Monday, March 28, 2011

Study: Montmorency Cherry Juice Reduces Muscle Damage Caused By Intensive Strength Exercise

A recent study by the Sports and Exercise Science Research Centre at London South Bank University, London, UK, found that tart cherry juice reduces muscle damage caused by intensive strength exercise.  

PURPOSE: Montmorency cherries contain high levels of polyphenolic compounds including flavonoids and anthocyanins possessing anti-oxidant and anti-inflammatory effects. We investigated whether the effects of intensive unilateral leg exercise on oxidative damage and muscle function were attenuated by consumption of a Montmorency cherry juice concentrate using a crossover experimental design.

METHODS: 10 well-trained male overnight fasted athletes completed two trials of 10 sets of 10 single leg knee extensions at 80% one repetition maximum (1RM). Trials were separated by 2 weeks and alternate legs were used in each trial. Participants consumed each supplement (CherryActive®, CA or isoenergetic fruit concentrate, FC) for 7 d prior to and 48h after exercise. Knee extension maximum voluntary contractions (MVC) were performed pre, immediately, 24 and 48h after the damaging exercise. Venous blood samples were collected at each time point and serum analysed for creatine kinase activity (CK), nitrotyrosine, high sensitivity C reactive protein, total anti-oxidant capacity and protein carbonyls (PC). Two way repeated measures ANOVA were used for statistical analysis of the data.

RESULTS: MVC force recovery was significantly faster (24h: 90.9 ± 4.2, CA vs 84.9 ± 3.4, FC; 48h: 92.9±3.3, CA vs 88.5±2.9, FC; % of initial MVC; mean ?SEM; p<0.05) after CA than FC consumption. Only serum CK and PC increased significantly from baseline, peaking 24h after exercise (p<0.001). The exercise-induced increase in CK activity was not different between trials. However, both the percentage (24h post: 23.8±2.9, CA; 82.7±11.7, FC; %; p=0.013) and absolute (24h post: 0.31±0.03, CA; 0.60±0.08, FC; nmol/mg protein; p=0.079) increase in PC was lower in CA than FC trials.

CONCLUSIONS: Montmorency cherry juice consumption improved the recovery of isometric muscle strength after intensive exercise perhaps due to attenuation of the oxidative damage induced by the damaging exercise.

Click here for the study. 

No comments:

Post a Comment