Forskning

July 26, 2018

Acute caffeine intake improves lower body resistance exercise performance with blood flow restriction

D B Souza et al, 2018. Acute caffeine intake improves lower body resistance exercise performance with blood flow restriction, Int J Sports Physiol Perform, published online.

ABSTRACT:
Purpose: The purpose of this study was to examine the effects of acute caffeine intake on physical performance in three sets of unilateral knee extension with blood flow restriction.

Methods: In a double-blind crossover design, 22 trained men ingested 6 mg/kg of caffeine (CAF) or a placebo (PLA), 1 hour prior to performing unilateral knee extension exercise with blood flow restriction until exhaustion (30% of 1RM).

Results: There was a significant difference in the number of repetitions between the CAF and PLA conditions in the 1^st set (28.3 ± 5.3 vs 23.7 ± 3.2; P=0.005), 2^nd set (11.6 ± 3.1 vs 8.9 ± 2.9; P=0.03), and total repetitions performed across the three sets (44.5 ± 9.4 vs 35.0 ± 6.6; P=0.001). Blood lactate was also significantly different (P=0.03) after exercise between the CAF (7.8 ± 1.1 mmol.L^-1) and PLA (6.0 ± 0.9 mmol.L^-1). In regard to pain perception, there was a difference between the CAF and PLA in the 2^nd (6.9 ± 1.5 vs 8.4 ± 1.4; P=0.04) and 3^rdsets (8.7 ± 0.4 vs 9.5 ± 0.6; P=0.01). No differences were found for perceived effort.

Conclusion: Acute caffeine intake increases performance, blood lactate concentration and reduces perception of pain in unilateral knee extension exercise with blood flow restriction.