The effect of local precooling of the predominantly stressed muscles prior high-performance exercise under normal conditions

Abstract

Whereas humans sustain strict homeostatic range of body core temperature, skin and peripheral muscles may experience some variations in temperature. Recently, many studies were devoted to investigate effect of body precooling on physical performance, especially involving precooling of body core. However, no golden standard exists to study such associations, so protocols differ across a wide variety of ambient temperature, methods of assessment, precooling medium, parameters being evaluated and type of performance. Despite many different variables as well as existing confusing data, there is general strong need to clearly determine the effects of lower limbs precooling on power output during maximal performance of short duration. This Master's Thesis hereby presents an attempt to evaluate the appropriateness of application of local muscle precooling with cooling packs derived by EMCOOLS through the measurement of power output during “all-out” ergometer test (known as Wingate Anaerobic Test that measures peak and anaerobic power, and anaerobic capacity) at neutral ambient conditions. The secondary goal of present study is to provide recommendations of scientific background enhancing physical performance of skeletal muscles that could be of great value for widely considered athletes and indications of combining precooling with regular professional preparation before sport events. The above aims were achieved by means of research conducted in IMSB Institute in Südstadt from June to September 2017, in which a group of ten volunteers was involved and submitted to standardized Wingate test rocedure with and without precooling with precooling packs with continuous measurement of power output and cardiophysiological parameters, such as heart rate, systolic and diastolic blood pressure, body temperature and blood lactate concentration. The research was basically designed to verify the relevance of hypothesis that precooling intervention of quadriceps applied prior to Wingate test influences power output and associated indices in neutral ambient conditions defined as ± 20°C. The observations reported through the study were in opposition to primarily assumptions. More particularly, precooling intervention significantly impaired power output measured continuously along 30 seconds Wingate test, although anaerobic capacity, anaerobic power, fatigue index, peak and mean power, and hear rate demonstrated tendency towards decline, but not significant. In summary, precooling significantly decreased power output during anaerobic Wingate test, particularly in neutral ambient conditions. In contrast, such procedure could provide beneficial effect only in hot humid conditions or for performance of long duration. With respect to feasibility, cooling packs derived by EMCOOLS may be regarded as the best practice methods, however some discrepancies within this study highlight further need of investigation towards determination of effects of quadriceps precooling on anaerobic performance of short duration.