# Acute neuromuscular, metabolic, and perceptual responses to low-load isokinetic exercise under varying percentages of arterial occlusion pressure

## TL;DR

This study finds that 70% arterial occlusion during low-load exercise provides strong muscle and metabolic benefits with less perceived effort compared to higher occlusion levels.

## Contribution

Identifies 70% arterial occlusion pressure as an optimal balance between training effectiveness and comfort during low-load isokinetic exercise.

## Key findings

- Muscle activation and blood lactate increased significantly at 70% and 80% arterial occlusion pressure.
- Raising occlusion from 70% to 80% did not improve neuromuscular activation but increased perceived exertion.
- 70% arterial occlusion offers a practical compromise for effective and tolerable blood flow-restricted training.

## Abstract

To examine whether graded arterial occlusion pressure (AOP) during low-load isokinetic exercise differentially modulates neuromuscular activation, metabolic stress, and perceptual strain, and to identify an occlusion level that maximizes stimulus while minimizing perceived burden.

Twelve healthy young men (21.3 ± 1.6 years) completed four randomized, counterbalanced sessions under 0%, 60%, 70%, and 80% AOP. During each session, isokinetic knee extension/flexion was performed at a low load under the assigned occlusion condition. Muscle activation was quantified using surface EMG and expressed as %EMGmax. Capillary blood lactate (BLa) was assessed at baseline and during recovery, and rating of perceived exertion (RPE) was recorded immediately after exercise.

Occlusion pressure produced a clear dose–response pattern in metabolic stress and neuromuscular demand. Both %EMGmax and BLa increased with higher AOP, with the most consistent elevations occurring at ≥70% AOP (p < 0.05). Importantly, raising occlusion from 70% to 80% AOP did not provide additional gains in %EMGmax, whereas RPE increased significantly at 80% AOP compared with 70% AOP (p < 0.05).

Low-load isokinetic exercise performed at 70% AOP elicits robust neuromuscular and metabolic stimulation without additional gains relative to 80% AOP while imposing a substantially lower perceptual load. These findings support 70% AOP as a practical “compromise point” for acute BFRT prescription when balancing training stimulus and tolerability.