The Influence of Special Military Training on Left Ventricular Adaptation to Exercise in Elite Air Force Soldiers

J Cardiovasc Echogr. 2023 Apr-Jun;33(2):69-75. doi: 10.4103/jcecho.jcecho_67_22. Epub 2023 Aug 14.

Abstract

Purpose: The purpose of this study was to observe the influence of level physical training intensity on left ventricular (LV) adaptation in elite air force soldiers compared to regular basic military training.

Methods: The LV adaptation of special military physical training for elite air force soldiers was compared with basic military training for regular troops. A group of the nonmilitary subject was also evaluated as a control group. The presence of LV adaptation was evaluated using some echocardiography parameters, including LV mass index (LVMI), LV ejection fraction (LVEF), global longitudinal strain (GLS), and myocardial work index. The parameters of the myocardial work index include global constructive work (GCW), global wasted work (GWW), global work index (GWI), and global work efficiency (GWE).

Results: Forty-three elite air force soldiers underwent special military training, 43 regular troops underwent basic military training, and 23 nonmilitary subjects as a control group. Age, heart rate, blood pressure, and Cooper test results significantly differed among the three groups. Multivariate analysis among all groups showed that the level of physical training was associated with the LVMI (coefficient β = 6.061; 95% confidence interval [CI] = 1.91-10.22; P = 0.005), LVEF (coefficient β = -1.409; 95% CI = -2.41-[-0.41]; P = 0.006), LVGLS (coefficient β = 1.726; 95% CI = 1.20-2.25; P < 0.001), GWW (coefficient β = -13.875; 95% CI = -20.88-[-6.87]; P < 0.001), GWE (coefficient β = 0.954; 95% CI = 0.62-1.26; P < 0.001), GCW (coefficient β = 176.128; 95% CI = 121.16-231.10; P < 0.001), and GWI (coefficient β = 196.494; 95% CI = 144.61-248.38; P < 0.001).

Conclusions: Higher intensity of physical training observed in a special military training is associated with higher LV GLS, GWE, GCW, GWI, and lower GWW value suggesting greater physiological adaptation than the lower intensity training.

Keywords: Global myocardial work; high-intensity exercise; left ventricle adaptation; military training.