Standardization indices of cardiac hypertrophy in weight lifters

In order to investigate further the use of standardization procedures to determine training effects on cardiac dimension and function, two groups of subjects were analysed noninvasively. A control group of sedentary men (n = 7) and an experimental group of weight lifters (n=12) volunteered for a standard M-mode echocardiographic assessment. Indices of cardiac function as well as absolute left ventricular dimensions and left ventricular mass were similar between the groups. Standardizing for body surface area and body weight separated the groups. The weight lifters were shown to have a more muscular left ventricular posterior wall. The weight lifters also demonstrated a dilated left ventricle when indexing for body surface area. All other dimensional and volumetric indices were non-significant. The present investigation underlines the need for matching control and experimental groups to biometric variables in order to avoid misinterpreting cardiac enlargement. There is evidence for a true relative hypertrophy in weight lifters as indicated by similar absolute cardiac dimensions and similar biometric variables. Therefore, when evaluating athletes engaged in a chronic pressure overload, cardiac hypertrophy indices should consider body surface area (BSA), body weight and lean body weight (LBW). Future work in this field should incorporate rigorous controls on all biometric variables for better interpretation of hypertrophy in relative or absolute terms.