No Effect of Tart Cherry Juice or Pomegranate Juice on Recovery from Exercise-Induced Muscle Damage in Non-Resistance Trained Men.

Kirstie L Lamb,Elizabeth Johnson,Anthony Lynn,Jessica Denning,Mayur K Ranchordas,Faye Downing

doi:10.3390/nu11071593

Kirstie L Lamb, Elizabeth Johnson + Show 4 more

Open Access

https://doi.org/10.3390/nu11071593

Copy DOI

Journal: Nutrients	Publication Date: Jul 14, 2019
Citations: 27	License type: CC BY 4.0

Affiliation: Sheffield Hallam University, University of Sheffield

Abstract

Tart cherry juice (TC) and pomegranate juice (POM) have been demonstrated to reduce symptoms of exercise-induced muscle damage (EIMD), but their effectiveness has not been compared. This randomized, double-blind, parallel study compared the effects of TC and POM on markers of EIMD. Thirty-six non-resistance trained men (age 24.0 (Interquartile Range (IQR) 22.0, 33.0) years, body mass index (BMI) 25.6 ± 4.0 kg·m−2) were randomly allocated to consume 2 × 250 mL of: TC, POM, or an energy-matched fruit-flavored placebo drink twice daily for nine days. On day 5, participants undertook eccentric exercise of the elbow flexors of their non-dominant arm. Pre-exercise, immediately post-exercise, and at 24 h, 48 h, 72 h and 96 h post-exercise, maximal isometric voluntary contraction (MIVC), delayed onset muscle soreness (DOMS), creatine kinase (CK), and range of motion (ROM) were measured. The exercise protocol induced significant decreases in MIVC (p < 0.001; max decrease of 26.8%, 24 h post-exercise) and ROM (p = 0.001; max decrease of 6.8%, 72 h post-exercise) and significant increases in CK (p = 0.03; max increase 1385 U·L−1, 96 h post-exercise) and DOMS (p < 0.001; max increase of 26.9 mm, 48 h post-exercise). However, there were no statistically significant differences between treatment groups (main effect of group p > 0.05 or group x time interaction p > 0.05). These data suggest that in non-resistance trained men, neither TC nor POM enhance recovery from high-force eccentric exercise of the elbow flexors.

Highlights

Eccentric muscle contractions, which are a feature of many sports, can induce substantial muscle damage [1]
Each serving of pomegranate juice (POM) contained nearly three times more total phenolics than a serving of tart cherry juice (TC)
We found that neither juice accelerated recovery as determined by changes in maximal isometric voluntary contraction (MIVC), delayed onset muscle soreness (DOMS), range of motion (ROM), and creatine kinase (CK), relative to an energy-matched placebo drink

Summary

Introduction

Eccentric muscle contractions, which are a feature of many sports, can induce substantial muscle damage [1]. Typical symptoms of exercise-induced muscle damage (EIMD) include loss of force, a reduced range of motion (ROM), and the development of muscle soreness. Since these symptoms can impair subsequent performance, there is much interest in strategies that accelerate recovery from. The secondary phase is characterized by a large increase in intracellular Ca2+ , which: (i) activates calcium-dependent proteases that degrade muscle proteins [6], and (ii) triggers an inflammatory response [7]; a feature of these is an elevation in reactive oxygen species [8]. Since inflammation and reactive species are involved in the process of EIMD, numerous dietary factors with antioxidant and anti-inflammatory effects have been examined to determine whether they accelerate recovery from EIMD [3]

Objectives

Discussion

Conclusion