Two-dimensional finite element model to study the effect of periodic physical exercise on temperature distribution in peripheral regions of human limbs

Abstract

The human body regulates the body core temperature at a uniform temperature to maintain the structure and function of various physical and physiological processes. The physical exertion causes thermal stress which can disturb these mechanisms of thermoregulation under various environmental conditions and can lead to impairment of physiological functions. In view of the above, a finite element model has been developed to study thermal stress in peripheral regions of human limbs during periodic exercise and rest. It is assumed that the subject is doing exercise periodically by taking rest at regular intervals. The human limb is assumed to be of cylindrical shape. The peripheral region of a limb is divided into three natural components, namely epidermis, dermis and subdermal parts. Appropriate boundary conditions have been framed based on physical conditions of the problem. Finite element has been employed along radial and angular directions, and the finite difference is employed for time variable to obtain the solution. The numerical results have been used to obtain temperature profiles and study the effect of light-, moderate- and vigorous-intensity activities on thermal distribution in human limbs under moderate and hot climatic conditions. The results obtained by the present model are in agreement with the physiological facts and can be employed to predict the amount of acclimatization and rest required to cope up with such thermal stresses. Such models can be developed further to obtain thermal information in human organs involving physical exercise. This thermal information can be useful for developing strategies for the time period of different intensities of physical exercise and rest required for optimum performance of sportsman, labourers, workers and military person. Also the thermal information obtained from such models can be useful for developing protocols for heat stress required for therapeutic purposes during infection and physical exercise prescriptions for healthy lifestyles.