Supplementation with a polyphenolic blend improves post-exercise strength recovery and
muscle soreness
Sammanfattning
Background: Exercise can initiate a cascade of inflammatory and oxidative stress-related events
leading to delayed onset muscle soreness. Polyphenols possess antioxidant and anti-inflammatory
properties.
Objective: The current study examined the effects of a proprietary polyphenolic blend (PB), containing
catechins and theaflavins, on exercise performance and recovery following an eccentric exercise
challenge.
Design: Male participants (18-35 years of age) received placebo or PB at a low dose (PB-L, 1,000
mg/d) or high dose (PB-H, 2,000 mg/d) for 13 weeks. During the 13th week of supplementation,
participants completed an eccentric exercise (40 min downhill treadmill run) followed by a strength
assessment (peak torque on isokinetic leg extensions) pre-exercise, and 24, 48, and 96 h post-
exercise. Muscle soreness (subjective questionnaire), markers of muscle stress (cortisol and
creatine phosphokinase [CK]), and antioxidant capacity (ferric reducing ability of plasma [FRAP]) were
also assessed.
Results: PB-H attenuated the decrease in peak torque observed in the placebo group from pre-
exercise to 48 h (p=0.012) and 96 h (p=0.003) post-exercise. At 48 h post-exercise, PB-H reduced
whole body and hamstring soreness (p=0.029) versus placebo. Chronic consumption of PB improved
serum FRAP (p=0.039). As expected, serum cortisol and CK increased from pre- to post-exercise in all
groups; however, by 96 h, cortisol and CK levels returned to pre-exercise levels following PB
supplementation. At 96 h, the change in cortisol from pre- to post-exercise was significantly greater in
placebo versus PB-H (p=0.039).
Conclusion: These findings show that chronic consumption of PB improved antioxidant status,
reduced markers of muscle stress, and promoted strength recovery post-exercise