Blood pressure and forearm blood flow after multiple sets of a resistive exercise for the lower limbs

Postexercise hypotension after resistive exercises has been described, but its underlying mechanisms are not well known. This study observed the blood pressure (BP) and vascular conductance after multiple sets of a lower-body resistive exercise.

BP and forearm blood flow (FBF; venous occlusion plethysmography) were assessed at rest and during reactive hyperemia, before and during postexercise recovery (10 and 60 min) in 16 men assigned to experimental (EG; n=9) and control (CG; n=7) groups. The EG performed the bilateral knee extension (10 sets of 15 repetitions with 90% of 15 repetitions maximum), whereas CG stayed at rest.

No between-group differences were detected at rest in any of the variables (P>0.13). In EG, the systolic BP (mmHg) assessed 10 min after the exercise was significant compared with rest condition (104.4±1.5 vs. 111.3±2.0; P=0.011). The FBF (ml/100 ml/min/mmHg) and the forearm vascular conductance (FVC; ml/min/mmHg) in the postexercise recovery were lower than at rest in EG (FBF: rest=3.08±1.03, 10 min=2.21±0.68, P=0.007 and 60 min=2.33±0.47, P=0.018; FVC: rest=0.039±0.014, 10 min=0.029±0.008, P=0.02 and 60 min=0.030±0.006, P=0.03), but not in CG (FBF: resting=2.80±0.52, 10 min=2.87±0.53, P=0.22 and 60 min=2.97±0.73, P=0.14; FVC: resting=0.035±0.006, 10 min=0.029±0.010, P=0.32 and 60 min=0.029±0.013, P=0.13). No within-group (P=0.67) or between-group (P=0.11) changes were found in FBF and FVC during reactive hyperemia along postexercise recovery.

Multiple sets of a single-resistance exercise induced postexercise hypotension and decreased FBF, albeit vasodilatation capacity was probably preserved.