Heat exhaustion in The Sun‐Herald City to Surf fun run

Abstract

Objective To investigate the relationship between motivational fac‐tors and physical and biological causes of heat exhaustion in fun run entrants. Design and setting Case‐control study, The Sun‐Herald City to Surf fun runs in Sydney in 1991 and 1992. Participants There were 63 732 race entrants who completed the run and received a finishing time; 79 runners with heat exhaustion and 310 age, sex and performance matched controls were enrolled in the study. Main outcome measure A diagnosis of heat exhaustion was made if a runner collapsed and, when first receiving medical care, had a rectal temperature of 38°C or higher. Results Two readily identifiable groups of runners were at high risk of heat exhaustion—accomplished non‐élite (preferred) runners and runners of good ability (Group A). The attack rate was highest among accomplished non‐élite runners, but a combination of a relatively high rate and the large number of entrants in Group A runners accounted for most cases. Four major risk factors for heat exhaustion were identified: motivation to exceed previous performance tar‐gets; failure to drink fluids during the run; failure of trained runners to acclimatise for the race by training in the warmer parts of the day; and previous history of heat exhaustion. Conclusion Information from this investigation will enable more effective targeting of educational prevention programs in The Sun‐Herald City to Surf fun run and provide baseline data for monitoring the effectiveness of these programs to modify high risk behaviour by participants.

Plasma Hsp72 is higher in runners with more serious symptoms of exertional heat illness

“…In the present study all hyperpyrexic patients were treated promptly with rapid cooling and were discharged on the same day with no residual eVects. Control runners were recruited to match as far as possible the known characteristics of runners who are susceptible to EHI (Lyle et al 1994), and there was no signiWcant diVerence in age or time to complete the event between control runners and patients. CNS patients took longer to cool compared to MILD patients, even though T rec immediately post race was similar in both groups.…”

“…These characteristics match those of runners at risk of EHI in the City to Surf race (Lyle et al 1994). Immediately after Wnishing the event, subjects proceeded to adjacent toilet/change rooms where they each inserted a disposable rectal probe (Mon-a-therm, Mallinckrodt Medical Inc, St Louis, USA) 10 cm beyond the anal sphincter and the T rec measurement was recorded without delay.…”

“…The annual Sun-Herald City to Surf Fun Run (City to Surf) conducted in Sydney, Australia has been the subject of several previous investigations into the causes of heat illness (Sutton et al 1972;Richards et al 1979a-c;Richards and Richards 1984;Lyle et al 1994). In recent years more than 50,000 participated in the event, a small number of whom require treatment for heat illness.…”

Knowledge and Belief Toward Heat Safety and Hydration Strategies Among Runners: A Preliminary Evaluation

“…[16][17][18][19] Moreover, a lack of adequate fluid intake may result in cardiovascular and thermoregulatory strain and increase the risk of EHI. 15,17,20 Despite the increased prevalence of surveillance studies at road-race events, [4][5][6]16 few researchers have investigated runners' intentions and actual behaviors on race day. Moreover, assessments of runners' knowledge of the aforementioned risk factors and the usefulness of a standardized education module to improve runners' knowledge are needed to explore methods that can help prevent incidents of EHI.…”