Heat stress and dehydration in kendo.

AIM: This study aimed to analyze sweat rate, water percentage alteration, and temperature variation during kendo practice in order to relate the thermal stress induced by such sports and draw recommendations for its secure practice.

METHODS

Participants were 12 male individuals. The studied variables were: age, weight, stature, body mass index, fat percentage, water loss percentage, tympanic temperature, and sweat rate. Measures were obtained in one day of 120 min practice (T: 24.1 ± 2.5 °C; RH: 73 ± 8.5%) using obligatory training equipment.

RESULTS

The age of participants was on average 26 ± 6.2 years, stature 1.8 ± 0.03 m, weight 78 ± 13.7 kg, BMI 24.12 ± 4.03 kg/m² and fat percentage 15.7 ± 5.1%. Weight and temperature final values were significantly different from the initial ones (P<0.01). Estimated sweat rate was 0.35 L.h-1 (95% CI = [0.299; 0.400]) and estimated percentage of water loss was 0.946% (95% CI = [0.694; 1.174]).

CONCLUSION

Kendo practice using obligatory equipment significantly increases temperature, even when sweat rate and water loss percentage are low. The almost complete obstruction of the evaporative surface leads to heat accumulation, which may result in risks comparable to those of American football players. Thus, preventive measures must be established to minimize the risks of the combination among environment (tropical climate), equipment (bogu) and the high physiological demand of this sport in order to prevent greater damages to the health of practitioners.