|Abstract or Summary
- The purpose of this study was to compare the myocardial structure and
function among endurance athletes (n.12), powerlifters/steroid users (n=5),
powerlifters/non-steroid users (n=6), and sedentary controls (n=4).
All subjects had a M-mode echocardiographic examination of their left
ventricles under resting conditions. The echocardiographic measurements
recorded and analyzed were of the left ventricular posterior wall at diastole
and systole, left ventricular internal diameter at diastole and systole, and
inter-ventricular septal thickness at diastole and systole. Myocardial function
measurements consisting of left ventricle ejection time, left ventricular mass,
mean ventricular contractile force, and percent fractional shortening were
also recorded and analyzed. A One Way Analysis of Variance was used to
analyze the data for statistical significance. A Tukey's HSD post-hoc test was
used to determine statistical significance between the groups.
A significant difference (p =0.02) was found for inter-ventricular septal
thickness during diastole. All three athletic groups had significantly thicker
inter-ventricular septa' thickness during diastole as compared to the controls.
Power lifters/steroid users had the thickest inter-ventricular septal thickness
(18.7 mm), followed by endurance athletes (18.6 mm), and powerlifters/nonsteroid
users (16.5 mm). Overall, powerlifters/steroid users had the thickest
walls at systole and diastole, while endurance athletes had the greatest
internal diameters relative to the size of the left ventricle.
Statistically significant differences among the groups were found for all
four myocardial functional parameters: left ventricular ejection time (p = 0.03),
left ventricular mass (p = 0.002), mean ventricular contractile force of (p
0.0013), and percent fractional shortening (p = 0.05). Power lifters/steroid
users had the fastest left ventricular ejection times, largest left ventricular
mass, greatest mean ventricular contractile force, and greatest percent
fractional shortening. Endurance athletes had the slowest left ventricular
ejection times, second largest left ventricular mass, lowest mean ventricular
contractile force, and third lowest percent fractional shortening.
The results indicated that not all individuals participating in high level
endurance or powerlifting training and competition demonstrated complete
adaptations in myocardial structure and function. Power lifters/steroid users
however, demonstrated myocardial functional adaptations that were
significantly different from powerlifters/non-steroid users, endurance athletes,
The results of this study cannot attribute these changes either to the
use of large amounts of anabolic steroids, or long-term, high-intensity training
and competition in powerlifting. However, the study identified alterations in
myocardial functions in powerlifters/steroid users, and contributes to the
existing body of knowledge regarding the use of anabolic steroids by