Ergogenic effects of beetroot juice supplementation during severe-intensity exercise in obese adolescents

Abstract

Previous studies showed a higher O cost of exercise, and therefore, a reduced exercise tolerance in patients with obesity during constant work rate (CWR) exercise compared with healthy subjects. Among the ergogenic effects of dietary nitrate ([Formula: see text]) supplementation in sedentary healthy subjects, a reduced O cost and enhanced exercise tolerance have often been demonstrated. The aim of this study was to evaluate the effects of beetroot juice (BR) supplementation, rich in [Formula: see text], on physiological variables associated with exercise tolerance in adolescents with obesity. In a double-blind, randomized crossover study, 10 adolescents with obesity (8 girls, 2 boys; age = 16 ± 1 yr; body mass index = 35.2 ± 5.0 kg/m) were tested after 6 days of supplementation with BR (5 mmol [Formula: see text] per day) or placebo (PLA). Following each supplementation period, patients carried out two repetitions of 6-min moderate-intensity CWR exercise and one severe-intensity CWR exercise until exhaustion. Plasma [Formula: see text] concentration was significantly higher in BR versus PLA (108 ± 37 vs. 15 ± 5 μM, P < 0.0001). The O cost of moderate-intensity exercise was not different in BR versus PLA (13.3 ± 1.7 vs. 12.9 ± 1.1 ml·min·W, P = 0.517). During severe-intensity exercise, signs of a reduced amplitude of the O uptake slow component were observed in BR, in association with a significantly longer time to exhaustion (561 ± 198 s in BR vs. 457 ± 101 s in PLA, P = 0.0143). In obese adolescents, short-term dietary [Formula: see text] supplementation is effective in improving exercise tolerance during severe-intensity exercise. This may prove to be useful in counteracting early fatigue and reduced physical activity in this at-risk population.

Acute beetroot juice supplementation improves exercise tolerance and cycling efficiency in adults with obesity

“…The main purpose of this study was to determine the effects of acute supplementation with inorganic dietary NO 3 − in the form of BRJ, on exercise tolerance and cardiometabolic health among healthy men and women with obesity. Although recent studies have been similar in scope (Beals et al, 2017;Lara et al, 2015;Lima Bezerra et al, 2019;Rasica et al, 2018), to our knowledge, this is the first to report such findings in this population. The secondary purpose of this study was to explore the potential mechanisms by which these effects might occur by separating potentially salubrious components of BRJ (inorganic dietary nitrate and antioxidants) by treatment arm.…”

“…This is perhaps most important in type II muscle fibers where O 2 delivery often lags behind O 2 demand ultimately leading to oxidative inefficiency and fatigue during severe-intensity exercise (Grassi, Rossiter, & Zoladz, 2015;McDonough, Behnke, Padilla, Musch, & Poole, 2005). Indeed, a similar study by Rasica et al illustrated a reduced rate of VO 2 increase during severe-intensity exercise with BRJ supplementation, in adolescents with obesity, suggesting improved efficiency (Rasica et al, 2018). The observed improvement in exercise tolerance with BRJ during high-intensity exercise is noteworthy considering that high-intensity interval training has been shown to be a highly effective intervention for improvement in weight and health status in individuals with obesity (Fisher et al, 2015;Gillen et al, 2016).…”

“…It remains to be determined if the improvements in exercise and health outcomes following BRJ intake are due to increases in nitrate, antioxidant capacity, or a synergistic effect of both (Georgiev et al, 2010;Kanner et al, 2001;Reddy, Alexander-Lindo, & Nair, 2005). To date, there have been very few clinical investigations into the efficacy of BRJ supplementation on obesity, although previous investigations have been similar in scope (Beals et al, 2017;Lara et al, 2015;Lima Bezerra et al, 2019;Rasica et al, 2018), to our knowledge there have been no clinical investigations specifically examining its effect on exercise tolerance in adults with obesity. Thus, the primary purpose of this study is to determine if BRJ supplementation improves exercise tolerance and markers of cardiometabolic health in individuals with obesity, and secondly to determine if the ergogenic and cardiometabolic health benefits of BRJ are due to increased nitric oxide bioavailability, increased antioxidant capacity, or a combination of these two.…”

A Narrative Review on the Potential of Red Beetroot as an Adjuvant Strategy to Counter Fatigue in Children with Cancer

“…As for other disease conditions, a recent study also found that beetroot juice improved exercise tolerance in obese adolescents, another population with poor aerobic capacity and exercise intolerance. This study found that beetroot juice could be used to combat the early onset of fatigue associated with exercise in this population [66]. Similarly, Berry et al and Curtis et al found that beetroot juice supplementation in individuals with chronic obstructive pulmonary disease (COPD) resulted in extended exercise time during submaximal exercise, decreased resting systolic blood pressure, lowered VO2 consumption during submaximal exercise, and decreased diastolic blood pressure [67,68].…”

Effect of acute nitrite infusion on contractile economy and metabolism in isolated skeletal muscle in situ during hypoxia

“…2016; Rasica et al . 2018). The present study evaluated the effects of nitrite infusion on the canine gastrocnemius muscle, which is a markedly oxidative muscle (Maxwell et al .…”