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

PURPOSE: 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.

METHODS: 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.

RESULTS: 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.

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