scholarly journals Carbohydrate–protein ingestion improves subsequent running capacity towards the end of a football-specific intermittent exercise

2011 ◽  
Vol 36 (5) ◽  
pp. 748-757 ◽  
Author(s):  
Abdullah F. Alghannam
Keyword(s):  
Perceived Exertion ◽  
Intermittent Exercise ◽  
Peak Oxygen Consumption ◽  
Football Players ◽  
Endurance Capacity ◽  
Half Time ◽  
Ratings Of Perceived Exertion ◽  
Football Match ◽  
Protein Ingestion ◽  
Intermittent Activity

The majority of football players succumb to fatigue towards the end of the game. This study was designed to examine the influence of protein coingestion with carbohydrate (CHO) vs. an isocaloric CHO supplement on subsequent running capacity towards the end of a simulated football match. Six male amateur football players participated in 3 trials applied in a randomized cross-over experimental design. A laboratory-based, football-specific intermittent exercise was allocated for 75 min interspersed with a 15-min recovery, immediately followed by run time to fatigue (RTF) at 80% peak oxygen consumption. In each trial, prior to exercise and during half-time, participants randomly ingested a placebo (PLC), 6.9% CHO, or 4.8% CHO plus 2.1% protein (CHO-P) supplements matched for color and taste. CHO-P resulted in longer RTF (23.02 ± 5.27 min) than did CHO (16.49 ± 3.25 min) and PLC (11.00 ± 2.80 min) (p < 0.05). Blood glucose was higher in CHO-P at the point of fatigue (4.68 ± 0.64) compared with CHO and PLC (3.92 ± 0.29 and 3.66 ± 0.36, respectively; p < 0.05). Ratings of perceived exertion were lower in the CHO-P subjects at the onset of exercise and towards the end of intermittent exercise when compared with the PLC and CHO subjects (p < 0.05). When protein was added to a CHO supplement, subsequent running capacity following limited recovery from intermittent exercise was enhanced. This improvement suggests that protein coingestion may exert an ergogenic benefit upon endurance capacity during intermittent activity.

Effects of caffeine on endurance capacity and psychological state in young females and males exercising in the heat

2017 ◽  
Vol 42 (1) ◽  
pp. 68-76 ◽  
Author(s):  
Silva Suvi ◽  
Saima Timpmann ◽  
Maria Tamm ◽  
Martin Aedma ◽  
Kairi Kreegipuu ◽  
...  
Keyword(s):  
Blood Lactate ◽  
Perceived Exertion ◽  
Current Knowledge ◽  
Psychological Effects ◽  
Peak Oxygen Consumption ◽  
Psychological State ◽  
Time To Exhaustion ◽  
Endurance Capacity ◽  
Ratings Of Perceived Exertion ◽  
Caffeine Ingestion

Acute caffeine ingestion is considered effective in improving endurance capacity and psychological state. However, current knowledge is based on the findings of studies that have been conducted on male subjects mainly in temperate environmental conditions, but some physiological and psychological effects of caffeine differ between the sexes. The purpose of this study was to compare the physical performance and psychological effects of caffeine in young women and men exercising in the heat. Thirteen male and 10 female students completed 2 constant-load walks (60% of thermoneutral peak oxygen consumption on a treadmill until volitional exhaustion) in a hot-dry environment (air temperature, 42 °C; relative humidity, 20%) after caffeine (6 mg·kg–1) and placebo (wheat flour) ingestion in a double-blind, randomly assigned, crossover manner. Caffeine, compared with placebo, induced greater increases (p < 0.05) in heart rate (HR) and blood lactate concentrations in both males and females but had no impact on rectal or skin temperatures or on walking time to exhaustion in subjects of either gender. Caffeine decreased (p < 0.05) ratings of perceived exertion and fatigue in males, but not in females. In females, but not in males, a stronger belief that they had been administered caffeine was associated with a shorter time to exhaustion. In conclusion, acute caffeine ingestion increases HR and blood lactate levels during exercise in the heat, but it has no impact on thermoregulation or endurance capacity in either gender. Under exercise-heat stress, caffeine reduces ratings of perceived exertion and fatigue in males but not in females.

Ratings of Perceived Exertion and Physiological Responses in Children During Exercise

2017 ◽  
Vol 38 (12) ◽  
pp. 897-901
Author(s):  
Jennifer Erichsen ◽  
Brandon Dykstra ◽  
Mary Hidde ◽  
Anthony Mahon
Keyword(s):  
Steady State ◽  
State Estimation ◽  
Perceived Exertion ◽  
Physiological Responses ◽  
Cycle Ergometer ◽  
Peak Oxygen Consumption ◽  
Ratings Of Perceived Exertion ◽  
Marked Variability ◽  
Target Intensity ◽  
Estimation Trial

AbstractOMNI ratings of perceived exertion (RPE) and physiological responses in children (n=7 boys, 8 girls, 11.1±1.0 years) were examined during estimation (graded exercise test [GXT] and steady-state) and production (steady-state) trials on a cycle ergometer. Peak oxygen consumption (VO2peak) was determined via a GXT with RPE estimated every 30 s. Later, two 6-min trials were completed: Participants 1) estimated RPE at ~75% of VO2peak, 2) produced a level of exertion corresponding to their RPE at ~75% of VO2peak during the GXT. Data analysis included a one-way MANOVA and a paired t-test. The target intensity during the GXT corresponded to 74.2±2.5% of VO2peak; the steady-state estimation and production trials were performed at 76.5±2.7% and 68.5±14.1% of VO2peak, respectively (p>0.05). Mean RPE at ~75% of VO2peak during the GXT and production trial was 6.7±1.5; during the steady-state estimation trial RPE was 5.8±2.0 (p>0.05). There were no differences (p>0.05) in the physiological responses. Participants estimated RPE similarly at ~75% of VO2peak during both graded and steady-state exercise, but when asked to produce a given RPE, marked variability was observed in physiological responses. These findings may have implications in optimizing exercise prescriptions for children.

Effects of Post-Hypnotic Suggestions on Muscular Endurance

1975 ◽  
Vol 40 (1) ◽  
pp. 131-139 ◽  
Author(s):  
Ira Albert ◽  
Melvin H. Williams
Keyword(s):  
Heart Rate ◽  
Perceived Exertion ◽  
Endurance Capacity ◽  
Ratings Of Perceived Exertion ◽  
Endurance Time ◽  
Heart Rate Data ◽  
Control Subjects ◽  
Experimental Subjects ◽  
And Control ◽  
Hypnotic Suggestions

This study examined the effects of post-hypnotic suggestions upon maximal endurance capacity, Borg ratings of perceived exertion, and heart rate. Experimental subjects were administered post-hypnotic suggestions to improve or decrease performance, and control subjects were given similar instructions during the awake state. Endurance time could be decreased significantly when the fatigue suggestion was given to experimental subjects, but performance could not be enhanced with the facilitating suggestion. Control subjects showed no significant changes across conditions. The Borg ratings indicated that experimental subjects experienced subjective changes as suggested by the hypnotist. In addition, analysis failed to find any significant differences for the heart-rate data.

Convergent Validity of CR100-Based Session Ratings of Perceived Exertion in Elite Youth Football Players of Different Ages

2020 ◽  
pp. 1-5
Author(s):  
Fabio R. Serpiello ◽  
Will G. Hopkins
Keyword(s):  
Convergent Validity ◽  
Perceived Exertion ◽  
Age Groups ◽  
Team Sports ◽  
Football Players ◽  
Ratings Of Perceived Exertion ◽  
Internal Load ◽  
Youth Football ◽  
The Relationship ◽  
Very High

Purpose: To assess the convergent validity of internal load measured with the CR100 scale in youth football players of 3 age groups. Methods: A total of 59 players, age 12–17 years, from the youth academy of a professional football club were involved in this study. Convergent validity was examined by calculating the correlation between session ratings of perceived exertion (sRPE) and Edwards load, a commonly used load index derived from the heart rate, with the data originating from 1 competitive season. The magnitude of the relationship between sRPE and Edwards load was obtained with weighted mean correlations and by assessing the effect of the change of the Edwards load on sRPE. Differences between the individuals’ intercepts and slopes were assessed by interpreting the SD representing the random effects (player identity and the interaction of player identity and scaled Edwards load). Probabilistic decisions about true (infinite sample) magnitudes accounting for sampling uncertainty were based on 1-sided hypothesis tests of substantial magnitudes, followed by reference Bayesian analysis. Results: Very high relationships exist between the sRPE and Edwards load across all age groups, with no meaningful differences in the magnitudes of the relationships between groups. Moderate to large differences between training sessions and games were found in the slopes of the relationships between the sRPE and Edwards load in all age groups. Finally, mostly small to moderate differences were observed between individuals for the intercepts and slopes of the relationships between the sRPE and Edwards load. Conclusion: Practitioners working in youth team sports can safely use the CR100 scale to track internal load.

Effect of induced alkalosis on perception of exertion during intermittent exercise

1989 ◽  
Vol 67 (5) ◽  
pp. 1862-1867 ◽  
Author(s):  
A. Swank ◽  
R. J. Robertson
Keyword(s):  
High Intensity ◽  
Perceived Exertion ◽  
Intermittent Exercise ◽  
Venous Blood ◽  
Exercise Bout ◽  
Cycle Ergometer ◽  
Placebo Control ◽  
Ratings Of Perceived Exertion ◽  
Exercise Protocol ◽  
Experimental Trials

The purpose of this study was to evaluate the effects of metabolic alkalosis on differentiated ratings of perceived exertion during intermittent high-intensity exercise. Six endurance-trained females participated as subjects in this investigation. Each subject underwent three separate experimental trials in which NaHCO3 was ingested in either a single (0.3 g NaHCO3/kg body wt) or periodic schedule (0.12 g NaHCO3/kg body wt initially, with 0.18 g/kg body wt distributed in equal doses before each 5-min exercise bout). Calcium carbonate served as a placebo control. An intermittent exercise protocol was used in which each subject rode a cycle ergometer at 90% maximum O2 consumption for 5 min. Within each acid-base condition, the exercise protocol was repeated three times with 10-min rest periods interspersed. Differentiated ratings of perceived exertion for the legs (RPE-L), chest (RPE-C), and overall body (RPE-O) were attenuated under alkalotic treatment relative to placebo control regardless of pattern of NaHCO3 administration. RPE-L, RPE-C, and RPE-O were negatively correlated to the bicarbonate concentration of venous blood. This investigation suggests that perception of effort during high-intensity intermittent exercise can be related to buffering capacity of the blood.

Wheelchair propulsion: effects of experience and push strategy on efficiency and perceived exertion

2008 ◽  
Vol 33 (5) ◽  
pp. 870-879 ◽  
Author(s):  
John P. Lenton ◽  
Neil E. Fowler ◽  
Lucas van der Woude ◽  
Victoria L. Goosey-Tolfrey
Keyword(s):  
Oxygen Consumption ◽  
Perceived Exertion ◽  
Maximal Exercise ◽  
Metabolic Cost ◽  
Peak Oxygen Consumption ◽  
Wheelchair Propulsion ◽  
Physiological Measures ◽  
Frequency Data ◽  
Ratings Of Perceived Exertion

The purpose of this study was to examine the role of wheeling experience on efficiency, metabolic cost, and differentiated ratings of perceived exertion (RPEs) during synchronous and asynchronous hand-rim propulsion with varying arm frequencies. Fourteen able-bodied (AB) male participants and 8 male wheelchair sportsmen (WS) performed tests of peak oxygen consumption for both propulsion modes. Subsequently, 2 series of five 4-min sub-maximal exercise bouts were completed at an individualized velocity (60% of peak oxygen consumption). Arm frequencies consisted of the freely chosen frequency (FCF), followed by 4 counter-balanced paced trials pushing at 60%, 80%, 120%, and 140% of the FCF. Efficiency indices (gross, GE; work, WE) were determined and peripheral (RPE-P), central (RPE-C), and overall (RPE-O) RPEs were recorded. The GE (6.4% vs. 8.4%) and WE (11.3% vs. 15.1%) were significantly higher in WS than in AB (p = 0.001). Trends in the oxygen consumption, GE, and WE data were similar in both groups, propulsion mode, and arm frequency. Data suggest that 80% FCF resulted in improved efficiency for both propulsion mode and group, although the differences between those arm frequencies immediately above and below were non-significant. Lower RPE scores corresponded with higher efficiency values. Regardless of group there were significant differences (p = 0.001) between the differentiated RPE measures, whereby RPE-P was on average always the highest score (13.1) and RPE-C the lowest (11.1; RPE-O was 12.2). In conclusion, despite the anticipated differences in efficiency between the WS and AB participants, this study confirmed that psycho-physiological measures produce similar trends to physiological measures with manipulations of both arm frequency and propulsion mode.

scholarly journals The Effects of Pre-Game Carbohydrate Intake on Running Performance and Substrate Utilisation during Simulated Gaelic Football Match Play

Nutrients ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1392
Author(s):  
Luke O’Brien ◽  
Kieran Collins ◽  
Richard Webb ◽  
Ian Davies ◽  
Dominic Doran ◽  
...  
Keyword(s):  
High Speed ◽  
Football Players ◽  
Glycerol Concentration ◽  
Half Time ◽  
Match Play ◽  
Running Performance ◽  
Positioning Systems ◽  
Oxidation Rates ◽  
Significant Difference ◽  
Football Match

Background: Previous research has reported that elite Gaelic football players’ carbohydrate (CHO) intakes are sub-optimal, especially, in the lead up to competitive matches. Despite clear decrements in running performance across elite Gaelic football matches, there are no studies that have investigated nutrition interventions on match-related Gaelic football performance. The aim of this study was to determine whether a higher-CHO diet in line with sports nutrition guidelines can improve Gaelic football-related performance compared to lower CHO intakes previously observed in Gaelic footballers. Methods: Twelve Gaelic football players completed a Gaelic football simulation protocol (GFSP) on two occasions after consuming a high-CHO diet (7 g·kg−1) (HCHO) or an energy-matched lower-CHO diet (3.5 g·kg−1) (L-CHO) for 48 h. Movement demands and heart rate were measured using portable global positioning systems devices. Countermovement jump height (CMJ) and repeated-sprint ability (RSA) were measured throughout each trial. Expired respiratory gases were collected throughout the trial using a portable gas analyser. Blood samples were taken at rest, half-time, and post-simulation. Results: There was no significant difference in total distance (p = 0.811; η2 = 0.005) or high-speed running distance (HSRD) covered between both trials. However, in the second half of the HCHO trial, HSRD was significantly greater compared to the second half of the LCHO trial (p = 0.015). Sprint distance covered during GFSP was significantly greater in HCHO (8.1 ± 3.5 m·min−1) compared with LCHO (6.4 ± 3.2 m·min−1) (p = 0.011; η2 = 0.445). RSA performance (p < 0.0001; η2 = 0.735) and lower body power (CMJ) (p < 0.0001; η2 = 0.683) were significantly greater during the HCHO trial compared to LCHO. Overall CHO oxidation rates were significantly greater under HCHO conditions compared to LCHO (3.3 ± 0.5 vs. 2.7 ± 0.6 g·min−1) (p < 0.001; η2 = 0.798). Blood lactate concentrations were significantly higher during HCHO trial versus LCHO (p = 0.026; η2 = 0.375). There were no significant differences in plasma glucose, non-esterified fatty acids (NEFAs), and glycerol concentration between trials. In both trials, all blood metabolites were significantly elevated at half-time and post-trial compared to pre-trial. Conclusion: These findings indicate that a higher-CHO diet can reduce declines in physical performance during simulated Gaelic football match play.

scholarly journals Intensity selection and regulation using the OMNI scale of perceived exertion during intermittent exercise

2013 ◽  
Vol 38 (9) ◽  
pp. 960-966 ◽  
Author(s):  
Mark A. Schafer ◽  
Fredric L. Goss ◽  
Robert J. Robertson ◽  
Elizabeth F. Nagle-Stilley ◽  
Kevin Kim
Keyword(s):  
Oxygen Uptake ◽  
Perceived Exertion ◽  
Intermittent Exercise ◽  
Ratings Of Perceived Exertion ◽  
Graded Exercise Test ◽  
Treadmill Speed ◽  
Graded Exercise ◽  
Omni Scale ◽  
Counterbalance Order ◽  
Estimation Trial

The purpose of this investigation was to determine if subjects can self-regulate exercise intensity during intermittent exercise by using ratings of perceived exertion. Thirty-one subjects completed an estimation trial maximal treadmill graded exercise test (GXT). Using the oxygen uptake and ratings of perceived exertion (RPE) from the GXT, target RPEs that corresponded to 50% and 70% of oxygen uptake reserve were determined. During the subsequent 20 min production trial, subjects titrated treadmill speed and grade to elicit the target RPEs that were presented in 2 counterbalanced orders (counterbalance order I (70%–50% of oxygen uptake reserve) or counterbalance order II (50%–70% of oxygen uptake reserve)). Heart rate (HR) and oxygen uptake were higher in the production trial compared with the estimation trial for counterbalance order I (p < 0.001) at an RPE that corresponded to 50% of oxygen uptake reserve. There was no difference in HR and oxygen uptake between the estimation and production trial for counterbalance order II (p < 0.05). HR was higher in the production trial compared with estimation trial for counterbalance order I (p < 0.05) at an RPE that corresponded to 70% of oxygen uptake reserve. There was no difference in HR between the estimation and production trials for counterbalance order II (p < 0.05). At an RPE that corresponded to 70% of oxygen uptake reserve, there was no difference in the oxygen uptake between the estimation and production trials (p < 0.05). A difference in HR (p < 0.05) and oxygen uptake (p < 0.05) between the 2 prescribed production trial intensities was indicated. The subjects were able to utilize RPE to self-regulate intensity during 20 min of exercise at varying intensity when beginning with the target RPE that corresponded to 50% of oxygen uptake reserve.

Blood Doping in Sports

1980 ◽  
Vol 10 (3) ◽  
pp. 331-339 ◽  
Author(s):  
Melvin H. Williams
Keyword(s):  
Perceived Exertion ◽  
Autologous Blood ◽  
Ergogenic Aid ◽  
Endurance Capacity ◽  
Ratings Of Perceived Exertion ◽  
Blood Doping ◽  
Research Designs ◽  
Doping In Sports ◽  
Psychological Parameters

Blood doping, or the infusion of autologous blood into trained athletes, has been theorized to increase endurance capacity. However, a review of 16 studies which have investigated various aspects relative to the effect of blood doping on endurance capacity and related physiological and psychological parameters, such as exercise HR, VO2max, and ratings of perceived exertion, has revealed inconsistent results. Due to the fact that most research designs employed to date have experienced some methodological irregularities, the efficiency of blood doping as an ergogenic aid for athletes has not been established.

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