The effect on body composition by physical (in)activity

Abstract

Body composition, as a term that denotes the relative proportions of all major body components, is under a significant influence by exogenous factors. The aim of this study is to determine the degree of exogenous influence, i.e., the influence of physical activity as well as inactivity, on the development of body composition at both genders, by comparing the non-trained and differently-trained participants. The research encompasses 93 subjects, of which 48 are men and 45 women, divided into three categories: the physically inactive (30), the physically active (32), and the elite athletes (31). The body structure testing proce, dure has been conducted by means of bioelectrical impedance, namely the InBodi 720. For the purpose of this paper, two basic parameters of body composition have been utilized - body fat mass (BFM), and skeletal muscle mass (SMM) - from which the percentage and index values have been calculated, i.e., percentage of body fat mass (PBFM) and percentage of skeletal muscle mass (PSMM), and body fat mass index (BFMI), skeletal muscle mass index (SMMI), and muscle fat index (MFI) respectively. A series of difference analyses (MANOVA, ANOVA, T test) have specified the relations in question, and discriminant analysis has been used to determine the most important factors and their structure. For both genders, applied analysis has been employed to determine the general level differences between the examined groups at the level of p = 0.000. The noticed differences in women occur in BFM, SMM, PBFM, PSMM, BFMI, SMMI, and MFI at the level of p = 0.000 - 0.025, while in men they occur at the level of p = 0.000 - 0.012 for the same range of variables apart from SMMI where no statistically significant difference between the examined groups has been ascertained. Based on the overall results, we can claim that an increase in physical activity results in an improvement in body composition, which is best exemplified by the linear growth of the MFI variable, i.e., the quotient of muscle and fat component.