The effects of beetroot juice supplementation on indices of muscle damage following eccentric exercise

• Published in: European journal of applied physiology 2016-02, Vol.116 (2), p.353-362
• Main Authors: Clifford, Tom, Bell, Oliver, West, Daniel J., Howatson, Glyn, Stevenson, Emma J.
• Format: Article
• Language: English
• Subjects: Adult; Antioxidants; Antioxidants - administration & dosage; Antioxidants - pharmacology; Antioxidants - therapeutic use; Beta vulgaris - chemistry; Biomedical and Life Sciences; Biomedicine; Cytokines; Cytokines - blood; Dietary Supplements; Exercise; Growth factors; Human Physiology; Humans; Kinases; Leukocytes; Male; Muscle Contraction; Muscle Fatigue; Muscle function; Muscle, Skeletal - drug effects; Muscle, Skeletal - physiology; Musculoskeletal system; Myalgia - drug therapy; Myalgia - prevention & control; Nitrates; Occupational Medicine/Industrial Medicine; Original Article; Pain Threshold - drug effects; Phytochemicals; Plant Extracts - administration & dosage; Plant Extracts - pharmacology; Plant Extracts - therapeutic use; Sports Medicine; Tumor necrosis factor-TNF
• ISSN: 1439-6319; 1439-6327
• DOI: 10.1007/s00421-015-3290-x

Purpose Foods rich in antioxidant and anti-inflammatory phytochemicals might attenuate skeletal muscle damage; thus, the present study investigated whether consuming an antioxidant rich beetroot juice would attenuate the muscle-damaging effects of eccentric exercise. Methods Using a double blind, independent groups design, 30 recreationally active males were allocated to consume a high dose of beetroot juice (H-BT; 250 ml), a lower dose of beetroot juice (L-BT; 125 ml), or an isocaloric placebo (PLA; 250 ml) immediately (×3 servings), 24 (×2 servings) and 48 h (×2 servings) following completion of 100-drop jumps. Maximal isometric voluntary contractions (MIVC), countermovement jumps (CMJ), pressure pain threshold (PPT), creatine kinase (CK), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumour necrosis factor-α (TNF-α) were measured pre, post, 2 (blood indices only), 24, 48 and 72 h following the drop jumps. Results CMJ performance recovered quicker (relative to baseline) in H-BT vs. PLA at 48 (91.7 ± 12.2 vs. 74.4 ± 17.3 %; P  = 0.009, ES = 1.00) and 72 h postexercise (93.4 ± 7.7 vs. 86 ± 5.9 %; P  = 0.046, ES = 1.25). PPT was greater in both the H-BT and L-BT vs. PLA at 24, 48 and 72 h postexercise ( P   0.05). Conclusions Acute beetroot juice supplementation attenuated muscle soreness and decrements in CMJ performance induced by eccentric exercise; further research on the anti-inflammatory effects of beetroot juice are required to elucidate the precise mechanisms.