessia Di; Pereira, Maria Teresa; Pigozzi, Fabio: American journal of physical medicine & rehabilitation / Association of Academic Physiatrists, 2010, 89(10):854-61. Department of Health Sciences, University of Rome "Foro Italico," Italy.

The muscle healing process is defined as a complex and dynamic process resulting in the restoration of anatomic continuity and function. This process is characterized by a cascade of events triggered by the tissue injury itself. It is widely accepted that growth factors play a central role in the healing processes by modulating the recruitment, duplication, activation, and differentiation of different cell types. This observation is the basis on which the use of platelet-rich plasma in several circumstances is founded; all of them requiring the activation or the modulation of the tissue repair process. There is an extensive documentation of in vitro and in vivo studies demonstrating the safety and efficacy of growth factors in the muscle healing process. Unfortunately, the precise biological efficacy and the lack of long-term side effects have not been clearly demonstrated. With regard to sports medicine, doping-related issues are still a matter of debate, especially regarding the treatment of muscle injuries. The purpose of this review is to examine the role of growth factors during muscle healing processes and to discuss the implications of platelet-rich plasma in its therapeutic applications. Sports medicine issues are also discussed particularly with regard to antidoping regulations.

The effect of exercise on innate mucosal immunity.

N P West, D B Pyne, J M Kyd, G M Renshaw, P A Fricker, A W Cripps.: British Journal of Sports Medicine, 2010, 44(4):227-31. Department of Physiology, Australian Institute of Sport, Canberra, Australia.

METHODS: The authors conducted a prospective observational study comparing salivary lactoferrin and lysozyme concentration over 5 months (chronic changes) in elite rowers (n=17, mean age 24.3+/-4.0 years) with sedentary individuals (controls) (n=18, mean age=27.2+/-7.1 years) and a graded exercise test to exhaustion (acute changes) with a cohort of elite rowers (n=11, mean age 24.7+/-4.1). RESULTS: Magnitudes of differences and changes were interpreted as a standardised (Cohen's) effect size (ES). Lactoferrin concentration in the observational study was approximately 60% lower in rowers than control subjects at baseline (7.9+/-1.2 microg/ml mean+/-SEM, 19.4+/-5.6 microg/ml, p=0.05, ES=0.68, 'moderate') and at the midpoint of the season (6.4+/-1.4 microg/ml mean +/- SEM, 21.5+/-4.2 microg/ml, p=0.001, ES=0.89, 'moderate'). The concentration of lactoferrin at the end of the study was not statistically significant (p=0.1) between the groups. There was no significant difference between rowers and control subjects in lysozyme concentration during the study. There was a 50% increase in the concentration of lactoferrin (p=0.05, ES=1.04, 'moderate') and a 55% increase in lysozyme (p=0.01, ES=3.0, 'very large') from pre-exercise to exhaustion in the graded exercise session. CONCLUSION: Lower concentrations of these proteins may be indicative of an impairment of innate protection of the upper respiratory tract. Increased salivary lactoferrin and lysozyme concentration following exhaustive exercise may be due to a transient activation response that increases protection in the immediate postexercise period.

Effects of different shoe-lacing patterns on dorsal pressure distribution during running and perceived comfort.

Hagen M, Hömme AK, Umlauf T, Hennig EM.: Research in sports medicine (Print), 2010, 18(3):176-87. Biomechanics Laboratory, Department of Sport and Movement Sciences, University of Duisburg-Essen, 45141 Essen, Germany.

The purpose of this study was to investigate the effects of four lacing patterns (one regular, one tight, and two seven-eyelet lacings) on dorsal foot pressures during running and the perception of comfort and stability with 14 male rearfoot runners. By using a pressure insole, peak dorsal pressures were measured under the shoe's tongue. Highest peak pressures were found above the talus, the navicular bone, and the first ray. Seven-eyelet lacings showed a significant enhancement of perceived stability without differences in perceived comfort compared with a regular six-eyelet technique. Reduction of pressure on the talus, the navicular bone, and the extensor tendons is related to better comfort. With individually chosen special seven-eyelet lacings runners can improve foot-shoe coupling without increasing peak dorsal pressures on the tarsus. Knowledge of the location of the dorsal pressure distribution is useful for new tongue and lacing constructions to improve comfort in running shoes while maintaining stability.

A three-year prospective study of illness in professional soccer players.

Orhant E, Carling C, Cox A.: Research in sports medicine (Print), 201007 18(3):199-204. LOSC Lille Métropole Football Club, Camphin-en-Pévèle 59780, France.

The aim of this study was to investigate rates and patterns of illness in professional soccer and their impact on playing resources. Illnesses were prospectively diagnosed over three seasons in first-team professional soccer players (n = 81) by the club's physician. A total of 203 illnesses were diagnosed with a mean of 2.5 +/- 0.7 complaints per player per season. The majority of complaints were classed as upper respiratory (74.5%) and gastrointestinal illnesses (13.7%). Of all illness episodes, 19.7% required a lay-off (mean duration: 2.1 days). Per season, 0.3% +/- 0.01 of all working days were lost due to illness; each player lost an average of 1.1 +/- 0.1 working days and missed 0.1 +/- 0.2 matches. Results from this study suggest that common infectious illnesses have little impact on player availability in professional soccer.

Crowd noise as a cue in referee decisions contributes to the home advantage.

Unkelbach C, Memmert D.: Journal of sport & exercise psychology, 2010, 32(4):483-98. Psychologisches Institut, Universität Heidelberg, Heidelberg, Germany.

The home advantage is one of the best established phenomena in sports (Courneya & Carron, 1992), and crowd noise has been suggested as one of its determinants (Nevill & Holder, 1999). However, the psychological processes that mediate crowd noise influence and its contribution to the home advantage are still unclear. We propose that crowd noise correlates with the criteria referees have to judge. As crowd noise is a valid cue, referee decisions are strongly influenced by crowd noise. Yet, when audiences are not impartial, a home advantage arises. Using soccer as an exemplar, we show the relevance of this influence in predicting outcomes of real games via a database analysis. Then we experimentally demonstrate the influence of crowd noise on referees' yellow cards decisions in soccer. Finally, we discuss why the focus on referee decisions is useful, and how more experimental research could benefit investigations of the home advantage.

Whole-Body Cryotherapy in Athletes

Banfi, Giuseppe, Lombardi, Giovann, Colombini, Alessandra, Melegati, Sports Medicine, 2010, 40(6) pp. 509-517(9).

Cold therapy is commonly used as a procedure to relieve pain symptoms, particularly in inflammatory diseases, injuries and overuse symptoms. A peculiar form of cold therapy (or stimulation) was proposed 30 years ago for the treatment of rheumatic diseases. The therapy, called whole-body cryotherapy (WBC), consists of exposure to very cold air that is maintained at −110°C to −140°C in special temperature-controlled cryochambers, generally for 2 minutes. WBC is used to relieve pain and inflammatory symptoms caused by numerous disorders, particularly those associated with rheumatic conditions, and is recommended for the treatment of arthritis, fibromyalgia and ankylosing spondylitis. In sports medicine, WBC has gained wider acceptance as a method to improve recovery from muscle injury. Unfortunately, there are few papers concerning the application of the treatment on athletes. The study of possible enhancement of recovery from injuries and possible modification of physiological parameters, taking into consideration the limits imposed by antidoping rules, is crucial for athletes and sports physicians for judging the real benefits and/or limits of WBC.

According to the available literature, WBC is not harmful or detrimental in healthy subjects. The treatment does not enhance bone marrow production and could reduce the sport-induced haemolysis. WBC induces oxidative stress, but at a low level. Repeated treatments are apparently not able to induce cumulative effects; on the contrary, adaptive changes on antioxidant status are elicited - the adaptation is evident where WBC precedes or accompanies intense training. WBC is not characterized by modifications of immunological markers and leukocytes, and it seems to not be harmful to the immunological system. The WBC effect is probably linked to the modifications of immunological molecules having paracrine effects, and not to systemic immunological functions. In fact, there is an increase in anti-inflammatory cytokine interleukin (IL)-10, and a decrease in proinflammatory cytokine IL-2 and chemokine IL-8. Moreover, the decrease in intercellular adhesion molecule-1 supported the anti-inflammatory response. Lysosomal membranes are stabilized by WBC, reducing potential negative effects on proteins of lysosomal enzymes. The cold stimulation shows positive effects on the muscular enzymes creatine kinase and lactate dehydrogenase, and it should be considered a procedure that facilitates athletes' recovery. Cardiac markers troponin I and high-sensitivity C-reactive protein, parameters linked to damage and necrosis of cardiac muscular tissue, but also to tissue repair, were unchanged, demonstrating that there was no damage, even minimal, in the heart during the treatment. N-Terminal pro B-type natriuretic peptide (NT-proBNP), a parameter linked to heart failure and ventricular power decrease, showed an increase, due to cold stress. However, the NT-proBNP concentrations observed after WBC were lower than those measured after a heavy training session, suggesting that the treatment limits the increase of the parameter that is typical of physical exercise. WBC did not stimulate the pituitary-adrenal cortex axis: the hormonal modifications are linked mainly to the body's adaptation to the stress, shown by an increase of noradrenaline (norepinephrine).

We conclude that WBC is not harmful and does not induce general or specific negative effects in athletes. The treatment does not induce modifications of biochemical and haematological parameters, which could be suspected in athletes who may be cheating. The published data are generally not controversial, but further studies are necessary to confirm the present observations.

Core cooling and thermal responses during whole-head, facial, and dorsal immersion in 17 °C water

Thea Pretorius, Dominique D. Gagnon, and Gordon G. Giesbrecht: Appl. Physiol. Nutr. Metab. 35(5): 627–634 (2010).
Abstract: This study isolated the effects of dorsal, facial, and whole-head immersion in 17 °C water on peripheral vasoconstriction and the rate of body core cooling. Seven male subjects were studied in thermoneutral air (~28 °C). On 3 separate days, they lay prone or supine on a bed with their heads inserted through the side of an adjustable immersion tank. Following 10 min of baseline measurements, the water level was raised such that the water immersed the dorsum, face, or whole head, with the immersion period lasting 60 min. During the first 30 min, the core (esophageal) cooling rate increased from dorsum (0.29 ± 0.2 °C·h^–1) to face (0.47 ± 0.1 °C·h^–1) to whole head (0.69 ± 0.2 °C·h^–1) (p < 0.001); cooling rates were similar during the final 30 min (mean, 0.16 ± 0.1 °C·h^–1). During the first 30 min, fingertip blood flow (laser Doppler flux as percent of baseline) decreased faster in whole-head immersion (114 ± 52%·h^–1) than in either facial (51 ± 47%·h^–1) or dorsal (41 ± 55%·h^–1) immersion (p < 0.03); rates of flow decrease were similar during minutes 30 to 60 (mean, 22.5 ± 19%·h^–1). Total head heat loss over 60 min was significantly different between whole-head (120.5 ± 13 kJ), facial (86.8 ± 17 kJ), and dorsal (46.0 ± 11 kJ) immersion (p < 0.001). The rate of core cooling, relative to head heat loss, was similar in all conditions (mean, 0.0037 ± 0.001 °C·kJ^–1). Although the whole head elicited a higher rate of vasoconstriction, the face did not elicit more vasoconstriction than the dorsum. Rather, the progressive increase in core cooling from dorsal to facial to whole-head immersion simply correlates with increased heat loss.

Palm cooling does not reduce heat strain during exercise in a hot, dry environment

Fabiano T. Amorim, Paulette M. Yamada, Robert A. Robergs, and Suzanne M. Schneider: Appl. Physiol. Nutr. Metab. 35(4): 480–489 (2010)  |

To compare the effectiveness of the rapid thermal exchange device (RTX) in slowing the development of hyperthermia and associated symptoms among hand immersed in water bath (WB), water-perfused vest (WPV), and no cooling condition (NC). Ten subjects performed 4 heat stress trials. The protocol consisted of 2 bouts of treadmill walking, separated by a cooling–rehydration period. The times to reach the predetermined rectal temperature in the first (38.5 °C) and second bouts (39 °C) were not different among RTX, NC, and WB, but was longer for the WPV in both bouts (p < 0.05). Heat storage was significantly lower for WPV only in the first bout vs. the other conditions (p < 0.05). Heart rate (HR) was not different at 10, 20, and 30 min during the first bout among RTX, NC, and WB, but was lower for WPV (p < 0.05). HR was not different among conditions during the second bout. The RTX was not effective in slowing the development of hyperthermia.

Hematological indices, mountain sickness and MRI brain abnormalities in professional and amateur mountain climbers after altitude exposure.

Fayed N, Diaz L, Dávila J, Medrano J.: Neurological Research, 2010, 32(2):144-7. Department of Radiology, Quiron Hospital, Zaragoza, Spain.

The purpose of this work was to correlate the presence of brain abnormalities on magnetic resonance imaging (MRI) with changes in hematological variables and the presence of mountain sickness in 21 mountain climbers involved in two different expeditions to high mountains, Everest and Aconcagua, without supplementary oxygen and recommended acclimatization for this kind of activities. The climbers underwent medical examination, hematological studies, electrocardiogram and MRI of the cerebrum. Wilcoxon signed-rank test was used to evaluate the changes in hematocrit, hemoglobin, red blood cells, iron and ferritin. Mountain sickness was correlated with the age of the climbers and the altitude ascended, final hemoglobin and final mean corpuscular hemoglobin concentration. There were no differences related to conditions of professional or amateur climbers and the changes of those hematological variables, as seen with the nominal regression. We found more brain damage on MRI in amateur than professional climbers. Amateur climbers are more susceptible to suffer acute mountain sickness and permanent cerebral damage than professional climbers after high altitude exposure.

Recreational soccer is an effective health-promoting activity for untrained men.

Krustrup P, Nielsen JJ, Krustrup BR, Christensen JF, Pedersen H, Randers MB, Aagaard P, Petersen AM, Nybo L, Bangsbo J.: British Journal of Sports Medicine, 2009, 43(11):825-31 . University of Copenhagen, Department of Exercise and Sport Sciences, Copenhagen Muscle Research Centre, The August Krogh Building, Universitetsparken 13, Copenhagen 2100-Ø, Denmark.

To examine the effects of regular participation in recreational soccer on health profile, 36 healthy untrained Danish men aged 20-43 years were randomised into a soccer group (SO; n = 13), a running group (RU; n = 12) and a control group (CO; n = 11). Training was performed for 1 h two or three times per week for 12 weeks; at an average heart rate of 82% (SEM 2%) and 82% (1%) of HR(max) for SO and RU, respectively. During the 12 week period, maximal oxygen uptake increased (p<0.05) by 13% (3%) and 8% (3%) in SO and RU, respectively. In SO, systolic and diastolic blood pressure were reduced (p<0.05) from 130 (2) to 122 (2) mm Hg and from 77 (2) to 72 (2) mm Hg, respectively, after 12 weeks, with similar decreases observed for RU. After the 12 weeks of training, fat mass was 3.0% (2.7 (0.6) kg) and 1.8% (1.8 (0.4) kg) lower (p<0.05) for SO and RU, respectively. Only SO had an increase in lean body mass (1.7 (0.4) kg, p<0.05), an increase in lower extremity bone mass (41 (8) g, p<0.05), a decrease in LDL-cholesterol (2.7 (0.2) to 2.3 (0.2) mmol/l; p<0.05) and an increase (p<0.05) in fat oxidation during running at 9.5 km/h. The number of capillaries per muscle fibre was 23% (4%) and 16% (7%) higher (p<0.05) in SO and RU, respectively, after 12 weeks. No changes in any of the measured variables were observed for CO. In conclusion, participation in regular recreational soccer training, organised as small-sided drills, has significant beneficial effects on health profile and physical capacity for untrained men, and in some aspects it is superior to frequent moderate-intensity running.

Heat illness among high school athletes --- United States, 2005-2009.

MMWR. Morbidity and Mortality Weekly Report, 2010, 59(32):1009-13 .

Heat illness during practice or competition is a leading cause of death and disability among U.S. high school athletes. An estimated 7.5 million students participate in high school Sports annually. To examine the incidence and characteristics of heat illness among high school athletes, CDC analyzed data from the National High School Sports-Related Injury Surveillance Study for the period 2005-2009, which includes the 2005-06, 2006-07, 2007-08 and 2008-09 school years. During 2005-2009, the 100 schools sampled reported a total of 118 heat illnesses among high school athletes resulting in >or=1 days of time lost from athletic activity (i.e., time-loss heat illness), a rate of 1.6 per 100,000 athlete-exposures and an average of 29.5 time-loss heat illnesses per school year. The average corresponds to a weighted average annual estimate of 9,237 illnesses nationwide. The highest rate of time-loss heat illness was among football players, 4.5 per 100,000 athlete-exposures, a rate 10 times higher than the average rate (0.4) for the eight other Sports. Time-loss heat illnesses occurred most frequently during August (66.3%) and while practicing or playing football (70.7%). No deaths were reported. Consistent with guidelines from the National Athletic Trainers' Association (NATA), to reduce the risk for heat illness, high school athletic programs should implement heat-acclimatization guidelines (e.g., set limits on summer practice duration and intensity). All athletes, coaches, athletic trainers, and parents/guardians should be aware of the risk factors for heat illness, follow recommended strategies, and be prepared to respond quickly to symptoms of illness. Coaches also should continue to stress to their athletes the importance of maintaining proper hydration before, during, and after Sports activities.

The science of sex verification and athletic performance.

Tucker R, Collins M.: International Journal of Sports Physiology and Performance, 2010, 5(2):127-39. UCT/MRC Research Unit for Exercise Science and Sports Medicine of the Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.

The division of athletes into male and female categories for competition is a widely accepted practice and is ordinarily straightforward, requiring no intervention from authorities. However, for reasons ranging from deliberate cheating to complex medical conditions resulting in ambiguous development of sex organs, the controversy of sex verification in athletic events has existed for 70 years. Testing procedures, initially implemented to prevent cheating by men masquerading as women, have produced humiliating outcomes for women athletes who were often for the first time confronted with the possibility that they have one of the disorders of sex development. Sporting authorities have and continue to formulate position stands for the management of such cases. An important missing component in this debate is the sound scientific evidence to determine (a) whether a performance advantage actually exists and (b) how large it might be. The division of competition into separate categories and the large difference in sporting performance between male and female necessitate that sport-governing bodies define the boundaries between the sexes in a just and fair manner for all participating athletes. This review will therefore provide the historical context of the debate and aim to discuss relevant physiological and performance aspects of the sex verification process.

Non-steroidal anti-inflammatory drugs for athletes: an update.

Ziltener JL, Leal S, Fournier PE.: Annals of Physical and Rehabilitation Medicine, 2010, 53(4):278-82, 282-8 . Unité orthopédie et traumatologie du sport, département de chirurgie, hôpitaux universitaires de Genève, 1211 Genève, Switzerland.

Sports medicine physicians often treat athletes in pain with non-steroidal anti-inflammatory drugs (NSAIDs). However, there is a lack of high-quality evidence to guide NSAID use. Their adverse effects have clinical relevance, and their possible negative consequences on the long-term healing process are slowly becoming more obvious. This article provides some practical management guidelines for the use of NSAIDs, developed to help Sports medicine physicians deal with frequent Sports-related injuries. We do not recommend their use for muscle injuries, bone fractures (also stress fractures) or chronic tendinopathy. In all cases, if chosen, NSAID treatments should always be kept as short as possible and should take into account the specific type of injury, the level of dysfunction and pain.

Non-steroidal anti-inflammatory drugs in Sports medicine: guidelines for practical but sensible use.

Paoloni JA, Milne C, Orchard J, Hamilton B. British Journal of Sports Medicine, 2009, 43(11):863-5 . Aspetar, Qatar Orthopaedic and Sports Medicine Hospital, PO Box 29222, Doha, Qatar.

Introduction: Non-steroidal anti-inflammatory drugs (NSAID) are commonly used in Sports medicine. NSAID have known anti-inflammatory, analgesic, antipyretic and antithrombotic effects, although their in-vivo effects in treating musculoskeletal injuries in humans remain largely unknown. NSAID analgesic action is not significantly greater than paracetamol for musculoskeletal injury but they have a higher risk profile, with side-effects including asthma exacerbation, gastrointestinal and renal side-effects, hypertension and other cardiovascular diseases. Discusssion: The authors recommend an approach to NSAID use in Sports medicine whereby simple analgesia is preferentially used when analgesia is the primary desired outcome. However, based both on the current pathophysiological understanding of most injury presentations and the frequency that inflammation may actually be a component of the injury complex, it is premature to suppose that NSAID are not useful to the physician managing Sports injuries. The prescribing of NSAID should be cautious and both situation and pathology specific. Both dose and duration minimisation should be prioritized and combined with simple principles of protection, rest, ice, compression, elevation (PRICE), which should allow NSAID-sparing. NSAID use should always be coupled with appropriate physical rehabilitation. Conclusion: NSAID are probably most useful for treating nerve and soft-tissue impingements, inflammatory arthropathies and tenosynovitis. They are not generally indicated for isolated chronic tendinopathy, or for fractures. The use of NSAID in treating muscle injury is controversial. Conditions in which NSAID use requires more careful assessment include ligament injury, joint injury, osteoarthritis, haematoma and postoperatively.

Differential diagnostics of the musculoskeletal system in Sports medicine

Nehrer S, Der Radiologe, 2010, 50(5):427-34 . Department für Klinische Medizin und Biotechnologie, Zentrum für Regenerative Medizin, Donau-Universität Krems, Dr.-Karl-Dorrek-Str. 30, A-3500, Krems, Osterreich.

The positive effects of Sports on the cardiovascular and musculoskeleal systems are widely accepted. Nevertheless, Sports also can cause injury and overuse leading to sport-specific problems, which are often a challenge in diagnosing and treatment. The history of the sport-related injury is crucial for further differential diagnosis. Careful inspection, palpation and functional testing can reveal the possible pathology and lead to an effective strategy in the diagnostic assessment using radiographic tools such as sonography, X-ray and MR imaging (MRI). In muscle and tendon injuries sonography can provide ready to use information concerning muscle tears and tendon ruptures or degenerative lesions. Plain X-rays give a good overview on joint conditions regarding the bone and sometimes have to be completed by focused enlargement of the critical structure, especially in stress fractures and small bone lesions. MRT is the gold standard in the evaluation of interarticular and extra-articular sport-related pathologies, however, an exact clinical diagnosis allows a more effective investigation protocol. Profound knowledge of possible sport-specific injury and overuse patterns is necessary to detect lesions of the musculoskeletal system in active athletes and to use the fitting radiographic strategy for confirmation. The exact diagnosis is the prerequisite for initiating the appropriate treatment and a fast Sports medical rehabilitation process.

A day trip to a forest park increases human natural killer activity and the expression of anti-cancer proteins in male subjects.

Li Q, Kobayashi M, Inagaki H, Hirata Y, Li YJ, Hirata K, Shimizu T, Suzuki H, Katsumata M, Wakayama Y, Kawada T, Ohira T, Matsui N, Kagawa T.: Journal of Biological Regulators and Homeostatic Agents, 2010, 24(2):157-65. Department of Hygiene and Public Health, Nippon Medical School, Bunkyo-ku, Tokyo, Japan.

We previously reported that 2-night/3-day trips to forest parks enhanced human NK activity, the number of NK cells, and intracellular anti-cancer proteins in lymphocytes, and that this increased NK activity lasted for more than 7 days after the trip in both male and female subjects. In the present study, we investigated the effect of a day trip to a forest park on human NK activity in male subjects. Twelve healthy male subjects, aged 35-53 years, were selected after giving informed consent. The subjects experienced a day trip to a forest park in the suburbs of Tokyo. They walked for two hours in the morning and afternoon, respectively, in the forest park on Sunday. Blood and urine were sampled in the morning of the following day and 7 days after the trip, and the NK activity, numbers of NK and T cells, and granulysin, perforin, and granzyme A/B-expressing lymphocytes, the concentration of cortisol in blood samples, and the concentration of adrenaline in urine were measured. Similar measurements were made before the trip on a weekend day as the control. Phytoncide concentrations in the forest were measured. The day trip to the forest park significantly increased NK activity and the numbers of CD16(+) and CD56(+) NK cells, perforin, granulysin, and granzyme A/B-expressing NK cells and significantly decreased CD4(+) T cells, the concentrations of cortisol in the blood and adrenaline in urine. The increased NK activity lasted for 7 days after the trip. Phytoncides, such as isoprene, alpha-pinene, and beta-pinene, were detected in the forest air. These findings indicate that the day trip to the forest park also increased the NK activity, number of NK cells, and levels of intracellular anti-cancer proteins, and that this effect lasted for at least 7 days after the trip. Phytoncides released from trees and decreased stress hormone levels may partially contribute to the increased NK activity.

Effect of hot versus cold climates on power output, muscle activation, and perceived fatigue during a dynamic 100-km cycling trial.

Abbiss CR, Burnett A, Nosaka K, Green JP, Foster JK, Laursen PB. Journal of Sports Sciences, 2010, 28(2):117-25 . School of Exercise, Biomedical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia.

The Purpose of this study was to examine the influence of environmental temperature on power output, muscle activation, body temperature, and perceived physical strain during a dynamic self-paced 100-km cycling trial. Nine endurance-trained male cyclists (mean + or - s: age 31 + or - 6 years; VO(2max) 62.1 + or - 8.5 ml x kg(-1) x min(-1)) completed two 100-km experimental trials, interspersed with five 1-km and four 4-km high-intensity epochs, in hot (34 degrees C) and cold (10 degrees C) environments. Measurements consisted of power output, rectal and skin temperature, muscle activation of vastus lateralis, biceps femoris and soleus, ratings of perceived exertion, thermal sensation and pain intensity in the quadriceps. Power output and muscle activation of the biceps femoris and soleus were lower in the hot trial (22 km; P < 0.05) prior to significant (P < 0.05) differences in rectal temperature [38.8 degrees C (cold) vs. 39.1 degrees C (hot)] at 42 km. Muscle activation of the vastus lateralis, biceps femoris, and soleus was significantly (P 0.68) but not with perceived pain or exertion. Thus, a hyperthermic-induced anticipatory reduction of muscle activation may have occurred during the hot exercise trials only. Fatigue and pacing during prolonged dynamic exercise in the cold appears to be influenced by factors dissociated from hyperthermic-induced stress.

Playing field issues in Sports medicine.

Wright JM, Webner D.: Current Sports Medicine Reports, 2010, 9(3):129-33 .Crozer-Keystone Health System, Springfield, PA 19064, USA.

The use of artificial turf on playing fields has increased in popularity. Advances in technology have allowed for the development of turf that closely mimics the properties of natural grass. Overall injury incidence does not differ between the two surfaces, but unique injury patterns are apparent between the two surfaces. Differences in shoe-surface interface, in-shoe foot loading patterns, and impact attenuation may provide insight into the different injury patterns. Player perceptions of artificial turf vary and may be related to different physiological demands between the two surfaces. Artificial turf has been implicated in skin infections, but concerns about other health consequences related to the synthetic materials have not been proven yet. Understanding the differences between artificial turf and natural grass will help physicians, athletic trainers, and coaches better care for and train their athletes.

Going the extra mile: health care for marathon runners.

Doherty L.: Emergency nurse : the journal of the RCN Accident and Emergency Nursing Association

201005 18(2):18-20.

At last year's London Marathon, St John Ambulance (SJA) volunteers treated almost 6,200 casualties from among more than 35,000 runners. In this article, emergency nurse Hazel Mortimer, who regularly works as a volunteer emergency nurse with the SJA, describes her experiences at this year's event and her expectations of the 2012 Olympics.

Analgesics and anti-inflammatory medications in sports: use and abuse.

Feucht CL, Patel DR.: Pediatric Clinics of North Americam, 2010-06 57(3):751-74. Department of Pharmacy Practice, Ferris State University, Kalamazoo, MI, USA.

Both acute and overuse musculoskeletal injuries are common in adolescent athletes. Pharmacologic agents including nonsteroidal anti-inflammatory drugs, acetaminophen, and topical over-the-counter agents have been shown to be effective in controlling pain, but data regarding their efficacy in expediting healing and time to recovery continue to be debated. Studies indicate that adolescents consume analgesic agents on their own and may be unaware of their potential toxicities. Data also indicate that adolescent athletes use medications in hopes of alleviating pain and allowing continuation of sports without adequate time for healing. This article reviews the mechanisms, toxicity, drug interactions, efficacy, and abuse potential of commonly used analgesic and anti-inflammatory drugs.

Fatigue management in the preparation of Olympic athletes.

Robson-Ansley PJ, Gleeson M, Ansley L.: Journal of Sports Sciences, 2009-11 27(13):1409-20.

Fatigue is often a consequence of physical training and the effective management of fatigue by the coach and athlete is essential in optimizing adaptation and performance. In this paper, we explore a range of practical and contemporary methods of fatigue management for Olympic athletes. We assesses the scientific merit of methods for monitoring fatigue, including self-assessment of training load, self-scored questionnaires, and the usefulness of saliva and blood diagnostic markers for indicating fatigued and under-recovered athletes, effective nutrition and hydration strategies for optimizing recovery and short-term recovery methods. We conclude that well-accepted methods such as sufficient nutrition, hydration, and rest appear to be the most effective strategies for optimizing recovery in Olympic athletes.

Medical and orthopedic conditions and sports participation.

Diokno E, Rowe D.: Pediatric Vlinics of North America, 2010-06 57(3):839-47, Arnold Palmer Sports Health Center, Union Memorial Hospital, Baltimore, MD 21218, USA.

The presence of certain medical or orthopedic conditions need not preclude adolescents from being physically active and participating in sports. The benefits of continued physical activity far outweigh any concerns for potential complications for most such conditions. This article reviews sport participation guidelines for adolescents with conditions that include juvenile chronic arthritis, eye injures, solitary kidney, skin conditions, scoliosis, and spondylolysis.

Sport participation by physically and cognitively challenged young athletes.

Patel DR, Greydanus DE.: Pediatric Clinics of North America, 2010-06 57(3):795-817. Department of Pediatrics and Human Development, Michigan State University College of Human Medicine, Kalamazoo, MI 49008, USA.

Many physically and cognitively challenged athletes participate in organized and recreational sports. Health benefits of sport participation by athletes with disabilities have been well recognized. A careful preparticipation evaluation and proper classification of athletes ensures safe sports participation by athletes with disabilities. Some conditions in these athletes, such as problems with thermoregulation, autonomic control, neurogenic bladder and bowel, latex allergy, and many associated and secondary complications deserve special consideration. This article reviews common medical issues that relate to sport participation by athletes with physical and cognitive disabilities.

Serum chemistry test and urinalysis parameter analysis in half marathon athletes.

Siqueira Lde O, Muccini T, Dall Agnol I, Filla L, Tibbola P, Luvison A, Costa L, Moreira JC.: Arquivos Brasileiros de Endocrinologia e Metabologia, 2009, 53(7):844-52. Curso de Farmácia, Instituto de Ciências Biológicas, Universidade de Passo Fundo, Passo Fundo, RS, Brasil.

OBJECTIVE: The aim of this study was to analyze biochemical markers as indicators of athletic performance, in light of a clinical context and athletic. METHODS: Samples of peripheral blood (8 mL) and urine (50 mL) were collected from 20 marathon athletes at rest and 15 minutes after half marathon. Following, examination of blood, urine and serum markers of renal function, muscle damage and lipidic profile was carried out. RESULTS: Statistical analysis of the results showed a significant increase (p < 0.05) in serum activity of the enzymes CK, CK-MM, CK-MB and LDH, serum creatinine and iron, leukocyte count and neutrophils. Furthermore, triglycerides, VLDL, uric acid in serum showed a significant decrease. CONCLUSION: This study shows that athletes of marathon show changes in biochemical parameters of blood and urine after competing in this modality, which demonstrates the importance of carrying out laboratory tests as diagnosis for silent biochemical disorders.

Exostoses of the external auditory canal in white-water kayakers.

Moore RD, Schuman TA, Scott TA, Mann SE, Davidson MA, Labadie RF.: The Laryngoscope, 2010, 120(3):582-90. Department of Otolaryngology-Head and Neck Surgery, and Vanderbilt University School of Medicine, Nashville, Tennessee 37232-8605, USA.

Objectives / Hyporthesis/: Exostoses of the external auditory canal are benign bony tumors associated with frequent cold-water exposure. Obstruction may lead to conductive hearing loss and recurrent otitis externa, requiring surgical correction when symptoms become intolerable. This study aimed to characterize the prevalence of exostoses in white-water kayakers and identify associated risk factors and protective measures. Study design: Cross-sectional. Methods: Six hundred eleven white-water kayakers from across the United States were included in the study. Percent occlusion was graded as minimal (75%). Subjects completed a survey of risk factors and protective measures. Kruskal-Wallis and chi(2) tests were performed to determine significant associations with percent occlusion. A multivariate proportional odds regression model was fit to adjust for confounding between the variables. Results: The prevalence of exostoses in kayakers was 79% (482/611); 13% (78/611) had >or=75% occlusion. Percent occlusion was associated with total years kayaked (P or=1 day/week (P < .001), male gender (P < .001), and increasing age (P = .005), although frequency, gender, and age were confounded by total years. Styles that involve repeated submersion were also associated with greater occlusion (freestyle, P = .036; squirt, P = .016). Subjects who used earplugs for a greater proportion of their kayaking career were less likely to have exostoses (P < .001). When adjusted for confounding, only total years (P = .0003) and age (P = .0027) remained significant. Conclusions: Kayakers are the first inland population to experience exostoses at the rates seen in coastal populations (e.g., surfers). When used long-term, earplugs may be protective.

Laterality of exostosis in surfers due to evaporative cooling effect.

King JF, Kinney AC, Iacobellis SF, Alexander TH, Harris JP, Torre P, Doherty JK, Nguyen QT.: Otology & neurotology, 2010 31(2):345-51. Division of Otolaryngology-Head and Neck Surgery, University of California San Diego, La Jolla, California 92103, USA.

Objectives: 1. To correlate exostosis severity with ear canal evaporative cooling. 2. To assess hearing and complications after canalplasty. Study design: Retrospective chart review. Sibjects and Method: A retrospective chart review from 1990 to 2007 at a university tertiary referral center. Results: Surfers from the west coast of the United States were twice as likely to have severe exostoses in the right ear compared with the left. Evaporative cooling from a predominant northerly wind direction during the coldest water temperature months in this region may contribute to this lateral bias because surfers on this coast spend most of their time facing west. Few postoperative complications were identified. No cases of facial nerve injury or entry into the temporomandibular joint occurred. Differences in preoperative versus postoperative pure-tone hearing thresholds were not significant. Conclusion: Exostosis severity seems to correspond to the ear that is more exposed to the predominant coastal wind. We propose that evaporative cooling in a cold water environment contributes to greater progression of exostoses in the ear with more exposure to the predominant wind. Exostosis removal using the postauricular approach carries a low complication rate.

Combining hypoxic methods for peak performance.

Millet GP, Roels B, Schmitt L, Woorons X, Richalet JP.: Sports medicine (Auckland, N.Z.), 2010 40(1):1-25. Institute of Sport Science, University of Lausanne, Lausanne, Switzerland.

New methods and devices for pursuing performance enhancement through altitude training were developed in Scandinavia and the USA in the early 1990s. At present, several forms of hypoxic training and/or altitude exposure exist: traditional 'live high-train high' (LHTH), contemporary 'live high-train low' (LHTL), intermittent hypoxic exposure during rest (IHE) and intermittent hypoxic exposure during continuous session (IHT). Although substantial differences exist between these methods of hypoxic training and/or exposure, all have the same goal: to induce an improvement in athletic performance at sea level. They are also used for preparation for competition at altitude and/or for the acclimatization of mountaineers. The underlying mechanisms behind the effects of hypoxic training are widely debated. Although the popular view is that altitude training may lead to an increase in haematological capacity, this may not be the main, or the only, factor involved in the improvement of performance. Other central (such as ventilatory, haemodynamic or neural adaptation) or peripheral (such as muscle buffering capacity or economy) factors play an important role. LHTL was shown to be an efficient method. The optimal altitude for living high has been defined as being 2200-2500 m to provide an optimal erythropoietic effect and up to 3100 m for non-haematological parameters. The optimal duration at altitude appears to be 4 weeks for inducing accelerated erythropoiesis whereas <3 weeks (i.e. 18 days) are long enough for beneficial changes in economy, muscle buffering capacity, the hypoxic ventilatory response or Na(+)/K(+)-ATPase activity. One critical point is the daily dose of altitude. A natural altitude of 2500 m for 20-22 h/day (in fact, travelling down to the valley only for training) appears sufficient to increase erythropoiesis and improve sea-level performance. 'Longer is better' as regards haematological changes since additional benefits have been shown as hypoxic exposure increases beyond 16 h/day. The minimum daily dose for stimulating erythropoiesis seems to be 12 h/day. For non-haematological changes, the implementation of a much shorter duration of exposure seems possible. Athletes could take advantage of IHT, which seems more beneficial than IHE in performance enhancement. The intensity of hypoxic exercise might play a role on adaptations at the molecular level in skeletal muscle tissue. There is clear evidence that intense exercise at high altitude stimulates to a greater extent muscle adaptations for both aerobic and anaerobic exercises and limits the decrease in power. So although IHT induces no increase in VO(2max) due to the low 'altitude dose', improvement in athletic performance is likely to happen with high-intensity exercise (i.e. above the ventilatory threshold) due to an increase in mitochondrial efficiency and pH/lactate regulation. We propose a new combination of hypoxic method (which we suggest naming Living High-Training Low and High, interspersed; LHTLHi) combining LHTL (five nights at 3000 m and two nights at sea level) with training at sea level except for a few (2.3 per week) IHT sessions of supra-threshold training. This review also provides a rationale on how to combine the different hypoxic methods and suggests advances in both their implementation and their periodization during the yearly training programme of athletes competing in endurance, glycolytic or intermittent sports.

Bone volumetric density, geometry, and strength in female and male collegiate runners.

Smock AJ, Hughes JM, Popp KL, Wetzsteon RJ, Stovitz SD, Kaufman BC, Kurzer MS, Petit MA.: Medicine and Science in Sports and Exercise, 2009, 41(11):2026-32. School of Kinesiology, Laboratory of Musculoskeletal Health, University of Minnesota, Minneapolis, MN 55455, USA.

Purpose: To explore differences in tibial bone geometry, volumetric density, and estimates of bone strength in runners and healthy controls. Methods: Male (n = 21) and female (n = 38) runners (49.1 +/- 13.2 miles x wk(-1)) and inactive healthy controls (17 males and 32 females; mean age = 22 +/- 3.3 yr) were recruited to participate. Peripheral quantitative computed tomography was used to assess total volumetric bone mineral density (vBMD, mg x mm(-3)), total bone area (ToA, mm2), and an estimate of compressive bone strength (bone strength index (BSI) = ToA x total bone volumetric density (ToD2)) at the distal (4%) site of the tibia. ToA (mm2) and cortical bone area (CoA, mm2), cortical vBMD (CoD, mg x mm(-3)), cortical thickness (CoTh, mm), and an estimate of bone bending strength (polar strength strain index (SSIp), mm3) were measured at 50% and 66% sites. Results: ToA and BSI were significantly greater (+11%-19%, P < 0.05) in female runners than controls at the 4% site. At the proximal sites, female runners had significantly greater ToA, CoA, CoTh, and SSIp (+9%-19%, all P < 0.001) compared with female controls. vBMD was similar at all tibia sites. Compared with controls, male runners had significantly greater CoTh at the 50% and 66% sites (+8% and 14%, respectively, P < 0.05) as well as greater CoA (+11%, P < 0.009) at the 66% site. There were no differences in bone strength or density at any site in the male runners. Conclusions: Greater bone strength in female runners was attributable to greater bone area rather than density. Although male runners did not show greater bone strength, they did exhibit favorable bone geometric properties. These data further document that running has osteogenic potential.

Non-steroidal anti-inflammatory drugs in sports medicine: guidelines for practical but sensible use

J A Paoloni, C Milne, J Orchard, B Hamilton: Br J Sports Med 2009;43:863-865.

Introduction: Non-steroidal anti-inflammatory drugs (NSAID) are commonly used in sports medicine. NSAID have known anti-inflammatory, analgesic, antipyretic and antithrombotic effects, although their in-vivo effects in treating musculoskeletal injuries in humans remain largely unknown. NSAID analgesic action is not significantly greater than paracetamol for musculoskeletal injury but they have a higher risk profile, with side-effects including asthma exacerbation, gastrointestinal and renal side-effects, hypertension and other cardiovascular diseases. Discussion: The authors recommend an approach to NSAID use in sports medicine whereby simple analgesia is preferentially used when analgesia is the primary desired outcome. However, based both on the current pathophysiological understanding of most injury presentations and the frequency that inflammation may actually be a component of the injury complex, it is premature to suppose that NSAID are not useful to the physician managing sports injuries. The prescribing of NSAID should be cautious and both situation and pathology specific. Both dose and duration minimisation should be prioritised and combined with simple principles of protection, rest, ice, compression, elevation (PRICE), which should allow NSAID-sparing. NSAID use should always be coupled with appropriate physical rehabilitation. Conclusion: NSAID are probably most useful for treating nerve and soft-tissue impingements, inflammatory arthropathies and tenosynovitis. They are not generally indicated for isolated chronic tendinopathy, or for fractures. The use of NSAID in treating muscle injury is controversial. Conditions in which NSAID use requires more careful assessment include ligament injury, joint injury, osteoarthritis, haematoma and postoperatively.

Recreational soccer is an effective health-promoting activity for untrained men

P Krustrup, J J Nielsen, B R Krustrup, J F Christensen, H Pedersen, M B Randers, P Aagaard, A-M Petersen, L Nybo, J Bangsbo. Br J Sports Med 2009;43:825-831.

To examine the effects of regular participation in recreational soccer on health profile, 36 healthy untrained Danish men aged 20–43 years were randomised into a soccer group (SO; n = 13), a running group (RU; n = 12) and a control group (CO; n = 11). Training was performed for 1 h two or three times per week for 12 weeks; at an average heart rate of 82% (SEM 2%) and 82% (1%) of HR_max for SO and RU, respectively. During the 12 week period, maximal oxygen uptake increased (p<0.05) by 13% (3%) and 8% (3%) in SO and RU, respectively. In SO, systolic and diastolic blood pressure were reduced (p<0.05) from 130 (2) to 122 (2) mm Hg and from 77 (2) to 72 (2) mm Hg, respectively, after 12 weeks, with similar decreases observed for RU. After the 12 weeks of training, fat mass was 3.0% (2.7 (0.6) kg) and 1.8% (1.8 (0.4) kg) lower (p<0.05) for SO and RU, respectively. Only SO had an increase in lean body mass (1.7 (0.4) kg, p<0.05), an increase in lower extremity bone mass (41 (8) g, p<0.05), a decrease in LDL-cholesterol (2.7 (0.2) to 2.3 (0.2) mmol/l; p<0.05) and an increase (p<0.05) in fat oxidation during running at 9.5 km/h. The number of capillaries per muscle fibre was 23% (4%) and 16% (7%) higher (p<0.05) in SO and RU, respectively, after 12 weeks. No changes in any of the measured variables were observed for CO. In conclusion, participation in regular recreational soccer training, organised as small-sided drills, has significant beneficial effects on health profile and physical capacity for untrained men, and in some aspects it is superior to frequent moderate-intensity running.

Current concepts: recognition and management of common activity-related gastrointestinal disorders.

Paluska SA.:

The Physician and Sportsmedicine, 37(1):54-63, 2009. Department of Family Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.

Sports medicine clinicians may encounter a wide variety of activity-related gastrointestinal (GI) disorders. The advancing ages and burgeoning obesity rates of the US population have generally increased the prevalence of GI conditions among adults. However, conditioned younger athletes with normal body mass indices also may experience disquieting activity-related GI disorders. While often mild and transient, some of these GI conditions may disrupt exercise routines or pose significant health risks to affected individuals. Gastroesophageal reflux occurs frequently during physical activity and should be empirically treated with activity reduction and dietary modifications in conjunction with antisecretory agents. Persistent or worrisome symptoms merit upper endoscopy, a thorough evaluation for non-GI causes and, rarely, surgery. Altered GI motility commonly occurs during vigorous activities that use dynamic or fluctuating body positions. Dietary and exercise modifications are usually enough to resolve these symptoms. Physical activity may also precipitate GI bleeding from upper and/or lower sources. Although mild or occult bleeding is most common, significant bleeding merits a thorough diagnostic evaluation after stabilization and treatment. Adequate hydration and gradual exercise progression may be particularly helpful to prevent the recurrence of bleeding. The judicious use of medications in conjunction with nonsteroidal anti-inflammatory drug avoidance may also be necessary. Fortunately, most activity-related GI disorders are self-limited and can be managed conservatively. After a brief period of modified activity, clinically stable individuals may progress their activity levels as symptoms allow.