Nicola Sewry

University of Pretoria | UP · Sport Exercise Medicine and Lifestyle Institute

Background 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-se...

Objective: 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...

Background The influence of menstrual cycle phases (MCPs), menstrual irregularities (MI) and hormonal contraceptive (HC) use on injury among female athletes has been scrutinised. Existing systematic reviews investigating the effect of exposures affecting the endogenous reproductive hormone status on sporting injuries are limited in terms of the typ...

Background The influence of menstrual cycle phases (MCPs), menstrual irregularities (MI) and hormonal contraceptive (HC) use on injury among female athletes has been scrutinised. Existing systematic reviews investigating the effect of exposures affecting the endogenous reproductive hormone status on sporting injuries are limited in terms of the typ...

Purpose Performance indicators in women's rugby union are under-researched. The aim of this study was to describe the match activities and determine the predictors for winning/losing and points difference in the South African Rugby Union (SARU) Women's Premier Division competition. Methods During the 2021 and 2022 seasons, SARU-coded matches inclu...

Objective To determine if any gradual onset running-related injury (GORRI) was associated with any allergies, multiple allergies (allergies to animals, plants, medication), and allergy medication use. Design Cross-sectional descriptive study. Setting Two Oceans Marathons (56 km, 21.1 km), South Africa. Participants A total of 76 654 race entrant...

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 F...

Background: 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 (90km) globally, research on the epidemiology, clinical characteristics, and risk factors of entrants' lifetime hEAMC are scarce....

Objectives The aim of this study was to compare the incidence, severity, and burden of injury in starting and replacement players from professional men’s teams of five rugby unions. Methods Match injuries of greater than 24 h time-loss (including data on the severity, match quarter, event, body region) and player minutes of match exposure data wer...

Background Acute respiratory infections (ARinf) are the most common medical reason for athletes to miss training or competition. The influence that different pathogens have on the time to return-to-training (RTT) and return-to-full performance (RTFP) remains unknown. Objective To determine whether the time to RTT and RTFP following an ARinf differ...

Background There is a high incidence of medical encounters (MEs) and serious/life-threatening MEs in marathon road running races but injury and illness risk factors associated with MEs in these events have not been well investigated and will assist with injury and illness prevention. Objective To determine the independent risk factors that are ass...

Background The environment in which athletes compete impacts respiratory health and performance. Particulate Matter 2.5 (PM2.5) bypasses the body’s natural air filtration system and can result in acute and chronic respiratory illness. Athletes competing in environments with harmful PM levels might be disproportionately affected by high PM2.5 concen...

Background The prevalence of exercise-associated muscle cramping (EAMC) among ultramarathon runners is high. While the Comrades is one of the most popular mass community-based participation ultramarathons (90km) globally, research on the risk factors of entrants’ lifetime history (hEAMC) is scarce. Objective Investigate selected risk factors of hE...

Background Running and cycling are two of the most popular forms of physical exercise worldwide, with increased participation by older and female athletes. Gradual onset injuries (GOIs) are common in these two sports, requiring individually targeted injury prevention strategies. Objective To determine differences in the period prevalence (12 month...

The incidence of acute respiratory infections (ARinf), including SARS-CoV-2, in unvaccinated student rugby players during phases from complete lockdown during the COVID-19 pandemic to returning to competition is unknown. The aim of the study was to determine the incidence of ARinf (including SARS-CoV-2) during non-contact and contact phases during...

Purpose 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...

Objective To determine if two pre‐race screening tools (abbreviated tool of two open‐ended pre‐race medical screening questions [ABBR] vs. a full pre‐race medical screening tool [FULL]) identify running race entrants at higher risk for medical encounters (MEs) on race day. Methods 5771 consenting race entrants completed both an ABBR and a FULL pre...

Contact and collision sports are those sports in which contact with the opponent is common or intentional. This chapter systematically presents current knowledge regarding sports-related injuries within three contact sports (basketball, handball, and football) and three collision sports (rugby, ice hockey, and martial arts). Each sport is covered s...

Context: SARS-CoV-2 infection can affect the exercise response in athletes. Factors associated with the exercise response have not been reported. Objective: This study aimed to: 1) describe heart rate (HR), systolic blood pressure (SBP), and rating of perceived exertion (RPE) responses to exercise in athletes with recent SARS-CoV-2 infection, an...

BACKGROUND: The prevalence of a history of exercise-associated muscle cramps (hEAMC) among ultramarathon runners is high. While the Comrades is one of the most popular community-based mass participation ultramarathons (90km) globally, research on the epidemiology and clinical characteristics of entrants' lifetime hEAMC is scarce. PURPOSE: To descri...

Background: There is limited evidence available on contributing factors for gradual onset running-related injuries (GORRIs) in ultramarathon runners. The aim was to determine if selected risk factors were associated with a history of GORRIs in 90-km ultramarathon race entrants. Methods: Descriptive cross-sectional study. GORRI and medical data u...

Objectives: Currently there are five international screening tools that are recommended to identify individuals who require pre-exercise medical clearance to reduce the risk of medical encounters during exercise. Therefore, the aim was to determine the percentage of race entrants who are advised to obtain pre-exercise medical clearance and the obs...

Objectives To compare the performance of various diagnostic bronchoprovocation tests (BPT) in the assessment of lower airway dysfunction (LAD) in athletes and inform best clinical practice. Design Systematic review with sensitivity and specificity meta-analyses. Data sources PubMed, EBSCOhost and Web of Science (1 January 1990–31 December 2021)....

Objective: To determine independent risk factors associated with a history of exercise-associated muscle cramps (hEAMCs) in distance runner race entrants in a community-based mass participation event. Design: Cross-sectional study. Setting: 2012 to 2015, Two Oceans marathon races (21.1 and 56 km), South Africa. Participants: Seventy six thou...

The paper introduces the Healthy Environments for Athletes field campaign to measure environmental conditions (heat stress and allergenic agents) associated with endurance events.

Purpose: To determine factors predictive of prolonged return to training (RTT) in athletes with recent SARS-CoV-2 infection. Methods: Cross-sectional descriptive study. Athletes not vaccinated against COVID-19 (n = 207) with confirmed SARS-CoV-2 infection (predominantly ancestral virus and beta-variant) completed an online survey detailing the f...

Acute illnesses affecting the respiratory tract are common and form a significant component of the work of Sport and Exercise Medicine (SEM) clinicians. Acute respiratory illness (ARill) can broadly be classified as non-infective ARill and acute respiratory infections (ARinf). The aim of this consensus is to provide the SEM clinician with an overvi...

Objective To describe the incidence and transmission of SARS-CoV-2 infections in South African professional rugby union players in different phases of return-to-competition during a pandemic. Design Prospective cohort study. Methods Players reported their history of SARS-CoV-2 infection before / during a national competition, using an online ques...

Acute respiratory infections (ARinf) are common in athletes, but their effects on exercise and sports performance remain unclear. This systematic review aimed to determine the acute (short‐term) and longer‐term effects of ARinf, including SARS‐CoV‐2 infection, on exercise and sports performance outcomes in athletes. Data sources searched included P...

Acute respiratory illness (ARill) is common and threatens the health of athletes. ARill in athletes forms a significant component of the work of Sport and Exercise Medicine (SEM) clinicians. The aim of this consensus is to provide the SEM clinician with an overview and practical clinical approach to non-infective ARill in athletes. The Internationa...

Background There are limited data on the medical encounters (MEs) occurring during mass community-based running events of shorter distances (10-21.1 km). The aim of this study was to determine the incidence and nature of MEs during the largest mass participation running event in the Netherlands. Hypothesis We hypothesize that the incidence and nat...

Background: Exercise associated collapse (EAC) is a common medical encounter at distance running events. Risk factors associated with EAC are not well documented. The objective is to determine the overall incidence of EAC and identify risk factors associated with EAC in 21.1km and 56km runners. Methods: A cross-sectional analysis of 153208 race...

Objective To review risk factors associated with acute respiratory illness (ARill) in athletes, including non-infectious ARill and suspected or confirmed acute respiratory infections (ARinf). Design Systematic review. Data sources Electronic databases: PubMed-Medline, EbscoHost and Web of Science. Eligibility criteria Original research articles...

Objective To determine the incidence of acute respiratory illness (ARill) in athletes and by method of diagnosis, anatomical classification, ages, levels of performance and seasons. Design Systematic review and meta-analysis. Data sources Electronic databases: PubMed-Medline, EbscoHost and Web of Science. Eligibility criteria Original research a...

Objectives The aim of this study is to review the evidence available suggesting that environmental conditions represent a risk factor associated with non-infective acute respiratory illness in athletes. Design Systematic review. Methods PubMed, EBSCOhost and Web of Science (1st January 1990–31 July 2020) were searched systematically using keyword...

Exercise-induced laryngeal obstruction (EILO) is caused by paradoxical inspiratory adduction of laryngeal structures during exercise. EILO is an important cause of upper airway dysfunction in young individuals and athletes, can impair exercise performance and mimic lower airway dysfunction, such as asthma and/or exercise-induced bronchoconstriction...

Objective To determine the days until return to sport (RTS) after acute respiratory illness (ARill), frequency of time loss after ARill resulting in >1 day lost from training/competition, and symptom duration (days) of ARill in athletes. Design Systematic review and meta-analysis. Data sources PubMed, EBSCOhost, Web of Science, January 1990–July...

Objective: To determine whether the lifetime prevalence and clinical characteristics of exercise-associated muscle cramping (EAMC) differ between runners entering a 21.1- versus 56-km road race. Design: Cross-sectional study. Setting: The 2012 to 2015 Two Oceans Marathon races (21.1 and 56 km), South Africa. Participants: Participants were c...

Objectives To determine the prevalence of self-reported pre-race chronic medical conditions and allergies in ultramarathon race entrants and to explore if these are associated with an increased risk of race-day medical encounters (MEs). Methods Data from two voluntary open-ended pre-race medical screening questions (Q1 – history of allergies; Q2 -...

Objective There are limited data on factors that predict an increased risk of multiple injuries among distance runners. The objective of this study is to determine risk factors that are predictive of individual runners with a high annual multiple injury risk (MIR). Methods A retrospective, cross-sectional study at 4 annual (2012–2015) Two Oceans 2...

Background Race starting time is often staggered over several hours in large mass-participation endurance sports events. Athlete exposure to environmental conditions changes as wet-bulb-globe-temperature (WBGT) changes during race day. Slower participants may be exposed to changing environmental conditions for a longer duration. In most studies env...

Background There is a high incidence of medical encounters (MEs) in ultramarathon road running races but risk factors associated with MEs in events have not been well investigated. Objective To determine the independent risk factors for all medical encounters in a 90km ultramarathon running race. Design Retrospective clinical audit, cross-section...

Background Injury-related medical encounters (injMEs) are common in mass community-based participation cycling events, but there are limited data on the risk factors associated with injuries in endurance cycling events. Objective To determine the risk factors associated with injMEs in a mass community-based endurance cycling event. Design Retrosp...

Background Pre-race medical screening at endurance events has recently been suggested, but there are limited data on the use of pre-race questionnaire data to predict adverse events (defined as medical encounters or not finishing a race). Objective To determine if risk factors, that are identified from a pre-race medical screening questionnaire, a...

Background Serious/life-threatening medical encounters (sltMEs) occur during mass community-based events, with higher incidences in ultra-endurance events. Risk factors associated with sltMEs are under-investigated. Objective To determine independent risk factors for serious/life-threatening MEs in a 90 km ultramarathon running event. Design Retr...

Background Illness-related medical encounters (illMEs) are common in mass community-based participation cycling events, but there are limited data on risk factors associated with illMEs in endurance cycling events. Objective To determine the independent risk factors associated with illMEs in a mass community-based endurance cycling event. Design...

Background Recent data indicate that pre-race medical screening and education can reduce medical encounters (MEs) at an endurance running event. However, the relationship between the risk of MEs and specific risk factors from pre-race medical screening, together with race day factors, and has not been explored. Objective To determine the independe...

Objective To report the prevalence of lower airway dysfunction in athletes and highlight risk factors and susceptible groups. Design Systematic review and meta-analysis. Data sources PubMed, EBSCOhost and Web of Science (1 January 1990 to 31 July 2020). Eligibility criteria Original full-text studies, including male or female athletes/physically...

Introduction Trail running is characterized by elevation changes, with uneven and varying running surfaces. Risk factors that may predict gradual-onset running-related injuries (GORRIs) in short-distance trail running have not been explored. The objective was to determine risk factors that predict GORRIs in trail running race entrants who entered m...

Protection of the health of the athlete is required for high level sporting performance. Acute respiratory illness is the leading cause of illness and can compromise training and competition in athletes. To date the focus on respiratory health in athletes has largely been on acute upper respiratory infections and asthma / exercise induced bronchoco...

Objective: To determine the incidence and nature of illness-related medical encounters (MEs) at a 90-km, ultramarathon, mass, community-based, endurance running event. Design: Retrospective, descriptive epidemiological study. Setting: Comrades Marathon (90 km), South Africa. Participants: One lakh three thousand one hundred thirty-one race s...

Background: Limited data support pre-race medical screening to identify risk factors for not finishing an endurance running race. The aim of the study was to determine risk factors associated with not finishing an ultramarathon. Methods: A prospective, cross-sectional study of Two Oceans ultramarathon (56km) race starters who completed a pre-rac...

Background There are no data relating symptoms of an acute respiratory illness (ARI) in general, and COVID-19 specifically, to return to play (RTP). Objective To determine if ARI symptoms are associated with more prolonged RTP, and if days to RTP and symptoms (number, type, duration and severity) differ in athletes with COVID-19 versus athletes wi...

Objective To determine the prevalence of chronic prescription medication (CPM) use in distance runners (by age and sex) and to compare CPM use in 21.1km vs. 56km race entrants. Methods A cross-sectional study of 76654 race entrants who completed a pre-race medical screening questionnaire during race registration, which included questions on the us...

Background There are limited data on acute injury-related medical encounters (injuries) in endurance cycling events. Objective To determine the risk factors for injuries during a mass community-based endurance cycling event. Design Retrospective, cross-sectional study. Setting Cape Town Cycle Tour (109 km), South Africa. Participants 102 251 ra...

Purpose: There are limited data on risk factors associated with illness-related medical encounters (illMEs) in cycling events. The aim was to determine risk factors associated with illMEs in mass community-based endurance cycling events. Methods: A retrospective, cross-sectional study in the Cape Town Cycle Tour (109km), South Africa with 102251...

Background: Pre-race screening and risk stratification in recreational endurance runners may predict adverse events (AEs) during a race. Aim: To determine if pre-race screening and risk stratification predicts AEs during a race. Methods: 29585 participants (Male 71.1%, average age=42.1years; Female 28.9%, average age=40.2years) at the Two Ocea...

DOI: https://doi.org/10.17159/2078-516X/2019/v31i1a7466 Introduction: Exercise associated muscle cramping (EAMC) is a common clinical syndrome that requires medical attention during and after endurance running events. The incidence of EAMC during the 90km “Comrades” marathon has not been reported. The aim of this study was to document the incidence...

DOI: https://doi.org/10.17159/2078-516X/2019/v31i1a7466 Introduction: Rugby union is a contact sport resulting in injuries, which may increase the risk of future injury. This study aimed to investigate whether a player who sustained an injury in a previous season, had a higher risk of sustaining an injury in the following season. Methods: A prospe...

DOI: https://doi.org/10.17159/2078-516X/2019/v31i1a7466 Introduction: The 90km “Comrades” ultramarathon is a popular annual event but there are limited data on medical encounters during this race. The purpose of this study was to determine the incidence rate of medical encounters (both illness and injuries) over multiple years during the 90km “Comr...

DOI: https://doi.org/10.17159/2078-516X/2019/v31i1a7466 Introduction: Chronic injuries are common in recreational runners, and often interfere with training and competition. The aim of this study was to investigate risk factors associated with being “injury prone” in entrants for a mass community-based running event. Methods: Data from an online pr...

DOI: https://doi.org/10.17159/2078-516X/2019/v31i1a7466 Introduction: Trail running differs from road running because of uneven and varying running surfaces, larger changes in altitude and large elevation gains/losses. Injury patterns in trail running may differ from road running, but this has not been well studied. The aim was to determine the epi...

DOI: https://doi.org/10.17159/2078-516X/2019/v31i1a7466 Introduction: Trail running is characterized by “off-road” running on uneven and varying running surfaces perhaps predisposing runners to more acute injuries during races compared with road running. The aim of this study was to describe the epidemiology of race-day injury-related vs. illness-r...

Objectives To determine whether a team illness prevention strategy (TIPS) would reduce the incidence of acute illness during the Super Rugby tournament. Methods We studied 1340 male professional rugby union player seasons from six South African teams that participated in the Super Rugby tournament (2010–2016). Medical staff recorded all illnesses...

The content of the report is based on data collected by the SA Rugby Injury and Illness Surveillance and Prevention Project (SARIISPP) steering group.

The content of the report is based on data collected by the SA Rugby Injury and Illness Surveillance and Prevention Project (SARIISPP) steering group.

Objectives: Youth rugby union is a popular sport with a high injury incidence density (IID) and burden. This high risk has called for further research into the factors affecting the injuries in youth rugby. The aim of the study was to analyse time-loss IID and burden in multiple schoolboy rugby teams over a season and the potential factors associa...

Objectives Youth rugby is a popular sport in South Africa (SA) with a high injury incidence. The annual SA Rugby Youth Week tournaments attract the top age group players in the country providing a sample of players for reliable injury surveillance. The aim of the study was to analyse the changes in time‐loss injury rates at the SA Rugby Youth Week...

The content of the report is based on data collected by the SA Rugby Injury and Illness Surveillance and Prevention Project (SARIISPP) steering group.

Objectives Rugby has a high injury incidence and therefore BokSmart introduced the Safe Six injury prevention programme in 2014 in an attempt to decrease this incidence. In 2015, BokSmart used a ‘targeted marketing approach’ to increase the awareness and knowledge of the Safe Six. Therefore, the aim of this study was to determine the change in the...

Background The injury burden in collision sports is relatively high compared to other team sports. Therefore, participants in these sports would benefit by having effective injury prevention programs. Exercise-based interventions have successfully reduced injuries in soccer, but evidence on exercise-based interventions in tackle collision sports is...

Background Exercise-based interventions have consistently been associated with a reduction in injury rates in sports such as football. Although the injury burden in rugby union (‘rugby’) is high, such interventions have not been evaluated in rugby. Objective To evaluate the effectiveness of the BokSmart Safe Six on (i) the injury risk profile and...

Background The injury burden in rugby union is relatively high compared to other team sports. Therefore rugby would benefit by having effective injury prevention programmes. Exercise-based interventions have successfully reduced injuries in soccer studies, but evidence on exercise-based interventions in tackle collision sports, such as rugby, is li...

Background The injury burden in rugby union (‘rugby’) is high. While exercise-based injury prevention programmes have successfully reduced injuries in other sports such as football, there is minimal research on this topic in rugby union. Objective To evaluate the effectiveness and implementation of an exercise-based intervention (BokSmart Safe Six...