Left ventricular dimensions and mass using magnetic resonance imaging in female endurance athletes

Few published studies of left ventricular (LV) mass in female endurance athletes have been performed with M-mode echocardiography, which involves assumptions of LV geometry. Therefore, magnetic resonance imaging, a 3-dimensional technique, was used to examine LV mass, LV end-diastolic volume and mean wall thickness in female long distance runners (n = 13; mean age 29 years), cyclists (n = 12; mean age 26 years) and cross-country skiers (n = 11; mean age 24 years), and the findings were compared with sedentary control subjects (n = 10; mean age 27 years) matched for height and body weight. The physical characteristics for all subjects included height (mean 166 cm, and body weight (mean 56 kg). The percent body fat (mean 11.7) and maximal oxygen uptake (V̇O₂max, mean 63 ml · kg^-1 · min^-1) were similar (p >0.05) among all athletic groups, but significantly different from the control group (body fat, mean 22.5%; V̇O₂max, mean 35 ml · kg^-1 · min^-1). LV mass (mean 159 kg), LV end-diastolic volume (mean 122 ml), and mean wall thickness (mean 11.5 mm) were also similar among the athletic groups and significantly larger than the following control values: LV mass (mean 115 g), LV end-diastolic volume (mean 93 ml) and mean wall thickness (mean 9.8 mm). Ratios of LV mass to lean body weight were similar among all athletic groups, although athletic groups had larger ratios (p < 0.05) than the sedentary control subjects. LV mass/LV end-diastolic volume ratio was similar (p >0.05) among all groups. Our findings indicate that LV mass, LV end-diastolic volume and mean wall thickness are greater in endurance athletes than sedentary control subjects and that the increase in LV mass is proportional to the increase in LV end-diastolic volume.