Search

Kevin R Ford,1 Anh-Dung Nguyen,2 Steven L Dischiavi,1 Eric J Hegedus,1 Emma F Zuk,2 Jeffrey B Taylor11Department of Physical Therapy, High Point University, High Point, NC, USA; 2Department of Athletic Training, School of Health Sciences, High Point University, High Point, NC, USAAbstract: Deficits in proximal hip strength or neuromuscular control may lead to dynamic lower extremity valgus. Measures of dynamic lower extremity valgus have been previously shown to relate to increased risk of several knee pathologies, specifically anterior cruciate ligament ruptures and patellofemoral pain. Therefore, hip-focused interventions have gained considerable attention and been successful in addressing these knee pathologies. The purpose of the review was to identify and discuss hip-focused exercise interventions that aim to address dynamic lower extremity valgus. Previous electromyography, kinematics, and kinetics research support the use of targeted hip exercises with non-weight-bearing, controlled weight-bearing, functional exercise, and, to a lesser extent, dynamic exercises in reducing dynamic lower extremity valgus. Further studies should be developed to identify and understand the mechanistic relationship between optimized biomechanics during sports and hip-focused neuromuscular exercise interventions.Keywords: dynamic lower extremity valgus, hip neuromuscular control, ACL injury rehabilitation, patellofemoral pain, hip muscular activation

Kathryn L Beck,1 Jasmine S Thomson,2 Richard J Swift,1 Pamela R von Hurst11School of Food and Nutrition, Massey Institute of Food Science and Technology, College of Health, Massey University Albany, Auckland, 2School of Food and Nutrition, Massey Institute of Food Science and Technology, College of Health, Massey University Manawatu, Palmerston North, New ZealandAbstract: A number of factors contribute to success in sport, and diet is a key component. An athlete's dietary requirements depend on several aspects, including the sport, the athlete's goals, the environment, and practical issues. The importance of individualized dietary advice has been increasingly recognized, including day-to-day dietary advice and specific advice before, during, and after training and/or competition. Athletes use a range of dietary strategies to improve performance, with maximizing glycogen stores a key strategy for many. Carbohydrate intake during exercise maintains high levels of carbohydrate oxidation, prevents hypoglycemia, and has a positive effect on the central nervous system. Recent research has focused on athletes training with low carbohydrate availability to enhance metabolic adaptations, but whether this leads to an improvement in performance is unclear. The benefits of protein intake throughout the day following exercise are now well recognized. Athletes should aim to maintain adequate levels of hydration, and they should minimize fluid losses during exercise to no more than 2% of their body weight. Supplement use is widespread in athletes, with recent interest in the beneficial effects of nitrate, beta-alanine, and vitamin D on performance. However, an unregulated supplement industry and inadvertent contamination of supplements with banned substances increases the risk of a positive doping result. Although the availability of nutrition information for athletes varies, athletes will benefit from the advice of a registered dietician or nutritionist.Keywords

Giovanni Tanda,1 Beat Knechtle2,3 1Polytechnic School, University of Genoa, Genoa, Italy; 2Gesundheitszentrum St Gallen, St Gallen, 3Institute of Primary Care, University of Zurich, Zurich, Switzerland Background: Marathon (42 km) and 100 km ultramarathon races are increasing in popularity. The aim of the present study was to investigate the potential associations of anthropometric and training variables with performance in these long-distance running competitions. Methods: Training and anthropometric data from a large cohort of marathoners and 100 km ultramarathoners provided the basis of this work. Correlations between training and anthropometric indices of subjects and race performance were assessed using bivariate and multiple regression analyses. Results: A combination of volume and intensity in training was found to be suitable for prediction of marathon and 100 km ultramarathon race pace. The relative role played by these two variables was different, in that training volume was more important than training pace for the prediction of 100 km ultramarathon performance, while the opposite was found for marathon performance. Anthropometric characteristics in terms of body fat percentage negatively affected 42 km and 100 km race performance. However, when this factor was relatively low (ie, less than 15% body fat), the performance of 42 km and 100 km races could be predicted solely on the basis of training indices. Conclusion: Mean weekly training distance run and mean training pace were key predictor variables for both marathon and 100 km ultramarathon race performance. Predictive correlations for race performance are provided for runners with a relatively low body fat percentage. Keywords: running, performance, training indices, body fat, sports training

Anna Eriksson,1 Fredrik R Johansson,2 Maria Bäck3–5 1Rehab City Östermalm, Primary Health Care, 2Department of Environmental Medicine, Musculoskeletal and Sports Injury Epidemiology Center, Karolinska Institutet, Stockholm, 3Department of Occupational Therapy and Physiotherapy, Sahlgrenska University Hospital, 4Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, 5Department of Medical and Health Sciences, Division of Physiotherapy, Linköping University, Linköping, Sweden Purpose: This study adds to the previous work in the field of sport-specific fitness testing by evaluating a tennis-specific agility test called “the 20-yard shuttle test”. The aim of the study was to evaluate the test–retest reliability, the inter-rater reliability, and the criterion-related validity of the 20-yard shuttle test on competitive junior tennis players. Participants and methods: Totally, 34 Swedish tennis players (13 girls), mean age 14±1.6 years, participated in the study. To examine test–retest reliability, the subjects performed the 20-yard shuttle test three times on the same day and then the same procedure was repeated after 3 days. To test the inter-rater reliability, the time was measured with a stopwatch simultaneously by two different raters. The time recorded manually was compared to the gold standard of digital timing to evaluate the criterion-related validity. Results: Excellent test–retest reliability was found both within the same day (intraclass correlation coefficient [ICC] 0.95) and between days (ICC 0.91). Furthermore, the results showed excellent inter-rater reliability (ICC 0.99) and criterion-related validity on both test occasions (ICC 0.99). Conclusion: We have provided introductory support for the 20-yard shuttle test as a reliable and valid test for use in competitive junior tennis players. The ease of administration makes this

Elizabeth E Hibberd,1 J Rodney Brown,2 Joseph T Hoffer21Department of Health Science, The University of Alabama, Tuscaloosa, AL, USA; 2Department of Intercollegiate Athletics, The University of Alabama, Tuscaloosa, AL, USAAbstract: The ulnar collateral ligament stabilizes the elbow joint from valgus stress associated with the throwing motion. During baseball pitching, this ligament is subjected to tremendous stress and injury if the force on the ulnar collateral ligament during pitching exceeds the physiological limits of the ligament. Injuries to the throwing elbow in baseball pitchers result in significant time loss and typically surgical intervention. The purpose of this paper is to provide a review of current information to sports medicine clinicians on injury epidemiology, injury mechanics, injury risk factors, injury prevention, surgical interventions, nonsurgical interventions, rehabilitation, and return to play outcomes in baseball pitchers of all levels.Keywords: ulnar collateral ligament, elbow injury, baseball, pitchers

Richard Brown,1 Gaétan Chevalier,2 Michael Hill3 1Department of Human Physiology, University of Oregon, Eugene, OR, 2Developmental and Cell Biology Department, University of California at Irvine, Irvine, CA, 3Garden Way Chiropractic Center and Sports Injury Clinic, Eugene, OR, USAAbstract: Grounding a human to the earth has resulted in changes in the physiology of the body. A pilot study on grounding and eccentric contractions demonstrated shortened duration of pain, reduced creatine kinase (CK), and differences in blood parameters. This follow-up study was conducted to investigate the effects of grounding after moderate eccentric contractions on pain, CK, and complete blood counts. Thirty-two healthy young men were randomly divided into grounded (n=16) and sham-grounded (n=16) groups. On days 1 through 4, visual analog scale for pain evaluations and blood draws were accomplished. On day 1, the participants performed eccentric contractions of 200 half-knee bends. They were then grounded or sham-grounded to the earth for 4 hours on days 1 and 2. Both groups experienced pain on all posttest days. On day 2, the sham-grounded group experienced significant CK increase (P<0.01) while the CK of the grounded group did not increase significantly; the between-group difference was significant (P=0.04). There was also an increase in the neutrophils of the grounded group on day 3 (P=0.05) compared to the sham-grounded group. There was a significant increase in platelets in the grounded group on days 2 through 4. Grounding produced changes in CK and complete blood counts that were not shared by the sham-grounded group. Grounding significantly reduced the loss of CK from the injured muscles indicating reduced muscle damage. These results warrant further study on the effects of earthing on delayed onset muscle damage.Keywords: creatine kinase, free radicals, neutrophils, platelets, reactive oxygen species, ROS

Christian Ehrnthaller,1 Heinz Kusche,2 Florian Gebhard1 1Department of Traumatology, Hand-, Plastic-, and Reconstructive Surgery, Center of Surgery, University of Ulm, Germany; 2Department of Traumatology and Orthopedics, Garmisch-Partenkirchen Medical Center, Germany Introduction: Little is known about the distribution of injuries in competitive snowboarding and there are no reports describing long-term complications of professional snowboarding. To examine the injury distribution and long-term impairments in active and retired professional snowboarders, a retrospective data analysis was performed using a questionnaire. As a control group, injuries of recreational snowboarders of a southern German university clinic were examined. Methods: Retired and active snowboarders were identified from the result lists of the International Ski Federation (FIS) and from the current team lists of the German-speaking European national snowboard teams. After identification, a questionnaire regarding injury distribution/treatment was sent to the athletes and the filled-in questionnaires were subsequently evaluated. Injuries in recreational snowboarding were evaluated by analyzing the medical records and surgical reports for a seven-year period. Results: Compared to the available literature, significantly more severe injuries that necessitated surgical treatment in recreational snowboarders were documented. Most injuries accounted for wrist fractures but also many nonunions and spinal fractures were recorded. Between active professionals, distinct differences in injury distribution were found. The number of days off differed greatly with less days in speed disciplines (35.5 days) and the maximum number of days off in snowboardcross (51 days). Injury distribution varied clearly with more injuries of the upper extremity and ankle in speed disciplines compared to snowboardcross and freestyle professionals, who exhibited more injuries to the lower extremity and head. Freestyle athletes

Beat Knechtle,1,2 Matthias Alexander Zingg,1 Thomas Rosemann,1 Michael Stiefel,1 Christoph Alexander Rüst11Institute of Primary Care, University of Zurich, Zurich, Switzerland; 2Gesundheitszentrum St Gallen, St Gallen, Switzerland Objective: This narrative review summarizes recent intentions to find potential predictor variables for ultra-triathlon race performance (ie, triathlon races longer than the Ironman distance covering 3.8 km swimming, 180 km cycling, and 42.195 km running). Results from studies on ultra-triathletes were compared to results on studies on Ironman triathletes. Methods: A literature search was performed in PubMed using the terms “ultra”, “triathlon”, and “performance” for the aspects of “ultra-triathlon”, and “Ironman”, “triathlon”, and “performance” for the aspects of “Ironman triathlon”. All resulting papers were searched for related citations. Results for ultra-triathlons were compared to results for Ironman-distance triathlons to find potential differences. Results: Athletes competing in Ironman and ultra-triathlon differed in anthropometric and training characteristics, where both Ironmen and ultra-triathletes profited from low body fat, but ultra-triathletes relied more on training volume, whereas speed during training was related to Ironman race time. The most important predictive variables for a fast race time in an ultra-triathlon from Double Iron (ie, 7.6 km swimming, 360 km cycling, and 84.4 km running) and longer were male sex, low body fat, age of 35–40 years, extensive previous experience, a fast time in cycling and running but not in swimming, and origins in Central Europe. Conclusion: Any athlete intending to compete in an ultra-triathlon should be aware that low body fat and high training volumes are highly predictive for overall race time. Little is k

Jonathan J Streit,1 Yousef Shishani,1 Mark Rodgers,2 Reuben Gobezie1 1The Cleveland Shoulder Institute, 2Department of Pathology, University Hospitals of Cleveland, Cleveland, OH, USA Background: Bicipital tendinitis is a common cause of anterior shoulder pain, but there is no evidence that acute inflammation of the extra-articular long head of the biceps (LHB) tendon is the root cause of this condition. We evaluated the histologic findings of the extra-articular portion of the LHB tendon and synovial sheath in order to compare those findings to known histologic changes seen in other tendinopathies. Methods: Twenty-six consecutive patients (mean age 45.4±13.7 years) underwent an open subpectoral biceps tenodesis for anterior shoulder pain localized to the bicipital groove. Excised tendons were sent for histologic analysis. Specimens were graded using a semiquantitative scoring system to evaluate tenocyte morphology, the presence of ground substance, collagen bundle characteristics, and vascular changes. Results: Chronic inflammation was noted in only two of 26 specimens, and no specimen demonstrated acute inflammation. Tenocyte enlargement and proliferation, characterized by increased roundness and size of the cell and nucleus with proteoglycan matrix expansion and myxoid degenerative changes, was found in all 26 specimens. Abundant ground substance, collagen bundle changes, and increased vascularization were visualized in all samples. Conclusion: Anterior shoulder pain attributed to the biceps tendon does not appear to be due to an inflammatory process in most cases. The histologic findings of the extra-articular portion of the LHB tendon and synovial sheath are similar to the pathologic findings in de Quervain tenosynovitis at the wrist, and may be due to a chronic degenerative process similar to this and other tendinopathies of the body. Keywords: biceps tendinitis, biceps tendinopathy, tenosynovium, anterior shoulder pain, long head biceps tendon, his

Jarret M Woodmass,1 John G Esposito,1 Yohei Ono,1,2 Atiba A Nelson,1 Richard S Boorman,1 Gail M Thornton,1,3 Ian KY Lo1 1Department of Surgery, Section of Orthopaedic Surgery, McCaig Institute for Bone and Joint Health, University of Calgary, Calgary, AB, Canada; 2Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan; 3Department of Orthopaedics, University of British Columbia, Vancouver, BC, Canada Purpose: Over the past decade, a number of arthroscopic or arthroscopically assisted reconstruction techniques have emerged for the management of acromioclavicular (AC) separations. These techniques provide the advantage of superior visualization of the base of the coracoid, less soft tissue dissection, and smaller incisions. While these techniques have been reported to provide excellent functional results with minimal complications, discrepancies exist within the literature. This systematic review aims to assess the rate of complications following these procedures. Methods: Two independent reviewers completed a search of Medline, Embase, PubMed, and the Cochrane Library entries up to December 2013. The terms “Acromioclavicular Joint (MeSH)” OR “acromioclavicular* (text)” OR “coracoclavicular* (text)” AND “Arthroscopy (MeSH)” OR “Arthroscop* (text)” were used. Pooled estimates and 95% confidence intervals were calculated assuming a random-effects model. Statistical heterogeneity was quantified using the I2 statistic. Level of evidence: IV Results: A total of 972 abstracts met the search criteria. After removal of duplicates and assessment of inclusion/exclusion criteria, 12 articles were selected for data extraction. The rate of superficial infection was 3.8% and residual shoulder/AC pain or hardware irritation occurred at a rate of 26.7%. The rate of coracoid/clavicle fracture was 5.3% and occurred most commonly with techniques ut

Jean-François Brunelle,1,2 Sébastien Blais-Coutu,1 Kenan Gouadec,3 Éric Bédard,3 Philippe Fait1,2 1Department of Human Kinetics Sciences, 2Research Group on Neuromusculoskeletal Dysfunctions, Université du Québec à Trois-Rivières, QC, Canada; 3Italian Ice Sports Federation, Rome, Italy Introduction: In preparation for a short track speed skating season, eight men and seven women were given yoga sessions during an 8-week high volume training cycle. The sessions were planned according to the postural aspects specific to short track speed skating technical requirements. Three specific goals were selected for the intervention: 1) to observe whether the practice of yoga as postural training could improve the efficiency and the athlete's repertoire along the muscular synergies solicited in the short track speed skating specific technique; 2) to enhance and diversify the motor time-on-task of athletes without changing the prescription of other training stimulus; and 3) to lower the risk of injury during periods with high volumes of training. Methods: A total of 36 sessions of yoga were given. Three postural tests were administered before and after the intervention with 14 angles analyzed. Non-parametric Wilcoxon test was used to compare angles' variations. Results: The 36 yoga sessions totalized 986 minutes of motor time-on-task, registering a proportion of 30% of the global motor time-on-task of the training cycle. Improvements were found in eleven of the 14 angles measured when comparing pre- and post-postural tests (P-value from 0.01 to 0.005). During the 8 weeks, excepting traumatic injuries due to short track speed skating accidents, no skaters suffered injuries linked to the high volume of training. Following the intervention, coaches noticed, following their on-ice feedbacks, an adjustment in the efficiency of the skating technique, in particular regarding hip dis

Tomas Carlsson,1,2 Magnus Carlsson,1,2 Daniel Hammarström,3 Bent R Rønnestad,3 Christer B Malm,2 Michail Tonkonogi1 1School of Education, Health and Social Studies, Dalarna University, Falun, 2Sports Medicine Unit, Umeå University, Umeå, Sweden; 3The Lillehammer Research Center for Medicine and Exercise Physiology, Lillehammer University College, Lillehammer, Norway Abstract: The aim of this study was 1) to validate the 0.5 body-mass exponent for maximal oxygen uptake (V̇O2max) as the optimal predictor of performance in a 15 km classical-technique skiing competition among elite male cross-country skiers and 2) to evaluate the influence of distance covered on the body-mass exponent for V̇O2max among elite male skiers. Twenty-four elite male skiers (age: 21.4±3.3 years [mean ± standard deviation]) completed an incremental treadmill roller-skiing test to determine their V̇O2max. Performance data were collected from a 15 km classical-technique cross-country skiing competition performed on a 5 km course. Power-function modeling (ie, an allometric scaling approach) was used to establish the optimal body-mass exponent for V̇O2max to predict the skiing performance. The optimal power-function models were found to be race speed = 8.83 • (V̇O2max m-0.53)0.66 and lap speed = 5.89 • (V̇O2max m-(0.49+0.018lap))0.43e0.010age, which explained 69% and 81% of the variance in skiing speed, respectively. All the variables contributed to the models. Based on the validation results, it may be recommended that V̇O2max divided by the square root of body mass (mL • min-1 • kg-0.5) should be used when elite male skiers’ performance capability in 15 km classical-technique races is evaluated. Moreover, the body-mass exponent for V̇O2max was demonstrated to be influenced by the distance covered, indicating that heavier skiers have a more pronounced positive pacing profile (ie, rac

Gaurav Sikri, Anirban Bhattacharya Department of Physiology, Armed Forces Medical College, Wanowarie, Pune, IndiaWe read with great interest the review article titled “Wilderness medicine at high altitude: recent developments in the field” by Shah et al.1 The authors have comprehensively summarized the recent advances in the field of high altitude medicine relevant to sports and travel medicine. However, Shah et al have described potential drugs for management of high-altitude illnesses, such as acute mountain sickness (AMS), high altitude cerebral edema, and high altitude pulmonary edema (HAPE) as one group under the section “Novel drug treatment for AMS”. The pathophysiologies of these two sets of diseases (AMS/high altitude cerebral edema as one and HAPE as another set) are different2 and hence it would have been nice to have had the novel drugs described separately to elucidate the therapeutic approach for the two different classes of diseases.View original paper by Shah et al.

Mari Leppänen,1 Kati Pasanen,1 Urho M Kujala,2 Jari Parkkari,1 1Tampere Research Center of Sports Medicine, UKK Institute for Health Promotion Research, Tampere, 2Department of Health Sciences, University of Jyväskylä, Jyväskylä, Finland Background: The popularity of team sports is growing among young people. High training volume and intensity may predispose young athletes to overuse injuries. Research to date has tended to focus on acute injuries rather than overuse injuries. The purpose of this study was to examine the occurrence, nature, and severity of overuse injuries in youth basketball and floorball, with the hypothesis that overuse injuries are frequent in youth team sports. Methods: The study comprised a total of 401 Finnish team sports athletes (207 basketball and 194 floorball players). The data were collected using a detailed questionnaire. The participants (mean age 15.8±1.9 years) responded to the questionnaire covering information on overuse injuries during the previous 12 months. Results: A total of 190 overuse injuries was reported (97 in basketball and 93 in floorball). In both sports, most of the injuries involved the lower extremities (66% and 55% of all injuries in basketball and floorball, respectively). In basketball, the most commonly injured site was the knee (44 cases, 45%). In floorball, the most commonly injured sites were the lower back/pelvis (36 cases, 39%) and knee (32 cases, 34%). Overuse injuries caused an average time loss from full participation of 26±50 (median 7) days in basketball and 16±37 (median 5) days in floorball. Conclusion: Overuse injuries are a common problem in youth team sports, and often cause long-term absence from full participation. The findings suggest that injury reduction and training load monitoring strategies are needed in the field. More research using explicit prospective data collection is needed to better understand the proble

Marco Antonio Schueda,1 Diego Costa Astur,2 Rodrigo Schueda Bier,3 Debora Schueda Bier,4 Nelson Astur,5 Moisés Cohen2 1Serviço de Pós Graduação em Cirurgia do Joelho e Artroscopia do IOT e Traumasports de Joinville, Joinville, Santa Catarina, 2Departamento de Ortopedia e Traumatologia da Escola Paulista de Medicina, São Paulo, 3Serviço de Cirurgia do Joelho e Artroscopia do IOT e Traumasports de Joinville, Joinville, Santa Catarina, 4Pontifícea Universidade Católica, Curitiba, 5Faculdade de Ciencias Médicas da Santa Casa de Misericórdia de São Paulo, São Paulo, Brazil Abstract: The purpose of this research was to identify reliable tomographic measurements that can detect patellofemoral abnormality and allow quantification of the risk of patellar dislocation in patients with potential patellar instability. A cross-sectional study in 921 patients with anterior pain or knee instability of at least 6 months' duration was conducted from July 2001 to December 2009. All subjects were clinically evaluated and underwent radiography and computed tomography of their knees. According to their degree of dislocating patellar dysplasia, the subjects were classified into groups for statistical comparison. There was a statistically significant difference in all measurements when the groups were compared, except for external tibial torsion angle. The most sensitive and specific measurements for determining patellar instability were the trochlear groove angle, tibial tubercle-trochlear groove distance, average patellar tilt, and average patellar height. Patients with potential patellar instability, increased tibial tubercle-trochlear groove distance, and patellar height, tilt, and deviation measurements had a greater risk for patellar dislocation. The clinical relevance of this study is to determine measurements that are able to tell us

Yasutaka Tashiro, Ken Okazaki, Yukihide Iwamoto Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan Purpose: We aimed to clarify the distance between the anteromedial (AM) bundle and posterolateral (PL) bundle tunnel-aperture centers by simulating the anatomical femoral tunnel placement during double-bundle anterior cruciate ligament reconstruction using 3-D computer-aided design models of the knee, in order to discuss the risk of tunnel overlap. Relationships between the AM to PL center distance, body height, and sex difference were also analyzed. Patients and methods: The positions of the AM and PL tunnel centers were defined based on previous studies using the quadrant method, and were superimposed anatomically onto the 3-D computer-aided design knee models from 68 intact femurs. The distance between the tunnel centers was measured using the 3-D DICOM software package. The correlation between the AM–PL distance and the subject's body height was assessed, and a cutoff height value for a higher risk of overlap of the AM and PL tunnel apertures was identified. Results: The distance between the AM and PL centers was 10.2±0.6 mm in males and 9.4±0.5 mm in females (P<0.01). The AM–PL center distance demonstrated good correlation with body height in both males (r=0.66, P<0.01) and females (r=0.63, P<0.01). When 9 mm was defined as the critical distance between the tunnel centers to preserve a 2 mm bony bridge between the two tunnels, the cutoff value was calculated to be a height of 160 cm in males and 155 cm in females. Conclusion: When AM and PL tunnels were placed anatomically in simulated double-bundle anterior cruciate ligament reconstruction, the distance between the two tunnel centers showed a strong positive correlation with body height. In cases with relatively short stature, the AM and PL tunnel apertures are considered to be at a higher

Shane D Scholten,1 Igor N Sergeev,2 Qingming Song,3 Chad B Birger41Exercise and Sport Sciences, Augustana College, Sioux Falls, 2Department of Health and Nutritional Sciences, South Dakota State University, Brookings, SD, 3Gold Green Farm Corporation, Hammonton, NJ, 4Center for Health Outcomes and Prevention Research, Sanford Research, Sioux Falls, SD, USAIntroduction: Vitamin D and the antioxidant quercetin, are promising agents for improving physical performance because of their possible beneficial effects on muscular strength and cardiorespiratory fitness.Purpose: The purpose of this study was to determine the effects of increased intakes of vitamin D, quercetin, and their combination on antioxidant status, the steroid hormone regulators of muscle function, and measures of physical performance in apparently healthy male adults engaged in moderate-to-vigorous-intensity exercise training.Methods: A total of 40 adult male participants were randomized to either 4,000 IU vitamin D/d, 1,000 mg/d quercetin, vitamin D plus quercetin, or placebo for 8 weeks. Measures of cardiorespiratory fitness and muscle function, blood markers for antioxidant and vitamin D status, and hormones 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) and testosterone were measured pre- and postsupplementation.Results: At enrollment, 88.6% of participants were vitamin D sufficient (serum 25-hydroxyvitamin D >50 nmol/L) and had normal serum testosterone levels. Supplementation with vitamin D significantly increased serum 25(OH)D concentration (by 87.3% in the vitamin D group, P<0.001) and was associated with an increasing trend of testosterone concentration. There were no changes in concentration of 1,25(OH)2D3 and markers of antioxidant status associated with vitamin D or quercetin supplementation. No improvements in physical performance measures associated with vitamin D and quercetin supplementation were found.Conclusion: The findings obtained demonstrate that long-term vitamin D and querc

Amilton Vieira,1 Martim Bottaro,1 Joao B Ferreira-Junior,1,4 Carlos Vieira,1 Vitor A Cleto,1 Eduardo L Cadore,2 Herbert G Simões,3 Jake Do Carmo,1 Lee E Brown5 1College of Physical Education, University of Brasília, Brasília, 2College of Physical Education, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, 3College of Physical Education, Catholic University of Brasília, Brasília, 4Federal Institute of Triângulo Mineiro, Paracatu, Brazil; 5Department of Kinesiology, California State University, Fullerton, CA, USA Abstract: Whole-body cryotherapy (WBC) has been used as a recovery strategy following different sports activities. Thus, the aim of the study reported here was to examine the effect of WBC on vertical jump recovery following a high-intensity exercise (HIE) bout. Twelve trained men (mean ± standard deviation age = 23.9±5.9 years) were randomly exposed to two different conditions separated by 7 days: 1) WBC (3 minutes of WBC at −110°C immediately after the HIE) and 2) control (CON; no WBC after the HIE). The HIE consisted of six sets of ten repetitions of knee extensions at 60° · s−1 concentric and 180° · s−1 eccentric on an isokinetic dynamometer. The vertical jump test was used to evaluate the influence of HIE on lower extremity muscular performance. The vertical jump was performed on a force platform before HIE (T1) and 30 minutes after (T2) the WBC and CON conditions. As a result of HIE, jump height, muscle power, and maximal velocity (Vmax) had significant decreases between T1 and T2, however no significance was found between the WBC and CON conditions. The results indicate that one session of WBC had no effect on vertical jump following an HIE compared with a CON condition. WBC may not improve muscle-function (dependent on stretch-shortening cycle) recovery in very short periods (i

Matthias A Zingg,1 Beat Knechtle,1,2 Thomas Rosemann,1 Christoph A Rüst1 1Institute of Primary Care, University of Zurich, Zurich, Switzerland; 2Gesundheitszentrum St Gallen, St Gallen, Switzerland Abstract: Anecdotal reports have assumed that women would be able to outrun men in long-distance running. The aim of this study was to test this assumption by investigating the changes in performance difference between sexes in the best ultramarathoners in 50-mile, 100-mile, 200-mile, 1,000-mile, and 3,100-mile events held worldwide between 1971 and 2012. The sex differences in running speed for the fastest runners ever were analyzed using one-way analysis of variance with subsequent Tukey–Kramer posthoc analysis. Changes in sex difference in running speed of the annual fastest were analyzed using linear and nonlinear regression analyses, correlation analyses, and mixed-effects regression analyses. The fastest men ever were faster than the fastest women ever in 50-mile (17.5%), 100-mile (17.4%), 200-mile (9.7%), 1,000-mile (20.2%), and 3,100-mile (18.6%) events. For the ten fastest finishers ever, men were faster than women in 50-mile (17.1%±1.9%), 100-mile (19.2%±1.5%), and 1,000-mile (16.7%±1.6%) events. No correlation existed between sex difference and running speed for the fastest ever (r2=0.0039, P=0.91) and the ten fastest ever (r2=0.15, P=0.74) for all distances. For the annual fastest, the sex difference in running speed decreased linearly in 50-mile events from 14.6% to 8.9%, remained unchanged in 100-mile (18.0%±8.4%) and 1,000-mile (13.7%±9.1%) events, and increased in 3,100-mile events from 12.5% to 16.9%. For the annual ten fastest runners, the performance difference between sexes decreased linearly in 50-mile events from 31.6%±3.6% to 8.9%±1.8% and in 100-mile events from 26.0%±4.4% to 24.7%±0.9%. To summarize, the fastest men were ~17%&n

Aleksandr K Drozdovski Sports Training Center for Russian Teams, Moscow, Russia Abstract: Based on experimental studies in education, professions and sports, an attempt was made to combine the following two historically disconnected research directions in the study of the natural human traits into a single coordinate system: Pavlov’s theory on the properties of the nervous system, as well as the types of higher nervous activity, and Jung’s theory on psychological types. It is noted that Pavlov’s school of thought was developed by his followers in Russia within the scientific school of differential psychophysiology, while Yung’s theory was developed through the works of well-known American researchers Myers and Keirsey. The spatial model that is presented here rests on the knowledge of the properties of the human nervous system and enables the prediction of psychological characteristics, temperament, and psychological types of individuals belonging to a wide age range. Keywords: differential psychophysiology, properties of the nervous system, typological complex of properties, psychological properties, temperament and psychological type

Matthew D Barrett,1 Terence F McLoughlin,2 Kieran R Gallagher,1 Don Gatherer,3 Michael TR Parratt,1 Jonathan R Perera,1 Tim WR Briggs1 1Royal National Orthopaedic Hospital, Stanmore, Middlesex, United Kingdom; 2Royal Liverpool University Hospital, Liverpool, Mersey Deanery, United Kingdom; 3The Gatherer Partnership, Aylesbury, United Kingdom Purpose: To investigate the effect of a tailored neck muscle conditioning program on neck muscle strength, neck muscle fatigue, and range of neck movement in 16–18-year-old male rugby players. Materials and methods: Thirty-four male rugby players were divided into forward and back playing positions and randomized within these groups. Seventeen players were randomly assigned to each group. The test group was given a tailored 6-week exercise regime based on their baseline measurements to be performed three times a week in addition to their normal training and playing. The control group trained and played as normal. The outcome measures used were cervical spine range of movement, neck strength, and neck muscle fatigability. Results: There were no clinically relevant statistically significant differences between the two groups. Trends identified between the two groups suggest that a tailored neck exercise program increases neck strength, particularly neck extension, and increases resistance to fatigue, as well as influencing right- and left-sided neck muscle balance. A reduction in range of movement was also demonstrated in the test group. There was a great deal of variability in range of movement and strength within this age group. No previously undiagnosed neck conditions were detected, and there were no adverse events reported. Conclusion: This study has shown that neck strength, range of movement, and susceptibility of the neck muscles to fatigue can be influenced using a focused neck training regime. It forms an important basis for a larger, multicenter study to ensure the neck is given due attention in rugby training

Natalia Covarrubias,1 Subir Bhatia,2 Luis F Campos,3 Dahn V Nguyen,2,3 Eric Y Chang1,4,51Department of Physical Medicine and Rehabilitation, University of California Irvine, Irvine, CA, USA; 2School of Medicine, University of California Irvine, Irvine, CA, USA; 3Institute for Clinical and Translational Science, Irvine, CA, USA; 4Department of Anesthesiology and Perioperative Care, University of California Irvine, Irvine, CA, USA; 5Reeve-Irvine Research Center, Irvine, CA, USA Objective: To correlate training habits of Taekwondo (TKD) athletes to risk for injury. Background: TKD is a Korean marital art that has been growing in popularity, with nearly 2 million individuals practicing the sport in the United States. Because of the combative nature of the sport, injuries are an inherent risk. However, data on proper training habits, types of injuries sustained during training, and recommendations for athletes to avoid injury are lacking. Frequently, studies of TKD evaluate athletes’ injuries during tournaments, but most do not evaluate athletes in training. Hypothesis: Increased training would potentially create more injuries secondary to increased exposure. Methods: This is a cross-sectional observational survey of 72 collegiate TKD athletes from the Pacific West Sanctioned Taekwondo Tournaments in the 2008–2009 season. Variables analyzed during training and competitions were training sessions per week, workout habits, belt level, years of experience, and characteristics of injury (location, type, mechanism, situation, treatment, and days missed). Results: TKD training habits of individuals who practiced four or more times per week (odds ratio [OR], 4.5; P=0.005) or sparred for more than 2 hours (OR, 8.7; P=0.003) were associated with significantly increased odds (risk) of sustaining an injury. Those who had more than 3 years of tournament experience were more likely to sustain an injury (OR, 0.198; P=0.020). Conclusion: Increased risk for injury wi

Beat Knechtle,1,2 Thomas Rosemann,1 Matthias A Zingg,1 Michael Stiefel,1 Christoph A Rüst11Institute of Primary Care, University of Zurich, Zurich, 2Gesundheitszentrum St Gallen, St Gallen, SwitzerlandAbstract: Pacing strategy has been investigated in elite 100 km and elite 161 km (100 mile) ultra-marathoners, but not in age group ultra-marathoners. This study investigated changes in running speed over segments in male elite and age group 100 km ultra-marathoners with the assumption that running speed would decrease over segments with increasing age of the athlete. Running speed during segments in male elite and age group finishers for 5-year age groups (ie, 18–24 to 65–69 years) in the 100 km Lauf Biel in Switzerland was investigated during the 2000–2009 period. Average running speed over segment time station (TS) TS1–TS2 (56.1 km) was compared with running speed Start–TS1 (38 km) and Start–TS3 (76.7 km) and running speed TS2–TS3 was compared with running speed Start–Finish. For the top ten athletes in each edition, running speed decreased from 2000 to 2009 for TS1–TS2 and TS2–TS3 (P<0.0001) but not in TS3–Finish (P>0.05). During TS1–TS2, athletes were running at 98.0%±2.1% of the running speed of Start–TS1. In TS2–TS3, they were running at 94.6%±3.4% of the running speed of TS1–TS2. In TS3–Finish, they were running at 95.5%±3.8% of running speed in TS2–TS3. For age group athletes, running speed decreased in TS1–TS2 and TS2–TS3. In TS3–Finish, running speed remained unchanged with the exception of the age group 40–44 years for which running speed increased. Running speed showed the largest decrease in the age group 18–24 years. To summarize, the top ten athletes in each edition maintained their

Adae O Amoako,1 Agyenim B Amoako,2 George GA Pujalte3 1Department of Family and Community Medicine, Penn State Hershey Medical Center, Hershey, PA, USA; 2Department of Family Medicine, University of Arkansas for Medical Sciences Northwest, Fayetteville, AR, USA; 3Sports Medicine, Divisions of Primary Care, and Orthopedics, Mayo Clinic Health System, Waycross, GA, USA Background and objective: Family physicians are expected to be comfortable in treating common sports injuries. Evidence shows a limited level of comfort in treating these injuries in pediatric and internal medicine residents. Studies are lacking, however, in family medicine residents. The purpose of this study is to assess the comfort level of family medicine residents in treating common sports injuries in adults and children based on their perceived level of knowledge and attitudes. Methods: This is a cross-sectional study of family medicine residents in the United Sates. A written survey of 25 questions related to sports injury knowledge and factors affecting comfort level were collected. A chi-square test was implemented in calculating P-values. Results: Five hundred and fifty-seven residents responded to the survey. A higher percentage of doctors of osteopathy (86.6%, 82.5%, 69.6%, and 68.7%) compared to doctors of medicine (78.5%, 71.6%, 53.4%, and 52.8%) respectively identified ankle sprain, concussion, plantar fasciitis, and lateral epicondylitis as common injuries, and felt comfortable in treating them (P-values =0.015, 0.004, 0.0001, and 0.0002, respectively). Residents with high interest in sports medicine correctly identified the injuries as common and felt comfortable treating them as well (knowledge, P=0.027, 0.0029, <0.0001, and 0.0001, respectively; comfort level, P=0.0016, <0.0001, 0.0897, and 0.0010, respectively). Conclusion: Medical education background, factors that affect training, and an interest in sports medicine contribute to residents' knowledge and comfor

Leamor Kahanov,1 Lindsey E Eberman,2 Kenneth E Games,2 Mitch Wasik2 1College of Health Science, Misericordia University, Dallas, PA, USA; 2Department of Applied Medicine and Rehabilitation, Indiana State University, Terre Haute, IN, USA Abstract: Stress fractures account for between 1% and 20% of athletic injuries, with 80% of stress fractures in the lower extremity. Stress fractures of the lower extremity are common injuries among individuals who participate in endurance, high load-bearing activities such as running, military and aerobic exercise and therefore require practitioner expertise in diagnosis and management. Accurate diagnosis for stress fractures is dependent on the anatomical area. Anatomical regions such as the pelvis, sacrum, and metatarsals offer challenges due to difficulty differentiating pathologies with common symptoms. Special tests and treatment regimes, however, are similar among most stress fractures with resolution between 4 weeks to a year. The most difficult aspect of stress fracture treatment entails mitigating internal and external risk factors. Practitioners should address ongoing risk factors to minimize recurrence. Keywords: medial tibial stress syndrome, stress injury, nonunion stress fracture

Saki Hamano,1 Eisuke Ochi,2 Yosuke Tsuchiya,3 Erina Muramatsu,4 Kazuhiro Suzukawa,5 Shoji Igawa1 1Department of Sports Nutrition, Nippon Sport Science University, Yokohama, Kanagawa, 2Graduate School of Education, Okayama University, Okayama, 3Laboratory of Health and Sports Sciences, Meiji Gakuin University, Yokohama, Kanagawa, 4Department of Natural Sciences, Nippon Sport Science University, Setagaya, Tokyo, .5Laboratory of Preventive Medicine and Public Health, Nippon Sport Science University, Setagaya, Tokyo, Japan Objective: Canoe sprint is divided into canoe and kayak. The difference between the two competitions is in physical performance. The aim of the present study was to compare and investigate the relationship between physical characteristics and fitness between the two canoe sprint competitors. Methods: Subjects were 11 canoe paddlers (C) and 12 kayak paddlers (K). They underwent anthropometric characteristics, body composition and fitness tests, and 120 s all-out tests using a canoe and kayak ergometer. The unpaired t-test was used to test for significant differences between disciplines, while Pearson's correlation coefficient was used to examine the association between each measurement item and the performance test. Results: The age, height, body mass, body mass index, and total body fat were, C: 20.6±0.9 yr, 172.8±5.2 cm, 70.8±7.8 kg, 23.7±1.9, 14.4%±3.5%; and K: 19.7±1.2 yr, 172.8±5.3 cm, 69.5±7.8 kg, 23.2±2.1, 12.1%±3.6%, respectively. No significant differences were seen in any of the items for physical characteristics or fitness between C and K. A correlation analysis of performance tests and each measurement item revealed a positive correlation with low-speed isokinetic knee extension and flexion strength for C only (extension: r=0.761; flexion: r=0.784; P<0.01). In addition, performance tests were positively correlated wit

Ibrahim Karaman,1 Ahmet Guney,1 Fatih Dogar,2 Mithat Oner,1 Okkes Bilal3 1Department of Orthopaedics and Traumatology, Erciyes University Medical Faculty, 2Department of Orthopaedics and Traumatology, Training and Research Hospital, Kayseri, 3Department of Orthopaedics and Traumatology, Kahramanmaras Sütçü Imam University Medical Faculty, Kahramanmaras, Turkey Abstract: Synovial chondromatosis is a rare and benign proliferative disorder of the synovial membrane in joints and bursae. Herein, we present the case of a 34-year-old male with synovial chondromatosis that caused limitation in the elbow joint in terms of mechanical function. Keywords: chondromatosis, elbow, loose bodies, mechanical block

Jarret M Woodmass,1 Graeme Matthewson,1 Yohei Ono,1,2 Aaron J Bois,1 Richard S Boorman,1 Ian KY Lo,1 Gail M Thornton1,31Department of Surgery, Section of Orthopaedic Surgery, McCaig Institute for Bone and Joint Health, University of Calgary, Calgary, AB, Canada; 2Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan; 3Department of Orthopaedics, University of British Columbia, Vancouver, BC, Canada Purpose: The purpose of this study was to evaluate the mechanical performance of different suture locking mechanisms including: i) interference fit between the anchor and the bone (eg, 4.5 mm PushLock, 5.5 mm SwiveLock), ii) internal locking mechanism within the anchor itself (eg, 5.5 mm SpeedScrew), or iii) a combination of interference fit and internal locking (eg, 4.5 mm MultiFIX P, 5.5 mm MultiFIX S). Methods: Anchors were tested in foam blocks representing normal (20/8 foam) or osteopenic (8/8 foam) bone, using standard suture loops pulled in-line with the anchor to isolate suture locking. Mechanical testing included cyclic testing for 500 cycles from 10 N to 60 N at 60 mm/min, followed by failure testing at 60 mm/min. Displacement after 500 cycles at 60 N, number of cycles at 3 mm displacement, load at 3 mm displacement, and maximum load were evaluated. Results: Comparing 8/8 foam to 20/8 foam, load at 3 mm displacement and maximum load were significantly decreased (P<0.05) with decreased bone quality for anchors that, even in part, relied on an interference fit suture locking mechanism (ie, 4.5 mm PushLock, 5.5 mm SwiveLock, 4.5 mm MultiFIX P, 5.5 mm MultiFIX S). Bone quality did not affect the mechanical performance of 5.5 mm SpeedScrew anchors which have an isolated internal locking mechanism. Conclusion: The mechanical performance of anchors that relied, even in part, on interference fit were affected by bone quality. Isolated internal locking knotless suture anchors functioned independently of bone quality. Ancho