Ankle systolic blood pressure following sub-maximal and maximal exercises in healthy young men

Although recent studies have compared the effect of progressive exercise tests to constant moderate work load tests on ankle systolic blood pressure (ASBP) and ankle to arm index (AAI) in claudicants, little is known about the relation of ASBP and AAI to work load in healthy young men. Fifteen normal volunteers were asked to cycle 40, 60, 80, 100% of VO2max. Ankle and humeral pressures were recorded simultaneously, at rest and 1 minute after the end of each test. Thereafter, AAI was calculated as the ratio of ankle to humeral systolic pressure. Compared to resting values: 134.8 +/- 13.9 mmHg, ASBP increased significantly following sub maximal tests up to 157.8 +/- 28.1 mmHg (p < 0.005), but was not increased following maximal exercise: 141.5 +/- 28.2 mmHg (NS). On the other hand, AAI showed a progressive decrease from 1.14 +/- 0.06 at rest to 1.06 +/- 0.08 (p < 0.005), but 0.98 +/- 0.07 (p < 0.005), to 0.84 +/- 0.06 (p < 0.005) and to 0.75 +/- 0.09 (p < 0.005) following 40, 60, 80 and 100% of VO2max respectively. In summary, AAI following exercise is inversely related to workload whereas ASBP is not. We suggest that when studying ankle systolic blood pressure response to heavy load exercises, results should always be compared to humeral pressure, and expressed as ankle to arms indexes.