Core Temperature While Swimming In A Wetsuit During 1000-m Race Pace Swim

Abstract

Majority of fatalities that occur in the sport of triathlon happen during the swim portion of the race (Harris et al., 2010, JAMA). The potential risk of death while swimming has raised safety concerns. The governing body, USA Triathlon (USAT), has implemented guidelines related to water temperatures and the use of wetsuits. The varying water temperatures allow for a wide selection of wetsuits. Using a wetsuit while swimming in warm water may increase body heat storage which could increase core temperature. Currently, there are only limited data on the influence of triathlon wetsuits on core temperature when swimming in warm water while swimming a short distance at a somewhat hard swim pace (Aura et al., 2019, MSSE). PURPOSE: The purpose of this study was to examine core temperature while swimming a long distance (1000 m) at a fast pace in warm water (25.5 °C) while wearing a wetsuit. METHODS: Two experienced triathletes (mean ± standard deviation (SD), age 38.5 ± 23.3 years, height 1.83 ± 0.03 m, weight 80.1 ± 1.1 kg) participated in the study. At least 8 hours prior to attending the test session, participants swallowed an ingestible core temperature pill (BodyCap). Before beginning data collection, core temperature (Tc) data were transferred to a computer and sample rate was set to 0.1 Hz (1 sample every 10 s). Testing consisted of a self-directed warm up of 250-m followed by a 1000-m swim in an indoor pool (set to 25-m length) for each condition: no wetsuit (NW) and full sleeve wetsuit (FS). Participants swam at a self-selected pace at a “race pace” intensity (Borg Rating of Perceived Exertion = 16). Participants were required to rest until core temperature was within 0.5 °C of baseline before starting the next condition. Core temperature data were transferred to a computer after each swim. Average Tc of each swim was computed for analysis. RESULTS: The average core temperatures of NW and FS were 37.75 ± 0.11°C and 37.74 ± 0.46°C, respectively. The total swim time for the NW and FS conditions were 14:04 ± 1:43 and 13:05 ± 1:06 minutes. Mean stroke rate calculated for NW and FS were 30.12 ± 0.17 and 30.68 ± 0.45 strokes per minutes. Average swim speeds for NW and FS were 1.19 ± 0.15 and 1.28 ± 0.11 meters per second. CONCLUSIONS: Based upon the analysis of the results, the use of a wetsuit while swimming in warm water does not influence core temperature.