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Benjamim CJR, Lopes da Silva LS, Valenti VE, Gonçalves LS, Porto AA, Tasinafo Júnior MF, Walhin JP, Garner DM, Gualano B, Bueno Júnior CR. Effects of dietary inorganic nitrate on blood pressure during and post-exercise recovery: A systematic review and meta-analysis of randomized placebo-controlled trials. Free Radic Biol Med 2024; 215:25-36. [PMID: 38403254 DOI: 10.1016/j.freeradbiomed.2024.02.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 01/15/2024] [Accepted: 02/10/2024] [Indexed: 02/27/2024]
Abstract
OBJECTIVES A systematic review with meta-analysis was completed to study the effects of dietary inorganic nitrate (NO3-) oral ingestion from vegetables and salts on blood pressure responses during and following exercise. BACKGROUND NO3- is a hypotensive agent with the potential to reduce blood pressure peaks during exercise and amplify exercise-induced hypotensive effects. Several randomized and controlled trials have investigated the effects of NO3- on hemodynamic responses to physical exercise, however this still has yet to be studied systematically. METHODS The searches were conducted on EMBASE, Medline, and SPORTSDiscus databases. The study included masked randomized controlled trials (RCTs) with participants ≥18 years old. The NO3-intervention group received at least 50 mg NO3-/day with similar sources amid NO3- and placebo conditions. Included studies reported systolic blood pressure (SBP) or diastolic blood pressure (DBP) values during or following exercise performance. RESULTS 1903 studies were identified, and twenty-six achieved the inclusion criteria. NO3- daily dosages ranged from 90 to 800 mg/day. Throughout exercise, SBP had smaller increases in the NO3- group (-2.81 mmHg (95%CI: -5.20 to -0.41), p=0.02. DBP demonstrated lower values in the NO3- group (-2.41 mmHg (95%CI: -4.02 to -0.79), p=0.003. In the post-exercise group, the NO3- group presented lower SBP values (-3.53 mmHg (95%CI: -5.65 to 1.41), p=0.001, while no changes were identified in DBP values between NO3- and placebo groups (p=0.31). Subgroup meta-analysis revealed that SBP baseline values, exercise type, duration of NO3- ingestion, and its dosages mediated blood pressure responses during and following exercise. CONCLUSIONS NO3- ingestion prior to exercise attenuated the increases in SBP and DBP during exercise, and increased the decline in SBP after exercise. These results are dependent on factors that moderate the blood pressure responses (e.g., health status, type of exercise, resting blood pressure values).
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Affiliation(s)
- Cicero Jonas R Benjamim
- Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
| | | | | | - Leonardo S Gonçalves
- School of Physical Education of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | | | | | - Jean-Philippe Walhin
- Centre for Nutrition, Exercise and Metabolism, University of Bath, Bath, United Kingdom
| | - David M Garner
- Cardiorespiratory Research Group, Department of Biological and Medical Sciences, Oxford Brookes University, Gipsy Lane, Oxford, OX3 0BP, United Kingdom
| | - Bruno Gualano
- Center of Lifestyle Medicine, Applied Physiology & Nutrition Research Group, University of São Paulo, Medical School (FMUSP), São Paulo, SP, Brazil
| | - Carlos R Bueno Júnior
- Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil; School of Physical Education of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
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Thurston TS, Weavil JC, Georgescu VP, Wan HY, Birgenheier NM, Morrissey CK, Jessop JE, Amann M. The exercise pressor reflex - a pressure-raising mechanism with a limited role in regulating leg perfusion during locomotion in young healthy men. J Physiol 2023; 601:4557-4572. [PMID: 37698303 PMCID: PMC10592099 DOI: 10.1113/jp284870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 08/15/2023] [Indexed: 09/13/2023] Open
Abstract
We investigated the role of the exercise pressor reflex (EPR) in regulating the haemodynamic response to locomotor exercise. Eight healthy participants (23 ± 3 years,V ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ : 49 ± 6 ml/kg/min) performed constant-load cycling exercise (∼36/43/52/98%V ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ ; 4 min each) without (CTRL) and with (FENT) lumbar intrathecal fentanyl attenuating group III/IV locomotor muscle afferent feedback and, thus, the EPR. To avoid different respiratory muscle metaboreflex and arterial chemoreflex activation during FENT, subjects mimicked the ventilatory response recorded during CTRL. Arterial and leg perfusion pressure (femoral arterial and venous catheters), femoral blood flow (Doppler-ultrasound), microvascular quadriceps blood flow index (indocyanine green), cardiac output (inert gas breathing), and systemic and leg vascular conductance were quantified during exercise. There were no cardiovascular and ventilatory differences between conditions at rest. Pulmonary ventilation, arterial blood gases and oxyhaemoglobin saturation were not different during exercise. Furthermore, cardiac output (-2% to -12%), arterial pressure (-7% to -15%) and leg perfusion pressure (-8% to -22%) were lower, and systemic (up to 16%) and leg (up to 27%) vascular conductance were higher during FENT compared to CTRL. Leg blood flow, microvascular quadriceps blood flow index, and leg O2 -transport and utilization were not different between conditions (P > 0.5). These findings reflect a critical role of the EPR in the autonomic control of the heart, vasculature and, ultimately, arterial pressure during locomotor exercise. However, the lack of a net effect of the EPR on leg blood flow challenges the idea of this cardiovascular reflex as a key determinant of leg O2 -transport during locomotor exercise in healthy, young individuals. KEY POINTS: The role of the exercise pressor reflex (EPR) in regulating leg O2 -transport during human locomotion remains uncertain. We investigated the influence of the EPR on the cardiovascular response to cycling exercise. Lumbar intrathecal fentanyl was used to block group III/IV leg muscle afferents and debilitate the EPR at intensities ranging from 30% to 100%V ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ . To avoid different respiratory muscle metaboreflex and arterial chemoreflex activation during exercise with blocked leg muscle afferents, subjects mimicked the ventilatory response recorded during control exercise. Afferent blockade increased leg and systemic vascular conductance, but reduced cardiac output and arterial-pressure, with no net effect on leg blood flow. The EPR influenced the cardiovascular response to cycling exercise by contributing to the autonomic control of the heart and vasculature, but did not affect leg blood flow. These findings challenge the idea of the EPR as a key determinant of leg O2 -transport during locomotor exercise in healthy, young individuals.
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Affiliation(s)
- Taylor S. Thurston
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT
| | - Joshua C. Weavil
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, UT
| | - Vincent P. Georgescu
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT
| | - Hsuan-Yu Wan
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | | | | | - Jacob E. Jessop
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | - Markus Amann
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, UT
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Tan R, Baranauskas MN, Karl ST, Ortiz de Zevallos J, Shei RJ, Paris HL, Wiggins CC, Bailey SJ. Effects of dietary nitrate supplementation on peak power output: Influence of supplementation strategy and population. Nitric Oxide 2023; 138-139:105-119. [PMID: 37438201 DOI: 10.1016/j.niox.2023.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/14/2023]
Abstract
Increasing evidence indicates that dietary nitrate supplementation has the potential to increase muscular power output during skeletal muscle contractions. However, there is still a paucity of data characterizing the impact of different nitrate dosing regimens on nitric oxide bioavailability and its potential ergogenic effects across various population groups. This review discusses the potential influence of different dietary nitrate supplementation strategies on nitric oxide bioavailability and muscular peak power output in healthy adults, athletes, older adults and some clinical populations. Effect sizes were calculated for peak power output and absolute and/or relative nitrate doses were considered where applicable. There was no relationship between the effect sizes of peak power output change following nitrate supplementation and when nitrate dosage when considered in absolute or relative terms. Areas for further research are also recommended including a focus on nitrate dosing regimens that optimize nitric oxide bioavailability for enhancing peak power at times of increased muscular work in a variety of healthy and disease populations.
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Affiliation(s)
- Rachel Tan
- Department of Sports Medicine, Pepperdine University, Malibu, CA, 90263, USA.
| | - Marissa N Baranauskas
- Department of Human Physiology & Nutrition, University of Colorado, Colorado Springs, CO, 80918, USA
| | - Sean T Karl
- Department of Sports Medicine, Pepperdine University, Malibu, CA, 90263, USA
| | | | - Ren-Jay Shei
- Indiana University Alumni Association, Indiana University, Bloomington, IN, 47408, USA
| | - Hunter L Paris
- Department of Sports Medicine, Pepperdine University, Malibu, CA, 90263, USA
| | - Chad C Wiggins
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Stephen J Bailey
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, LE11 3TU, UK
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Grosicki GJ, Flatt AA, Cross BL, Vondrasek JD, Blumenburg WT, Lincoln ZR, Chall A, Bryan A, Patel RP, Ricart K, Linder BA, Sanchez SO, Watso JC, Robinson AT. Acute beetroot juice reduces blood pressure in young Black and White males but not females. Redox Biol 2023; 63:102718. [PMID: 37120928 PMCID: PMC10172749 DOI: 10.1016/j.redox.2023.102718] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 04/08/2023] [Accepted: 04/24/2023] [Indexed: 05/02/2023] Open
Abstract
A complex interplay of social, lifestyle, and physiological factors contribute to Black Americans having the highest blood pressure (BP) in America. One potential contributor to Black adult's higher BP may be reduced nitric oxide (NO) bioavailability. Therefore, we sought to determine whether augmenting NO bioavailability with acute beetroot juice (BRJ) supplementation would reduce resting BP and cardiovascular reactivity in Black and White adults, but to a greater extent in Black adults. A total of 18 Black and 20 White (∼equal split by biological sex) young adults completed this randomized, placebo-controlled (nitrate (NO3-)-depleted BRJ), crossover design study. We measured heart rate, brachial and central BP, and arterial stiffness (via pulse wave velocity) at rest, during handgrip exercise, and during post-exercise circulatory occlusion. Compared with White adults, Black adults exhibited higher pre-supplementation resting brachial and central BP (Ps ≤0.035; e.g., brachial systolic BP: 116(11) vs. 121(7) mmHg, P = 0.023). Compared with placebo, BRJ (∼12.8 mmol NO3-) reduced resting brachial systolic BP similarly in Black (Δ-4±10 mmHg) and White (Δ-4±7 mmHg) adults (P = 0.029). However, BRJ supplementation reduced BP in males (Ps ≤ 0.020) but not females (Ps ≥ 0.299). Irrespective of race or sex, increases in plasma NO3- were associated with reduced brachial systolic BP (ρ = -0.237, P = 0.042). No other treatment effects were observed for BP or arterial stiffness at rest or during physical stress (i.e., reactivity); Ps ≥ 0.075. Despite young Black adults having higher resting BP, acute BRJ supplementation reduced systolic BP in young Black and White adults by a similar magnitude, an effect that was driven by males.
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Affiliation(s)
- Gregory J. Grosicki
- Biodynamics and Human Performance Center, Georgia Southern University, Armstrong Campus, Savannah, GA, USA
| | - Andrew A. Flatt
- Biodynamics and Human Performance Center, Georgia Southern University, Armstrong Campus, Savannah, GA, USA
| | - Brett L. Cross
- Biodynamics and Human Performance Center, Georgia Southern University, Armstrong Campus, Savannah, GA, USA
| | - Joseph D. Vondrasek
- Biodynamics and Human Performance Center, Georgia Southern University, Armstrong Campus, Savannah, GA, USA
| | - Wesley T. Blumenburg
- Biodynamics and Human Performance Center, Georgia Southern University, Armstrong Campus, Savannah, GA, USA
| | - Zoe R. Lincoln
- Biodynamics and Human Performance Center, Georgia Southern University, Armstrong Campus, Savannah, GA, USA
| | - Amy Chall
- Department of Diagnostic and Therapeutic Services, Georgia Southern University, Armstrong Campus, Savannah, GA, USA
| | - Anna Bryan
- Department of Diagnostic and Therapeutic Services, Georgia Southern University, Armstrong Campus, Savannah, GA, USA
| | - Rakesh P. Patel
- Department for Pathology and Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Karina Ricart
- Department for Pathology and Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Braxton A. Linder
- Neurovascular Physiology Laboratory, Auburn University, Auburn, AL, USA
| | - Sofia O. Sanchez
- Neurovascular Physiology Laboratory, Auburn University, Auburn, AL, USA
| | - Joseph C. Watso
- Cardiovascular and Applied Physiology Laboratory, Florida State University, Tallahassee, FL, USA
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Tan R, Baranauskas MN, Karl ST, Ortiz de Zevallos J, Shei RJ, Paris HL, Wiggins CC, Bailey SJ. Effects of dietary nitrate supplementation on muscular power output: Influence of supplementation strategy and population. Nitric Oxide 2023:S1089-8603(23)00047-2. [PMID: 37244391 DOI: 10.1016/j.niox.2023.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 05/18/2023] [Indexed: 05/29/2023]
Abstract
Increasing evidence indicates that dietary nitrate supplementation has the potential to increase muscular power output during skeletal muscle contractions. However, there is still a paucity of data characterizing the impact of different nitrate dosing regimens on nitric oxide bioavailability its potential ergogenic effects across various population groups. This narrative review discusses the potential influence of different dietary nitrate supplementation strategies on nitric oxide bioavailability and muscular power output in healthy adults, athletes, older adults and some clinical populations. Areas for further research are also recommended including a focus individualized nitrate dosing regimens to optimize nitric oxide bioavailability and to promote muscular power enhancements in different populations.
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Affiliation(s)
- Rachel Tan
- Department of Sports Medicine, Pepperdine University, Malibu, CA, 90263, USA.
| | - Marissa N Baranauskas
- Department of Human Physiology & Nutrition, University of Colorado, Colorado Springs, CO, 80918, USA
| | - Sean T Karl
- Department of Sports Medicine, Pepperdine University, Malibu, CA, 90263, USA
| | | | - Ren-Jay Shei
- Indiana University Alumni Association, Indiana University, Bloomington, IN, 47408, USA
| | - Hunter L Paris
- Department of Sports Medicine, Pepperdine University, Malibu, CA, 90263, USA
| | - Chad C Wiggins
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Stephen J Bailey
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, LE11 3TU, UK
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Bordonie NC, Saunders MJ, de Zevallos JO, Kurti SP, Luden ND, Crance JH, Baur DA. Dietary nitrate supplementation enhances heavy load carriage performance in military cadets. Eur J Appl Physiol 2023; 123:91-102. [PMID: 36175576 DOI: 10.1007/s00421-022-05056-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 09/20/2022] [Indexed: 01/07/2023]
Abstract
PURPOSE To determine the effects of dietary nitrate (NO3-) supplementation on physiological responses, cognitive function, and performance during heavy load carriage in military cadets. METHODS Ten healthy males (81.0 ± 6.5 kg; 180.0 ± 4.5 cm; 56.2 ± 3.7 ml·kg·min-1 VO2max) consumed 140 mL·d-1 of beetroot juice (BRJ; 12.8 mmol NO3-) or placebo (PL) for six d preceding an exercise trial, which consisted of 45 min of load carriage (55% body mass) at 4.83 km·h-1 and 1.5% grade, followed by a 1.6-km time-trial (TT) at 4% grade. Gas exchange, heart rate, and perceptual responses were assessed during constant-load exercise and the TT. Cognitive function was assessed immediately prior to, during, and post-exercise via the psychomotor vigilance test (PVT). RESULTS Post-TT HR (188 ± 7.1 vs. 185 ± 7.4; d = 0.40; p = 0.03), mean tidal volume (2.15 ± 0.27 vs. 2.04 ± 0.23; p = 0.02; d = 0.47), and performance (770.9 ± 78.2 s vs. 809.8 ± 61.4 s; p = 0.03; d = 0.63) were increased during the TT with BRJ versus PL. There were no effects of BRJ on constant-load gas exchange or perceptual responses, and cognitive function was unchanged at all time points. CONCLUSION BRJ supplementation improves heavy load carriage performance in military cadets possibly as a result of attenuated respiratory muscle fatigue, rather than enhanced exercise economy.
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Affiliation(s)
- Nicholas C Bordonie
- Department of Kinesiology, James Madison University, Harrisonburg, VA, 22807, USA
| | - Michael J Saunders
- Department of Kinesiology, James Madison University, Harrisonburg, VA, 22807, USA
| | - Joaquin Ortiz de Zevallos
- Department of Kinesiology, School of Health and Human Development, University of Virginia, Charlottesville, VA, 22904, USA
| | - Stephanie P Kurti
- Department of Kinesiology, James Madison University, Harrisonburg, VA, 22807, USA
| | - Nicholas D Luden
- Department of Kinesiology, James Madison University, Harrisonburg, VA, 22807, USA
| | - Jenny H Crance
- Infirmary, Virginia Military Institute, Lexington, VA, 24450, USA
| | - Daniel A Baur
- Department of Human Performance and Wellness, Virginia Military Institute, 208 Cormack Hall, Lexington, VA, 24450, USA.
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Tan R, Black M, Home J, Blackwell J, Clark I, Wylie L, Vanhatalo A, Jones AM. Physiological and performance effects of dietary nitrate and N-acetylcysteine supplementation during prolonged heavy-intensity cycling. J Sports Sci 2022; 40:2585-2594. [PMID: 36759944 DOI: 10.1080/02640414.2023.2176052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 01/24/2023] [Accepted: 01/30/2023] [Indexed: 02/11/2023]
Abstract
The purpose of this study was to investigate effects of concurrent and independent administration of dietary nitrate (NO3-), administered as NO3--rich beetroot juice (BR; ~12.4 mmol of NO3-), and N-acetylcysteine (NAC; 70 mg·kg-1) on physiological responses during prolonged exercise and subsequent high-intensity exercise tolerance. Sixteen recreationally active males supplemented with NO3--depleted beetroot juice (PL) or BR for 6 days and ingested an acute dose of NAC or maltodextrin (MAL) 1 h prior to performing 1 h of heavy-intensity cycling exercise immediately followed by a severe-intensity time-to-exhaustion (TTE) test in four conditions: 1) PL+MAL, 2) PL+NAC, 3) BR+MAL and 4) BR+NAC. Pre-exercise plasma [NO3-] and nitrite ([NO2-]) were elevated following BR+NAC and BR+MAL (both P < 0.01) compared with PL+NAC and PL+MAL; plasma [cysteine] was increased in PL+NAC and BR+NAC (both P < 0.01) compared to PL+MAL. Muscle excitability declined over time during the prolonged cycling bout in all conditions but was better preserved in PL+NAC compared to BR+NAC (P < 0.01) and PL+MAL (P < 0.05). There was no effect of supplementation on subsequent TTE . These findings indicate that co-ingestion of BR and NAC does not appreciably alter physiological responses during prolonged heavy-intensity cycling or enhance subsequent exercise tolerance.
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Affiliation(s)
- Rachel Tan
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, UK
| | - Matthew Black
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, UK
| | - Joseph Home
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, UK
| | - Jamie Blackwell
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, UK
| | - Ida Clark
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, UK
| | - Lee Wylie
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, UK
| | - Anni Vanhatalo
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, UK
| | - Andrew M Jones
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, UK
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Tan R, Pennell A, Price KM, Karl ST, Seekamp-Hicks NG, Paniagua KK, Weiderman GD, Powell JP, Sharabidze LK, Lincoln IG, Kim JM, Espinoza MF, Hammer MA, Goulding RP, Bailey SJ. Effects of Dietary Nitrate Supplementation on Performance and Muscle Oxygenation during Resistance Exercise in Men. Nutrients 2022; 14:nu14183703. [PMID: 36145080 PMCID: PMC9504620 DOI: 10.3390/nu14183703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 08/31/2022] [Accepted: 09/05/2022] [Indexed: 11/16/2022] Open
Abstract
The purpose of the current study was to assess the effects of acute and short-term nitrate (NO3−)-rich beetroot juice (BR) supplementation on performance outcomes and muscle oxygenation during bench press and back squat exercise. Fourteen recreationally active males were assigned in a randomized, double-blind, crossover design to supplement for 4 days in two conditions: (1) NO3−-depleted beetroot juice (PL; 0.10 mmol NO3− per day) and (2) BR (11.8 mmol NO3− per day). On days 1 and 4 of the supplementation periods, participants completed 2 sets of 2 × 70%1RM interspersed by 2 min of recovery, followed by one set of repetitions-to-failure (RTF) at 60%1RM for the determination of muscular power, velocity, and endurance. Quadriceps and pectoralis major tissue saturation index (TSI) were measured throughout exercise. Plasma [NO3−] and nitrite ([NO2−]) were higher after 1 and 4 days of supplementation with BR compared to PL (p < 0.05). Quadriceps and pectoralis major TSI were not different between conditions (p > 0.05). The number of RTF in bench press was 5% greater after acute BR ingestion compared to PL (PL: 23 ± 4 vs. BR: 24 ± 5, p < 0.05). There were no differences between BR and PL for RTF for back squat or power and velocity for back squat or bench press (p > 0.05). These data improve understanding on the ergogenic potential of BR supplementation during resistance exercise.
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Affiliation(s)
- Rachel Tan
- Department of Sports Medicine, Pepperdine University, Malibu, CA 90263, USA
- Correspondence: ; Tel.: +1-3105067041
| | - Adam Pennell
- Department of Sports Medicine, Pepperdine University, Malibu, CA 90263, USA
| | - Katherine M. Price
- Department of Sports Medicine, Pepperdine University, Malibu, CA 90263, USA
| | - Sean T. Karl
- Department of Sports Medicine, Pepperdine University, Malibu, CA 90263, USA
| | | | | | - Grant D. Weiderman
- Department of Sports Medicine, Pepperdine University, Malibu, CA 90263, USA
| | - Joanna P. Powell
- Department of Sports Medicine, Pepperdine University, Malibu, CA 90263, USA
| | - Luka K. Sharabidze
- Department of Sports Medicine, Pepperdine University, Malibu, CA 90263, USA
| | | | - Justin M. Kim
- Department of Sports Medicine, Pepperdine University, Malibu, CA 90263, USA
| | | | - Maya A. Hammer
- Department of Sports Medicine, Pepperdine University, Malibu, CA 90263, USA
| | - Richie P. Goulding
- Laboratory for Myology, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, 1081 HZ Amsterdam, The Netherlands
| | - Stephen J. Bailey
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK
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