Continuous and accumulated bouts of cycling matched by intensity and energy expenditure elicit similar acute blood pressure reductions in prehypertensive men

Abstract

The present study investigated differences in postexercise hypotension (PEH) after continuous versus accumulated isocaloric bouts of cycling. Ten pre-hypertensive men, aged 23 to 34 yrs, performed two bouts of cycling at 75% oxygen uptake reserve, with total energy expenditures of 400 kcal per bout. One exercise bout was performed continuously (CONTIN) and the other as two smaller bouts each expending 200 kcal (INTER1 and INTER2). Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and cardiac autonomic control were monitored in a supine position for 10 min before and 60 min after each exercise bout, and during a control session. Compared to control, blood pressure was significantly reduced after CONTIN (SBP: ∆-3.4 mmHg, P < 0.001; MAP: ∆-2.5 mmHg, P = 0.001), INTER1 (SBP: ∆-2.2 mmHg, P = 0.045) and INTER2 (SBP: ∆-4.4 mmHg, P < 0.001; DBP: ∆-2.7 mmHg, P = 0.045; MAP: ∆-3.3 mmHg, P = 0.001). The PEH was similar in CONTIN and INTER2, while INTER2 elicited greater PEH than INTER1 (SBP and MAP: ∆-2.0 and ∆-1.8 mmHg, respectively, P < 0.05). Increases in sympathovagal balance from baseline were inversely related to changes in SBP and DBP after CONTIN and INTER2 (r = -0.64 to -0.71; P = 0.021 to P = 0.047). These findings indicate similar amounts of PEH are observed when exercise is performed as a single 400 kcal exercise bout or 2 x 200 kcal bouts and that the exercise recovery pattern of cardiac autonomic activity may be important in eliciting PEH