Features of immediate adaptation of the circulatory system to static load in persons with different body mass index

Abstract

In the vast majority of sports, muscle activity is dynamic in nature, however, recently sports physiologists have been paying considerable attention to static exercises. The deep mechanisms of the phenomenon of static efforts have been studied since its discovery, but there are still many gaps in biological knowledge regarding the issue of the impact of static load on the functioning parameters of the circulatory system in individuals with different anthropometric characteristics. The purpose of the work is to study the influence of dosed static load on the parameters of the circulatory system during the early recovery period in people with different body mass indexes. During the study, 36 young men were examined, who were divided into two groups according to the body mass index (BMI) criterion – young men with a normal BMI (nBMI group, the average value of BMI in the group – 21.6), as well as young men with an increased BMI (group iBMI, the average value of BMI in the group is 28.1). Static load (SL) was modeled by maintaining a force equal to 50 % of the maximum static force for 15 seconds on a static dynamometer DS-200. Before exercise and within 3 minutes after its completion, the main parameters of central hemodynamics were measured in the examined persons using tetrapolar thoracic rheoplethysmography on the computerized diagnostic complex "Cardio+" (Ukraine). Statistical data processing was carried out using the computer program IBM SPSS Statistics (version 26), using non-parametric methods of evaluating the obtained results. We have established that in the initial state, young men with a normal body mass index differ from persons with an increased body mass index by a lower value of heart rate, total peripheral resistance and blood pressure, as well as higher values of stroke and minute blood volumes, stroke and cardiac indices. The dosed static load leads to the same nature of changes in the parameters of the circulatory system in all examined persons, regardless of the body mass index. Differences in body mass index affect only the degree of manifestation of certain changes. A more significant manifestation of the Lingard phenomenon was recorded in young men with an increased body mass index, as evidenced by a greater degree of deviation of the measured parameters of the circulatory system in response to static exercise.