Injuries in 13 international Athletics championships between 2007–2012

Muscle injuries in athletics during the 2020 Tokyo Olympic Games: differences between heats and finals

BACKGROUND

The aim of this study was to analyze muscle injuries and their related risk factors during the Athletics events of the 2020 Tokyo Olympic Games including the differences in muscle injury rates between heats and finals.

METHODS

We included and analyzed in this study muscle injuries diagnosed by either magnetic resonance imaging, ultrasound, or physical examinations by at least two physicians, from Athletics athletes participating at the 2020 Tokyo Olympic Games. Data from electronic medical records, including sex, nationality, event, and the round (heat vs. final) during which the muscle injury occurred and the air temperature in the stadium, measured every five minutes during the competition were extracted.

RESULTS

Among the 1631 athletes who competed, a total of 36 athletes (20 males and 16 females) were diagnosed with a muscle injury during the 2020 Tokyo Olympic Games. Among them, 24 occurred during heats (1.47 per 100 athletes) and 12 during finals (2.20 per 100 athletes) (P=0.25). Logistic regression analysis revealed that the geographic region of athletes' origin was a factor associated with muscle injury, with the highest muscle injury rate being in athletes from Africa (odds ratio [OR]=4.74, 95% confidence interval [CI]) = 1.75 to 12.82) and North America (OR=3.02, 95%CI=1.27 to 7.20). For male athletes, competing in finals was a risk factor to sustain a muscle injury (OR=2.55, 95%CI=1.01 to 6.45).

CONCLUSIONS

During the 2020 Olympic Games, muscle injury rate was higher in finals than in heats, reaching statistical significance in male athletes.

Do we underestimate the frequency of ankle sprains in running? A systematic review and meta-analysis

OBJECTIVE

To provide a systematic review and meta-analysis of the proportion of ankle sprains in running practices.

DESIGN

Systematic review and meta-analysis.

MAIN OUTCOME MEASURES

We calculated the weighted summary proportion and conducted meta-analyses for runners, considering levels (elite/recreational) and disciplines (distance, track, cross-country, trail, and orienteering).

RESULTS

32 studies were included in the systematic review and 19 were included in the meta-analysis with a level of quality ranging from poor to good. Proportion of ankle sprains in runners was 13.69% (95%CI = 7.40-21.54; I2 = 98.58%) in global, 12.20% (95%CI = 5.24-21.53; I2 = 89.31%) in elite, 19.40% (95%CI = 10.05-30.90; I2 = 99.09%) in recreational, 8.51% (95%CI = 4.22-14.12; I2 = 96.15%) in distance, 67.42% (95%CI = 0.50-82.85; I2 = 99.36%) in track, 27.07% (95%CI = 12.48-44.81; I2 = 97.97%) in cross-country, and 25.70% (95%CI = 19.87-32.14; I2 = 0.00) in orienteering.

CONCLUSIONS

Running practice results in significant proportion rate of ankle sprains. Recreational runners exhibit higher proportion than elite. Running disciplines, especially track, cross-country, and orienteering, influence reported ankle sprain rates, surpassing those of distance runners.

Epidemiology of bone injuries in elite athletics: A prospective 9-year cohort study

OBJECTIVES

To describe bone injury patterns in elite track and field athletes. To investigate relationships between bone injury and athlete characteristics to inform future injury prevention strategies.

DESIGN

Descriptive epidemiology study.

SETTING

Elite athletics training centres across the United Kingdom and internationally, observed between 2012 and 2020.

PARTICIPANTS

207 Olympic programme senior track and field athletes.

MAIN OUTCOME MEASURES

Injury number, Incidence, Severity, Burden, Time Loss.

RESULTS

There were 78 fractures during the study period. Gradual repetitive bone injuries were the most common type of injury mode. The foot, pelvis and the lumbar spine were the regions with the highest number of bone stress injuries. Stress fractures had a higher burden overall compared to stress reactions. Average return to full training was 67.4 days (±73.1) for stress reactions and 199 (±205.2) days for stress fractures. There was no relationship between bone injury type and age, sex, ethnicity, side dominance or event group.

CONCLUSION

Bone stress injuries in athletics have a high severity and burden warranting continued efforts to prevent their occurrence and optimize management. Age, sex, ethnicity, side dominance and event region do not have any relationship with bone injury occurrence and are therefore unlikely to increase risk in this cohort.

Risk factors for injury complaints leading to restricted participation in Athletics (Track and Field): a secondary analysis of data from 320 athletes over one season

OBJECTIVE

To investigate if several potential risk factors were associated with time to injury complaints leading to participation restriction in Athletics (ICPR).

METHODS

We performed a secondary analysis of data collected during 39 weeks of the 2017-2018 Athletics season in a cluster-randomised controlled trial ('PREVATHLE'). Univariate and multivariable analyses using Cox regression models were performed to analyse the association between the time to first ICPR and potential risk factors collected (1) at baseline: sex, age, height, body mass, discipline, the usual duration of Athletics training and non-specific sports training, ICPR in the preceding season (yes/no), ICPR at baseline (yes/no); (2) weekly during the season: duration and intensity of Athletics training and competition, and non-specific sports training, fitness subjective state, sleep duration and illness (yes/no); and (3) combined.

RESULTS

Data from 320 athletes were included; 138 (43.1%) athletes reported at least one ICPR during the study follow-up. The combined multivariable analyses revealed that the risk of ICPR at any given time was significantly higher in athletes with a pre-existing ICPR (hazard rate ratio, HRR 1.90, 95% CI 1.15 to 3.15; p=0.012) and lower in athletes with a higher fitness subjective state (HRR 0.63, 95% CI 0.55 to 0.73; p<0.001) and who had had at least one illness during the season (HRR 0.42, 95% CI 0.29 to 0.62; p<0.001).

CONCLUSIONS

Our results provide new insights into injury risk factors in Athletics that could help with potential injury risk reduction strategies. These could be to explore the pre-existing injury presence at the season's beginning and to monitor the fitness subjective state and illnesses occurrence during the season.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03307434.

Swedish Olympic athletes report one injury insurance claim every second year: a 22-year insurance registry-based cohort study

PURPOSE

To describe injury incidence, time trends in injury incidence, and injury characteristics among Swedish Olympic athletes over 22 years based on insurance data, as a first step to inform injury preventive measures among Olympic athletes.

METHODS

The cohort comprised 762 elite athletes (54% males; age 26.5 ± 5.9 years) in 38 sports in the Swedish Olympic Committee support program 'Top and Talent' between 1999 and 2020, with total 3427 athlete-years included. Acute and gradual onset injuries were reported to the insurance registry by the athletes' medical staff.

RESULTS

A total of 1635 injuries in 468 athletes were registered. The overall injury incidence was 47.7 injuries/100 athlete-years (one injury per athlete every second year). An increasing trend in injury incidence was observed in the first decade 2001 to 2010 (annual change 6.0%, 95% CI 3.3-8.8%), while in the second decade 2011 to 2020 no change was evident (0.4%, 95% CI - 1.9 to 2.7%). Gymnastics, tennis, and athletics had the highest incidence (100.0, 99.3, and 93.4 injuries/100 athlete-years, respectively). Among sport categories, mixed and power sports had the highest incidence (72.8 and 69.5 injuries/100 athlete-years, respectively). Higher incidences were seen in the younger age groups (≤ 25 years) in mixed and skill sports. The injury incidence was comparable between male and female athletes, and summer and winter sports. Most injuries occurred in the lower limb, and specifically the knee (24%), foot/ankle (15%) and spine/pelvis (13%).

CONCLUSION

The results on injury patterns in different sports and age groups may guide preventive focus for health and performance teams working with Olympic athletes.

LEVEL OF EVIDENCE

II.

"Biofeedback-based return to sport": individualization through objective assessments

Elite athletes are regularly exposed to high and repetitive mechanical stresses and impacts, resulting in high injury rates. The consequences of injury can range from time lost from training and competition to chronic physical and psychological burden, with no guarantee that the athlete will return to preinjury levels of sport activity and performance. Prominent predictors include load management and previous injury, highlighting the importance of the postinjury period for effective return to sport (RTS). Currently, there is conflicting information on how to choose and assess the best reentry strategy. Treating RTS as a continuum, with controlled progression of training load and complexity, seems to provide benefits in this process. Furthermore, objectivity has been identified as a critical factor in improving the effectiveness of RTS. We propose that assessments derived from biomechanical measurements in functional settings can provide the objectivity needed for regular biofeedback cycles. These cycles should aim to identify weaknesses, customize the load, and inform on the status of RTS progress. This approach emphasizes individualization as the primary determinant of RTS and provides a solid foundation for achieving it.

Epidemiology of MRI-detected muscle injury in athletes participating in the Tokyo 2020 Olympic Games

OBJECTIVE

Muscle injury is one of the most common injuries occurring at the Olympic Games often with devastating consequences. Epidemiological injury surveillance is recognised by the IOC as essential for injury prevention and management. We aimed to describe the incidence, anatomical location and classification of MRI-detected muscle injuries in athletes who participated in the Tokyo 2020 Olympic Games.

METHODS

Two board-certified orthopaedic surgeons, highly experienced in reviewing MRIs, independently and retrospectively reviewed all MRIs collected at the Tokyo 2020 Olympic Games from clinical reports generated by board-certified musculoskeletal radiologists at the IOC Polyclinic. The presence and anatomical site of muscle injuries were classified as: type a: myofascial/peripheral; type b: muscle belly or musculotendinous junction; and type c: injury which extends into the tendon, with reference to the British Athletics Muscle Injury Classification.

RESULTS

Fifty-nine MRI-detected muscle injuries were seen in 40 male and 19 female athletes. 24 athletes (41%) were unable to fully compete in their event. Fifty-two injuries (88%) involved lower extremity muscles with hamstring muscle injuries most common (32 of 59, 54%). Half of all muscle injuries occurred in athletes participating in athletics (30 of 59, 51%). 21 athletes (35%) sustained type a injuries, 14 athletes (24%) type b injuries and 24 athletes (41%) type c injuries. Of athletes with type c injuries, 18 (75%) did not complete their competition, a rate significantly higher than types a and b (OR 14.50, 95% CI 4.0 to 51.9, p<0.001).

CONCLUSION

For athletes sustaining muscle injuries during the Olympic Games, our study demonstrates the prognostic relevance of muscle injury anatomical site and severity for predicting completion or non-completion of an Olympic athlete's competition.

Associations of time to return to performance following acute posterior thigh injuries with running biomechanics, hamstring function, and structure in collegiate sprinters: A prospective cohort design

BACKGROUND

The time to return to sport from acute hamstring strain injuries is associated with several functional and structural impairments. However, not all previous studies assessed the preinjury level before acute hamstring strain injuries directly. The purpose of this study was to examine the associations of the time to return to performance following acute hamstring strain injuries with deficits in running biomechanics, hamstring function and structure in collegiate sprinters by a prospective study.

METHODS

Using a prospective cohort design, 72 participants were recruited from a collegiate track and field team. At the preinjury assessment, a 60-m running-specific test, passive straight leg raise test and isometric knee flexion strength test were assessed at the beginning of the competitive season for three consecutive years (2017-2019). Afterwards, postinjury examinations were performed only in sprinters with acute hamstring strain injuries.

FINDINGS

Twelve sprinters strained their hamstring muscle (incidence rate of hamstring strain injuries: 16.7%); the majority (n = 10) were classified as grades 0-2. The running speed deficit of the running-specific test was associated with the time to return to performance as well as the passive straight leg raise test deficit. In the running-specific test, lower-limb kinetic deficits were more strongly associated with the time to return to performance compared to lower-limb kinematic deficits.

INTERPRETATION

A running-specific test may be considered one of the most convenient and valid tests for assessing rehabilitation progress after acute hamstring strain injuries.

Short-Term Carbohydrate Restriction Impairs Bone Formation at Rest and During Prolonged Exercise to a Greater Degree than Low Energy Availability

Bone stress injuries are common in athletes, resulting in time lost from training and competition. Diets that are low in energy availability have been associated with increased circulating bone resorption and reduced bone formation markers, particularly in response to prolonged exercise. However, studies have not separated the effects of low energy availability per se from the associated reduction in carbohydrate availability. The current study aimed to compare the effects of these two restricted states directly. In a parallel group design, 28 elite racewalkers completed two 6-day phases. In the Baseline phase, all athletes adhered to a high carbohydrate/high energy availability diet (CON). During the Adaptation phase, athletes were allocated to one of three dietary groups: CON, low carbohydrate/high fat with high energy availability (LCHF), or low energy availability (LEA). At the end of each phase, a 25-km racewalk was completed, with venous blood taken fasted, pre-exercise, and 0, 1, 3 hours postexercise to measure carboxyterminal telopeptide (CTX), procollagen-1 N-terminal peptide (P1NP), and osteocalcin (carboxylated, gla-OC; undercarboxylated, glu-OC). Following Adaptation, LCHF showed decreased fasted P1NP (~26%; p < 0.0001, d = 3.6), gla-OC (~22%; p = 0.01, d = 1.8), and glu-OC (~41%; p = 0.004, d = 2.1), which were all significantly different from CON (p < 0.01), whereas LEA demonstrated significant, but smaller, reductions in fasted P1NP (~14%; p = 0.02, d = 1.7) and glu-OC (~24%; p = 0.049, d = 1.4). Both LCHF (p = 0.008, d = 1.9) and LEA (p = 0.01, d = 1.7) had significantly higher CTX pre-exercise to 3 hours post-exercise but only LCHF showed lower P1NP concentrations (p < 0.0001, d = 3.2). All markers remained unchanged from Baseline in CON. Short-term carbohydrate restriction appears to result in reduced bone formation markers at rest and during exercise with further exercise-related increases in a marker of bone resorption. Bone formation markers during exercise seem to be maintained with LEA although resorption increased. In contrast, nutritional support with adequate energy and carbohydrate appears to reduce unfavorable bone turnover responses to exercise in elite endurance athletes. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Three-dimensional turbo spin-echo (TSE) MRI assessment of indirect acute muscle injuries in athletes: comparison with two-dimensional TSE MRI

OBJECTIVE

To evaluate three-dimensional (3D) turbo spin-echo (TSE) magnetic resonance imaging (MRI) for the assessment of acute muscle injuries in elite athletes in comparison with two-dimensional (2D) MRI.

METHODS

Elite athletes with clinically suspected acute muscle injury of the thigh who underwent both 2D and 3D MRI protocols on the same day were retrospectively included. Two musculoskeletal radiologists independently assessed 2D and 3D MRIs, with both techniques evaluated separately 1-month apart. Muscle injuries were evaluated using the BAMIC and the INSEP classifications. A second assessment of injuries was performed by each reader 2 months after the initial readings. Agreement was determined using weighted kappa statistics. The level of diagnostic confidence in classifying injuries was also assessed for both MRI protocols.

RESULTS

A total of 40 athletes were included. Intra-reader agreement when comparing injury grades from 2D vs. 3D for both INSEP and BAMIC classifications was almost perfect for both readers and ranged between 0.84 and 0.98. Inter-reader agreement was substantial to almost perfect and ranged from 0.78 to 0.93 for the 2D protocol, and from 0.78 to 0.95 for the 3D protocol. Intra-reader agreement for each MRI protocol separately was almost perfect to perfect for both readers and ranged between 0.84 and 1.00. Diagnostic confidence for grading injuries improved for both readers when using the 3D protocol.

CONCLUSIONS

Compared to 2D MRI, 3D TSE MRI is a reliable technique for acute muscular injury assessment, providing faster acquisition times and improving the diagnostic confidence.

KEY POINTS

• Compared to 2D MRI, 3D TSE MRI is a reliable technique for the assessment of acute muscular injuries. • 3D TSE MRI has the advantage of faster total acquisition times, thinner sections, and multiplanar reconstruction, improving the confidence for structural assessment including connective tissue involvement.

Time to return to full training and recurrence of rectus femoris injuries in elite track and field athletes 2010-2019; a 9-year study using the British Athletics Muscle Injury Classification

Rectus femoris (RF) injuries are common in sports requiring maximal acceleration and sprinting. The British Athletics Muscle Injury Classification (BAMIC) describes acute muscle injury based on the anatomical site of injury and has been associated with return to play in hamstring and calf muscle injury. The aim of this study was to describe and compare the time to return to full training (TRFT) and injury recurrence for BAMIC-classified RF injuries sustained by elite track and field (T&F) athletes over a 9-year period. All rectus femoris injuries sustained by elite T&F athletes on the British Athletics World Class Program between September 2010 and September 2019 that were investigated with an MRI within 7 days of acute onset anterior thigh pain were included. Injuries were graded from the MRI by a specialist musculoskeletal radiologist using the BAMIC, and TRFT and injury recurrence were determined by evaluation of the Electronic Medical Record. Athlete demographics and World Athletics event discipline were recorded. Specific injury details including mechanism, location of injury, and whether surgical or rehabilitation management was undertaken were recorded. There were 38 RF injuries in 27 athletes (24.7 ± 2.3 years; 10 male, 17 female). Average TRFT for rehabilitation managed cases was 20.4 ± 14.8 days. Grade 1 injuries had significantly shorter TRFT compared with grades 2 (p = 0.04) and 3 (p = 0.01). Intratendinous (c) and surgically managed RF injuries each had significantly longer TRFT compared with other injury classes (p < 0.001). Myofascial (a) injuries had reduced repeat injury rates compared with b or c classes (p = 0.048). Grade 3 injuries had an increased repeat injury rate compared with other grades (p = 0.02). There were 4 complete (4c) proximal free tendon injuries sustained during sprinting and all in female athletes. The average TRFT for RF injuries in elite T&F is similar to that previously identified in elite football and Australian Rules. Similar to previous research in hamstring and calf injury, RF injuries extending into the tendon (BAMIC class c) had delayed TRFT which may reflect the longer duration required for tendon healing and adaptation. Grade 3 injuries had in increased repeat injury rate compared with grades 1 and 2. The BAMIC diagnostic framework may provide useful information for clinicians managing rectus femoris injuries in T&F.

The Key Role of Nutritional Elements on Sport Rehabilitation and the Effects of Nutrients Intake

Adequate nutrition is of utmost importance for athletes, especially during rehabilitation after injury in order to achieve fast healing and return to sports. The aim of this narrative review is to define the proper nutritional elements for athletes to meet their needs and facilitate their fast return to sports after surgery or injury, as well as determine the effects of specific nutrients intake. Studies on antioxidants, which are substances that protect against free radicals, for the injured athlete are few and unclear, yet poly-phenols and especially flavonoids might improve healing and inflammation following an injury. Benefits of vitamin C or E on muscle damage are disputable in relevant studies, while optimal levels of vitamin D and calcium contribute to bone healing. Minerals are also essential for athletes. Other supplements suggested for muscle damage treatment and protein synthesis include leucine, creatine, and hydroxymethylbutyrate. Diets that include high-quality products, rich in micronutrients (like vitamins, minerals, etc.) bio-active compounds and other nutritional elements (like creatine) are suggested, while an individualized nutrition program prescribed by a trained dietitian is important. Further studies are needed to clarify the underlying mechanisms of these nutritional elements, especially regarding injury treatment.

Return to Play Prediction Accuracy of the MLG-R Classification System for Hamstring Injuries in Football Players: A Machine Learning Approach

BACKGROUND AND OBJECTIVE

Muscle injuries are one of the main daily problems in sports medicine, football in particular. However, we do not have a reliable means to predict the outcome, i.e. return to play from severe injury. The aim of the present study was to evaluate the capability of the MLG-R classification system to grade hamstring muscle injuries by severity, offer a prognosis for the return to play, and identify injuries with a higher risk of re-injury. Furthermore, we aimed to assess the consistency of our proposed system by investigating its intra-observer and inter-observer reliability.

METHODS

All male professional football players from FC Barcelona, senior A and B and the two U-19 teams, with injuries that occurred between February 2010 and February 2020 were reviewed. Only players with a clinical presentation of a hamstring muscle injury, with complete clinic information and magnetic resonance images, were included. Three different statistical and machine learning approaches (linear regression, random forest, and eXtreme Gradient Boosting) were used to assess the importance of each factor of the MLG-R classification system in determining the return to play, as well as to offer a prediction of the expected return to play. We used the Cohen's kappa and the intra-class correlation coefficient to assess the intra-observer and inter-observer reliability.

RESULTS

Between 2010 and 2020, 76 hamstring injuries corresponding to 42 different players were identified, of which 50 (65.8%) were grade 3^r, 54 (71.1%) affected the biceps femoris long head, and 33 of the 76 (43.4%) were located at the proximal myotendinous junction. The mean return to play for grades 2, 3, and 3^r injuries were 14.3, 12.4, and 37 days, respectively. Injuries affecting the proximal myotendinous junction had a mean return to play of 31.7 days while those affecting the distal part of the myotendinous junction had a mean return to play of 23.9 days. The analysis of the grade 3^r biceps femoris long head injuries located at the free tendon showed a median return to play time of 56 days while the injuries located at the central tendon had a shorter return to play of 24 days (p = 0.038). The statistical analysis showed an excellent predictive power of the MLG-R classification system with a mean absolute error of 9.8 days and an R-squared of 0.48. The most important factors to determine the return to play were if the injury was at the free tendon of the biceps femoris long head or if it was a grade 3^r injury. For all the items of the MLG-R classification, the intra-observer and inter-observer reliability was excellent (k > 0.93) except for fibres blurring (κ = 0.68).

CONCLUSIONS

The main determinant for a long return to play after a hamstring injury is the injury affecting the connective tissue structures of the hamstring. We developed a reliable hamstring muscle injury classification system based on magnetic resonance imaging that showed excellent results in terms of reliability, prognosis capability and objectivity. It is easy to use in clinical daily practice, and can be further adapted to future knowledge. The adoption of this system by the medical community would allow a uniform diagnosis leading to better injury management.

Injury and Illness in Elite Athletics: A Prospective Cohort Study Over Three Seasons

Background

Athletics (also known as track and field) is one of the most popular sports in the world and is the centrepiece of the Summer Olympic Games. Participation in athletics training and competition involves a risk of illness and injury.

Purpose

To describe injury and illness in British Olympic track and field athletes over three full training and competition seasons.

Study Design

Descriptive Epidemiology Study.

Methods

A total of 111 athletes on the British national program were followed prospectively for three consecutive seasons between 2015-2018. Team medical personnel recorded all injuries and illnesses during this time, following current consensus-based methods. All data pertaining to these records were reviewed and analyzed for sports injury and illness epidemiological descriptive statistics.

Results

The average age of the athletes was 24 years for both males and females (24 years, +/- 4). Total exposure for the three seasons was 79 205 athlete days (217 athlete years). Overuse injuries (56.4%) were more frequent than acute injuries (43.6%). The thigh was the most common injury location (0.6 per athlete year), followed by the lower leg (0.4 per athlete year) and foot (0.3 per athlete year). Muscle and tendon were the most commonly injured tissues, while strains and tears were the most common pathology type. Hamstring muscle strain was the most common diagnosis causing time loss, followed by Achilles tendinopathy and soleus muscle strain. Respiratory illness was the most common illness type (0.3 per athlete year).

Conclusion

Hamstring strains, Achilles tendinopathy, and soleus strains are the most common injuries in athletics and have highest burden. Respiratory illness is the most common illness and has the highest burden. Knowledge of this injury and illness profile within athletics could be utilised for the development of targeted prevention measures within the sport at the elite level.

Level of Evidence

3.

Epidemiology of injuries in track and field athletes: a cross-sectional study of specific injuries based on time loss and reduction in sporting level

OBJECTIVES

To prevent the occurrence of injury in a sport, exact knowledge of injury patterns is needed. To synthesize sport-specific injuries in track and field comparing elite and recreational level athletes, as well as gender. Furthermore, analyze the time loss due to injury and reduction in athletic performance.

METHODS

Injury type-specific frequencies were recorded according to discipline, gender and performance level. Injury severity was assessed by time loss duration and performance reduction.

RESULTS

64% of athletes suffered at least one injury. In the top 10 ranking, 83% (n = 524) were located in the lower extremities. A muscle strain of the thigh had the highest prevalence in sprint (34%, n = 41), jump (15%, n = 15) and middle-distance running (16%, n = 6). More injuries occurred during training (75%, n = 165) as compared to competition (25%, n = 56). The longest time loss was documented in throwing with a downtime of 36 weeks after a ligament injury of the elbow and 39 weeks after a muscle injury of the elbow. The injury with the highest number of athletes with a reduced level of performance was the foot ligament injury in sprint athletes at 100%.

CONCLUSION

Assessing time loss and performance reduction in athletics, there are discipline-specific injury patterns. This study points out the high prevalence of training injuries, highlighting the need for future investigations to adapt training management, improve medical care and rehabilitation with respect to every discipline.

Injury patterns among national-level athletes in Lebanon: a retrospective study

Objectives:This study aims to assess the annual prevalence, associated factors, and characteristics of musculoskeletal disorders among Lebanese national-level athletes.Methods: Lebanese athletes aged 18 and over and who competed in a top-level national championship during an entire athletics season were invited to participate in the study. Data were collected through questionnaire assessing self-reported injury during the past year. Injury, dependent variable of the study, was defined as a musculoskeletal condition that made the athlete partially or completely abstains from training or competition for a 1-week minimum injury period.Results: Among the 250 eligible athletes, 210 (84.0%) (25.5±6.7 years) completed the questionnaire. The 1-year retrospective injury prevalence was 51.9% (95% confidence interval, 45.1%-58.7%). Injured athletes reported 150 injuries: 128 (85.3%) affected the lower extremities, and 111 (74.0%) occurred during training. The most common type was muscle cramps/spasm (n=53; 35.3%); and overuse (n=121; 80.7%) was the predominant cause. Athletes who mainly practiced endurance disciplines (-p-value=0.042), who participated in international athletics championships (-p-value=0.047), and who were taking chronic medications (-p-value=0.049) had more injuries in the past year.Conclusion: These findings may help inform potential injury prevention programs, which should target injuries affecting the lower extremities, and consider the factors associated with injury risk among Lebanese athletes.

Lower limb muscle injury location shift from posterior lower leg to hamstring muscles with increasing discipline-related running velocity in international athletics championships

OBJECTIVE

To analyse the rates of lower limb muscle injuries in athletics disciplines requiring different running velocities during international athletics championships.

DESIGN

Prospective total population study.

METHODS

During 13 international athletics championships (2009-2019) national medical teams and local organizing committee physicians daily reported all newly incurred injuries using the same study design, injury definition and data collection procedures. In-competition lower limb muscle injuries of athletes participating in disciplines involving running (i.e. sprints, hurdles, jumps, combined events, middle distances, long distances, and marathon) were analysed.

RESULTS

Among the 12,233 registered athletes, 344 in-competition lower limb muscle injuries were reported (36% of all in-competition injuries). The proportion, incidence rates and injury burden of lower limb muscles injuries differed between disciplines for female and male athletes. The most frequently injured muscle group was hamstring in sprints, hurdles, jumps, combined events and male middle distances runners (43-75%), and posterior lower leg in female middle distances, male long distances, and female marathon runners (44-60%). Hamstring muscles injuries led to the highest burden in all disciplines, except for female middle distance and marathon and male long distance runners. Hamstring muscles injury burden was generally higher in disciplines requiring higher running velocities, and posterior lower leg muscle injuries higher in disciplines requiring lower running velocities.

CONCLUSIONS

The present study shows discipline-specific injury location in competition context. Our findings suggest that the running velocity could be one of the factors that play a role in the occurrence/location of muscle injuries.

Why Are Masters Sprinters Slower Than Their Younger Counterparts? Physiological, Biomechanical, and Motor Control Related Implications for Training Program Design

Elite sprint performances typically peak during an athlete's 20s and decline thereafter with age. The mechanisms underpinning this sprint performance decline are often reported to be strength-based in nature with reductions in strength capacities driving increases in ground contact time and decreases in stride lengths and frequency. However, an as-of-yet underexplored aspect of Masters sprint performance is that of age-related degradation in neuromuscular infrastructure, which manifests as a decline in both strength and movement coordination. Here, the authors explore reductions in sprint performance in Masters athletes in a holistic fashion, blending discussion of strength and power changes with neuromuscular alterations along with mechanical and technical age-related alterations. In doing so, the authors provide recommendations to Masters sprinters-and the aging population, in general-as to how best to support sprint ability and general function with age, identifying nutritional interventions that support performance and function and suggesting useful programming strategies and injury-reduction techniques.

Athlete health and safety at large sporting events: the development of consensus-driven guidelines

All sport events have inherent injury and illness risks for participants. Healthcare services for sport events should be planned and delivered to mitigate these risks which is the ethical responsibility of all sport event organisers. The objective of this paper was to develop consensus-driven guidelines describing the basic standards of services necessary to protect athlete health and safety during large sporting events. By using the Knowledge Translation Scheme Framework, a gap in International Federation healthcare programming for sport events was identified. Event healthcare content areas were determined through a narrative review of the scientific literature. Content experts were systematically identified. Following a literature search, an iterative consensus process was undertaken. The outcome document was written by the knowledge translation expert writing group, with the assistance of a focus group consisting of a cohort of International Federation Medical Chairpersons. Athletes were recruited to review and provide comment. The Healthcare Guidelines for International Federation Events document was developed including content-related to (i) pre-event planning (eg, sport medical risk assessment, public health requirements, environmental considerations), (ii) event safety (eg, venue medical services, emergency action plan, emergency transport, safety and security) and (iii) additional considerations (eg, event health research, spectator medical services). We developed a generic standardised template guide to facilitate the planning and delivery of medical services at international sport events. The organisers of medical services should adapt, evaluate and modify this guide to meet the sport-specific local context.

Injury characteristics in male youth athletics: a five-season prospective study in a full-time sports academy

OBJECTIVES

To describe the injury characteristics of male youth athletes exposed to year-round athletics programmes.

METHODS

Injury surveillance data were prospectively collected by medical staff in a cohort of youth athletics athletes participating in a full-time sports academy from 2014-2015 to 2018-2019. Time-loss injuries (>1 day) were recorded following consensus procedures for athletics. Athletes were clustered into five event groups (sprints, jumps, endurance, throws and non-specialised) and the number of completed training and competition sessions (athletics exposures (AE)) were calculated for each athlete per completed season (one athlete season). Injury characteristics were reported overall and by event groups as injury incidence (injuries per 1000 AE) and injury burden (days lost per 1000 AE).

RESULTS

One-hundred and seventy-eight boys (14.9±1.8 years old) completed 391 athlete seasons, sustaining 290 injuries. The overall incidence was 4.0 injuries per 1000 AE and the overall burden was 79.1 days lost per 1000 AE. The thigh was the most common injury location (19%). Muscle strains (0.7 injuries per 1000 AE) and bone stress injuries (0.5 injuries per 1000 AE) presented the highest incidence and stress fractures the highest burden (17.6 days lost per 1000 AE). The most burdensome injury types by event group were: bone stress injuries for endurance, hamstring strains for sprints, stress fractures for jumps, lesion of meniscus/cartilage for throws and growth plate injuries for non-specialised athletes.

CONCLUSION

Acute muscle strains, stress fractures and bone stress injuries were identified as the main injury concerns in this cohort of young male athletics athletes. The injury characteristics differed between event groups.

Implementation of Injury and Illness Surveillance Protocols in Varsity Athletes

OBJECTIVE

To develop and implement a prospective varsity athlete surveillance system to identify injury and illness trends in a multisport varsity-level university setting.

DESIGN

Longitudinal prospective surveillance study.

SETTING

Varsity-level sport program at the University of Guelph, Guelph, ON, Canada.

PARTICIPANTS

Athletic therapists (ATs) (n = 35) from 17 varsity sports provided injury and illness information on 624 varsity-level athletes (381 men and 243 women) during the 2016/2017 competitive season.

INTERVENTIONS

Team ATs reported athlete health complaints weekly. Athletes reported additional details on the injury or illness that was reported.

MAIN OUTCOME MEASURES

The outcome measurements included when the injury or illness occurred, anatomical location, diagnosis, cause, perceived severity, treatment, estimated athlete exposure (AE) to training and competition, and time loss from sport. Measures were recorded from the teams' first competition through to the end the season and/or playoffs.

RESULTS

Twenty-nine of 30 varsity sports teams participated in this injury and illness surveillance protocol. The compliance of team ATs and varsity athletes was 89% (men: 94%, women: 82%). The overall injury and illness rates were 5.5 injuries and 1.7 illnesses per 1000 AEs, respectively. Men's injury rates were greater than women's, and injury rates of contact sports were greater than noncontact sports.

CONCLUSIONS

The utilization of a prospective injury and illness surveillance protocol in the Canadian University sport system is feasible with good athlete, AT, and coach acceptance. The surveillance data should inform future injury and illness prevention strategies.

Intramuscular Injection of Combined Calf Blood Compound (CFC) and Homeopathic Drug Tr14 Accelerates Muscle Regeneration In Vivo

Skeletal muscle injuries in competitive sports cause lengthy absences of athletes from tournaments. This is of tremendous competitive and economic relevance for both the athletes and their respective clubs. Therapy for structural muscle lesions aims to promote regeneration and fast-track return-to-play. A common clinical treatment strategy for muscle injuries is the intramuscular injection of calf blood compound and the homeopathic drug, Tr14. Although the combination of these two agents was reported to reduce recovery time, the regulatory mechanism whereby this occurs remains unknown. In this in vivo study, we selected a rat model of mechanical muscle injury to investigate the effect of this combination therapy on muscle regeneration. Gene expression analysis and histological images revealed that this combined intramuscular injection for muscle lesions can enhance the expression of pro-myogenic genes and proteins and accelerate muscle regeneration. These findings are novel and depict the positive effects of calf blood compound and the homeopathic drug, Tr14, which are utilized in the field of Sports medicine.

Injury frequency and characteristics (location, type, cause and severity) differed significantly among athletics ('track and field') disciplines during 14 international championships (2007-2018): implications for medical service planning

OBJECTIVE

To analyse differences between athletic disciplines in the frequency and characteristics of injuries during international athletics championships.

METHODS

Study design, injury definition and data collection procedures were similar during the 14 international championships (2007-2018). National medical teams and local organising committee physicians reported all newly incurred injuries daily on a standardised injury report form. Results were presented as number of injuries and number of injuries per 1000 registered athletes, separately for male and female athletes, and for each discipline.

RESULTS

From a total of 8925 male and 7614 female registered athletes, 928 injuries were reported in male and 597 in female athletes. The discipline accounting for the highest proportion of injuries was sprints, for both men (24%) and women (26%). The number of injuries per 1000 registered athletes varied between disciplines for men and women: highest in combined events for male athletes (235 (95% CI 189 to 281)) and female athletes (212 (95% CI 166 to 257)), and lowest for male throwers (47 (95% CI 35 to 59)) and female throwers (32 (95% CI 21 to 43)) and for female race walkers (42 (95% CI 19 to 66)). Injury characteristics varied significantly between disciplines for location, type, cause and severity in male and female athletes. Thigh muscle injuries were the main diagnoses in the disciplines sprints, hurdles, jumps, combined events and race walking, lower leg muscle injuries in marathon running, lower leg skin injury in middle and long distance running, and trunk muscle and lower leg muscle injuries in throws.

CONCLUSIONS

Injury characteristics differed substantially between disciplines during international athletics championships. Strategies for medical service provision (eg, staff, facilities) during athletics championships should be discipline specific and be prepared for targeting the main injuries in each discipline.

A One-Season Prospective Study of Illnesses, Acute, and Overuse Injuries in Elite Youth and Junior Track and Field Athletes

Background: In high-level adult athletes, injury incidences and characteristics have been reported during international championships and during one season. Youth track and field athletes are also exposed to injury risk, although less information is available on this specific population, as well as on illness risk.

Aim: To determine the prevalence of health problems (i.e., illnesses, acute, and overuse injuries) in high level Youth and Junior Track & Field athletes.

Method: During the 2015–16 athletics season (30 weeks from December 2015 to July 2016), we conducted a prospective cohort study on a population of Youth and Junior Irish national level athletes, during which athletes were asked to complete a weekly web-based questionnaire (Oslo Sports Trauma Research Center questionnaire on health problems) regarding their health problems.

Results: A total of 70 athletes participated (37 male and 33 female athletes), with an average weekly response rate of 71%. The average weekly prevalence for all athletes was 27% (95%CI 17 to 38%) for all health problems, and 11% (95%CI 3 to 18%) for substantial health problems. Average prevalence varied significantly between endurance and explosive disciplines: a higher prevalence of all and substantial health problems and all and substantial overuse injuries was found in endurance disciplines. A higher prevalence of acute injuries was found in explosive disciplines. Characteristics of acute and overuse injuries differed according to sex and discipline: hamstring strain/cramps/spasms was the main injuries in explosive disciplines, and knee tendinopathy and lower leg strain/cramp/spasms in endurance disciplines, trunk cramps/spasms being frequent in both disciplines. Upper respiratory tract problems were the most commonly reported illnesses regardless of sex and disciplines.

Conclusion: This study provides important information regarding the extent of health problem in Youth and Junior track and field athletes. This could help orient injury prevention measures. For injuries, it should be focused on muscle injuries, especially located on the hamstring, calf, and trunk. For illness, prevention measures could include: screening tests for airway problems, but also general illness prevention measures (e.g., drinking regularly, eating “safe” food, regular hand washing, decreasing contact with sick people, avoiding dehydration).

Ten Tips to Hurdle the Injuries and Illnesses During Major Athletics Championships: Practical Recommendations and Resources

Participating or winning a medal in major track and field (athletics) competitions is the goal of every athlete. However, health problems can impair sports performance and affect this dream. Therefore, we present ten tips to help hurdle the challenges of illness/injury at major athletics championships: (1) Prepare for travel (medical checking, vaccine, time-zone, jet lag, culture, food habits…), (2) Respect athlete characteristics and discipline specificity (sex, endurance/explosive), (3) Educate athletes and their entourages regarding prevention, (4) Vigilance of painful symptoms and subclinical illness markers, (5) Avoid infection risk (washing hands, safe food and drink, avoid contact with sick people…), (6) Train appropriately and optimally (physical conditioning, technical training, load management, and psychological preparation), (7) Health status (history of previous injuries, well-being in the month before championships), (8) Lifestyle (good sleep, regular hydration and nutrition with safe water/food, regular fruits and vegetables, improve recovery strategies…), (9) Environmental considerations (heat, cold, air cleaning, changes or climatic conditions…), (10) Safety (equipment, rules, own-practice in athletics, and extra-sport activities). These ten tips “PREVATHLES” are based on our field experience in addition to existing epidemiological and experimental literature in athletics and other sports. Although there is currently no scientific evidence for their efficacy, sound judgement, and logical practice provide a strong basis, and given the low risk of using them in the benefit/risk balance, we suggest athletes and those around them follow these ten tips to limit the impact of injury/illness on championship performance.

Relation of Team Size and Success With Injuries and Illnesses During Eight International Outdoor Athletics Championships

Introduction: The number of injuries and illnesses during major athletics championships vary according to sex and discipline. They may also differ between countries (national teams) given the differences in training, medical care, nutrition, lifestyle habits, and in travel to the championships. In addition, injuries and illnesses may influence the performance during the championships. Therefore, the aim was to analyse the differences in the injury and illness occurrence during international outdoor athletics championships with regards to the athlete's country, as well as establishing the potential relationships with the success of the country during the respective championships. Method: The national medical teams and the local organizing committee physicians reported all injuries and illnesses daily on a standardized injury and illness report form during 4 World and 4 European outdoor championships from 2007 to 2018. Results were presented as number of registered athletes, injuries, illnesses and medals (absolute and per 1000 registered athletes), and for countries of different team size. Results: During these 8 championships, a total of 219 different countries participated with a total of 13059 registered athletes who incurred 1315 injuries and 550 illnesses. The number of injuries and illnesses per championships varied between countries. Countries with higher numbers of registered athletes had a higher number of injuries and illnesses, as well as a higher number of medals and gold medals. There were significant positive correlations between number of injuries/illnesses and number of registered athletes, medals, gold medals. Injury and illness numbers per 1,000 registered athletes differed between countries and team sizes. Analyzing country participation grouped according to the number of registered athletes, there were significant negative correlations between injury/illness and medals/gold medals per 1,000 registered athletes. Conclusions: Given the correlation between health problems and country size, we suggest that medical services provision and staff should be adapted to the team size. In groups of different country team sizes, lower number of injuries and illnesses per registered athletes were correlated with higher number of medals and gold medals per registered athletes, which can support that injury and illness prevention should be recognized as a win-win performance-prevention strategy.

Sports injury and illness incidence in the PyeongChang 2018 Olympic Winter Games: a prospective study of 2914 athletes from 92 countries

Objective

To describe the incidence of injuries and illnesses sustained during the XXIII Olympic Winter Games, hosted by PyeongChang on 9–25 February 2018.

Methods

We recorded the daily number of athlete injuries and illnesses (1) through the reporting of all National Olympic Committee (NOC) medical teams and (2) in the polyclinic and medical venues by the PyeongChang 2018 medical staff.

Results

In total, 2914 athletes (1210 women, 42%; 1704 men, 58%) from 92 NOCs were observed for occurrence of injury and illness. NOC and PyeongChang 2018 medical staff reported 376 injuries and 279 illnesses, equalling 12.6 injuries and 9.4 illnesses per 100 athletes over the 17-day period. Altogether, 12% of the athletes incurred at least one injury and 9% at least one illness. The injury incidence was highest in ski halfpipe (28%), snowboard cross (26%), ski cross (25%), snowboard slopestyle (21%) and aerials (20%), and lowest in Nordic combined, biathlon, snowboard slalom, moguls and cross-country skiing (2%–6%). Of the 376 injuries recorded, 33% and 13% were estimated to lead to ≥1 day and >7 days of absence from sport, respectively. The highest incidences of illness were recorded in biathlon (15%), curling (14%), bobsleigh (14%) and snowboard slalom (13%). Thirty per cent of the illnesses were expected to result in time loss, and 70% affected the respiratory system. Women suffered 61% more illnesses than men.

Conclusion

Overall, 12% of the athletes incurred at least one injury during the Games and 9% an illness, incidences that are similar to the Olympic Winter Games of 2010 and 2014.

Acute effect of taping on plantar pressure characteristics in athletes with exercise-induced leg pain: a description and comparison of groups

OBJECTIVES

Foot pronation is considered as a potential risk factor of lower leg overuse injury. This study aimed to identify plantar pressure characteristics of elite athletes with exercise-induced leg pain in throwing athletic disciplines, and to verify the acute effect of taping for restricting foot pronation by analyzing the plantar pressure characteristics.

METHODS

This study was designed as a description and comparison of throwing athletic athletes. Participants were divided into exercise-induced leg pain (ELP group, n = 17) and control groups (CON group, n = 14). Plantar pressure variables (contact area, maximum force, and peak pressure) at eight-foot regions in athletes' supporting leg were recorded during standing on one leg and a natural walk before and after applying anti-pronation or sham taping techniques.

RESULTS

There are significant difference of contact area, maximal force, and peak pressure in some regions of their foot between the ELP and CON groups. But the anti-pronation taping decreased only the peak pressure in lateral midfoot of CON group during a natural walk (p = 0.002).

CONCLUSION

The anti-pronation taping technique may not be effective preventive strategy from the exercise-induced leg pain, such as shin splints.

Health promotion by International Olympic Sport Federations: priorities and barriers

Objective

To identify changes in International Federations’ priorities and the barriers to implementing athlete and global health initiatives. Results should influence the work of the International Federation medical committees, the IOC and the Association of Summer Olympic International Federation.

Methods

The 28 Summer and 7 Winter International Federations participating in the most recent Olympic Games (2016; 2018) were surveyed to (i) identify the importance of 27 health topics, (ii) assess their progress on implementation health-related programmes and (iii) the barriers to implementation of these programmes. We compared International Federations’ activities in 2016 and 2017.

Results

The response rate was 83%. Health topics which most International Federations regarded as important and in which the International Federations felt insufficiently active were ‘team physician certification’, ‘prevention of harassment and abuse’, ‘eating disorders/disordered eating’, ‘mental health’ and ‘injury surveillance’. Compared with 2016, there was a decrease in International Federations’ activities in ‘injury surveillance’, ‘nutritional supplements’ and ‘hyperandrogenism’. The main barrier to implementing health-related programmes was ‘International Federation political support/willingness’, followed by ‘knowledge’. ‘Time’ and ‘coach support’ were more often reported than ‘finances’, or ‘IOC or Association of Summer Olympic International Federations partnership’.

Conclusion

If International Federations are going to promote health of athletes and global health promotion through physical activity (sport), International Federation leadership must change their focus and provide greater political support for related initiatives. Improving coach and athlete knowledge of the health issues could also facilitate health programme delivery. Time constraints could be mitigated by sharing experiences among the International Federations, Association of Summer Olympic International Federations and the IOC. International Federations should focus on those health-related topics that they identified as being important, yet rate as having insufficient activity.

Nutrition for the Prevention and Treatment of Injuries in Track and Field Athletes

Injuries are an inevitable consequence of athletic performance with most athletes sustaining one or more during their athletic careers. As many as one in 12 athletes incur an injury during international competitions, many of which result in time lost from training and competition. Injuries to skeletal muscle account for over 40% of all injuries, with the lower leg being the predominant site of injury. Other common injuries include fractures, especially stress fractures in athletes with low energy availability, and injuries to tendons and ligaments, especially those involved in high-impact sports, such as jumping. Given the high prevalence of injury, it is not surprising that there has been a great deal of interest in factors that may reduce the risk of injury, or decrease the recovery time if an injury should occur: One of the main variables explored is nutrition. This review investigates the evidence around various nutrition strategies, including macro- and micronutrients, as well as total energy intake, to reduce the risk of injury and improve recovery time, focusing upon injuries to skeletal muscle, bone, tendons, and ligaments.

Ultrasound-detected connective tissue involvement in acute muscle injuries in elite athletes and return to play: The French National Institute of Sports (INSEP) study

OBJECTIVES

Previous MRI studies showed that involvement of connective tissue in muscle injuries may prolong recovery times. The relevance of ultrasound assessment of connective tissue involvement as a prognostic factor is unknown. The aim was to test the hypothesis that ultrasound-detected connective tissue involvement in acute muscle injuries are related to longer recovery times.

DESIGN

Cohort study.

METHODS

Seventy consecutive elite athletes from the French National Institute of Sports (INSEP) sustaining an acute muscle injury showing positive findings on ultrasound at baseline were included. Ultrasound was systematically performed within 7days after the injury for the assessment of severity (grades 1-4) and type of injury in regard to the absence (M injuries) or presence (C injuries) of connective tissue involvement. The differences in the mean time needed to return to play (RTP) between the different grades and types of injury were assessed using multiple non-parametric tests.

RESULTS

When considering the overall grades independently of the type of injury (M or C), an increase in the mean time needed to RTP was observed with the increase of grades (p<0.0001). The same relationship was found when considering grades from M and C injuries separately, with higher grades of injuries exhibiting longer times needed to RTP (p<0.0001). Longer times needed to RTP were observed in athletes demonstrating C injuries in comparison to the ones exhibiting M injuries overall (p=0.002).

CONCLUSIONS

Ultrasound-detected connective tissue involvement in acute muscle injuries are related to longer times needed to RTP, especially when disruption is detected.

Acute and overuse injuries among sports club members and non-members: the Finnish Health Promoting Sports Club (FHPSC) study

Background

Physical activity in adolescence is promoted for its multi-dimensional health benefits. However, too intensive sports participation is associated with an increased injury risk. Our aim was to compare the occurrence of acute and overuse injuries in Finnish sports club members and non-members and to report training and competing habits associated with a higher injury risk in sports club members.

Methods

In this cross-sectional survey targeted at 14–16-year-old adolescents, a structured questionnaire was completed by 1077 sports club members and 812 non-members. The main outcome measures were self-reported acute and overuse injuries, their location and type.

Results

At least one acute injury in the past year was reported by 44.0% of sports club members and 19.8% of non-members (P < 0.001). The sex-adjusted odds ratio (OR) for acute injury in sports club members compared to non-members was 3.13 (95% confidence interval (95% CI) 2.54–3.87). Thirty-five percent of sports club members and 17.4% of non-members (P < 0.001) reported at least one overuse injury during the past year. The overuse injury OR for sports club members was 2.61 (95% CI 2.09–3.26). Sports club members who trained 7–14 h per week during training (OR 1.61, 95% CI 1.21–2.12, P = 0.001) or competition season (OR 1.55, 95% CI 1.18–2.06, P = 0.002) were more likely to report an injury compared to members who trained 3–6 h per week. Those sports club members who participated in forty competitions or more compared to 7–19 competitions per year were more likely to report an acute injury (OR 1.55, 95% CI 1.05–2.08, P = 0.028) or for an overuse injury (OR 1.53, 95% CI 1.02–2.30, P = 0.038).

Conclusions

Both acute and overuse injuries are common among youth sports club members, and the number increases along with increasing amounts of training and competitions. More effective injury prevention is needed both for adolescents engaging in sports club activities and for other adolescents.

Electronic supplementary material

The online version of this article (10.1186/s12891-019-2417-3) contains supplementary material, which is available to authorized users.

Muscle Injuries in Sports: A New Evidence-Informed and Expert Consensus-Based Classification with Clinical Application

Muscle injuries are among the most common injuries in sport and continue to be a major concern because of training and competition time loss, challenging decision making regarding treatment and return to sport, and a relatively high recurrence rate. An adequate classification of muscle injury is essential for a full understanding of the injury and to optimize its management and return-to-play process. The ongoing failure to establish a classification system with broad acceptance has resulted from factors such as limited clinical applicability, and the inclusion of subjective findings and ambiguous terminology. The purpose of this article was to describe a classification system for muscle injuries with easy clinical application, adequate grouping of injuries with similar functional impairment, and potential prognostic value. This evidence-informed and expert consensus-based classification system for muscle injuries is based on a four-letter initialism system: MLG-R, respectively referring to the mechanism of injury (M), location of injury (L), grading of severity (G), and number of muscle re-injuries (R). The goal of the classification is to enhance communication between healthcare and sports-related professionals and facilitate rehabilitation and return-to-play decision making.

Higher frequency of hamstring injuries in elite track and field athletes who had a previous injury to the ankle - a 17 years observational cohort study

Background

Inversion injury to the ankle and hamstring injuries are common problems in most sports. It is not known whether these injuries constitute a predisposing factor or a precursor of injury or re-injury of these anatomical locations. Therefore, we wished to test the hypothesis that a previous inversion ankle injury exerted a significant effect on the chance of an athlete suffering from a subsequent ipsilateral hamstring injury and vice versa.

Methods

In an observational cohort study over 17 years (1998–2015), 367 elite track and field athletes, were grouped according to their first traumatic isolated ankle or hamstring injury. Fifty athletes experienced both injuries. The Mann-Whitney U and Chi-square tests (p < 0.05) were performed to test possible associations of ankle and hamstring injury with age, gender, athletics discipline, grade, and type of antecedent injury.

Results

Athletes with a preceding ankle injury had a statistically significantly higher chance of experiencing a subsequent hamstring injury compared with athletes who had experienced a hamstring injury as their first traumatic event (x² = 4.245, p = 0.039). The proportion of both ankle and hamstring injury events was not statistically different between female (18%) and male (11%) athletes. Age and grade of injury did not influence the proportion of ankle and/or hamstring injury events.

Conclusion

There is a statistically significantly higher frequency of hamstring injuries in elite track and field athletes having experienced a previous ankle ligament injury.

Imaging-detected acute muscle injuries in athletes participating in the Rio de Janeiro 2016 Summer Olympic Games

BACKGROUND

Acute muscle injuries in elite athletes are responsible for a large portion of time loss injuries.

AIM

To describe the frequency, the anatomic distribution, and severity of imaging-detected acute muscle injuries among athletes who competed in the Rio de Janeiro 2016 Summer Olympics.

METHODS

We recorded all sports injuries reported by the National Olympic Committee medical teams and the Organising Committee medical staff during the 2016 Summer Olympics. Imaging of acute muscle injuries was performed at the IOC's polyclinic within the Olympic Village using ultrasound and 3.0 T and 1.5 T MRI scanners. The assessment of images was performed centrally by three musculoskeletal radiologists. The distribution of injuries by anatomic location and sports discipline and the severity of injuries were recorded.

RESULTS

In total, 11 274 athletes from 207 teams were included. A total of 1101 injuries were reported. Central review of radiological images revealed 81 acute muscle injuries in 77 athletes (66% male, mean age: 25.4 years, range 18-38 years). Athletics (track and field) athletes were the most commonly affected (n=39, 48%), followed by football players (n=9, 11%). The majority of injuries affected muscles from lower limbs (n=68, 84%), with the hamstring being the most commonly involved. Most injuries were grade 2 injuries according to the Peetrons classification (n=44, 54%), and we found 18 injuries exhibiting intramuscular tendon involvement on MRI.

CONCLUSION

Imaging-detected acute muscle injuries during the 2016 Summer Olympics affected mainly thigh muscles in athletics disciplines.

Health promotion through sport: international sport federations’ priorities, actions and opportunities

Objective

To identify areas of priority and activity for international sportsfederations (IFs) with respect to athlete health and safety, and global health. Results serve to direct the work of the Association of Summer Olympic IF Medical and Scientific Consultative Group, the International Olympic Committee and to influence IFs’ planning and priorities.

Methods

The 28 IFs participating in the Summer Olympic Games (2016) were asked to rank the relative importance of 11 health-related topics and to report their activities or research initiatives on 27 identified topics using an electronic survey. A comparison with a similar survey (2012) was made.

Results

The response rate was 100%. In general, the ‘fight against doping’ had the highest priority followed by ‘image as a safe sport’. The topics with the lowest importance ratings were ‘increasing the number of elite athletes’, and ‘health of the general population’. Despite ranking ‘health of your athletes,’ as a top priority, IFs are not addressing all aspects of athlete health. In comparison with 2012, there was a significant decrease in priority for IFs is ‘health of the general population’.

Conclusion

Despite the widespread knowledge of the importance of the promotion of physical activity (sport) on global health, the decreasing priority and programming of the IFs on physical activity promotion is concerning. Although IFs have prioritised the protection of the health of elite athletes, there are gaps in programming demonstrating that IFs are missing important areas of athlete health. Improving recreational athlete health programming could also benefit population health as well as improve IF fan base and sport participation.

Risk of Injuries in Paralympic Track and Field Differs by Impairment and Event Discipline: A Prospective Cohort Study at the London 2012 Paralympic Games

BACKGROUND

The incidence rates (IRs) and factors associated with injuries in the sport of Paralympic athletics (track and field) have not been comprehensively and prospectively studied.

PURPOSE

To determine injury IRs, characteristics of injuries, and associated factors in the sport of athletics at the London 2012 Paralympic Games.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A total of 977 athletes competing in the sport of athletics were followed over a total 10-day competition period of the Paralympic Games. Daily injury data were obtained via 2 databases: (1) a custom-built, web-based injury and illness surveillance system (WEB-IISS), maintained by team medical personnel; and (2) the organizing committee database, maintained by medical providers in the medical stations operated by the London Organising Committee of the Olympic and Paralympic Games. Athlete impairment and event discipline were obtained via the International Paralympic Committee athlete database. IRs (injuries per 1000 athlete-days) by impairment, event discipline, sex, and age were examined.

RESULTS

The overall IR was 22.1 injuries per 1000 athlete-days (95% CI, 19.5-24.7). In track disciplines, ambulant athletes with cerebral palsy experienced a lower incidence of injuries (IR, 10.2; 95% CI, 4.2-16.2) when compared with ambulant athletes from other impairment categories. Athletes in seated throwing experienced a higher incidence of injuries (IR, 23.7; 95% CI, 17.5-30.0) when compared with athletes in wheelchair racing (IR, 10.6; 95% CI, 5.5-15.6). In both track and field disciplines, the majority of injuries did not result in time loss from competition or training. Ambulant athletes experienced the greatest proportion of injuries to the thigh (16.4% of all injuries; IR, 4.0), observed predominantly in track athletes. Wheelchair or seated athletes experienced the greatest proportion of injuries to the shoulder/clavicle (19.3% of all injuries; IR, 3.4), observed predominantly in field athletes.

CONCLUSION

This is the first prospective cohort study examining injury IRs and associated factors in the sport of athletics at the Paralympic Games. Injury patterns were specific to the event discipline and athlete impairment. The majority of injuries occurred to the thigh (ambulant athletes) or shoulder/clavicle (wheelchair or seated athletes) and did not result in time loss.

Methodological quality of the injury surveillance system used in international athletics championships

OBJECTIVES

Incidence and prevalence data obtained from injury surveillance studies could be biased by the response rate as well as by the completeness and quality of the reports. It therefore appears crucial to analyse the quality of the injury surveillance system itself and thereby validate the quality of the data. This study aimed to analyse the quality of and compliance with the injury surveillance system implemented during international athletics championships.

DESIGN

Prospective, epidemiological study.

METHODS

The national medical teams and the local organising committee physicians daily reported all injuries on a standardised injury report form during 14 international athletics championships from 2007 to 2015. The quality of the injury surveillance system was analysed following the guidelines laid down by the Centre for Disease Control and Prevention.

RESULTS

On average 41.7±17.4% (mean±standard deviation) of all registered countries participated in the injury surveillance project, accounting for a coverage of athletes of 79.5±10.2% of all registered athletes. Their medical staff returned 89.2±8.4% of the expected injury report forms (information is missing for one championship). The completeness of injury data provided by medical teams and local organising committee physicians averaged 95.8±6.5%. National medical teams reported 60.6±16.6% of all injuries, and local organising committee physicians 28.7±15.0% whereas 10.6±6.5% of injuries were reported by both.

CONCLUSIONS

The injury surveillance system used during international athletics championships provided good national medical team participation, coverage of athletes, response rate, and completeness of reports. These parameters should be systematically reported for injury surveillance studies to show the quality of the study.

Football injuries during the 2014 FIFA World Cup

Background

FIFA has surveyed match injuries in its tournaments since 1998.

Aim

To analyse the incidence and characteristics of match injuries incurred during the 2014 FIFA World Cup in comparison to previous FIFA World Cups.

Methods

The chief physicians of the participating teams reported all newly incurred injuries of their players after the match on a standardised report form. 124 (97%) forms were returned.

Results

A total of 104 injuries were reported, equivalent to an incidence of 1.68 injuries per match (95% CI 1.36 to 2.00). 64 (63.4%) injuries were caused by contact with another player. Thigh (26; 25%) and head (19; 18%) were the most frequently injured body parts. The most frequent diagnosis was thigh strain (n=18). Five concussions and three fractures to the head were reported. While most thigh strains (15/17; 88.2%) occurred without contact, almost all head injuries (18/19; 94.7%) were caused by contact. 0.97 injuries per match (95% CI 0.72 to 1.22) were expected to result in absence from training or match. Eight injuries were classified as severe. The incidence of match injuries in the 2014 FIFA World Cup was significantly lower than the average of the four preceding FIFA World Cups, both for all injuries (2.34; 95% CI 2.15 to 2.53) and time-loss injuries (1.51; 95% CI 1.37 to 1.65).

Conclusions

The overall incidence of injury during the FIFA World Cups decreased from 2002 to 2014 by 37%. A detailed analysis of the injury mechanism is recommended to further improve prevention strategies.

Sprint Acceleration Mechanics: The Major Role of Hamstrings in Horizontal Force Production

Recent literature supports the importance of horizontal ground reaction force (GRF) production for sprint acceleration performance. Modeling and clinical studies have shown that the hip extensors are very likely contributors to sprint acceleration performance. We experimentally tested the role of the hip extensors in horizontal GRF production during short, maximal, treadmill sprint accelerations. Torque capabilities of the knee and hip extensors and flexors were assessed using an isokinetic dynamometer in 14 males familiar with sprint running. Then, during 6-s sprints on an instrumented motorized treadmill, horizontal and vertical GRF were synchronized with electromyographic (EMG) activity of the vastus lateralis, rectus femoris, biceps femoris, and gluteus maximus averaged over the first half of support, entire support, entire swing and end-of-swing phases. No significant correlations were found between isokinetic or EMG variables and horizontal GRF. Multiple linear regression analysis showed a significant relationship (P = 0.024) between horizontal GRF and the combination of biceps femoris EMG activity during the end of the swing and the knee flexors eccentric peak torque. In conclusion, subjects who produced the greatest amount of horizontal force were both able to highly activate their hamstring muscles just before ground contact and present high eccentric hamstring peak torque capability.

Sports injuries and illnesses in the Sochi 2014 Olympic Winter Games

BACKGROUND

Systematic surveillance of injuries and illnesses is the foundation for developing preventive measures in sport.

AIM

To analyse the injuries and illnesses that occurred during the XXII Olympic Winter Games, held in Sochi in 2014.

METHODS

We recorded the daily occurrence (or non-occurrence) of injuries and illnesses (1) through the reporting of all National Olympic Committee (NOC) medical teams and (2) in the polyclinic and medical venues by the Sochi 2014 medical staff.

RESULTS

NOC and Sochi 2014 medical staff reported 391 injuries and 249 illnesses among 2780 athletes from 88 NOCs, equalling incidences of 14 injuries and 8.9 illnesses per 100 athletes over an 18-day period of time. Altogether, 12% and 8% of the athletes incurred at least one injury or illness, respectively. The percentage of athletes injured was highest in aerial skiing, snowboard slopestyle, snowboard cross, slopestyle skiing, halfpipe skiing, moguls skiing, alpine skiing, and snowboard halfpipe. Thirty-nine per cent of the injuries were expected to prevent the athlete from participating in competition or training. Women suffered 50% more illnesses than men. The rate of illness was highest in skeleton, short track, curling, cross-country skiing, figure skating, bobsleigh and aerial skiing. A total of 159 illnesses (64%) affected the respiratory system, and the most common cause of illness was infection (n=145, 58%).

CONCLUSIONS

Overall, 12% of the athletes incurred at least one injury during the games, and 8% an illness, which is similar to prior Olympic Games. The incidence of injuries and illnesses varied substantially between sports.