Transient receptor potential channels and exercise-associated muscle cramping : a tale of multiple complexities

In an important study published in 2010, Miller et al.[1] showed that the duration of muscle cramping was reduced by administration of oral pickle juice immediately following electrically induced muscle cramps in hypohydrated humans. The authors concluded that this effect could not be explained by rapid restoration of body fluids or electrolytes and suggested that it reflected a neutrally mediated reflex originating in the oropharyngeal region and inhibiting the firing of α motor neurons of the cramping muscle. This observation led to the hypothesis that the mechanism by which pickle juice attenuated exercise-induced muscle cramping (EAMC) may involve stimulation of transient receptor potential (TRP) channels. These TRP channels have been found in the upper gastrointestinal tract (GIT), including the oropharyngeal region. Here we explore some of the methodological considerations related to a novel approach to study EAMC in the laboratory, EAMC as a more complex clinical entity than previously considered, and the complexity of TRP channels and their possible role in EAMC.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1097-45982018-09-30Sports Medicin

Medical encounters among 94,033 race starters during a 16.1-km running event over 3 years in the Netherlands: SAFER XXVI

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 nature of MEs will be similar to other running events. STUDY DESIGN : Descriptive epidemiological study over 3 years of a 16.1-km (10-mile) running event. LEVEL OF EVIDENCE : Level 4. METHODS : We investigated a total of 94,033 race starters at the 2017-2019 Dam tot Damloop (16.1 km), a point-to-point road race from Amsterdam to Zaandam, the Netherlands. All MEs were recorded by race medical staff on race day each year. MEs were retrospectively coded by severity, organ system, and final specific diagnosis (2019 consensus statement definition on mass community-based events). Incidence (I) per 1000 starters (95% CIs) were calculated for all MEs and serious/life-threatening MEs. RESULTS : The overall incidence (per 1000 starters) of all MEs was 2.75 (95% CI, 2.44-3.11), the overall incidence of serious/life-threatening MEs was 1.20 (95% CI, 1.00-1.45; 44% of MEs). Heat illnesses accounted for most MEs: hypothermia I = 0.54 (95% CI, 0.41-0.71) and hyperthermia I = 0.46 (95% CI, 0.34-0.62). Central nervous system MEs were also common (dizziness/nausea, I = 0.79; 95% CI 0.63-0.99), followed by the cardiovascular system MEs (exercise-associated postural hypotension, I = 0.36; 95% CI, 0.26-0.51). CONCLUSION : The overall incidence of MEs was low compared with longer-distance races (21.1-90 km), but the incidence and relative frequency of serious/life-threatening MEs (44% of all MEs) was much higher. Heat illness (hypothermia and exertional heat stroke) accounted for most serious/life-threatening MEs. CLINICAL RELEVANCE : There is a need to implement prevention strategies and interventions by specialized medical practitioners in this and similar events.IOC Research Center (South Africa).https://journals.sagepub.com/home/SPHhj2022Sports Medicin

COVID-19 vaccination in athletes: ready, set, go…

In the fight against the COVID-19 global pandemic, the focus in 2021 has fortunately turned to vaccination strategies. The successful development of several vaccines, and their proven efficacy and short-term safety in large scale multinational trials against severe acute respiratory syndrome coronavirus 2 (SARS-CoV2), offers promise in controlling the pandemic. Many countries are now operationalising their vaccination programmes, and prioritising health-care workers and the most vulnerable individuals within the population—eg, the elderly and those with chronic health conditions.https://www.thelancet.com/journals/lanreshj2022Sports Medicin

Predictors of multiple injuries in individual distance runners : a retrospective study of 75,401 entrants in 4 annual races-SAFER XX

BACKGROUND: There are limited data on factors that predict an increased risk of multiple injuries among distance runners. The objective of this study was 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 21.1 km and 56.0 km races in South Africa with 75,401 consenting race entrants. Running-related injury data were collected retrospectively through an online pre-race medical screening questionnaire. The average number of injuries for each runner every year was calculated by taking a runner’s race entry history and injury history into account and categorizing entrants into 4 MIR categories (high, intermediate, low, and very low (reference)). Multiple logistic regression modeling (odds ratios) was used to determine whether the following factors were predictive of a high MIR (average > 1 injury/year): demographics, training and racing, chronic-disease history (composite chronic disease score (CCDS)), and history of allergies. RESULTS: Of all entrants, 9.2% reported at least 1 injury, and 0.4% of entrants were in the high MIR category; the incidence rate was 2.5 injuries per 10 runner-years (95% confidence interval (95%CI): 2.4 2.7). Significant factors predictive of runners in the high MIR category were: running for > 20 years: OR = 2.0 (95%CI: 1.3 3.1; p = 0.0010); a higher CCDS: OR = 2.2 (95%CI: 2.0 2.4; p < 0.0001); and a history of allergies: OR = 2.8 (95%CI: 2.0 3.8; p 20 years and those with multiple chronic diseases or a history of allergies were at higher risk of multiple running-related injuries. This high-risk group can be targeted for further study and possible injury-prevention interventions.https://www.journals.elsevier.com/journal-of-sport-and-health-science/Sports Medicin

COVID-19 vaccination in athletes: ready, set, go…

In the fight against the COVID-19 global pandemic, the focus in 2021 has fortunately turned to vaccination strategies. The successful development of several vaccines, and their proven efficacy and short-term safety in large scale multinational trials against severe acute respiratory syndrome coronavirus 2 (SARS-CoV2), offers promise in controlling the pandemic. Many countries are now operationalising their vaccination programmes, and prioritising health-care workers and the most vulnerable individuals within the population—eg, the elderly and those with chronic health conditions.https://www.thelancet.com/journals/lanreshj2022Sports Medicin

Recent acute pre-race systemic illness in runners increases the risk of not finishing the race : SAFER study V

AIM : There are limited data on the negative effects of exercise in athletes with acute infective illness. The aim of this study was to determine whether a recently diagnosed prerace acute illness in runners affects the ability to finish a race. METHODS : Runners were prospectively evaluated in the 3 days before the race for acute infective illness and then received participation advice using clinical criteria based on systemic or localised symptoms/signs. We compared the did-not-start and the did-not-finish frequencies of ill runners (Ill=172: localised=58.7%; systemic=41.3%) with that of a control group of runners (Con=53 734). RESULTS : Runners with a systemic illness were 10.4% more likely not to start compared with controls (29.6% vs 19.2%) (p=0.0073). The risk difference of not starting the race in runners who were advised not to run the race compared with controls was 37.3% (56.5% vs 19.2%, p<0.0001). Compared with controls, runners with illness had a significantly (p<0.05) greater risk (any illness (5.2% vs 1.6%), systemic illness (8.0% vs 1.6%), illness <24 hours before the race (11.1% vs 1.6%)) and relative risk (prevalence risk ratio) (any illness=3.4, systemic illness=4.9, systemic illness <24 hours before the race=7.0) of not finishing the race. CONCLUSIONS : Runners with prerace acute systemic illness, and particularly those diagnosed <24 hours before race day, are less likely to finish the race, indicating a reduction in race performance.IOC Research Centre, South Africa (partial funding) South African Medical Research Council (partial funding, statistical analysis)http://bjsm.bmj.comhb2017Sports Medicin

Risk factors for not finishing an ultramarathon : 4-year study in 23,996 race starters, SAFER XXI

BACKGROUND: Limited data support prerace 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 (56 km) race starters who completed a prerace medical screening questionnaire. Race day environmental conditions were recorded on race day. Univariate analyses of risk factors associated with the did-not-finish (DNF) included race day factors and prerace medical screening history. RESULTS: Risk factors for DNF amongst 23,996 starters during the 56 km race included older age and females (P<0.0001). After adjusting for age and sex, the following were significant univariate risk factors: fewer years of running (P<0.0001), less previous race experience (P<0.0001), less training/racing per week (P=0.0002), lower average weekly training distance (P=0.0016), slower race vs. training speed (P<0.0001), lack of allergies (P=0.0100) and average wet-bulb globe temperature (P<0.0001). CONCLUSIONS: Females, older age, training-related factors (less training/racing, average weekly training distance, race vs. training speed) and average wet-bulb temperature, were risk factors for not finishing an ultramarathon. The results may not only assist runners and coaches in race preparation, but also have clinical implications for the medical planning prior to races.IOC Research Centre (South Africa) and South African Medical Research Council (partial funding).https://www.minervamedica.it/en/journals/sports-med-physical-fitnesshj2023Sports Medicin

Leisure athletes at risk of medical complications : outcomes of pre-participation screening among 15,778 endurance runners - SAFER VII

OBJECTIVE : International guidelines for pre-participation screening of masters/leisure athletes to identify those that require medical assessment exist, but have not been implemented in mass-community based sports events. We determined the prevalence of runners who, according to these guidelines, would require a medical assessment before participating in a distance running event. METHODS : Participants of the 2012 Two Oceans races (21.1 and 56 km) in South Africa (n = 15,778) completed an online pre-race medical screening questionnaire using European pre-participation screening guidelines. We determined the prevalence of runners that would require a pre-race medical assessment, based on risk factors, symptoms, and disease. RESULTS : The pre-participation “self assessment of risk” screening identified 4,941 runners (31.3%; 95% CI 30.6–32.0) that would need to undergo a full pre-participation medical assessment prior to running, if the current pre-participation screening guidelines are applied. Although musculoskeletal complaints and prescription medication use were the main triggers for a medical assessment, 16.8% (n = 2657) runners should undergo medical evaluation for suspected cardiac disease based on the questionnaire results: 3.4% (n = 538) reporting existing CVD (very high risk) and 13.4% (n = 2119) reporting multiple CVD risk factors (high risk). Other possible risk factors were reported as follows: history of chronic diseases (respiratory = 13.1%, gastro-intestinal = 4.3%, nervous system = 3.8%, metabolic/endocrine = 3.5%, allergies = 13.9%); chronic prescription medication = 14.8%, used medication before or during races = 15.6%; past history of collapse during a race = 1.4%. CONCLUSIONS : Current guidelines identified that > 30% runners would require a full medical assessment before race participation – mainly linked to runners reporting musculoskeletal conditions. We suggest a revision of guidelines and propose that pre-race screening should be considered to identify runners with a “very high,” “high,” and “intermediate risk” for medical complications during exercise. Pre-race screening and educational intervention could be implemented to reduce medical complications during exercise.The study was partially funded by a research grant from the International Olympic Committee (IOC) Research Centre (South Africa) at the University of Pretoria.https://tandfonline.com/toc/ipsm202019-08-23hj2018Sports Medicin

Diagnosis and management of nasal obstruction in the athlete : a narrative review by subgroup B of the IOC Consensus Group on “Acute Respiratory Illness in the Athlete”

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 bronchoconstriction (EIB), while nasal conditions have received less attention. The nose has several important physiological functions for the athlete. Nasal conditions causing obstruction to airflow can compromise respiratory health in the athlete, negatively affect quality of life and sleep, cause mouth breathing and ultimately leading to inadequate recovery and reduced exercise performance. Nasal obstruction can be broadly classified as structural (static or dynamic) or mucosal. Mucosal inflammation in the nose (rhinitis) is the most frequent cause of nasal obstruction and is reported to be higher in athletes (21-74%) than in the general population (20-25%). This narrative review provides the sport and exercise medicine physician with a clinical approach to the diagnosis and management of common nasal conditions that can cause nasal obstruction, ultimately leading to improved athlete health and better sports performance.IOC Research Center (South Africa)http://www.minervamedica.it/it/riviste/sports-med-physical-fitness/index.php2022-06-22hj2022Sports Medicin

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. </jats:sec