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

We tested the hypothesis that dietary nitrate (NO3−)-rich beetroot juice (BR) supplementation could partially offset deteriorations in O2transport and utilization and exercise tolerance after blood donation. Twenty-two healthy volunteers performed moderate-intensity and ramp incremental cycle exercise tests prior to and following withdrawal of ∼450 ml of whole blood. Before donation, all subjects consumed seven 70-ml shots of NO3−-depleted BR [placebo (PL)] in the 48 h preceding the exercise tests. During the 48 h after blood donation, subjects consumed seven shots of BR (each containing 6.2 mmol of NO3−, n = 11) or PL ( n = 11) before repeating the exercise tests. Hemoglobin concentration and hematocrit were reduced by ∼8–9% following blood donation ( P < 0.05), with no difference between the BR and PL groups. Steady-state O2uptake during moderate-intensity exercise was ∼4% lower after than before donation in the BR group ( P < 0.05) but was unchanged in the PL group. The ramp test peak power decreased from predonation (341 ± 70 and 331 ± 68 W in PL and BR, respectively) to postdonation (324 ± 69 and 322 ± 66 W in PL and BR, respectively) in both groups ( P < 0.05). However, the decrement in performance was significantly less in the BR than PL group (2.7% vs. 5.0%, P < 0.05). NO3−supplementation reduced the O2cost of moderate-intensity exercise and attenuated the decline in ramp incremental exercise performance following blood donation. These results have implications for improving functional capacity following blood loss.

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Effects Of Beetroot Juice Components On Exercise Tolerance And Cardiometabolic Health In Individuals With Obesity

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000762496.89334.a2 ◽

2021 ◽

Vol 53 (8S) ◽

pp. 290-290

Author(s):

Christian E. Behrens ◽

Khandaker A. Ahmed ◽

Karina Ricart ◽

Braxton Linder ◽

Jose R. Fernandez ◽

...

Keyword(s):

Exercise Tolerance ◽

Cardiometabolic Health ◽

Beetroot Juice

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Dietary nitrate supplementation: effects on plasma nitrite and pulmonary O2 uptake dynamics during exercise in hypoxia and normoxia

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00068.2014 ◽

2014 ◽

Vol 307 (7) ◽

pp. R920-R930 ◽

Cited By ~ 66

Author(s):

James Kelly ◽

Anni Vanhatalo ◽

Stephen J. Bailey ◽

Lee J. Wylie ◽

Christopher Tucker ◽

...

Keyword(s):

Exercise Tolerance ◽

Moderate Intensity ◽

Beetroot Juice ◽

Moderate Intensity Exercise ◽

Exercise Tests ◽

Double Blind ◽

Dietary Nitrate ◽

Severe Intensity ◽

Rate Of Decline ◽

Plasma Nitrite

We investigated the effects of dietary nitrate (NO3−) supplementation on the concentration of plasma nitrite ([NO2−]), oxygen uptake (V̇o2) kinetics, and exercise tolerance in normoxia (N) and hypoxia (H). In a double-blind, crossover study, 12 healthy subjects completed cycle exercise tests, twice in N (20.9% O2) and twice in H (13.1% O2). Subjects ingested either 140 ml/day of NO3−-rich beetroot juice (8.4 mmol NO3; BR) or NO3−-depleted beetroot juice (PL) for 3 days prior to moderate-intensity and severe-intensity exercise tests in H and N. Preexercise plasma [NO2−] was significantly elevated in H-BR and N-BR compared with H-PL ( P < 0.01) and N-PL ( P < 0.01). The rate of decline in plasma [NO2−] was greater during severe-intensity exercise in H-BR [−30 ± 22 nM/min, 95% confidence interval (CI); −44, −16] compared with H-PL (−7 ± 10 nM/min, 95% CI; −13, −1; P < 0.01) and in N-BR (−26 ± 19 nM/min, 95% CI; −38, −14) compared with N-PL (−1 ± 6 nM/min, 95% CI; −5, 2; P < 0.01). During moderate-intensity exercise, steady-state pulmonary V̇o2 was lower in H-BR (1.91 ± 0.28 l/min, 95% CI; 1.77, 2.13) compared with H-PL (2.05 ± 0.25 l/min, 95% CI; 1.93, 2.26; P = 0.02), and V̇o2 kinetics was faster in H-BR (τ: 24 ± 13 s, 95% CI; 15, 32) compared with H-PL (31 ± 11 s, 95% CI; 23, 38; P = 0.04). NO3− supplementation had no significant effect on V̇o2 kinetics during severe-intensity exercise in hypoxia, or during moderate-intensity or severe-intensity exercise in normoxia. Tolerance to severe-intensity exercise was improved by NO3− in hypoxia (H-PL: 197 ± 28; 95% CI; 173, 220 vs. H-BR: 214 ± 43 s, 95% CI; 177, 249; P = 0.04) but not normoxia. The metabolism of NO2− during exercise is altered by NO3− supplementation, exercise, and to a lesser extent, hypoxia. In hypoxia, NO3− supplementation enhances V̇o2 kinetics during moderate-intensity exercise and improves severe-intensity exercise tolerance. These findings may have important implications for individuals exercising at altitude.

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Beetroot juice supplementation speeds O2uptake kinetics and improves exercise tolerance during severe-intensity exercise initiated from an elevated metabolic rate

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00295.2013 ◽

2013 ◽

Vol 305 (12) ◽

pp. R1441-R1450 ◽

Cited By ~ 85

Author(s):

Brynmor C. Breese ◽

Melitta A. McNarry ◽

Simon Marwood ◽

Jamie R. Blackwell ◽

Stephen J. Bailey ◽

...

Keyword(s):

Metabolic Rate ◽

Exercise Tolerance ◽

Near Infrared ◽

Order Type ◽

Moderate Intensity ◽

Type Ii ◽

Beetroot Juice ◽

Moderate Intensity Exercise ◽

Double Blind ◽

Severe Intensity

Recent research has suggested that dietary nitrate (NO3−) supplementation might alter the physiological responses to exercise via specific effects on type II muscle. Severe-intensity exercise initiated from an elevated metabolic rate would be expected to enhance the proportional activation of higher-order (type II) muscle fibers. The purpose of this study was, therefore, to test the hypothesis that, compared with placebo (PL), NO3−-rich beetroot juice (BR) supplementation would speed the phase II V̇o2kinetics (τp) and enhance exercise tolerance during severe-intensity exercise initiated from a baseline of moderate-intensity exercise. Nine healthy, physically active subjects were assigned in a randomized, double-blind, crossover design to receive BR (140 ml/day, containing ∼8 mmol of NO3−) and PL (140 ml/day, containing ∼0.003 mmol of NO3−) for 6 days. On days 4, 5, and 6 of the supplementation periods, subjects completed a double-step exercise protocol that included transitions from unloaded to moderate-intensity exercise (U→M) followed immediately by moderate to severe-intensity exercise (M→S). Compared with PL, BR elevated resting plasma nitrite concentration (PL: 65 ± 32 vs. BR: 348 ± 170 nM, P < 0.01) and reduced the V̇o2τpin M→S (PL: 46 ± 13 vs. BR: 36 ± 10 s, P < 0.05) but not U→M (PL: 25 ± 4 vs. BR: 27 ± 6 s, P > 0.05). During M→S exercise, the faster V̇o2kinetics coincided with faster near-infrared spectroscopy-derived muscle [deoxyhemoglobin] kinetics (τ; PL: 20 ± 9 vs. BR: 10 ± 3 s, P < 0.05) and a 22% greater time-to-task failure (PL: 521 ± 158 vs. BR: 635 ± 258 s, P < 0.05). Dietary supplementation with NO3−-rich BR juice speeds V̇o2kinetics and enhances exercise tolerance during severe-intensity exercise when initiated from an elevated metabolic rate.

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Influence of muscle oxygenation and nitrate-rich beetroot juice supplementation on O2 uptake kinetics and exercise tolerance

Nitric Oxide ◽

10.1016/j.niox.2020.03.007 ◽

2020 ◽

Vol 99 ◽

pp. 25-33 ◽

Cited By ~ 1

Author(s):

Stuart P. Cocksedge ◽

Brynmor C. Breese ◽

Paul T. Morgan ◽

Leonardo Nogueira ◽

Christopher Thompson ◽

...

Keyword(s):

Exercise Tolerance ◽

Uptake Kinetics ◽

Muscle Oxygenation ◽

Beetroot Juice ◽

O2 Uptake ◽

O2 Uptake Kinetics

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

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00017.2018 ◽

2018 ◽

Vol 315 (3) ◽

pp. R453-R460 ◽

Cited By ~ 5

Author(s):

Letizia Rasica ◽

Simone Porcelli ◽

Mauro Marzorati ◽

Desy Salvadego ◽

Alessandra Vezzoli ◽

...

Keyword(s):

Exercise Tolerance ◽

Healthy Subjects ◽

Slow Component ◽

Moderate Intensity ◽

Time To Exhaustion ◽

Beetroot Juice ◽

Obese Adolescents ◽

Physiological Variables ◽

Severe Intensity ◽

Ergogenic Effects

Previous studies showed a higher O2 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 O2 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/m2) 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 O2 cost of moderate-intensity exercise was not different in BR versus PLA (13.3 ± 1.7 vs. 12.9 ± 1.1 ml·min−1·W−1, P = 0.517). During severe-intensity exercise, signs of a reduced amplitude of the O2 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.

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