Cardio-vascular changes during graded exercise.

In the present study cardio-vascular adaptation to graded exercise was studied in untrained male medical students. The subjects were given two grades of exercise each lasting for about five minutes with a rest of fifteen minutes in between on a mechanically braked bicycle ergometer. There was a statistically significant rise in the heart rate during both the exercise sessions. This rise was persistent even after fifteen minutes of rest following the second session. The systolic blood pressure also showed a statistically significant rise in both the sessions. However, the diastolic blood pressure showed a significant drop in the second exercise session. Both these changes could possibly be attributed to sustained release of epinephrine.