Betalain-Rich Concentrate Supplementation Improves Exercise Performance and Recovery in Competitive Triathletes

Abstract

INTRODUCTION: Beetroot juice has been shown to have ergogenic effects on endurance exercise due to its high nitrate concentration, which increases mitochondrial coupling and blood flow. Another possible reason for the ergogenic effects of beetroot could be the abundance of betalains, which have been shown to have anti-oxidant and anti-inflammatory properties at rest, and could therefore be responsible for part of the ergogenic effects of beetroot during exercise. PURPOSE: We aimed to determine the effects of a betalain-rich concentrate (BRC) of beetroots, containing no sugars or nitrates, on exercise performance and recovery. METHODS: Twenty-two (9 men and 13 women) triathletes (38 ± 11 yrs) completed two double-blind, cross-over, randomized trials (BRC and placebo) starting 7 days apart. Each trial was preceded by 6 days of supplementation with 100 mg·d-1 of BRC or placebo. On the 7th day of supplementation, exercise trials commenced 120 min after ingestion of 50mg BRC or placebo and consisted of 40 min of cycling (75±5 %VO2max) followed by a 10-km running time trial (TT). Subjects returned 24 h later to complete a 5-km running TT to assess recovery. RESULTS: 10-km TT duration (49.5±8.9 versus 50.8±10.3 min, p=0.03) was faster with the BRC treatment. Despite running faster, average heart rate and ratings of perceived exertion were not different between treatments. 5-km TT duration (23.2±4.4 versus 23.9±4.7 min, p=0.003), 24 h after the 10-km TT, was faster in 17 of the 22 subjects with the BRC treatment. Creatine kinase, a muscle damage marker, increased less (40.5±22.5 versus 49.7±21.5 U·L-1, p=0.02) from baseline to after the 10-km TT and subjective fatigue increased less (-0.05±6.1 versus 3.23±6.1, p=0.05) from baseline to 24 h after the 10-km TT with BRC. CONCLUSION: BRC supplementation improved 10-km TT performance in competitive male and female triathletes. Improved 5-km TT performances 24 h after the 10-km TT and the attenuated increase of CK and fatigue, suggest an increase in recovery while taking BRC. Supported by a grant from VDF FutureCeuticals, Incorporated.