PROGRESSIVE EXERCISE TESTING IN CLOSED HEAD-INJURED SUBJECTS - COMPARISON OF EXERCISE APPARATUS IN ASSESSMENT OF A PHYSICAL CONDITIONING PROGRAM

Progressive exercise tests were performed on 12 closed head-injured subjects to determine 1) whether results differ when tests are performed on a treadmill, a bicycle ergometer, or mechanical stairs and 2) whether a 3-month general physical conditioning program results in an improvement in exercise performance. The subjects performed progressive exercise tests on each apparatus on entry into a residential transitional rehabilitation program and approximately 3 months later following participation ina physical conditioning program. On both the initial and 3-month exercise tests, maximal oxygen consumption (V̇O(2 max)) was significantly greater on the treadmill and the mechanical stairs than on the bicycle ergometer. The mean V̇O(2 max) was 74% of the predicted value on the initial exercise test and rose to 85% of the predicted value after the 3-month physical conditioning program. Oxygen consumption per kilogram of body weight at a given power output on a given apparatus showed no statistically significant difference between the initial and 3-month tests, indicating no change in exercise efficiency. On the 3-month test, a statistically significant decrease was noted in heart rate at rest and after the 4-minute period of recovery from maximal exercise on any given apparatus. The data obtained in this study indicate that 1) the treadmill and mechanical stairs are more suitable than the bicycle ergometer for assessing maximal exercise performance and 2) improved physical fitness following a physical conditioning program is associated with an improvement in cardiovascular function. The results indicate that progressive exercise tests in closed head-injured subjects can be used to 1) quantify the degree of physical deconditioning, 2) design a physical conditioning program, and 3) assess outcome goals of such a program.