Nick Webborn

The early management of muscle strains in the elite athlete: best practice in a world with a limited evidence basis.

From 12 to 14 December 2007 UK Sport held a think tank on “muscle strains” in London. This brought together many of UK Sport’s top sports medicine clinicians along with three invited international experts. Many issues of muscle strains were discussed over the three days, but the aspect that attracted the most attention was the early management of strains in the elite athlete. A consensus summary of conclusions on this specific topic from the think tank is presented here. The international experts were chosen by request of the UK clinicians for different reasons. Drs Best (basic science) and Orchard (epidemiology) are recognised internationally by the peer-review system as experts in their fields. Dr Mueller-Wohlfahrt is also recognised internationally as Europe’s premier clinician in the early management of muscle strains. This recognition was initially bestowed on him by his patients, most notably from the thousands of professional football players he has managed over the past 30 years from every country in Europe. Increasingly this recognition has been accorded by the “mainstream” clinicians in the United Kingdom, hence his invitation to the think tank. With the reserve typical of both the British and the scientific community, a common assessment of Dr Mueller-Wohlfahrt’s methods by delegates was “initially I had to be sceptical, but I have seen and heard of so many good results that I am now curious to know why these good outcomes are occurring”. One session of the think tank involved an assessment of our “expert recommendations” for the early management of muscle strains in the elite athlete and a judgement of the evidence base for making the recommendations. The evidence base part was generally easy: almost all of our so-called knowledge has a basis …

Aerobic capacity and peak power output of elite quadriplegic games players

Background: Participation in wheelchair sports such as tennis and rugby enables people with quadriplegia to compete both individually and as a team at the highest level. Both sports are dominated by frequent, intermittent, short term power demands superimposed on a background of aerobic activity. Objective: To gain physiological profiles of highly trained British quadriplegic athletes, and to examine the relation between aerobic and sprint capacity. Methods: Eight male quadriplegic athletes performed an arm crank exercise using an ergometer fitted with a Schoberer Rad Messtechnik (SRM) powermeter. The sprint test consisted of three maximum-effort sprints of five seconds duration against a resistance of 2%, 3%, and 4% of body mass. The highest power output obtained was recorded (PPO). Peak oxygen consumption (V̇o2peak), peak heart rate (HRpeak), and maximal power output (POaer) were determined. Results: Mean POaer was 67.7 (16.2) W, mean V̇o2peak was 0.96 (0.17) litres/min, and HRpeak was 134 (19) beats/min for the group. There was high variability among subjects. Peak power over the five second sprint for the group was 220 (62) W. There was a significant correlation between V̇o2peak (litres/min) and POaer (W) (r  =  0.74, p<0.05). Conclusions: These British quadriplegic athletes have relatively high aerobic fitness when compared with the available literature. Moreover, the anaerobic capacity of these athletes appeared to be relatively high compared with paraplegic participants.

The epidemiology of injuries at the London 2012 Paralympic Games

Background The characteristics and incidence of injuries at the Summer Paralympic Games have not previously been reported. A better understanding of injuries improves the medical care of athletes and informs future injury prevention strategies. Objective The objective of this prospective cohort study was to characterise the incidence and nature of injuries during the London 2012 Summer Paralympic Games. Methods Injury information was obtained from two databases. One database was populated from medical encounter forms completed by providers at the time of assessment in one of the medical stations operated by the Organising Committee. The second database was populated daily with information provided by team medical personnel who completed a comprehensive, web-based injury survey. Results The overall injury incidence rate was 12.7 injuries/1000 athlete-days. Injury rates were similar in male and female athletes. The precompetition injury rates in women were higher than those in the competition period. Higher injury rates were found in older athletes and certain sports such as football 5-a-side (22.4 injuries/1000 athlete-days). Overall, 51.5% of injuries were new onset acute traumatic injuries. The most commonly injured region (percentage of all injuries) was the shoulder (17.7%), followed by the wrist/hand (11.4%), elbow (8.8%) and knee (7.9%). Conclusions This is the largest and most comprehensive epidemiological report examining injuries in Paralympic athletes. Injury rates differ according to age and sport. Upper limb injuries are common. The knowledge gained from this study will inform future injury surveillance studies and the development of prevention strategies in Paralympic sport. The Epidemiology of Injuries at the London 2012 Paralympic Games.

Illness and injury in athletes during the competition period at the London 2012 Paralympic Games: development and implementation of a web-based surveillance system (WEB-IISS) for team medical staff

Background In this study we describe (1) the implementation of a novel web-based injury and illness surveillance system (WEB-IISS) for use by a team of physicians at multisport events and (2) the incidence and characteristics of injuries and illness in athletes during the London 2012 Paralympic Games. Methods Overall, 3565 athletes from 160 of the 164 participating countries were followed daily over a 14-day period, consisting of a precompetition period (3 days), and a competition period (11 days) (49 910 athlete-days). Daily injury and illness data were obtained from teams with their own medical support (78 teams, 3329 athletes) via the WEB-IISS, and without their own medical support through the London Organising Committee of the Olympic Games and Paralympic Games database (82 teams and 236 athletes). Results There were no differences between incidence rates (IR) of injury and illness, or between the precompetition and competition periods. The IR of injury during the competition period was 12.1/1000 athlete-days, with an incidence proportion (IP) of 11.6% (95% CI 11.0% to 13.3%). Upper limb injuries (35%), particularly of the shoulder (17%) were most common. The IR of illness during the competition period was 12.8/1000 athlete-days (95% CI 12.18 to 1421), with an IP of 10.2%. The IP was highest in the respiratory system (27.4%), skin (18.3%) and the gastrointestinal (14.5%) systems. Conclusions During the competition period, the IR and IP of illness and injury at the Games were similar and comparable to the observed rates in other elite competitions. In Paralympic athletes, the IP of upper limb injuries is higher than that of lower limb injuries and non-respiratory illnesses are more common.

The injury experience at the 2010 winter paralympic games.

ObjectiveThe objective of this study was to examine incidence proportion and the characteristics of athlete injuries sustained during the 2010 Vancouver Paralympic Games. DesignDescriptive epidemiological study. SettingAll medical venues at the 2010 Vancouver Paralympic Games, Canada. ParticipantsA total of 505 athletes from 44 National Paralympic Committees participating in the 2010 Vancouver Winter Paralympic Games. Assessment of Risk FactorsBaseline covariates included sport specificity (ie, ice sledge hockey, alpine skiing, Nordic skiing, wheelchair curling), gender, age, and disability classification. Main Outcome MeasuresAll injuries that occurred during the 2010 Vancouver Paralympic Games. “Injury” was defined as any sport-related musculoskeletal complaint that caused the athlete to seek medical attention during the study period, regardless of the athletes ability to continue with training or competition. ResultsThe Injury Surveillance System identified a total of 120 injuries among 505 athletes [incidence proportion = 23.8% (95% confidence interval, 20.11-27.7)] participating in the 2010 Winter Paralympic Games. There was a similar injury incidence proportion among male (22.8%) and female (26.6%) athletes [incidence rate ratio = 1.1 (95% confidence interval, 0.7-1.7)]. Medical encounters for musculoskeletal complaints were generated in 34% of all sledge hockey athletes, 22% of alpine ski racers, 19% of Nordic skiers, and 18% of wheelchair curling athletes. ConclusionsThe Injury Surveillance System identified sport injuries in 24% of all athletes participating in the 2010 Winter Paralympic Games. The injury risk was significantly higher than during the 2002 (9.4%) and 2006 (8.4%) Winter Paralympic Games. This may reflect improved data collection systems but also highlights the high risk of acute injury in alpine skiing and ice sledge hockey at Paralympic Games. These data will assist future Organizing Committees with the delivery of medical care to athletes with a disability and guide future injury prevention research.

Effects of hypoxia on muscle protein synthesis and anabolic signaling at rest and in response to acute resistance exercise.

Chronic reductions in tissue O(2) tension (hypoxia) are associated with muscle atrophy and blunted hypertrophic responses to resistance exercise (RE) training. However, the effect of hypoxia on muscle protein synthesis (MPS) at rest and after RE is unknown. In a crossover study, seven healthy men (21.4 ± 0.7 yr) performed unilateral leg RE (6 × 8 repetitions at 70% 1-repetition maximum) under normoxic (20.9% inspired O(2)) and normobaric hypoxic (12% inspired O(2) for 3.5 h) postabsorptive conditions. Immediately after RE the rested leg was biopsied, and a primed continuous infusion of [1,2-(13)C(2)]leucine was maintained for 2.5 h before final biopsies from both legs to measure tracer incorporation and signaling responses (i.e., ribosomal S6 kinase 1). After 3.5 h of hypoxia, MPS was not different from normoxia in the rested leg (normoxia 0.033 ± 0.016 vs. hypoxia 0.043 ± 0.016%/h). MPS increased significantly from baseline 2.5 h after RE in normoxia (0.033 ± 0.016 vs. 0.104 ± 0.038%/h) but not hypoxia (0.043 ± 0.016 vs. 0.060 ± 0.063%/h). A significant linear relationship existed between MPS 2.5 h after RE in hypoxia and mean arterial blood O(2) saturation during hypoxia (r(2) = 0.49, P = 0.04). Phosphorylation of p70S6K(Thr389) remained unchanged in hypoxia at rest but increased after RE in both normoxia and hypoxia (2.6 ± 1.2-fold and 3.4 ± 1.1-fold, respectively). Concentrations of the hypoxia-responsive mTOR inhibitor regulated in development and DNA damage-1 were unaltered by hypoxia or RE. We conclude that normobaric hypoxia does not reduce MPS over 3.5 h at rest but blunts the increased MPS response to acute RE to a degree dependent on extant SpO(2).

Factors associated with illness in athletes participating in the London 2012 Paralympic Games: a prospective cohort study involving 49 910 athlete-days.

Background The incidence and factors associated with illness in Paralympic athletes have not been documented. Aim To determine the factors associated with illness in athletes participating in the London 2012 Paralympic Games. Methods A cohort of 3565 athletes from 160 of the 164 participating countries in the London 2012 Paralympic Games were followed over a 14-day period (precompetition period=3 days, competition period=11 days; 49 910 athlete-days). Daily illness data were obtained from (1) teams with their own medical support who completed a daily illness log (78 teams, 3329 athletes) on a novel web-based system and (2) teams without their own medical support through the local organising committee database (82 teams, 236 athletes). Illness information from all athletes included age, gender, type of sport and the main system affected. Main outcome measurement Incidence rate (IR) of illness (illness per 1000 athlete-days) and factors associated with IR (time period, gender, age and sport). Results The IR of illness was 13.2 (95% CI 12.2 to 14.2). The highest IR of illness was in the respiratory system, followed by the skin, digestive, nervous and genitourinary systems. The IR in the precompetition period was similar to that in the competition period, but the IR was significantly higher in athletics compared with other sports. Age and gender were not independent predictors of illness. Conclusions Illness is common in Paralympic athletes and the main factor associated with higher IR of illness was the type of sport (athletics).

Descriptive Epidemiology of Paralympic Sports Injuries

Paralympic sports have seen an exponential increase in participation since 16 patients took part in the first Stoke Mandeville Games on the opening day of the 1948 London Olympic Games. More than 4,000 athletes took part in the London 2012 Paralympic Games. Few sporting events have seen such rapid evolution. This rapid pace of change also has meant challenges for understanding the injury risks of participation, not only because of the variety of sports, impairment types, the evolution of adapted equipment but also because of the inclusion of additional impairment types and development of new sports over time. Early studies were limited in scope but patterns of injuries are slowly emerging within Winter and Summer Paralympic sports. The IPCs London 2012 study is the largest to date with a prospective cohort study involving 49,910 athlete‐days. The results identified large differences across sports and highlighted the need for longitudinal sport specific studies rather than solely games‐time studies. This will require collaboration with international sports federations to examine injury patterns and risk factors for injury in this population to appropriately inform injury prevention strategies. Further studies will also need to address the impact of sporting participation, injury, and future health.

Exercise-induced metabolic fluctuations influence AMPK, p38-MAPK and CaMKII phosphorylation in human skeletal muscle

During transition from rest to exercise, metabolic reaction rates increase substantially to sustain intracellular ATP use. These metabolic demands activate several kinases that initiate signal transduction pathways which modulate transcriptional regulation of mitochondrial biogenesis. The purpose of this study was to determine whether metabolic fluctuations per se affect the signaling cascades known to regulate peroxisome proliferator‐activated receptor γ coactivator‐1α (PGC‐1α). On two separate occasions, nine men performed a continuous (30‐min) and an intermittent exercise (30 × 1‐min intervals separated by 1‐min of recovery) at 70% of V˙O2peak . Skeletal muscle biopsies from the vastus lateralis were taken at rest and at +0 h and +3 h after each exercise. Metabolic fluctuations that correspond to exercise‐induced variation in metabolic rates were determined by analysis of VO2 responses. During intermittent exercise metabolic fluctuations were 2.8‐fold higher despite identical total work done to continuous exercise (317 ± 41 vs. 312 ± 56 kJ after intermittent and continuous exercise, respectively). Increased phosphorylation of AMP‐activated protein kinase (AMPK) (~2.9‐fold, P < 0.01), calcium/calmodulin‐dependent protein kinase II (CaMKII) (~2.7‐fold, P < 0.01) and p38‐mitogen‐activated protein kinase (MAPK) (~4.2‐fold, P < 0.01) occurred immediately in both exercises and to a greater extent after the intermittent exercise (condition x time interaction, P < 0.05). A single bout of intermittent exercise induces a greater activation of these signaling pathways regulating PGC‐1α when compared to a single bout of continuous exercise of matched work and intensity. Chronic adaptations to exercise on mitochondria biogenesis are yet to be investigated.

Direct-to-consumer genetic testing for predicting sports performance and talent identification: Consensus statement.

The general consensus among sport and exercise genetics researchers is that genetic tests have no role to play in talent identification or the individualised prescription of training to maximise performance. Despite the lack of evidence, recent years have witnessed the rise of an emerging market of direct-to-consumer marketing (DTC) tests that claim to be able to identify childrens athletic talents. Targeted consumers include mainly coaches and parents. There is concern among the scientific community that the current level of knowledge is being misrepresented for commercial purposes. There remains a lack of universally accepted guidelines and legislation for DTC testing in relation to all forms of genetic testing and not just for talent identification. There is concern over the lack of clarity of information over which specific genes or variants are being tested and the almost universal lack of appropriate genetic counselling for the interpretation of the genetic data to consumers. Furthermore independent studies have identified issues relating to quality control by DTC laboratories with different results being reported from samples from the same individual. Consequently, in the current state of knowledge, no child or young athlete should be exposed to DTC genetic testing to define or alter training or for talent identification aimed at selecting gifted children or adolescents. Large scale collaborative projects, may help to develop a stronger scientific foundation on these issues in the future.