Effect of using a sauna to limit heat acclimatisation decay in cooler climates

The effects of heat acclimatisation via moderate to high intensity exercise in the heat at 1-2 weeks result in lower heart rate (hr), tympanic temperature (tt), rate of perceived exertion (rpe), thermal sensation (ts) with a concurrent increase in sweat rate (sr) and sports specific performance potential. Alternative strategies such as passive heat exposure via sauna and hot water exposure; alone and in conjunction with exercise; have equally been shown to induce thermal stress adaptations and subsequence improvement in performance in cooler climates. However, heat acclimatisation is also prone to decay; reported at 2:1 days ratio away from the heat. Whilst current reported rapid acclimatisation strategies at 2-4 days upon re immersion to the heat are effective; they are not always realistic to an athlete’s competitive schedule. As such, to limit the decay of prior heat acclimation, a post exercise sauna (80 degrees celsius) was implemented in contrast to exercise only in cooler conditions at 20 degrees celsius. A one-way ANCOVA to determine statistical significance in markers of performance (p≤0.05) between a post exercise sauna group (S) N=10 and exercise only (NS) N=10 males; 32.65 years old ± 3.53. residing in the middle east; whilst controlling for pre-test scores reported significance F (2,17) =.4.89, P=≤.041 in post intervention ratings of RPE; 14 (S) and 16 (NS) upon return to running outside in thermal temperatures towards 36 degrees celsius. Other markers of performance were not significant whilst controlling for pre-test scores; hr, tt, ts, sr and distance covered in a 20-minute submaximal competitive run P=≥.05; limitations linked to familiarity with running, hydration and intensity of exercise in the cool may have been confounding effects. The findings of this paper suggest a relatively simple and time effective approach in which to maintain heat acclimation during periods away from the heat for partially or fully acclimatised athletes.