Author(s): HOELZ TELLINI TOLEDO, M., BADESSA, V.S.G., NARESSI, L.S., FERREIRA, R.E.S., QUARESMA, M.V.L., COLUCCI, J.A., NAKAMOTO, F.P., Institution: CENTRO UNIVERSITÁRIO SÃO CAMILO, Country: BRAZIL, Abstract-ID: 2455

INTRODUCTION:
Exercise increases core body temperature, which is necessary to optimize physiological mechanisms. However, its excessive increase may impair exercise (or physical) performance. Therefore, strategies aimed at mitigating excessive heat storage during exercise are of considerable practical and scientific interest. We aimed to evaluate the effect of the percooling technique, using a new cryotherapy vest on the 20-minute cycling time trial performance.
METHODS:
This is a randomized crossover clinical trial (ethics committee approval number 4.601.552). Inclusion criteria comprised both genders, ages 18 to 60 years old, cycling or triathlon experience of at least six months, and the ability to perform an all-out 20-minute time trial. The study required 3 visits to our laboratory. The first one included anthropometric measurement, a 24-hour dietary recall, and familiarization with the trial and the equipment (vest Spartacool®, K5 Cosmed® for gas analysis, and cycle ergometer WattBike®). The trial began with a 5-minute warm-up, followed by a 2-minute rest period in which the vest was placed and adjusted on the participant, as well as the all-out 20-minute trial. Free cadence and load were allowed to all participants at all times. Participants responded to the BORG CR10 rating of perceived exertion (RPE) scale and the thermal sensation scale every 2 minutes. Visits 2 and 3 were randomized for the use of the vest during the trial. Data normality was assessed using the Shapiro-Wilk test. Paired Student's t-test compared both conditions (wearing or not the vest). Data were analyzed using Jamovi® 2.3.21 version.
RESULTS:
Data of 11 enrolled subjects (6 males, 5 females) are presented as mean (SD). Age: 37.5 (15.5) years old; training experience: 3.14 (3.08) years; BMI: 23.1 (1.5) kg/m2; body fat %: 11.84 (5.87). Room temperature was 23.6 (0.8) degrees Celsius. We observed no differences in distance covered during the time trial (p = 0.483) with (11.3 ((1.38) km) or without the vest ((11.3 (1.25) km), mean power (p = 0.449; vest: 165 (52.5) W; no vest 165 (47.7) W); or peak power (p = 0.939; vest: 284 (94.1) W; no vest: 305 (105.8) W). On the other hand, all subjects reported feeling better when wearing the vest during the trial, which was corroborated by the delta (final minus initial) thermal sensation analysis (p = 0.005; vest: 1.60 (0.97); no vest: 3.20 (1.23)).
CONCLUSION:
Preliminary data showed that no differences in the 20-min cycling time trial performance or power were found between tests with and without the cryotherapy vest. In spite of these results, subjects reported lower delta thermal sensation. More data is necessary to elucidate the benefits of this new vest.