The Effect of Added Mass on Pulmonary Function

A comparative study of the volume-speed parameters of the human external respiration system was carried out under the influence of an additional weight load: a body armor weighing 11 kg and a backpack weighing 15 kg. The nature of changes in the main spirometric parameters under the influence of an added mass is typical for restrictive disorders of pulmonary function. A marked decrease in forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) values was observed when performing the test with a protective vest. In the conditions of a combination of body armor and a backpack, these changes were more pronounced (p < 0.01). At the same time, there were no significant changes in the Tiffno index values (FEV1/FVC). In addition, a significant decrease in the values of maximum voluntary ventilation (MVV) was revealed by 8.1% under the influence of body armor, and by 18.5% with a combination of a vest and a backpack relative to the control (p < 0.01). A significant correlation was shown between the maximum force of contraction of the inspiratory muscles and the maximum voluntary ventilation of the lungs both in the control and with an additional weight load. It is possible that inspiratory muscles training, aimed at increasing their strength and endurance, can be an effective strategy for minimizing the adverse effects of increased weight load when performing work with special protective equipment in various areas of human professional activity.