The Effect of Protein Supplementation on Lactate Accumulation during Submaximal and Maximal Exercise

1992 ◽  
Vol 2 (4) ◽  
pp. 307-316 ◽  
Author(s):  
Matthew D. Vukovich ◽  
Rick L. Sharp ◽  
Douglas S. King ◽  
Kellie Kershishnik

Eleven subjects performed a graded exercise test after 1 week of protein supplementation (PRO) or glucose polymer placebo (CON), randomly assigned in a double blind fashion. The exercise consisted of 3-min graded exercise bouts separated by 10 min of active recovery at zero pedal resistance. Subjects then performed a 30-sec Wingate test (WIN) to assess performance during supramaximal exercise. Blood samples were obtained in the last 15 sec of each exercise and recovery period. PRO resulted in a decrease in blood lactate following 120%and WIN, an increase in blood alanine at all time points, and lower postexercise muscle lactate and glycogen. Resting muscle GPT activity was 47% higher during the PRO trial. Mean power output during the WIN did not differ between PRO and CON. The WIN fatigue index was not significantly different between PRO and CON. The increased alanine may reflect increased transamination of pyruvate, thereby reducing the accumulation of lactate, which in turn had a marginal effect on performance during supramaximal exercise.

2021 ◽  
Vol 6 (3) ◽  
pp. 64
Author(s):  
Corinne E. Meglic ◽  
Caroline M. Orman ◽  
Rebecca R. Rogers ◽  
Tyler D. Williams ◽  
Christopher G. Ballmann

The purpose of this study was to investigate the effects of listening to preferred versus non-preferred warm-up music on anaerobic sprint performance in Division I NCAA female athletes. Female collegiate athletes (n = 14) were recruited for this study. In a counterbalanced, crossover study design, participants completed two separate visits, each with a different warm-up music condition: preferred (Pref) or non-preferred (Non-pref). During each visit, participants completed a 3 min standardized cycling warm-up at 50 Watts while listening to Pref or Non-pref music. Following this, participants completed 3 × 15 s Wingate Anaerobic Tests (WAnTs) with a 2 min active recovery period in between tests. Motivation to exercise was measured immediately following the warm-up (WU), WAnT1, WAnT2, and WAnT3. The rate of perceived exertion (RPE) was also measured after each WAnT. Each visit was separated by a minimal recovery period of 48 h. Mean power, total work, RPE, and motivation were analyzed. Mean power (p = 0.044; d = 0.91) and total work (p = 0.045; d = 0.78) were significantly higher during the Pref music condition versus Non-pref. RPE remained unchanged regardless of condition (p = 0.536; d = 0.01). Motivation was significantly higher with Pref warm-up music compared to Non-pref (p < 0.001; d = 1.55). These results show that listening to Pref warm-up music has an ergogenic benefit during repeated sprints in comparison to Non-pref music and improves motivation to exercise. Listening to warm-up music prior to high-intensity repeated exercise may aid in optimizing performance and training in collegiate athletes.


Author(s):  
Cristiano Dall’ Agnol ◽  
Tiago Turnes ◽  
Ricardo Dantas De Lucas

Purpose: Cyclists may increase exercise intensity by prolonging exercise duration and/or shortening the recovery period during self-paced interval training, which could impact the time spent near . Thus, the main objective of this study was to compare the time spent near during 4 different self-paced interval training sessions. Methods: After an incremental test, 11 cyclists (mean [SD]: age = 34.4 [6.2] y; ) performed in a randomized order 4 self-paced interval training sessions characterized by a work–recovery ratio of 4:1 or 2:1. Sessions comprised 4 repetitions of 4 minutes of cycling with 1 minute (4/1) or 2 minutes (4/2) of active recovery or 8 minutes of cycling with 2 minutes (8/2) or 4 minutes (8/4) of active recovery. Time spent at 90% to 94% (), ≥95% (), and 90% to 100% () was analyzed in absolute terms and relative to the total work duration. Power output, heart rate, blood lactate, and rating of perceived exertion were compared. Results: The 8/4 session provided higher absolute and than 8/2 (P = .015 and .029) and 4/1 (P = .002 and .047). The 4/2 protocol elicited higher relative (47.7% [26.9%]) and (23.5% [22.7%]) than 4/1 (P = .015 and .028) and 8/2 (P < .01). Session 4/2 (275 [23] W) elicited greater mean power output (P < .01) than 4/1 (261 [27] W), 8/4 (250 [25] W), and 8/2 (234 [23] W). Conclusions: Self-paced interval training composed of 4-minute and 8-minute work periods efficiently elicit , but protocols with a work–recovery ratio of 2:1 (ie, 4/2 and 8/4) could be prioritized to maximize .


Author(s):  
Vicente Ávila-Gandía ◽  
Antonio Torregrosa-García ◽  
Antonio J. Luque-Rubia ◽  
María Salud Abellán-Ruiz ◽  
Desirée Victoria-Montesinos ◽  
...  

Abstract Background Fish oils were studied as ergogenic aids in a number of mixed physical trial designs showing promising results. However, the heterogeneous purity of the studied supplements, combined with the variety of physical tests employed call for more studies to confirm these findings, ideally with standardised supplements. Our aim was to test a supplement highly concentrated in DHA (DHA:EPA ratio equal to approximately 8:1) on a maximal cycling test to elucidate performance improvements mainly due to DHA. Methods A double-blind, placebo controlled, randomised balanced, parallel design, in competitive amateur cyclists was employed. They were all male, older than 18 years old, with training routine of 2 to 4 sessions per week lasting at least one hour each. A ramp cycling test to exhaustion with a subsequent 5 min recovery phase was employed before and after treatment to analyse aerobic metabolism and lactate clearance after the bout. After 30 days of supplementation with 975 mg of re-esterified DHA, the thirty-eight cyclist who completed the study were finally included for statistical analysis. Results Mean power output at ventilatory threshold 2 (VT2) improved after DHA supplementation both as absolute (△DHA versus △PLA: 6.33–26.54 Watts; CI 95%) and relative (p=0.006) values, paralleled with higher oxygen consumption at VT2 both for absolute (DHA 2729.4 ±304.5, 3045.9 ±335.0; PLA 2792.3 ±339.5, 2845.5 ±357.1; ml·min−1 baseline versus post p=0.025) and relative values (DHA 36.6 ±5.0, 41.2 ±5.4; PLA 37.2 ±5.7, 38.1 ±5.2; ml·kg−1·min−1 baseline versus post p=0.024). Heart rate recovery rate improved during the recovery phase in the DHA group compared to PLA (p=0.005). Conclusion DHA is capable of improving mean power output at the ventilatory threshold 2 (anaerobic ventilatory threshold) in amateur competitive cyclists. It is unclear if these findings are the result of the specific DHA supplement blend or another factor.


Author(s):  
Kristin E. MacLeod ◽  
Sean F. Nugent ◽  
Susan I. Barr ◽  
Michael S. Koehle ◽  
Benjamin C. Sporer ◽  
...  

Beetroot juice (BR) has been shown to lower the oxygen cost of exercise in normoxia and may have similar effects in hypoxia. We investigated the effect of BR on steady-state exercise economy and 10-km time trial (TT) performance in normoxia and moderate hypoxia (simulated altitude: ~2500 m). Eleven trained male cyclists (VO2peak ≥ 60 ml·kg-1·min-1) completed four exercise trials. Two hours before exercise, subjects consumed 70 mL BR (~6 mmol nitrate) or placebo (nitrate-depleted BR) in a randomized, double-blind manner. Subjects then completed a 15-min self-selected cycling warm-up, a 15-min steady-state exercise bout at 50% maximum power output, and a 10-km time trial (TT) in either normoxia or hypoxia. Environmental conditions were randomized and single-blind. BR supplementation increased plasma nitrate concentration and fraction of exhaled nitric oxide relative to PL (p < .05 for both comparisons). Economy at 50% power output was similar in hypoxic and normoxic conditions (p > .05), but mean power output was greater in the normoxic TT relative to the hypoxic TT (p < .05). BR did not affect economy, steady-state SpO2, mean power output, or 10-km TT completion time relative to placebo in either normoxia or hypoxia (p > .05 in all comparisons). In conclusion, BR did not lower the oxygen cost of steady-state exercise or improve exercise performance in normoxia or hypoxia in a small sample of well-trained male cyclists.


1989 ◽  
Vol 67 (6) ◽  
pp. 2376-2382 ◽  
Author(s):  
M. E. Nevill ◽  
L. H. Boobis ◽  
S. Brooks ◽  
C. Williams

Sixteen subjects volunteered for the study and were divided into a control (4 males and 4 females) and experimental group (4 males and 4 females, who undertook 8 wk of sprint training). All subjects completed a maximal 30-s sprint on a nonmotorized treadmill and a 2-min run on a motorized treadmill at a speed designed to elicit 110% of maximum oxygen uptake (110% run) before and after the period of training. Muscle biopsies were taken from vastus lateralis at rest and immediately after exercise. The metabolic responses to the 110% run were unchanged over the 8-wk period. However, sprint training resulted in a 12% (P less than 0.05) and 6% (NS) improvement in peak and mean power output, respectively, during the 30-s sprint test. This improvement in sprint performance was accompanied by an increase in the postexercise muscle lactate (86.0 +/- 26.4 vs. 103.6 +/- 24.6 mmol/kg dry wt, P less than 0.05) and plasma norepinephrine concentrations (10.4 +/- 5.4 vs. 12.1 +/- 5.3 nmol/l, P less than 0.05) and by a decrease in the postexercise blood pH (7.17 +/- 0.11 vs. 7.09 +/- 0.11, P less than 0.05). There was, however, no change in skeletal muscle buffering capacity as measured by the homogenate technique (67.6 +/- 6.5 vs. 71.2 +/- 4.5 Slykes, NS).


2020 ◽  
Vol 15 (11) ◽  
pp. 1934578X2096959
Author(s):  
Yoshio Suzuki ◽  
Kotaro Sato ◽  
Norie Arai ◽  
Shin Endo

Trehalose is a disaccharide consisting of 2 glucose units linked in an alpha 1,1-glycosidic bond. Pre-exercise trehalose ingestion enhances exercise performance within 30 minutes. Enhanced performance was hypothesized to be due to a mouth rinse effect. A 3-arm double-blind crossover trial was conducted to test this hypothesis. Ten healthy male collegiate distance runners rinsed their mouths with either trehalose (6% w/v) or maltose (6% w/v) or acesulfame potassium (0.04 mg/mL) for 5 seconds and then performed an exercise assessment composed of 6-second peak power and endurance tests. Trehalose induced the highest mean power output ( P < .01) in peak power tests. In the endurance test, trehalose consistently showed higher mean power output than maltose. The 3 test drinks displayed indistinguishable sweetness and were expected to activate receptors for sweetness (T1R2-T1R3) with the same intensity. Trehalose activates taste receptors T1R1-T1R3, T1R3-T1R3 homodimer, and T1R2-T1R3, whereas sucrose activates only T1R2-T1R3. Therefore, a difference in mouth rinse effect might be due to a specific receptor in the oral cavity that recognizes differences between trehalose and maltose.


2018 ◽  
Vol 7 (1) ◽  
pp. 48-55
Author(s):  
Karim - Azali Alamdari ◽  
Jabbar Bashiri

The effects of each hypoxemic exercise session or overall training period still remains to be more elucidated in elite athletes. Therefore, we investigated the effects of hypobaric endurance training on lymphocytes mobilization and senescence and also their surface Thiol levels following to graded exercise test (GXT) in elite male athletes. Fourty six volunteer subjects were randomized into normobaric control (NC), hypobaric control (HC), normobaric exercise (NE) and hypobaric exercise (HE) groups. The NE and HE groups were exposed to homeland (700 mmHg) and 2800 meters above sea level (570 mmHg) simulated barometric pressures respectively, while HC and NC groups were remained sedentary at the same conditions. The training was included on treadmill running for four weeks, five sessions/week, 45 min/ session. Each session was consisted of three-min warmed up period, three cycles of 10-min running at 65% maximal heart rate reserve (HRRmax) interspersed with a three-min active recovery and three-min cool-down running period. Two GXTs were performed before (baseline) and after the interventions and blood samples were collected three times at both occasions. In all groups, mobilization of CD8+lymphocytes and senescent phenotype population of their both CD4+ and CD8+ subsets were increased after both GXTs, however; these changes were reversed following to recovery period(P<0.05). Moreover, HE were decreased lymphocytes surface thiol levels before and after the second GXT (P<0.05).it can be concluded that HE has no additional benefits for elite athletes regarded to lymphocytes mobilization and senescence, however; it may render them to oxidative stress.  


2014 ◽  
Vol 9 (5) ◽  
pp. 845-850 ◽  
Author(s):  
Kristy Martin ◽  
Disa Smee ◽  
Kevin G. Thompson ◽  
Ben Rattray

Purpose:Nitrate supplementation improves endurance exercise and single bouts of high-intensity activity, but its effect on repeated sprints is unclear. This study is the first to investigate the effects of acute dietary nitrate supplementation during a high-intensity intermittent-sprint test to exhaustion.Methods:Team-sport athletes (9 male, age 22.3 ± 2.1 y, VO2max 57.4 ± 8.5 mL · kg−1 · min−1; 7 female, age 20.7 ± 1.3 y, VO2max 47.2 ± 8.5 mL · kg−1 · min−1) were assigned to a double-blind, randomized, crossover design. Participants consumed 70 mL of concentrated beetroot juice containing a minimum of 0.3 g of nitrate (NT) or 70 mL of placebo (PL) 2 h before a repeated-sprint protocol involving repeated 8-s sprints with 30-s recovery on a cycle ergometer to exhaustion.Results:Fewer sprints (NT = 13 ± 5 vs PL = 15 ± 6, P = .005, d = 0.41) and less total work (NT = 49.2 ± 24.2 kJ vs PL = 57.8 ± 34.0 kJ, P = .027, d = 0.3) were completed in NT relative to PL. However there was no difference in overall mean power output or the mean power output for each individual 8-s sprint.Conclusions:These findings suggest that dietary nitrate is not beneficial for improving repeated-sprint performance, at least when such sprints are near-maximal and frequent in nature. The lack of an effect of nitrate at near-maximal oxygen uptake supports the suggestion that at greater exercise intensities nitrate does not have an ergogenic effect.


2019 ◽  
Vol 40 (11) ◽  
pp. 711-716 ◽  
Author(s):  
Sebastiaan Dalle ◽  
Stefan De Smet ◽  
Willem Geuns ◽  
Bart Van Rompaye ◽  
Peter Hespel ◽  
...  

AbstractThe purpose of this study was to evaluate whether NaHCO3, administered via a 9-h stacked loading protocol (i.e. repeated supplementation with small doses in order to obtain a gradual increase in blood [HCO3 -]), has an ergogenic effect on repeated all-out exercise. Twelve physically active males were randomly assigned to receive either NaHCO3 (BIC) or placebo (PL) in a double-blind cross-over design. NaHCO3 supplementation was divided in three identical 3-h cycles: a 6.3 g bolus at the start, followed by 2.1 g doses at +1-h and +2-h, yielding a total NaHCO3 intake of 0.4 g·kg−1 BM over 9-h. At the end of each cycle, participants performed 2-min all-out cycling. Capillary blood samples were analyzed for [HCO3 -], pH and [La-]. Pre-exercise blood [HCO3 -] in PL decreased from 25.6±0.2 mmol·L−1 in bout 1 to 23.6±0.2 mmol·L−1 in bout 4, while increasing from 25.5±0.2 to 31.2±0.4 mmol·L−1 in BIC (P<0.05). Concomitantly, pre-exercise pH values gradually decreased in PL (from 7.41±0.00 to 7.39±0.01) and increased in BIC (from 7.41±0.01 to 7.47±0.01; P<0.05). Mean power output of the four bouts was higher in BIC (428±20 W) than in PL (420±20 W; P<0.05). The ergogenic effect on repeated all-out exercise occurred in the absence of gastrointestinal distress.


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