Carbohydrate Drink Use During 30 Minutes of Variable-Intensity Exercise Has No Effect on Exercise Performance in Premenarchal Girls

2021 ◽  
Vol 33 (2) ◽  
pp. 65-69
Author(s):  
C. Eric Heidorn ◽  
Brandon J. Dykstra ◽  
Cori A. Conner ◽  
Anthony D. Mahon
Keyword(s):  
Peak Power ◽  
Perceived Exertion ◽  
Rating Of Perceived Exertion ◽  
Fatigue Index ◽  
Mean Power ◽  
Variable Intensity ◽  
Performance Effects ◽  
Power Peak ◽  
The Mean ◽  
And Performance

Purpose: This study examined the physiological, perceptual, and performance effects of a 6% carbohydrate (CHO) drink during variable-intensity exercise (VIE) and a postexercise test in premenarchal girls. Methods: A total of 10 girls (10.4 [0.7] y) participated in the study. VO2peak was assessed, and the girls were familiarized with VIE and performance during the first visit. The trial order (CHO and placebo) was randomly assigned for subsequent visits. The drinks were given before VIE bouts and 1-minute performance (9 mL/kg total). Two 15-minute bouts of VIE were completed (10 repeated sequences of 20%, 55%, and 95% power at VO2peak and maximal sprints) before a 1-minute performance sprint. Results: The mean power, peak power, heart rate (HR), %HRpeak, and rating of perceived exertion during VIE did not differ between trials. However, the peak power decreased, and the rating of perceived exertion increased from the first to the second bout. During the 1-minute performance, there were no differences between the trial (CHO vs placebo) for HR (190 [9] vs 189 [9] bpm), %HRpeak (97.0% [3.2%] vs 96.6% [3.0%]), rating of perceived exertion (7.8 [2.3] vs 8.1 [1.9]), peak power (238 [70] vs 235 [60] W), fatigue index (54.7% [10.0%] vs 55.9% [12.8%]), or total work (9.4 [2.6] vs 9.4 [2.1] kJ). Conclusion: CHO supplementation did not alter physiological, perceptual, or performance responses during 30 minutes of VIE or postexercise sprint performance in premenarchal girls.

Effects of a 20-min Nap after Sleep Deprivation on Brain Activity and Soccer Performance

2020 ◽  
Vol 41 (14) ◽  
pp. 1009-1016
Author(s):  
Amornpan Ajjimaporn ◽  
Papatsorn Ramyarangsi ◽  
Vorasith Siripornpanich
Keyword(s):  
Sleep Deprivation ◽  
Perceived Exertion ◽  
Brain Activity ◽  
Rating Of Perceived Exertion ◽  
Soccer Players ◽  
Mean Power ◽  
Auditory Reaction Time ◽  
Normal Sleep ◽  
The Mean ◽  
Leg Muscle

AbstractWe examined effects of a 20-min nap following 3 h of sleep deprivation on brain wave activity, auditory reaction time, the running-based anaerobic sprint test, leg muscle strength and the rating of perceived exertion in male college soccer players. Eleven players underwent three sleep conditions; normal sleep, sleep deprivation and 20-min nap after sleep deprivation. The sleep deprivation demonstrated an increase in the mean power of delta waves over the frontal area and a decrease in the mean power of alpha waves over the parietal area compared to the normal sleep. The nap and the sleep deprivation showed an increase in auditory reaction time compared with those in the normal sleep. The sleep deprivation demonstrated a decrease in the running-based anaerobic sprint test compared to the normal sleep, whereas the nap has partially reversed only minimal power and average power of the running-based anaerobic sprint test. The nap showed a recovery effect on leg muscle strength, but not on the rating of perceived exertion compared with the sleep deprivation. Thus, a 20-min nap after sleep deprivation did not completely return brain activity back to active state and did not entirely reverse the negative impact of sleep deprivation on soccer performance in soccer players.

scholarly journals Warm-up durations in a hot-dry climate affect thermoregulation, mean power-output and fatigue, but not peak power in specific soccer repeated-sprint ability

2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Mohamed Frikha ◽  
Nesrine Chaâri ◽  
Noureddine Ben Said ◽  
Mohammed Shaab Alibrahim
Keyword(s):  
Power Output ◽  
Peak Power ◽  
Perceived Exertion ◽  
Rating Of Perceived Exertion ◽  
Tympanic Temperature ◽  
Muscular Power ◽  
Mean Power ◽  
Warm Up ◽  
Repeated Sprint ◽  
Mean Power Output

Abstract Background This study addressed the lack of data on the effect of warm-up (WU) duration in hot-dry climate (~ 30 °C; ~ 18% RH), on thermoregulation, muscular power-output, and fatigue after specific soccer repeated-sprint test (RSA). Methods Eleven amateur soccer players participated in a cross-over randomized study and they underwent the Bangsbo repeated-sprint test, after three WU durations (i.e. WU10, WU15 and WU20 min) at 70% of MAV, and on different days. Peak power (PP), mean power (MP) and the fatigue index (FI) were recorded and analyzed. Likewise, heart rate (HR), tympanic temperature (Ttym), mean body temperature (MBT) and rating of perceived exertion (RPE) were recorded during each session. Results The repeated measure ANOVA showed that MP improved after WU15 in comparison to WU10 and WU20 (p = 0.04 and p = 0.001; respectively). Nonetheless, no significant effect on PP was recorded after all WU durations. FI during RSA increased after WU20 in comparison to WU15 and WU10 (p < 0.001 and p = 0.003; respectively). Higher RPE values (p < 0.001) were recorded after WU15 and WU20 in comparison to WU10 duration. The two-way ANOVA showed higher ΔTtym and ΔMBT values after WU15 and WU20 compared to WU10 (p = 0.039 and p < 0.001for Ttym; p = 0.005 and p < 0.001 for MBT, respectively). Conclusions The WU15 at 70% of MAV better assists mean power-output during soccer RSA in hot-dry (~ 30 °C; 18% RH) climate, but not peak power. Reducing WU duration up to 10 min seems to be insufficient to induce beneficial physiological changes necessary for optimizing repeated-sprint performance, while its extension up to 20 min remains detrimental for muscular power and induces higher fatigue.

Physiological, Psychometric, and Performance Effects of the Christmas Break in Australian Football

2015 ◽  
Vol 10 (1) ◽  
pp. 120-123 ◽  
Author(s):  
Martin Buchheit ◽  
Will Morgan ◽  
Jarryd Wallace ◽  
Matthew Bode ◽  
Nick Poulos
Keyword(s):  
High Intensity ◽  
Perceived Exertion ◽  
Training Session ◽  
Peak Force ◽  
Fat Free Mass ◽  
Rating Of Perceived Exertion ◽  
Running Activity ◽  
Performance Effects ◽  
Australian Football ◽  
And Performance

Purpose:The aim of the current study was to quantify the physiological, psychometric, and performance effects of a 2-wk Christmas break in a professional Australian Football League club.Methods:A series of physiological (eg, heart-rate [HR] response to a 5-min submaximal run and skinfold thicknesses), psychometric (rating-of-perceived-exertion [RPE] responses and wellness variables), and performance (running activity during standardized handball games, isometric midthigh pull [IMTP] peak force, and countermovement jump [CMJ]) measures were conducted in the weeks before and after the break.Results:There was a possible and small increase in the sum of 7 skinfolds, while body mass and fat-free mass remained possible and likely unchanged, respectively. Sleep and stress scores remained likely to almost certainly unchanged, but there were some small, possible to likely decreases in fatigue and soreness scores. HR and RPE responses to the 5-min submaximal run were likely slightly lower (ie, improved) after the break. High-intensity running and acceleration distance during a standard handball game were very likely slightly greater, while HR and RPE responses to the game were possibly to very likely unchanged. HR responses to a high-intensity training session remained very likely unchanged. There was also a likely small increase in IMTP peak force but likely to very likely no change in CMJ variables.Conclusions:The results show that players returned from a 2-wk break during preseason well recovered, with preserved to improved levels of strength and cardiorespiratory fitness, despite small increases in skinfold thickness.

Exercise Prescription Using the Borg Rating of Perceived Exertion to Improve Fitness

2017 ◽  
Vol 39 (02) ◽  
pp. 115-123 ◽  
Author(s):  
Manuel Garnacho-Castaño ◽  
Raúl Domínguez ◽  
Arturo Muñoz González ◽  
Raquel Feliu-Ruano ◽  
Noemí Serra-Payá ◽  
...  
Keyword(s):  
Heart Rate ◽  
Peak Power ◽  
Perceived Exertion ◽  
Exercise Prescription ◽  
Time Effect ◽  
Rating Of Perceived Exertion ◽  
Muscular Fitness ◽  
Time Interaction ◽  
Circuit Resistance Training ◽  
Circuit Resistance

AbstractThe present study aimed to compare two fitness-training methodologies, instability circuit resistance training (ICRT) versus traditional circuit resistance training (TCRT), applying an experimental model of exercise prescription controlling and modulating exercise load using the Borg rating of perceived exertion. Forty-four healthy young adults age (21.6±2.3 years) were randomly assigned to three groups: TCRT (n=14), ICRT (n=14) and a control group (n=16). Strength and cardiorespiratory tests were chosen to evaluate cardiorespiratory and muscular fitness before and after the training program. In cardiorespiratory data, a significant difference was observed for the time effect in VO2max, peak heart rate, peak velocity, and heart rate at anaerobic threshold intensity (p<0.05) in the experimental groups. In strength variables, a significant Group x Time interaction effect was detected in 1RM, in mean propulsive power, and in peak power (p≤0.01) in the back squat exercise. In the bench press exercise, a significant time effect was detected in 1RM, in mean propulsive power, and in peak power, and a Group x Time interaction in peak power (all p<0.05). We can conclude that applying an experimental model of exercise prescription using RPE improved cardiorespiratory and muscular fitness in healthy young adults in both experimental groups.

Physiological Demands of Basic Fire Management Tasks in Members of the Canadian Armed Forces: A Pilot Study

2021 ◽  
Author(s):  
Étienne Chassé ◽  
Daniel Théoret ◽  
Martin P Poirier ◽  
François Lalonde
Keyword(s):  
Heart Rate ◽  
Perceived Exertion ◽  
Fire Management ◽  
Armed Forces ◽  
Rating Of Perceived Exertion ◽  
Minimum Standard ◽  
Canadian Armed Forces ◽  
The Mean ◽  
Physiological Demands ◽  
Task Simulation

ABSTRACT Introduction Members of the Canadian Armed Forces (CAF) are required to meet the minimum standards of the Fitness for Operational Requirements of CAF Employment (FORCE) job-based simulation test (JBST) and must possess the capacity to perform other common essential tasks. One of those tasks is to perform basic fire management tasks during fire emergencies to mitigate damage and reduce the risk of injuries and/or death until professional firefighters arrive at the scene. To date however, the physiological demands of common firefighting tasks have mostly been performed on professional firefighters, thus rendering the transferability of the demands to the general military population unclear. This pilot study aimed to quantify, for the first time, the physiological demands of basic fire management tasks in the military, to determine if they are reflected in the FORCE JBST minimum standard. We hypothesized that the physiological demands of basic fire management tasks within the CAF are below the physiological demands of the FORCE JBST minimum standard, and as such, be lower than the demands of professional firefighting. Materials and methods To achieve this, 21 CAF members (8 females; 13 males; mean [SD] age: 33 [10] years; height: 174.5 [10.5] cm; weight: 85.4 [22.1] kg, estimated maximal oxygen uptake [$\dot V$O2peak]: 44.4 (7.4) mL kg−1 min−1) participated in a realistic, but physically demanding, JBST developed by CAF professional firefighting subject matter experts. The actions included lifting, carrying, and manipulating a 13-kg powder fire extinguisher and connecting, coupling, and dragging a 38-mm fire hose over 30 m. The rate of oxygen uptake ($\dot V$O2), heart rate, and percentage of heart rate reserve were measured continuously during two task simulation trials, which were interspersed by a recovery period. Rating of perceived exertion (6-no exertion; 20-maximal exertion) was measured upon completion of both task simulations. Peak $\dot V$O2 ($\dot V$O2peak) was estimated based on the results of the FORCE JBST. Results The mean (SD) duration of both task simulation trials was 3:39 (0:19) min:s, whereas the rest period in between both trials was 62 (19) minutes. The mean O2 was 21.1 (4.7) mL kg−1 min−1 across trials, which represented 52.1 (12.2) %$\dot V$O2peak and ∼81% of the FORCE JBST. This was paralleled by a mean heart rate of 136 (18) beats min−1, mean percentage of heart rate reserve of 61.2 (10.8), and mean rating of perceived exertion of 11 ± 2. Other physical components of the JBST consisted of lifting, carrying, and manipulating a 13-kg load for ∼59 seconds, which represents 65% of the load of the FORCE JBST. The external resistance of the fire hose drag portion increased up to 316 N, translating to a total of 6205 N over 30 m, which represents 96% of the drag force measured during the FORCE JBST. Conclusions Our findings demonstrate that the physiological demands of basic fire management tasks in the CAF are of moderate intensity, which are reflected in the CAF physical fitness standard. As such, CAF members who achieve the minimum standard on the FORCE JBST are deemed capable of physically performing basic fire management tasks during fire emergencies.

scholarly journals Does Post-Activation Potentiation Protocols affect Anaerobic Performance in women Taolu Wushu Athletes?

2021 ◽  
Author(s):  
José Afonso ◽  
Hengameh Moradian ◽  
Rasoul Eslami ◽  
Alexandre Martins ◽  
Abdolhossein Parnow
Keyword(s):  
Peak Power ◽  
Performance Enhancement ◽  
Anaerobic Performance ◽  
Fatigue Index ◽  
Short Term ◽  
Mean Power ◽  
Significant Difference ◽  
Strength Based ◽  
Rest Time ◽  
Lactate Levels

Abstract Introduction: Post-activation potentiation has an influence on short duration and high intensity function. This study aimed to answer this question whether post-activation potentiation protocol in different models has effect on anaerobic performance in women Wushu athletes. Methods: Women elite Taolu Wushu athletes participated in current crossover design study. (i) specific Wushu WU (Wushu WU); (ii) Strength-based WU (StreWU); and (iii) Speed-based WU (SpeWU) were performed by Wushu athletes in three inconsecutive days separated by 48 h. Five minutes after each WU protocols, Running-Based Anaerobic Sprint Test (RAST) was performed. Heart rate, immediately, and blood lactate were measured for 4 times: before WU protocols, immediately after WU protocols, before RAST, immediately after RAST.Results: Data analysis revealed significant differences in 4 time points of lactate levels (p=0.001; d=1.71), although no significant difference among protocols was observed. Values of variables obtained from RAST showed that StreWU had a significant impact on minimum power (p<0.05; d=-0.795) comparing to WushuWU and on fatigue index comparing to SpeWU (p<0.05; d=-0.799). No significant differences were found among the WU protocols for peak power and mean power.Conclusion: All WU protocols had mostly the same effect, and PAP was not very effective. Possibly, the WU protocols generated too much fatigue, due to the short-term rest time. However, longer intervals would likely enter the realm of post-activation performance enhancement, which is distinct from PAP.

Increased Cardiorespiratory Stress During Submaximal Cycling After Ketone Monoester Ingestion in Endurance-Trained Adults

2021 ◽  
Author(s):  
Devin Goddard McCarthy ◽  
William Bostad ◽  
Fiona Jane Powley ◽  
Jonathan P. Little ◽  
Douglas Richards ◽  
...  
Keyword(s):  
Body Mass ◽  
Ketone Body ◽  
Perceived Exertion ◽  
Bolus Dose ◽  
Ventilatory Threshold ◽  
Time Trial ◽  
Rating Of Perceived Exertion ◽  
Threshold Intensity ◽  
Double Blind ◽  
And Performance

There is growing interest in the effect of exogenous ketone body supplementation on exercise responses and performance. The limited studies to date have yielded equivocal data, likely due in part to differences in dosing strategy, increase in blood ketones, and participant training status. Using a randomized, double-blind, counterbalanced design, we examined the effect of ingesting a ketone monoester (KE) supplement (600 mg/kg body mass) or flavour-matched placebo in endurance-trained adults (n=10 males, n=9 females; VO2peak=57±8 ml/kg/min). Participants performed a 30-min cycling bout at ventilatory threshold intensity (71±3% VO2peak), followed 15 min later by a 3 kJ/kg body mass time-trial. KE versus placebo ingestion increased plasma [β-hydroxybutyrate] before exercise (3.9±1.0 vs 0.2±0.3 mM, p<0.0001, dz=3.4), ventilation (77±17 vs 71±15 L/min, p<0.0001, dz=1.3) and heart rate (155±11 vs 150±11 beats/min, p<0.001, dz=1.2) during exercise, and rating of perceived exertion at the end of exercise (15.4±1.6 vs 14.5±1.2, p<0.01, dz=0.85). Plasma [β-hydroxybutyrate] remained higher after KE vs placebo ingestion before the time-trial (3.5±1.0 vs 0.3±0.2 mM, p<0.0001, dz=3.1), but performance was not different (KE: 16:25±2:50 vs placebo: 16:06±2:40 min:s, p=0.20; dz=0.31). We conclude that acute ingestion of a relatively large KE bolus dose increased markers of cardiorespiratory stress during submaximal exercise in endurance-trained participants. Novelty bullets: •Limited studies have yielded equivocal data regarding exercise responses after acute ketone body supplementation. •Using a randomized, double-blind, placebo-controlled, counterbalanced design, we found that ingestion of a large bolus dose of a commercial ketone monoester supplement increased markers of cardiorespiratory stress during cycling at ventilatory threshold intensity in endurance-trained adults.

Time Spent Near V˙O2max During Different Cycling Self-Paced Interval Training Protocols

2020 ◽  
pp. 1-7
Author(s):  
Cristiano Dall’ Agnol ◽  
Tiago Turnes ◽  
Ricardo Dantas De Lucas
Keyword(s):  
Power Output ◽  
Perceived Exertion ◽  
Recovery Period ◽  
Interval Training ◽  
Exercise Duration ◽  
Rating Of Perceived Exertion ◽  
Recovery Ratio ◽  
Active Recovery ◽  
Mean Power ◽  
Work Recovery

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 .

scholarly journals Training Loads, Wellness And Performance Before and During Tapering for a Water-Polo Tournament

2019 ◽  
Vol 66 (1) ◽  
pp. 131-141
Author(s):  
Petros G. Botonis ◽  
Argyris G. Toubekis ◽  
Theodoros I. Platanou
Keyword(s):  
Muscle Soreness ◽  
Perceived Exertion ◽  
Swimming Performance ◽  
Training Load ◽  
Rating Of Perceived Exertion ◽  
Training Period ◽  
Training Strategy ◽  
Water Polo ◽  
And Performance ◽  
High Level

AbstractWe investigated the effectiveness of a short-duration training period including an overloaded (weeks 1 and 2) and a reduced training load period (weeks 3 and 4) on wellness, swimming performance and a perceived internal training load in eight high-level water-polo players preparing for play-offs. The internal training load was estimated daily using the rating of perceived exertion (RPE) and session duration (session-RPE). Perceived ratings of wellness (fatigue, muscle soreness, sleep quality, stress level and mood) were assessed daily. Swimming performance was evaluated through 400-m and 20-m tests performed before (baseline) and after the end of weeks 2 and 4. In weeks 3 and 4, the internal training load was reduced by 19.0 ± 3.8 and 36.0 ± 4.7%, respectively, compared to week 1 (p = 0.00). Wellness was improved in week 4 (20.4 ± 2.8 AU) compared to week 1 and week 2 by 16.0 ± 2.2 and 17.3 ± 2.9 AU, respectively (p =0.001). At the end of week 4, swimming performance at 400-m and 20-m tests (299.0 ± 10.2 and 10.2 ± 0.3 s) was improved compared to baseline values (301.4 ± 10.9 and 10.4 ± 0.4 s, p < 0.05) and the overloading training period (week 2; 302.9 ± 9.0 and 10.4 ± 0.4 s, p < 0.05). High correlations were observed between the percentage reduction of the internal training load from week 4 to week 1 (-25.3 ± 5.5%) and the respective changes in 20-m time (-2.1 ± 2.2%, r = 0.88, p < 0.01), fatigue perception (39.6 ± 27.1%), muscle soreness (32.5 ± 26.6%), stress levels (25.6 ± 15.1%) and the overall wellness scores (28.6 ± 21.9%, r = 0.74-0.79, p < 0.05). The reduction of the internal training load improved the overall perceived wellness and swimming performance of players. The aforementioned periodization approach may be an effective training strategy in the lead-up to play-off tournaments.

scholarly journals Differences in the Effects of Carbohydrate Food Form on Endurance Performance to Exhaustion

1993 ◽  
Vol 3 (1) ◽  
pp. 41-54 ◽  
Author(s):  
Scott D. Murdoch ◽  
Terry L. Bazzarre ◽  
Ian P. Snider ◽  
Allan H. Goldfarb
Keyword(s):  
Glucose Concentration ◽  
Blood Glucose Concentration ◽  
Endurance Performance ◽  
Performance Effects ◽  
Endurance Tests ◽  
The Mean ◽  
And Performance ◽  
Mean Blood Glucose ◽  
Mean Glucose ◽  
Placebo Drink

This investigation examined the metabolic and performance effects of ingesting solid compared to slurried carbohydrate food (bananas) between two prolonged exhaustive exercise bouts. Eight highly trained bale triathletes performed four exhaustive endurance tests (ET), each separated by at least 2 weeks. Each ET consisted of a 90-min run followed by 90 min of cycling, both at 70%. Workloads were then gradually increased on the cycle, and subjects continued to cycle until exhausted. They then rested for 20 min and ingested one of the following: an artificially sweetened placebo drink (P), slurried bananas (SL), or solid bananas (SO). Bananas were given in equal portions relative to each subject's body weight. Subjects cycled to exhaustion a second time at 70% of their, at which point the mean blood glucose concentration for the combined carbohydrate treatments was significantly higher than that from the P treatment. The mean glucose concentration from the SL treatment did not differ significantly from the SO treatment. These data demonstrate that solid bananas are as effective as slurried bananas in maintaining plasma glucose and in enhancing endurance exercise performance.

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