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Nuzzo JL. Muscle Strength Preservation During Repeated Sets of Fatiguing Resistance Exercise: A Secondary Analysis. J Strength Cond Res 2024; 38:1149-1156. [PMID: 38781472 DOI: 10.1519/jsc.0000000000004794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
ABSTRACT Nuzzo, JL. Muscle strength preservation during repeated sets of fatiguing resistance exercise: A secondary analysis. J Strength Cond Res 38(6): 1149-1156, 2024-During sustained or repeated maximal voluntary efforts, muscle fatigue (acute strength loss) is not linear. After a large initial decrease, muscle strength plateaus at approximately 40% of baseline. This plateau, which likely reflects muscle strength preservation, has been observed in sustained maximal isometric and repeated maximal isokinetic contractions. Whether this pattern of fatigue occurs with traditional resistance exercise repetitions with free weights and weight stack machines has not been overviewed. Here, the aim was to determine whether the number of repetitions completed across 4 or more consecutive repetitions-to-failure tests exhibits the same nonlinear pattern of muscle fatigue. A secondary analysis was applied to data extracted as part of a recent meta-analysis on repetitions-to-failure tests. Studies were eligible if they reported mean number of repetitions completed in 4-6 consecutive repetitions-to-failure tests at a given relative load. Twenty-nine studies were included. Overall, the results show that the number of repetitions completed in consecutive repetitions-to-failure tests at a given load generally decreases curvilinearly. The numbers of repetitions completed in sets 2, 3, 4, 5, and 6 were equal to approximately 70, 55, 50, 45, and 45% of the number of repetitions completed in set 1, respectively. Longer interset rest intervals typically attenuated repetition loss, but the curvilinear pattern remained. From the results, a chart was created to predict the number of repetitions across 6 sets of resistance exercise taken to failure based on the number of repetitions completed in set 1. The chart is a general guide and educational tool. It should be used cautiously. More data from a variety of exercises, relative loads, and interset rest intervals are needed for more precise estimates of number of repetitions completed during repeated sets of fatiguing resistance exercise.
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Affiliation(s)
- James L Nuzzo
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia
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Hartley C, Carr A, Roberts SSH, Bredie WLP, Keast RSJ. Carbohydrate Oral Rinsing, Cycling Performance and Individual Complex Carbohydrate Taste Sensitivity. Nutrients 2024; 16:459. [PMID: 38337743 PMCID: PMC10857552 DOI: 10.3390/nu16030459] [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: 12/20/2023] [Revised: 01/31/2024] [Accepted: 02/02/2024] [Indexed: 02/12/2024] Open
Abstract
The aim of this pilot study was to determine the effect of individual complex carbohydrate taste sensitivity on cycling performance with complex carbohydrate oral rinsing. Ten male participants completed five cycling time trials in a fasted state with a seven-day washout period between each trial. Participants completed a fixed amount of work (738.45 ± 150.74 kJ) as fast as possible on a cycle ergometer while rinsing with an oral rinse for 10 s every 12.5% of the trial. An oral rinse (maltodextrin, oligofructose, glucose, sucralose or water control) was given per visit in a randomised, crossover, blinded design. Afterwards, participants had their taste assessed with three stimuli, complex carbohydrate (maltodextrin), sweet (glucose) and sour (citric acid), using taste assessment protocol to determine individual taste sensitivity status. Participants were subsequently grouped according to their complex carbohydrate taste sensitivity and complex carbohydrate taste intensity. There were no significant effects of the oral rinses on cycling performance time (p = 0.173). Participants who did not have improvements in exercise performance with the maltodextrin rinse experienced a stronger taste intensity with complex carbohydrate stimuli at baseline (p = 0.047) and overall (p = 0.047) than those who did have improvements in performance. Overall, a carbohydrate oral rinse was ineffective in significantly improving cycling performance in comparison with a water control. However, when participants were grouped according to complex carbohydrate taste intensity, differences in exercise performance suggest that individual sensitivity status to complex carbohydrates could impact the efficacy of a carbohydrate-based oral rinse.
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Affiliation(s)
- Claudia Hartley
- CASS Food Research Centre, Deakin University, Burwood Highway, Burwood, VIC 3125, Australia;
- Department of Food Science, University of Copenhagen, Rolighedsvej 26, 1958 Frederiksberg, Denmark;
| | - Amelia Carr
- Centre for Sport Research, Deakin University, Burwood Highway, Burwood, VIC 3125, Australia; (A.C.); (S.S.H.R.)
| | - Spencer S. H. Roberts
- Centre for Sport Research, Deakin University, Burwood Highway, Burwood, VIC 3125, Australia; (A.C.); (S.S.H.R.)
| | - Wender L. P. Bredie
- Department of Food Science, University of Copenhagen, Rolighedsvej 26, 1958 Frederiksberg, Denmark;
| | - Russell S. J. Keast
- CASS Food Research Centre, Deakin University, Burwood Highway, Burwood, VIC 3125, Australia;
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Tan SH, Khong TK, Selvanayagam VS, Yusof A. Central effects of mouth rinses on endurance and strength performance. Eur J Appl Physiol 2024; 124:403-415. [PMID: 38038740 DOI: 10.1007/s00421-023-05350-w] [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: 06/21/2023] [Accepted: 10/20/2023] [Indexed: 12/02/2023]
Abstract
Rinsing the mouth with a carbohydrate (CHO) solution has been shown to enhance exercise performance while reducing neuromuscular fatigue. This effect is thought to be mediated through the stimulation of oral receptors, which activate brain areas associated with reward, motivation, and motor control. Consequently, corticomotor responsiveness is increased, leading to sustained levels of neuromuscular activity prior to fatigue. In the context of endurance performance, the evidence regarding the central involvement of mouth rinse (MR) in performance improvement is not conclusive. Peripheral mechanisms should not be disregarded, particularly considering factors such as low exercise volume, the participant's fasting state, and the frequency of rinsing. These factors may influence central activations. On the other hand, for strength-related activities, changes in motor evoked potential (MEP) and electromyography (EMG) have been observed, indicating increased corticospinal responsiveness and neuromuscular drive during isometric and isokinetic contractions in both fresh and fatigued muscles. However, it is important to note that in many studies, MEP data were not normalised, making it difficult to exclude peripheral contributions. Voluntary activation (VA), another central measure, often exhibits a lack of changes, mainly due to its high variability, particularly in fatigued muscles. Based on the evidence, MR can attenuate neuromuscular fatigue and improve endurance and strength performance via similar underlying mechanisms. However, the evidence supporting central contribution is weak due to the lack of neurophysiological measures, inaccurate data treatment (normalisation), limited generalisation between exercise modes, methodological biases (ignoring peripheral contribution), and high measurement variability.Trial registration: PROSPERO ID: CRD42021261714.
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Affiliation(s)
- Shi Han Tan
- Faculty of Sports and Exercise Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Teng Keen Khong
- Faculty of Sports and Exercise Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Victor S Selvanayagam
- Faculty of Sports and Exercise Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Ashril Yusof
- Faculty of Sports and Exercise Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
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Nuzzo JL, Pinto MD, Nosaka K, Steele J. Maximal Number of Repetitions at Percentages of the One Repetition Maximum: A Meta-Regression and Moderator Analysis of Sex, Age, Training Status, and Exercise. Sports Med 2024; 54:303-321. [PMID: 37792272 PMCID: PMC10933212 DOI: 10.1007/s40279-023-01937-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/10/2023] [Indexed: 10/05/2023]
Abstract
The maximal number of repetitions that can be completed at various percentages of the one repetition maximum (1RM) [REPS ~ %1RM relationship] is foundational knowledge in resistance exercise programming. The current REPS ~ %1RM relationship is based on few studies and has not incorporated uncertainty into estimations or accounted for between-individuals variation. Therefore, we conducted a meta-regression to estimate the mean and between-individuals standard deviation of the number of repetitions that can be completed at various percentages of 1RM. We also explored if the REPS ~ %1RM relationship is moderated by sex, age, training status, and/or exercise. A total of 952 repetitions-to-failure tests, completed by 7289 individuals in 452 groups from 269 studies, were identified. Study groups were predominantly male (66%), healthy (97%), < 59 years of age (92%), and resistance trained (60%). The bench press (42%) and leg press (14%) were the most commonly studied exercises. The REPS ~ %1RM relationship for mean repetitions and standard deviation of repetitions were best described using natural cubic splines and a linear model, respectively, with mean and standard deviation for repetitions decreasing with increasing %1RM. More repetitions were evident in the leg press than bench press across the loading spectrum, thus separate REPS ~ %1RM tables were developed for these two exercises. Analysis of moderators suggested little influences of sex, age, or training status on the REPS ~ %1RM relationship, thus the general main model REPS ~ %1RM table can be applied to all individuals and to all exercises other than the bench press and leg press. More data are needed to develop REPS ~ %1RM tables for other exercises.
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Affiliation(s)
- James L Nuzzo
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia.
| | - Matheus D Pinto
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia
| | - Kazunori Nosaka
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia
| | - James Steele
- School of Sport, Health, and Social Sciences, Solent University, Southampton, UK
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Oliveira-Silva IGR, Dos Santos MPP, da Silva Santos Alves SKL, Lima-Silva AE, de Araujo GG, Ataide-Silva T. Response to letter to the editor: "comment on effect of carbohydrate mouth rinse on muscle strength and muscular endurance: a systematic review with meta-analysis". Crit Rev Food Sci Nutr 2022; 64:1448-1451. [PMID: 36100601 DOI: 10.1080/10408398.2022.2117128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
| | - Maryssa Pontes Pinto Dos Santos
- Laboratory of Applied Sports Science, Institute of Physical Education and Sports, Federal University of Alagoas, Maceió, Brazil
| | | | | | - Gustavo Gomes de Araujo
- Post-Graduate Nutrition Program, Faculty of nutrition, Federal University of Alagoas, Maceió, Brazil
- Laboratory of Applied Sports Science, Institute of Physical Education and Sports, Federal University of Alagoas, Maceió, Brazil
| | - Thays Ataide-Silva
- Post-Graduate Nutrition Program, Faculty of nutrition, Federal University of Alagoas, Maceió, Brazil
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Painelli VDS, Brietzke C, Franco-Alvarenga PE, Canestri R, Vinícius Í, Pires FO. A Narrative Review of Current Concerns and Future Perspectives of the Carbohydrate Mouth Rinse Effects on Exercise Performance. SAGE Open Med 2022; 10:20503121221098120. [PMID: 35615525 PMCID: PMC9125602 DOI: 10.1177/20503121221098120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 04/13/2022] [Indexed: 11/16/2022] Open
Abstract
Previous systematic reviews have confirmed that carbohydrate (CHO) mouth rinse
may boost physical exercise performance, despite some methodological aspects
likely affecting its ergogenic effect. In this review, we discussed if the
exercise mode, pre-exercise fasting status, CHO solutions concentration, CHO
solutions temperature, mouth rinse duration, and CHO placebo effects may
potentially reduce the CHO mouth rinse ergogenic effect, suggesting possible
solutions to manage these potential confounders. The effectiveness of CHO mouth
rinse as a performance booster is apparently related to the origin of the
exercise-induced neuromuscular fatigue, as CHO mouth rinse unequivocally
potentiates endurance rather than sprint and strength exercises performance.
Furthermore, ergogenic effects have been greater in fasting than fed state,
somehow explaining the varied magnitude of the CHO mouth rinse effects in
exercise performance. In this regard, the CHO solution concentration and
temperature, as well as the mouth rinse duration, may have increased the
variability observed in CHO mouth rinse effects in fasting and fed state.
Finally, placebo effects have challenged the potential of the CHO mouth rinse as
an ergogenic aid. Therefore, we suggest that future studies should consider
methodological controls such as sample size and sample homogeneity, proper
familiarization with experimental procedures, and the use of alternative placebo
designs to provide unbiased evidence regarding the potential of the CHO mouth
rinse as an ergogenic aid.
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Affiliation(s)
- Vitor de Salles Painelli
- Exercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil
- Strength Training Study and Research Group, Institute of Health Sciences, Paulista University, São Paulo, Brazil
| | - Cayque Brietzke
- Exercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil
- Human Movement Science and Rehabilitation Program, Federal University of São Paulo, Santos, Brazil
| | - Paulo Estevão Franco-Alvarenga
- Exercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil
- Human Movement Science and Rehabilitation Program, Federal University of São Paulo, Santos, Brazil
| | - Raul Canestri
- Exercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil
| | - Ítalo Vinícius
- Exercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil
| | - Flávio Oliveira Pires
- Exercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil
- Human Movement Science and Rehabilitation Program, Federal University of São Paulo, Santos, Brazil
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Rodrigues Oliveira-Silva IG, Dos Santos MPP, Learsi da Silva Santos Alves SK, Lima-Silva AE, Araujo GGD, Ataide-Silva T. Effect of carbohydrate mouth rinse on muscle strength and muscular endurance: A systematic review with meta-analysis. Crit Rev Food Sci Nutr 2022; 63:8796-8807. [PMID: 35373671 DOI: 10.1080/10408398.2022.2057417] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The present systematic review with meta-analysis summarized studies that investigated the effect of carbohydrate (CHO) mouth rinse on muscle strength and muscular endurance. The search was performed in six databases. Thirteen randomized clinical trials were selected and the standardized mean difference between CHO mouth rinse and placebo for maximal strength and muscular endurance was determined via a random-effects model using Review Manager 5.4 software. Meta-regression was also performed to explore the influence of load, number of sets, number of exercises, fasting time, CHO concentration, and number of mouth rinses on the main outcomes. There was no significant effect of CHO mouth rinse on maximal strength (mean difference= 0.25 kg, 95%CI - 1.81 to 2.32 kg, z = 0.24, p = 0.810). However, there was a significant positive effect of CHO mouth rinse on muscular endurance (mean difference = 1.24 repetitions, 95%CI 0.70 to 1.77 repetitions, z = 4.55, p < 0.001). Meta-regression identified that CHO mouth rinse has greater benefits on muscular endurance when using high workloads, multiple exercises, and a smaller number of mouth rinses (p = 0.001). In conclusion, CHO mouth rinse has no effect on maximal muscle strength but has a positive effect on muscular endurance and seems to optimize when fewer mouth rinses, high workloads and numbers of exercises are used.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2022.2057417.
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Affiliation(s)
| | - Maryssa Pontes Pinto Dos Santos
- Laboratory of Applied Sports Science, Institute of Physical Education and Sports, Federal University of Alagoas, Maceió, Brazil
| | | | | | - Gustavo Gomes de Araujo
- Post-Graduate Nutrition Program, Faculty of Nutrition, Federal University of Alagoas, Maceió, Brazil
- Laboratory of Applied Sports Science, Institute of Physical Education and Sports, Federal University of Alagoas, Maceió, Brazil
| | - Thays Ataide-Silva
- Post-Graduate Nutrition Program, Faculty of Nutrition, Federal University of Alagoas, Maceió, Brazil
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Hartley C, Carr A, Bowe SJ, Bredie WLP, Keast RSJ. Maltodextrin-Based Carbohydrate Oral Rinsing and Exercise Performance: Systematic Review and Meta-Analysis. Sports Med 2022; 52:1833-1862. [PMID: 35239154 PMCID: PMC9325805 DOI: 10.1007/s40279-022-01658-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/01/2022] [Indexed: 12/04/2022]
Abstract
Background Carbohydrates are an important fuel for optimal exercise performance during moderate- and high-intensity exercise; however, carbohydrate ingestion during high-intensity exercise may cause gastrointestinal upset. A carbohydrate oral rinse is an alternative method to improve exercise performance in moderate- to high-intensity exercise with a duration of 30–75 min. This is the first systematic review and meta-analysis to comprehensively examine the isolated effect of maltodextrin-based rinsing on exercise performance. Objective The objective of this review was to establish the effect of a maltodextrin-based carbohydrate oral rinse on exercise performance across various modes of exercise. Furthermore, a secondary objective was to determine the effects of moderators [(1) participant characteristics; (2) oral rinse protocols; (3) exercise protocol (i.e. cycling, running etc.) and (4) fasting] on exercise performance while using a maltodextrin-based, carbohydrate oral rinse. Methods Five databases (MEDLINE, PsycINFO, Embase, SPORTDiscus and Global Health) were systematically searched for articles up to March 2021 and screened using Covidence (a systematic review management tool). A random effects robust meta-analysis and subgroup analyses were performed using Stata Statistical Software: Release 16. Results Thirty-five articles met the inclusion criteria and were included in the systematic review; 34 of these articles were included in the meta-analysis. When using a conventional meta-analytic approach, overall, a carbohydrate oral rinse improved exercise performance in comparison with a placebo (SMD = 0.15, 95% CI 0.04, 0.27; p = 0.01). Furthermore, when implementing an adjusted, conservative, random effects meta-regression model using robust variance estimation, overall, compared with placebo, a carbohydrate oral rinse demonstrated evidence of improving exercise performance with a small effect size (SMD = 0.17, 95% CI − 0.01, 0.34; p = 0.051). Conclusion This systematic review and meta-analysis demonstrates that a maltodextrin-based carbohydrate oral rinse can improve exercise performance. When comparing the two meta-analytic approaches, although non-significant, the more robust, adjusted, random effects meta-regression model demonstrated some evidence of a maltodextrin-based carbohydrate oral rinse improving exercise performance overall. Supplementary Information The online version contains supplementary material available at 10.1007/s40279-022-01658-3.
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Affiliation(s)
- Claudia Hartley
- CASS Food Research Centre, Deakin University, 221 Burwood Highway, Burwood, VIC, 3125, Australia
| | - Amelia Carr
- Centre for Sport Research, Deakin University, 221 Burwood Highway, Burwood, VIC, 3125, Australia
| | - Steven J Bowe
- Deakin Biostatistics Unit, Faculty of Health, Deakin University, 221 Burwood Highway, Burwood, VIC, 3125, Australia
| | - Wender L P Bredie
- Department of Food Science, University of Copenhagen, Rolighedsvej 26, 1958, Frederiksberg, Denmark
| | - Russell S J Keast
- CASS Food Research Centre, Deakin University, 221 Burwood Highway, Burwood, VIC, 3125, Australia.
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Carbohydrate Mouth Rinse Increases High but Not Low Intensity Repetitions to Failure in Resistance-Trained Males. Nutrients 2022; 14:nu14040875. [PMID: 35215525 PMCID: PMC8875644 DOI: 10.3390/nu14040875] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/18/2022] [Accepted: 02/18/2022] [Indexed: 02/01/2023] Open
Abstract
Carbohydrate mouth rinsing (CMR) has been shown to enhance exercise performance. However, the influence of CMR on repetitions to failure with different intensities (40% or 80% of 1 RM) is unknown. Therefore, the purpose of this study was to examine the effects of a 6% CMR solution on muscular endurance assessed at 40% and 80% of 1 RM in resistance-trained males. Sixteen resistance-trained males (age: 25 ± 3 years, height: 182 ± 6 cm, body mass: 86 ± 3 kg, body fat: 16 ± 3%, bench press 1 RM: 106 ± 16 kg, resistance training experience: 5 ± 1 years) completed four conditions in random order. The four conditions consisted of ten seconds of mouth rinsing with 25 mL solutions containing either maltodextrin or placebo (sweetened water) prior to performing a bench press muscular endurance test at either 40% of 1 RM or 80% of 1 RM. Total repetitions, heart rate (HR), ratings of perceived exertion (RPE), glucose (GLU) and felt arousal (FA) were recorded for each condition. There was a significant condition by intensity interaction (p = 0.02). CMR significantly increased total repetitions compared with placebo at the higher intensity (80% of 1 RM; p = 0.04), while there was no effect at the lower intensity (p = 0.20). In addition, HR, RPE, GLU and FA did not differ between conditions or across intensities (p > 0.05). In conclusion, CMR-enhanced muscular endurance performed at higher but not lower intensities.
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Different Doses of Carbohydrate Mouth Rinse Have No Effect on Exercise Performance in Resistance Trained Women. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18073463. [PMID: 33810470 PMCID: PMC8037125 DOI: 10.3390/ijerph18073463] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 03/22/2021] [Accepted: 03/24/2021] [Indexed: 01/19/2023]
Abstract
Carbohydrate (CHO) mouth rinse has been shown to enhance aerobic endurance performance. However, the effects of CHO mouth rinse on muscular strength and endurance are mixed and may be dependent on dosage of CHO. The primary purpose was to examine the effects of different dosages of CHO rinse on strength (bench press 1 repetition maximum [1-RM]) and muscular endurance (40% of 1-RM repetitions to failure) in female athletes. Sixteen resistance-trained females (age: 20 ± 1 years; height: 167 ± 3 cm; body mass: 67 ± 4 kg; BMI: 17 ± 2 kg/m2; resistance training experience: 2 ± 1 years) completed four conditions in random order. The four conditions consisted of a mouth rinse with 25 mL solutions containing either 6% of CHO (Low dose of CHO: LCHO), 12% CHO (Moderate dose of CHO: MCHO), 18% CHO (High dose of CHO: HCHO) or water (Placebo: PLA) for 10 s prior to a bench press strength and muscular endurance test. Maximal strength (1-RM), muscular endurance (reps and total volume), heart rate (HR), ratings of perceived exertion (RPE) and glucose (GLU) were recorded each condition. There were no significant differences in strength (p = 0.95) or muscular endurance (total repetitions: p = 0.06; total volume: p = 0.20) between conditions. Similarly, HR (p = 0.69), RPE (p = 0.09) and GLU (p = 0.92) did not differ between conditions. In conclusion, various doses of CHO mouth rinse (6%, 12% and 18%) have no effect on upper body muscular strength or muscular endurance in female athletes.
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