Hypotension following mild bouts of resistance exercise and submaximal dynamic exercise

Abstract

Our purposes were (1) to examine resting arterial blood pressure following an acute bout of resistance exercise and submaximal dynamic exercise, (2) to examine the effects of these exercises on the plasma concentrations of atrial natriuretic peptide ([ANP]), and (3) to evaluate the potential relationship between [ANP] and post-exercise blood pressure. Thirteen males [24.3+/-(2.4) years] performed 15 min of unilateral leg press exercise (65% of their one-repetition maximum) and, I week later, approximately 15 min of cycle ergometry (at 65% of their maximum oxygen consumption). Intra-arterial pressure was monitored during exercise and for 1 h post-exercise. Arterial blood was drawn at rest, during exercise and at intervals up to 60 min post-exercise for analysis of haematocrit and [alphaANP]. No differences occurred in blood pressure between trials, but significant decrements occurred following exercise in both trials. Systolic pressure was approximately 20 mmHg lower than before exercise after 10 min, and mean pressure was approximately 7 mmHg lower from 30 min onwards. Only slight (non-significant) elevations in [alphaANP] were detected immediately following exercise, with the concentrations declining to pre-exercise values by 5 min post-exercise. We conclude that post-exercise hypotension occurs following acute bouts of either resistance or submaximal dynamic exercise and, in this investigation, that this decreased blood pressure was not directly related to the release of alphaANP.

Potential causes, mechanisms, and implications of post exercise hypotension

“…[13][14][15] However, its occurrence in normotensive humans is inconsistent. Although we have found that PEH can be detected in normotensive individuals, 16 it was found to be much less consistent and of lesser magnitude than in hypertensive individuals. This may be due to other compensatory mechanisms, such as the baroreflex, that are activated in normotensive subjects, and prevent the degree of PEH from affecting orthostatic tolerance.…”

“…Data from MacDonald et al 16 can often reach values of over 200 mm Hg. 2 Although it is usually reported that DBP changes little throughout changes in the exercise intensity, Palatini 3 has suggested that changes in DBP are more variable and can range from a slight decrease, due to the vasodilation of the muscle vasculature, to an increase of 10 to 20 mm Hg, presumably from the occlusion of blood flow caused by the forceful contractions of the exercising muscle.…”

“…In those studies that have observed a decline in blood pressure following exercise, the average decrement in pressure was approximately 8/9 (SBP/DBP) mm Hg in the normotensive population, 16,[20][21][22][23]25,[31][32][33][34][35] 14/9 mm Hg in the borderline hypertensive population [10][11][12]34,[36][37][38][39] and 10/7 mm Hg in the hypertensive population. 13 37 We recently examined the effects of the exercising muscle mass by comparing the PEH response to both leg and arm ergometry at the same relative intensity.…”

“…16,23,64,65 It should be noted that reductions in blood pressure in the seconds or minutes following resistance exercise can be attributed to the sudden perfusion of the previously occluded muscle mass and a transient pressure undershoot. 4 These decrements should not be confused with PEH, which is found in the prolonged minutes or hours after exercise.…”

“…These reductions were found after whole body circuit training 23,65 and prolonged unilateral leg press exercise. 16 Studies directly comparing the haemodynamic responses to aerobic and resistance exercise indicate that there is no difference in the magnitude or duration of the observed hypotension between exercise modalities. 16,23 In rodents, PEH has been found after spontaneous 67 and forced 49,68 running.…”