Effects of pre-cooling procedures on intermittent-sprint exercise performance in warm conditions

Abstract

The aim of this study was to determine whether pre-cooling procedures improve both maximal sprint and sub-maximal work during intermittent-sprint exercise. Nine male rugby players performed a familiarisation session and three testing sessions of a 2 x 30-min intermittent sprint protocol, which consisted of a 15-m sprint every min separated by free-paced hard-running, jogging and walking in 32 degrees C and 30% humidity. The three sessions included a control condition, Ice-vest condition and Ice-bath/Ice-vest condition, with respective cooling interventions imposed for 15-min pre-exercise and 10-min at half-time. Performance measures of sprint time and % decline and distance covered during sub-maximal exercise were recorded, while physiological measures of core temperature (T (core)), mean skin temperature (T (skin)), heart rate, heat storage, nude mass, rate of perceived exertion, rate of thermal comfort and capillary blood measures of lactate [La(-)], pH, Sodium (Na(+)) and Potassium (K(+)) were recorded. Results for exercise performance indicated no significant differences between conditions for the time or % decline in 15-m sprint efforts or the distance covered during sub-maximal work bouts; however, large effect size data indicated a greater distance covered during hard running following Ice-bath cooling. Further, lowered T (core), T (skin), heart rate, sweat loss and thermal comfort following Ice-bath cooling than Ice-vest or Control conditions were present, with no differences present in capillary blood measures of [La(-)], pH, K(+) or Na(+). As such, the ergogenic benefits of effective pre-cooling procedures in warm conditions for team-sports may be predominantly evident during sub-maximal bouts of exercise.

Influence of the ten sessionsof the whole body cryostimulationon aerobic and anaerobic capacity

“…The benefits of whole body cryostimulation were visible not only in significant changes of peak power but also in average power, total external work, and in the time to reach Pmax. Other authors also confirm the benefits of cooling, especially in relation to short, supramaximal exercise [33]. Our research showed a significantly higher plasma lactate concentration after progressive endurance test as well as in the Wingate test after cryogenic treatments.…”

“…On the contrary, Banfi et al [7] demonstrated that whole-body cryotherapy had no effect on hematological values of either red blood cell count or leukocytes and platelets. A positive influence of pre-cooling procedures on submaximal bouts of exercise in warm conditions was observed by Duffield and Marino [33], yet those experiments were related to application of ice and cold water. Also, the research of Uckert & Joch [37] indicated that cooling with ice-cooling vest applied 20 min before exercise increased running endurance in warm conditions.…”

“…Most researchers have addressed the effects of local cold treatments, where particular parts of the body were cooled or whole body was immersed in cold water on the level of chosen motor abilities or physical work capacity, under different temperatures [30][31][32][33][34][35][36]. Others evaluated the influence of cooling on the rate of recovery following injuries [19,22,27].…”

Salbutamol effects on systemic potassium dynamics during and following intense continuous and intermittent exercise

“…This is the first report of arterial [K + ] during HI int , comprising brief sprints repeated in bursts to simulate intense activity undertaken in many team sports (Bishop et al 2011 (Krustrup et al 2006;Wylie et al 2013;Mohr et al 2011;Mohr et al 2007;Duffield and Marino 2007;Mohr et al 2006;Struthers et al 1988). …”

“…The antecubital venous [K + ] reported during intense intermittent exercise varies, reaching 4.3 mM during squash (Struthers et al 1988), 5.1 mM during soccer (Krustrup et al 2006), and 5.5-6 mM during repeated intermittent sprint testing (Wylie et al 2013;Mohr et al 2011;Mohr et al 2007;Duffield and Marino 2007;Mohr et al 2006 O 2 peak for use on the same cycle ergometer in the subsequent experimental trials. All respiratory measurements were as previously described (Atanasovska et al 2014) .…”