Research Articles (Sport, Exercise Medicine & Lifestyle Institute (SEMLI))
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Item Injury and illness epidemiology in elite athletes during the Olympic, Youth Olympic and Paralympic Games : a systematic review and meta-analysis(BMJ Publishing Group, 2025-09) Torvaldsson, Kalle; Fagher, Kristina; Derman, Wayne; Engebretsen, Lars; Lindblom, Hanna; Lopes, Alexandre Dias; Runciman, Phoebe; Schwellnus, Martin Peter; Soligard, Torbjorn; Sonesson, Sofi; Steffen, Kathrin; Hagglund, MartinOBJECTIVE : To systematically review and synthesise the incidence and characteristics of injuries and illnesses among athletes participating in the Olympic, Youth Olympic and Paralympic Games. DESIGN : Systematic review and meta-analysis. DATA SOURCES : PubMed, Embase, CINAHL, Scopus and Web of Science were searched up to 2 July 2024, and Google Scholar, ClinicalTrials.gov and WHO International Clinical Trials Registry Platform up to 12 December 2023. ELIGIBILITY CRITERIA FOR SELECTING STUDIES : Cohort studies conducted during the Games reporting injuries and illnesses among athletes. Risk of bias was assessed using the Joanna Briggs Institute critical appraisal tool for prevalence studies, and certainty of evidence using the Grading of Recommendations, Assessment, Development and Evaluation framework. RESULTS : 27 articles were included (10 Olympic, 4 Youth Olympic and 13 Paralympic Games). 23 articles had low, 3 moderate and 1 high risk of bias. Certainty of evidence was high to moderate for Olympic, high to low for Youth Olympic and low for Paralympic Games. Injury incidences per 1000 athlete-days were 6.5 (95% CI 5.9 to 7.2) during Olympic, 10.5 (95% CI 9.4 to 11.8) during Youth Olympic and 14.3 (95% CI 9.9 to 20.7) during Paralympic Games. Illness incidences per 1000 athlete-days were 3.6 (95% CI 2.8 to 4.7), 6.9 (95% CI 6.1 to 7.8) and 9.7 (95% CI 6.5 to 14.4), respectively. Lower limb injuries were frequent during Olympic and Youth Olympic Games, upper limb injuries during Paralympic Games and respiratory illnesses across all Games cohorts. CONCLUSIONS : Injury and illness incidences were highest in Paralympic Games, followed by Youth Olympic and Olympic Games. Incidences and patterns of injury and illness were sport and context specific, which could inform future prevention strategies.Item Sex, training variables, history of chronic disease, and chronic injury are risk factors associated with a history of exercise-associated muscle cramping in 10,973 ultramarathon race entrants : a safer XXXVIII study(Edizioni Minerva Medica S.p.A., 2024-09) MacMillan, Candice; Sewry, Nicola Ann; Schwellnus, Martin Peter; Boulter, Jeremy; Dyer, Marlise; Jordaan, Esme; candice.macmillan@up.ac.zaBACKGROUND : The prevalence of a history of exercise-associated muscle cramping (hEAMC) among ultramarathon runners is high. While the Comrades is one of the most popular mass community-based participation ultramarathons (90 km) globally, research on the epidemiology, clinical characteristics, and risk factors of entrants' lifetime hEAMC are scarce. This research aimed to describe the epidemiology, clinical characteristics, and risk factors of hEAMC among Comrades Marathon entrants. METHODS : This was a retrospective, cross-sectional study in which 10973 race entrants of the 2022 Comrades Marathon participated. Entrants completed a prerace medical screening questionnaire that included questions related to the lifetime prevalence (%; 95% CI), severity, treatment and risk factors (demographics, training/racing variables, chronic disease/allergies, injury) for EAMC. RESULTS : One thousand five hundred eighty-two entrants reported hEAMC in their lifetime (14.4%; 95% CI: 13.77-15.09). There was a significantly (P<0.01) higher prevalence of male (16.10%; 95% CI:15.34-16.90) than female (8.31%; 95% CI: 7.27-9.50) entrants with hEAMC (PR=1.94; 95% CI:1.68-2.23). The prevalence of hEAMC was highest in entrants with a: 1) 1 disease increase in composite disease score (PR=1.31; 95% CI:1.25-1.39); 2) history of collapse (PR=1.87; 95% CI 1.47-2.38); 3) past chronic musculoskeletal (MSK) injury (PR=1.71; 95% CI 1.50-1.94); and 4) MSK injury in the previous 12 months (PR=2.38;95% CI: 2.05-2.77). Training-related risk factors included an increase of 10 km weekly running distance (PR=0.97; 95% CI:0.95-0.99) and a training pace increase of 1min/ km (slower) (PR=1.07; 95% CI:1.03-1.12). CONCLUSIONS : Future research should investigate the causal relationship between risk factors identified and hEAMC in ultramarathon runners. Findings from this study could assist in effective anticipation and adequate planning for treating EAMC encounters during community-based mass participation events.Item Protecting respiratory health of athletes : an Olympic challenge(Elsevier, 2024-07) Hull, James H.; Clemm, Hege; Backer, Vibeke; Koehle, Michael; Mountjoy, Margo; Schwellnus, Martin Peter; Olin, J. TodThe summer of 2024 will be remembered in part for the XXXIII Olympic and Paralympic Games in Paris, France. The Games provide a platform to highlight the value of sporting participation and remind us of the widespread health benefits of regular exercise, including for cardiovascular, metabolic, mental, and respiratory healthItem The cardiovascular response to exercise in athletes recovering from SARS-CoV-2 infection : a prospective cohort study with repeated measures over 16 weeks - AWARE IX(Routledge, 2023) Kaulback, Kelly; Schwellnus, Martin Peter; Sewry, Nicola Ann; Lombard, Carl; Jordaan, Esme; Wood, Paola SilviaHigher exercise heart rate (HR) and prolonged return-to-sport in athletes with SARS-CoV-2 infection are described, but the cardiovascular response to exercise during recovery is not understood. This prospective, cohort, experimental study with repeated measures evaluated the cardiovascular response to exercise over 16 weeks in athletes recovering from SARS-CoV-2 infection. Athletes (n = 82) completed 2–5 repeat assessments at regulated intervals over 16 weeks post-SARS-CoV-2 infection. Data from 287 assessments (submaximal exercise tests; Modified Bruce protocol) are included. HR (bpm), systolic blood pressure (SBP) (mmHg) and rating of perceived exertion (RPE) (Borg scale 6–20) were measured. Rates of change in HR, SBP and RPE over time are reported. Submaximal exercise HR, SBP and RPE decreased significantly over 16 weeks (p < 0.01). There was a steeper rate of decline for HR and RPE ≤30 days compared to >30 days after SARS-CoV-2 infection: HR at Stage 3: ≤30 days −0.53 (0.01); >30 days −0.06 (0.02) and Stage 5: ≤30 days −0.77 (0.12); >30 days −0.12 (0.02); RPE at Stage 3: ≤30 days −0.09 (0.02); >30 days −0.01 (0.0002) and Stage 5: ≤30 days −0.13 (0.02); >30 days −0.02 (0.004). The findings provide clinical recommendation for exercise prescription and monitoring RPE in response to exercise post-SARS-CoV-2 infection and contribute to the clinical understanding of recovery which can help manage athlete expectations.Item Pre-race medical clearance in 60,609 distance running race entrants : which entrants sought clearance, what physicians did, and what was the outcome? SAFER XXXVII(Edizioni Minerva Medica, 2025-04) Muller, Christili; Schwellnus, Martin Peter; Janse van Rensburg, Dina Christina; Jordaan, Esme; Sewry, Nicola Ann; nicola.sewry@up.ac.zaBACKGROUND : Medical clearance is often recommended for athletes prior to endurance exercise. The primary aim was to determine the percentage (%) of race entrants that sought medical clearance prior to participation in endurance running events, describe the diagnostic modalities used by doctors to assess entrants seeking medical clearance, and the clearance advice given. Secondary aims were to investigate the factors associated with seeking and outcome of clearance. METHODS : All consenting race entrants who completed an online screening questionnaire during registration to participate in the 21.1 km or 56 km Two Oceans marathon races from 2013-2015 (N.=60,609) were included. Runners were stratified into four risk categories: low risk (LR), intermediate risk (IR), high risk (HR) and very high risk (VHR). Runners were asked if they consulted with a medical doctor to obtain medical clearance. Follow-up questions enquired about what the doctor did when they sought medical clearance and what advice the doctor gave as an outcome of the medical clearance consultation. Prevalence (%, 95% CI) and Prevalence Ratios (PRs) are reported. RESULTS : Over the 3-year period, 14.8% of entrants sought medical clearance. For clearance, doctors used history only (9.9%), history and physical examination (36.7%) and history, physical examination, and special investigations (53.0%). Most entrants seeking medical clearance were fully cleared to race (87.7% in 21.1 km and 85.9% in 56 km) (P=0.0156). Factors associated with seeking medical clearance include longer race distance, older age and a higher risk category (P<0.0001). CONCLUSIONS : The methods doctors use when conducting medical clearance consultations vary greatly. Further research is suggested to develop a protocol that doctors can use for medical consultations.Item Years of running, chronic diseases, and allergies are associated with gradual onset Achilles tendon injuries in 61,252 running race entrants(Wiley, 2024-11) Young, Jonah Dylan; Wood, Paola Silvia; Schwellnus, Martin Peter; Jordaan, Esme; Swanevelder, SonjaBACKGROUND : Gradual-onset Achilles tendon injuries (GoATIs) in runners are common. Data show that chronic diseases are associated with GoATI. OBJECTIVE : To determine risk factors associated with a history of GoATIs among long-distance runners (21.1 and 56 km) entering a mass community-based running event. METHODS : Online pre-race medical screening questionnaire data from 76,654 consenting Two Ocean Marathon race entrants (71.8% entrants) were collected prospectively over 4 years (2012-2015); this cross-sectional study is a retrospective analysis of these data. A total of 617 entrants (0.8%) reported a GoATI in the last 12 months; 60,635 entrants reported no history of any running injury (controls). Categories of factors associated with GoATI were explored (univariate and multiple regression analyses): demographics (age group, sex, race, distance), training/racing history, and history of allergy, history of chronic disease, and Composite Chronic Disease Score. Prevalence and prevalence ratios (PRs; 95% CI) are reported. RESULTS : Factors associated with a higher prevalence of a history of GoATI (univariate analysis vs. controls) were older age (>31 years) (p < .001), male sex (PR = 1.76; p < .001), and longer race distance (56 km vs. 21.1 km) (PR = 2.06; p < .001). Independent factors associated with a history of GoATI (multiple regression) were increased years of recreational running (PR = 1.17 for every 5-year increase, p < .001), higher Composite Chronic Disease Score (PR = 2.07 for every 2-unit increase, p < .001), and allergy history (PR = 1.98 p < .001). CONCLUSION : Novel independent factors associated with a history of GoATI in distance runners were increased years of recreational running, chronic disease history, and allergy history. Runners at risk for GoATI could be targeted for injury prevention interventions. Future studies should focus on establishing a causal relationship.Item Point-of-care testing to detect respiratory infections in athletes : what is the role?(BMJ Publishing Group, 2024-09) Hull, James H.; Schwellnus, Martin Peter; Valtonen, MaaritAcute respiratory illness (ARI) is the most common reason athletes seek acute medical care and represents a significant challenge to the sport and exercise medicine (SEM) clinician working ‘in the field’. Faced with this issue, there is a need to determine if symptoms are caused by an acute respiratory infection (ARInf), establish if a specific antimicrobial treatment is indicated, evaluate the risk of transmission and provide appropriate advice regarding the safety of ongoing sports participation.Item Number of symptoms during the acute phase of SARS-CoV-2 infection in athletes is associated with multiorgan involvement : AWARE III(Lippincott Williams and Wilkins, 2025) Snyders, Carolette; Dyer, Marlise; Jordaan, Esme; Scholtz, Leonie; Du Plessis, Andre; Mpe, Martin; Kaulback, Kelly; Schwellnus, Martin Peter; carolette.cloete@semli.co.zaOBJECTIVE : Acute respiratory infections (ARinf), including SARS-CoV-2 infection, can affect multiple organ systems that may influence return to sport (RTS) in athletes. Factors associated with multiorgan involvement in athletes with ARinf are lacking. The aim of this study was to explore whether factors such as demographics, sport participation, history of comorbidities/allergies, and number of acute symptoms are associated with multiorgan involvement in athletes with recent SARS-CoV-2 infection. DESIGN : Prospective cohort study with cross-sectional analysis. SETTING : Institutional clinical research facilities. PARTICIPANTS : Ninety-five athletes (18–60 years) underwent a comprehensive medical assessment 10 to 28 days after SARS-CoV-2 infection. INDEPENDANT FACTORS : Demographics, sport participation, history of comorbidities/allergies, and the number of acute symptoms (in 3 subgroups:1 = ≤5, 2 = 6-9, or 3 ≥ 10). MAIN OUTCOME MEASURES : Number of organs involved in athletes with recent SARS-CoV-2 infection. RESULTS : The number of organ systems involved was not associated with demographics (age, sex), sport participation (level and type), or history of comorbidities and allergies. However, the number of organ systems involved was significantly higher in athletes with 6 to 9 symptoms (subgroup 2) compared with those with ≤5 symptoms (subgroup 1) and this was more pronounced when comparing athletes with ≥10 symptoms (subgroup 3) with those with ≤5 symptoms (subgroup 1) (P < 0.0001). CONCLUSIONS : Total number of acute symptoms of SARS-CoV-2 infection is related to number of organ systems involved, which is a measure of disease severity, and could therefore influence RTS decision making. Future studies should explore whether this observation holds for athletes with ARinf caused by other pathogens.Item Rating of perceived exertion associated with acute symptoms in athletes with recent SARS-CoV-2 infection : athletes with acute respiratory infection (AWARE) VI study(National Athletic Trainers' Association, 2024-01) Kaulback, Kelly; Schwellnus, Martin Peter; Sewry, Nicola Ann; Jordaan, Esme; Wood, Paola SilviaCONTEXT : SARS-CoV-2 infection can affect the exercise response in athletes. Factors associated with the exercise response have not been reported. OBJECTIVE : To (1) describe heart rate (HR), systolic blood pressure (SBP), and rating of perceived exertion (RPE) responses to exercise in athletes with a recent SARS-CoV-2 infection and (2) identify factors affecting exercise Responses. DESIGN : Cross-sectional, experimental study. PATIENTS OR OTHER PARTCIPANTS : Male and female athletes (age ¼ 24.2 6 6.3 years) with a recent (,28 days) SARS-CoV-2 infection (n ¼ 72). SETTING : A COVID-19 Recovery Clinic for athletes. MAIN OUTCOME MEASURE(S) : Heart rate, SBP, and RPE were measured during submaximal exercise (modified Bruce protocol) at 10 to 28 days after SARS-CoV-2 symptom onset. Selected factors (demographics, sport, comorbidities, pre-infection training variables, and symptoms during the acute phase of the infection) affecting the exercise response were analyzed using random coefficient (linear mixed) models. RESULTS : Heart rate, SBP, and RPE increased progressively from rest to stage 5 of the exercise test (P ¼ .0001). At stage 5 (10.1 metabolic equivalents), a higher HR and a higher SBP during exercise were associated with younger age (P ¼ .0007) and increased body mass index (BMI; P ¼ .009), respectively. Higher RPE during exercise was significantly associated with a greater number of whole-body (P ¼ .006) and total number (P ¼ .004) of symptoms during the acute phase of infection. CONCLUSIONS : A greater number of symptoms during the acute infection was associated with a higher RPE during exercise in athletes at 10 to 28 days after SARS-CoV-2 infection. We recommend measuring RPE during the first exercise challenge after infection, as this may indicate disease severity and be valuable for tracking progress, recovery, and return to sport.Item Air quality, respiratory health and performance in athletes : a summary of the IOC consensus subgroup narrative review on ‘Acute Respiratory Illness in Athletes’(BMJ Publishing Group, 2025-03) Bougault, Valerie; Carlsten, Christopher; Adami, Paolo Emilio; Sewry, Nicola Ann; Schobersberger, Wolfgang; Soligard, Torbjorn; Engebretsen, Lars; Budgett, Richard; Schwellnus, Martin Peter; Fitch, KenWith the WHO stating that nearly 99% of the global population is exposed to air pollution levels that increase the risk of chronic diseases, the question of exercising in polluted environments is relevant to the health of athletes. Major sporting events held under conditions of poor air quality (AQ) have highlighted the lack of answers to concerns raised by organisers and athletes about the associated health risks. This evidence-based narrative review compiles current knowledge and identifies gaps regarding the relationship between AQ and sport. It is a summary of a more comprehensive report prepared for the International Olympic Committee (IOC) Medical and Scientific Commission. This article discusses the various sources of air pollutants encountered during exercise, summarises current AQ guidelines and provides insights into AQ conditions during the Paris 2024 Olympic and Paralympic Games (OPG) as well as in Los Angeles over the past four summers, in preparation for the 2028 OPG. It also summarises the effects of air pollution on the respiratory health and performance of athletes, while proposing mitigation strategies, with a particular emphasis on AQ education.Item A high incidence of serious life-threatening cardiovascular medical encounters during a marathon (2014-2019) calls for prevention strategies : SAFER XL(Taylor and Francis, 2025) Green, Darren; Sewry, Nicola Ann; Derman, Wayne; Killops, Jannelene; Boer, Pieter Henk; Jordaan, Esme; Schwellnus, Martin PeterOBJECTIVES : The aim of this study was to determine the incidence and nature (severity and type by organ system and specific diagnosis) of all medical encounters (MEs), including serious/life-threatening MEs (SLMEs) during a South African road marathon. METHODS : This descriptive study was a retrospective analysis of data collected over 6 years at the Cape Town Marathon from 2014 to 2019, which included 40 446 starters. All MEs were collected and described as per the consensus statement for mass community-based sporting events. Incidences (I; per 1000 starters; 95% CI) are described for all MEs, SLMEs, and by organ system and specific diagnosis. RESULTS : The incidence of all MEs was 8.7 (95% CI: 7.8–9.6) per 1000 starters. The largest contributor to all MEs, by organ system affected, was cardiovascular-related, with an incidence of 1.8 (95% CI: 1.4–2.2), where exercise-associated postural hypotension was the most common specific diagnosis (I = 1.3; 95% CI: 1.0–1.7). The incidence of all SLMEs was 1.0 (95% CI: 0.7–1.4) making up 11.7% (41/350) of all MEs. The incidence of SLMEs by organ system was highest in the cardiovascular system (I = 0.4; 95% CI: 0.3–0.7), with acute coronary syndrome (ACS) (I = 0.2; 95% CI: 0.1–0.4) the most common specific diagnosis. There were no sudden cardiac deaths (SCD) nor sudden cardiac arrests (SCA). CONCLUSION : There was a high proportion of cardiovascular-related medical encounters, as well as SLMEs. We recommend that event organizers and race medical directors investigate prevention strategies to mitigate against risk of SLMEs, specifically acute cardiovascular SLMEs.Item Risk factors associated with a history of iliotibial band syndrome (hITBS) in distance runners : a cross-sectional study in 76 654 race entrants - a SAFER XXXIII study(Taylor and Francis, 2024) Marais, Jandre V.; Jansen van Rensburg, Audrey; Schwellnus, Martin Peter; Jordaan, Esme; Boer, Pieter HenkBACKGROUND : Despite the numerous health benefits of distance running, it is also associated with the development of ‘gradual onset running-related injuries’ (GORRIs) one of which is Iliotibial Band Syndrome (ITBS). Novel risk factors associated with a history of ITBS (hITBS) have not been described in a large cohort of distance runners. OBJECTIVE : To identify risk factors associated with hITBS in distance runners. DESIGN : Descriptive cross-sectional study. SETTING : 21.1 km and 56 km Two Oceans Marathon races (2012–2015). PARTICIPANTS : 106 743 race entrants completed the online pre-race medical screening questionnaire. A total of 1 314 runners confirmed an accurate hITBS diagnosis. METHODS : Selected risk factors associated with hITBS explored included: demographics (race distance, sex, age groups), training/running variables, history of existing chronic diseases (including a composite chronic disease score) and history of any allergy. Prevalence (%) and prevalence ratios (PR; 95% CI) are reported (uni- & multiple regression analyzes). RESULTS : 1.63% entrants reported hITBS in a 12-month period. There was a higher (p < 0.0001) prevalence of hITBS in the longer race distance entrants (56 km), females, younger entrants, fewer years of recreational running (PR = 1.07; p = 0.0009) and faster average running speed (PR = 1.02; p = 0.0066). When adjusted for race distance, sex, age groups, a higher chronic disease composite score (PR = 2.38 times increased risk for every two additional chronic diseases; p < 0.0001) and a history of allergies (PR = 1.9; p < 0.0001) were independent risk factors associated with hITBS. CONCLUSION : Apart from female sex, younger age, fewer years of running and slower running speed, two novel independent risk factors associated with hITBS in distance runners are an increased number of chronic diseases and a history of allergies. Identifying athletes at higher risk for ITBS can guide healthcare professionals in their prevention and rehabilitation efforts.Item Ready, set, go : medical preparations for the Paris 2024 Paralympic Games(Elsevier, 2024-11) Snyders, Carolette; Derman, Wayne; Schwellnus, Martin PeterIn August 2024, over 4400 Paralympic athletes will gather in Paris for the Paralympic Summer Games—the pinnacle of every Paralympian's (Para athletes competing at the Paralympic Games) career to showcase their ability and skills. Their training, preparation, and effort in the years leading up to the Games are unparalleled. To achieve success, Paralympians specifically rely on a medical support team to achieve their goals. So, what is required of the medical support team to prepare Paralympians to get ready, set, and go to Paris 2024?Item Increased number of symptoms during the acute phase of SARS-CoV-2 infection in athletes is associated with prolonged time to return to full sports performance—AWARE VIII(Elsevier, 2024-05) Snyders, Carolette; Dyer, Marlise; Sewry, Nicola Ann; Jordaan, Esme; Schwellnus, Martin PeterPURPOSE : The aim of the study was to identify factors associated with prolonged time to return to full performance (RTFP) in athletes with recent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS : Prospective cohort study with cross sectional analysis. A total of 84 athletes with confirmed SARS-CoV-2 infection assessed at a coronavirus disease 2019 recovery clinic gave a history of age, sex, type/level of sport, co-morbidities, pre-infection training hours, and 26 acute SARS-CoV-2 symptoms from 3 categories ("nose and throat", "chest and neck", and "whole body"/systemic). Data on days to RTFP were obtained by structured interviews. Factors associated with RTFP were demographics, sport participation, history of co-morbidities, pre-infection training history, and acute symptoms (type, number). Outcomes were: (a) days to RTFP (median, interquartile range (IQR)) in asymptomatic (n = 7) and symptomatic athletes (n = 77), and (b) hazard ratios (HRs; 95% confidence interval) for symptomatic athletes with vs. without a factor (univariate, multiple models). HR < 1 was predictive of higher percentage chance of prolonged RTFP. Significance was p < 0.05. RESULTS : Days to RTFP were 30 days (IQR: 23-40) for asymptomatic and 64 days (IQR: 42-91) for symptomatic participants (p > 0.05). Factors associated with prolonged RTFP (univariate models) were: females (HR = 0.57; p = 0.014), endurance athletes (HR = 0.41; p < 0.0001), co-morbidity number (HR = 0.75; p = 0.001), and respiratory disease history (HR = 0.54; p = 0.026). In symptomatic athletes, prolonged RTFP (multiple models) was significantly associated with increased "chest and neck" (HR = 0.85; p = 0.017) and "nose and throat" (HR = 0.84; p = 0.013) symptoms, but the association was more profound between prolonged RFTP and increased total number of "all symptoms" (HR = 0.91; p = 0.001) and "whole body"/systemic (HR = 0.82; p = 0.007) symptoms. CONCLUSION : A larger number of total symptoms and specifically "whole body"/systemic symptoms during the acute phase of SARS-CoV-2 infection in athletes is associated with prolonged RTFP.Item Countermeasures to reduce the risk of infections at the 2024 Olympic and Paralympic Games-a balancing act(Elsevier, 2024-11) Jooste, Marcel; Schwellnus, Martin PeterThe Olympic and Paralympic Games are a global celebration of athletic dedication and achievement, bringing together athletes and spectators from around the world. However, such large gatherings present public health challenges for the Organizing Committees and local governments. As highlighted by the coronavirus disease 2019 (COVID-19) pandemic, these events are associated with an increased risk of transmission of infections, which can significantly impact the health and well-being of athletes and attendees. Prioritizing the health and safety of athletes, officials and spectators is fundamental to ensure the successful hosting of the Games. Therefore, it is essential to design and implement comprehensive countermeasures to mitigate the risk of an infectious disease outbreak among participants but also to the residents of the host city.Item Risk factors associated with medical encounters in ultramarathon race starters – data from 103,131 race starters over 90 km : SAFER XLI(Elsevier, 2024-11) Sewry, Nicola Ann; Boulter, Jeremy; Seocharan, Ishen; Dyer, Marlise; Jordaan, Esme; Schwellnus, Martin PeterOBJECTIVES : To identify the risk factors associated with all medical encounters (MEs) and serious/life-threatening MEs (SLMEs) during the Comrades Marathon. DESIGN : Prospective cohort study, with cross-sectional analyses. METHODS : During the 2014–2019 Comrades Marathon, all MEs (including SLMEs) were recorded in 103,131 starters. For both all MEs and SLMEs, the following risk factors were explored: sex, age, route (“up” vs. “down” race), previous Comrades experience (yes/no), wet-blub globe temperature (WBGT) and race pace. Incidence (per 1000 starters; 95%CI), and the incidence ratio (IR; 95%CI) are presented. RESULTS : For all MEs, being female was a significant risk factor (females vs. males IR = 1.47, p < 0.0001), and age was only marginally significant (p = 0.0167). Therefore factors for all MEs were adjusted for sex. Other factors significantly associated with all MEs were: higher WBGT (highest WBGT compared to lowest, IR = 1.33, p = 0.0003), race pace (highest risk for those who finish either among the first quarter [IR = 1.49] or last quarter [IR = 1.46] compared to middle pace; p < 0.0001) and the route (“down” vs. “up”: IR = 1.11; p = 0.0181). Factors associated with higher risk for SLMEs were: females (IR = 1.9; p = 0.0003), “down” vs. “up” route (IR = 1.37; p = 0.0306) and race pace (slower and faster runners vs. mid (6.4–7.1 min/km) race pace category (IR > 2.1, p < 0.0001)). CONCLUSIONS : Intrinsic (female, faster and slower race pace) and extrinsic (higher WBGT and the “down” route) are novel risk factors associated with all MEs at this event. These can be considered by the race organizers and the medical team to develop and implement prevention strategies.Item Factors associated with a history of acute traumatic cycling injuries in 60 941 cycling race entrants in South Africa : SAFER study XLII(BMJ Publishing Group, 2024-10) Jansen van Rensburg, Bertus; Schwellnus, Martin Peter; Green, Darren; Jansen van Rensburg, Audrey; Jordaan, Esme; Swanevelder, Sonja; Sewry, Nicola AnnBACKGROUND : Information on acute traumatic cycling injuries (ATCIs) in the 12 months prior to entry in a cycling race and the predisposing factors have not been well-researched. OBJECTIVE : Determine factors associated with a history of ATCIs sustained in the previous 12 months by race entrants of a 109 km cycling race. METHODS : Descriptive, cross-sectional study on 60 941 Cape Town Cycle Tour race entrants from 2016 to 2020. Data on a history of ATCIs sustained in the previous 12 months were obtained through an online pre-race medical screening questionnaire (mandatory in 2016, and voluntary in 2017–2020). Factors investigated were demographics, cycling/training history and history of chronic disease, collapse, cramping, allergies and regular chronic prescription medication usage. We calculated the prevalence ratio (PR) for reporting a history of an ATCI in the previous 12 months for each category (multiple regression model). RESULTS : Factors associated with an increased PR for a history of ATCIs gathered from race entrants (34% of the total entrants) were: increased years of participation in distance cycling events >2 hours (PR=1.05 per 5 years of distance cycling, p<0.0001), increased weekly average training/racing distance of a cyclist in the past 12 months (PR=1.11 per 50 km increase in weekly cycling). Other factors were: increased number of chronic diseases reported (PR=1.53, per two additional chronic diseases reported, p<0.0001), history of collapse (PR=1.75, p=0.0005), history of cramping (PR=1.65, p<0.0001) and history of allergies (PR=1.49, p<0.0001). CONCLUSIONS : Subgroups of recreational cyclists at higher risk for ATCIs were identified. This information could assist in developing and implementing future strategies to mitigate ATCIs.Item Healthy environments for athleTes (HEAT) : environmental conditions along a 90 km ultra-marathon event, South Africa(Springer, 2024-09) Havenga, Henno; Gharbi, D.; Sewry, Nicola Ann; Language, B.; Neumann, F.H.; Finch, J.M.; Hill, T.; Boulter, Jeremy; Jordaan, Esme; Piketh, S.J.; Schwellnus, Martin Peter; Burger, R.P.This paper provides an overview of the HEAT (Healthy Environments for AthleTes) project, which aims to understand the impact of environmental conditions on athlete health and performance during major sporting events such as long-distance running, cycling, and triathlons. In collaboration with the SAFER (Strategies to reduce Adverse medical events For the ExerciseR) initiative, the HEAT project carried out a field campaign at the 2022 Comrades Marathon in the KwaZulu-Natal province of South Africa. The measurement campaign deployed seven weather stations, seven PM2.5 monitors and one spore trap along the 90 km route to capture spatially representative measurements of complex micro-climates, allergenic aerospora, and particulate matter exposure. The results indicate that runners were exposed to moderate risk heat stress conditions. Novel findings from this initial campaign shows elevated and potentially harmful PM2.5 levels at spectator areas, possibly coinciding with small fire events around the race day festivities. Our findings show values PM2.5 levels over the WHO 24-h guidelines at all stations, while 2000 µg/m3 at two stations. However, the lack of an acute exposure standard means direct health impacts cannot be quantified in the context of a sport event. The HEAT project highlights important aspects of race day monitoring; regional scale climatology has an impact on the race day conditions, the microclimatic conditions (pollution and meteorology) are not necessarily captured by proximity instruments and direct environmental measurements are required to accurately capture conditions along the route.Item Infographic. International Olympic Committee (IOC) consensus statement and clinical decision-making guide on acute respiratory illness in athletes(BMJ Publishing Group, 2024-09) Mackie, Mark R.; Schwellnus, Martin Peter; Thornton, Jane S.No abstract available.Item What impact have the IOC medical consensus statements made on athlete health? A survey of medical commissions from National Olympic/ Paralympic Committees and International Sports Federations(BMJ Publishing Group, 2024-04) Fortington, Lauren Victoria; Badenhorst, Marelise; Derman, Wayne; Emery, Carolyn; Pasanen, Kati; Schwellnus, Martin Peter; Verhagen, Evert; Finch, Caroline F.BACKGROUND: The International Olympic Committee (IOC) Medical and Scientific Commission has supported collating and sharing evidence globally by developing sports medicine consensus statements (‘Statements’'). Publishing the Statements requires substantial resources that must be balanced by use and impact on policy and practice. This study aimed to gain a better understanding of awareness and uptake of the Statements globally through a survey of the National Olympic Committees (NOC), National Paralympic Committees (NPC) and International Federations (IF). METHOD: A cross-sectional survey of medical commission representatives from NOCs/NPCs/IFs. A structured questionnaire was distributed through the IOC head office, informed by prior research. Questions comprised a mix of closed and open-text responses with results presented descriptively by organisation type and total. RESULTS: 55 responses were included: 29 (52%) from NOC/ NPC representatives (response rate 14%) and 26 (47%) from IF representatives (response rate 63%). All Statements had been used by at least one respondent, with the Statement addressing concussion ranked highest (used by 33/55). The main barriers to use were financial limitations (n=21), club/sport culture and behaviours (n=19) and lack of understanding from coaches/team sport personnel (n=19). Participants believed the Statements were a successful strategy for improving athlete health (n=39/51 agree or strongly agree). CONCLUSION: There was clear support for the continued development of sports medicine guidance, including in the format of these Statements. To ensure Statements lead to demonstrable health benefits for athletes, input from athletes, coaches and supporting staff is needed, as well as clearer identification of the purpose and audience of each topic developed.