The primary purpose of this research was to examine the influence of different normative (descriptive, injunctive) messages on individual self-reported effort in sport. Adult recreational volleyball athletes (n = 58) reported their self-perceived effort, were randomly assigned through their team designation to one of three conditions (descriptive norm, injunctive norm, control) and then received multiple e-mail messages specific to their condition motivating them to work hard. Participants reported their self-perceived effort a second time after receipt of these messages. The results from a one-way ANCOVA, controlling for initial perceived effort, revealed that those in the normative conditions reported greater perceived effort than those in the control condition. Preliminary evidence is provided suggesting that individual self-reported effort may be significantly impacted by the perception of what others are doing and what others approve of within that environment (i.e., normative information).
Alyson J. Crozier and Kevin S. Spink
Mary Lou Veal and Nick Compagnone
Tim J. Gabbett, Ben Walker and Shane Walker
To investigate the influence of prior knowledge of exercise duration on the pacing strategies employed during gamebased activities.
Twelve semiprofessional team-sport athletes (mean ± SD age 22.8 ± 2.1 y) participated in this study. Players performed 3 small-sided games in random order. In one condition (Control), players were informed that they would play the small-sided game for 12 min and then completed the 12-min game. In a 2nd condition (Deception), players were told that they would play the small-sided game for 6 minutes, but after completing the 6-min game, they were asked to complete another 6 min. In a 3rd condition (Unknown), players were not told how long they would be required to play the small-sided game, but the activity was terminated after 12 min. Movement was recorded using a GPS unit sampling at 10 Hz. Post hoc inspection of video footage was undertaken to count the number of possessions and the number and quality of disposals.
Higher initial intensities were observed in the Deception (130.6 ± 3.3 m/min) and Unknown (129.3 ± 2.4 m/min) conditions than the Control condition (123.3 ± 3.4 m/min). Greater amounts of high-speed running occurred during the initial phases of the Deception condition, and more low-speed activity occurred during the Unknown condition. A moderately greater number of total skill involvements occurred in the Unknown condition than the Control condition.
These findings suggest that during game-based activities, players alter their pacing strategy based on the anticipated endpoint of the exercise bout.
Luis Peñailillo, Karen Mackay and Chris R. Abbiss
increases with alterations in physiological stress such as an increase in oxygen consumption, an increase in metabolic acidosis, or reductions in carbohydrate stores. 5 , 22 , 23 This is not to state that perceived effort only arises from corollary discharges of central motor command and perceived exertion
Luana T. Rossato, Camila T.M. Fernandes, Públio F. Vieira, Flávia M.S. de Branco, Paula C. Nahas, Guilherme M. Puga and Erick P. de Oliveira
of the rest duration. Immediately after the mouth rinse, subjects commenced their run to exhaustion test on the treadmill at velocity equivalent to 100% of individual’s VO 2 max. Every 30 seconds during the test, individuals were questioned about their ratings of perceived effort (using the Borg
Tristan L. Wallhead and Nikos Ntoumanis
This study looked at the influence of a Sport Education intervention program on students’ motivational responses in a high school physical education setting. Two intact groups were assigned curricular interventions: the Sport Education group (n = 25), which received eight 60-min lessons, and the comparison group (n = 26), which received a traditional teaching approach to sport-based activity. Pre- and postintervention measures of student enjoyment, perceived effort, perceived competence, goal orientations, perceived motivational climate, and perceived autonomy were obtained for both groups. Repeated-measures ANOVAs showed significant increases in student enjoyment and perceived effort in the Sport Education group only. Hierarchical regression analyses revealed that increases in task-involving climate and perceived autonomy explained a significant amount of unique variance in the Sport Education students’ postintervention enjoyment, perceived effort, and perceived competence responses. The results suggest that the Sport Education curriculum may increase perceptions of a task-involving climate and perceived autonomy, and in so doing, enhance the motivation of high school students toward physical education.
Tristan Wallhead, Alex C. Garn, Carla Vidoni and Charli Youngberg
Sport Education has embedded pedagogical strategies proposed to reduce the prevalence of amotivation in physical education. The purpose of this study was to provide an examination of the game play participation rates of amotivated students within a Sport Education season. A sample of 395 high school students participated in a season of team handball. A multistep cluster analysis approach revealed three motivational profiles: amotivated, moderate and high clusters. A priori analyses revealed differences in perceived effort, enjoyment, and need satisfaction across the three profile groups. Game play participation rates coded throughout the season revealed no significant differences in ball engagement or success rates across motivational profile groups. A significant difference occurred in active game participation between the high and amotivated students. Results suggest that Sport Education elicits a level of inclusive game play participation across students of different motivational profiles.
Chris Easton, Stephen Turner and Yannis P. Pitsiladis
The authors examined the effects of combined creatine (Cr) and glycerol (Gly) supplementation on responses to exercise in the heat. Subjects (N = 24) were matched for body mass and assigned to either a Cr or placebo (Pl) group. Twice daily during two 7-d supplementation regimens, the Cr group received 11.4 g of Cr·H2O and the Pl group received 11.4 g of glucose. Subjects in both groups also ingested 1 g of Gly/kg body mass (twice daily) in either the first or the second supplementation regimen. This design allowed 4 possible combinations of supplements to be examined (Pl/Pl, Pl/Gly, Cr/Pl, and Cr/Gly). Exercise trials were conducted pre- and post supplementation at 30 °C and 70% relative humidity. In the Pl group, total body water (TBW) increased by 0.50 ± 0.28 L after Gly and in the Cr group by 0.63 ± 0.33 L after Pl and by 0.87 ± 0.21 L after Gly. Both Cr/Pl and Cr/Gly resulted in significantly attenuated heart rate, rectal temperature, and perceived effort during exercise, although no regimen had any effect on performance. The addition of Gly to Cr significantly increased TBW more than Cr alone (P = 0.02) but did not further enhance the attenuation in HR, Tre, and RPE during exercise. These data suggest that combined Cr and Gly is an effective method of hyper hydration capable of reducing thermal and cardiovascular responses.
Diego B. Souza, Michael Duncan and Marcos D. Polito
Purpose: To examine the effects of acute caffeine (CAF) intake on physical performance in 3 sets of unilateral knee extensions with blood-flow restriction. Methods: In a double-blind crossover design, 22 trained men ingested 6 mg·kg−1 of CAF or a placebo (PLA), 1 h prior to performing unilateral knee-extension exercise with blood-flow restriction until exhaustion (30% of 1 maximal repetition). Results: There was a significant difference in the number of repetitions between the CAF and PLA conditions in the first set (28.3 [5.3] vs 23.7 [3.2]; P = .005), second set (11.6 [3.1] vs 8.9 [2.9]; P = .03), and total repetitions performed across the 3 sets (44.5 [9.4] vs 35.0 [6.6]; P = .001). Blood lactate was also significantly different (P = .03) after exercise between the CAF (7.8 [1.1] mmol·L−1) and PLA (6.0 [0.9] mmol·L−1). In regard to pain perception, there was a difference between the CAF and PLA in the second (6.9 [1.5] vs 8.4 [1.4]; P = .04) and third sets (8.7 [0.4] vs 9.5 [0.6]; P = .01). No differences were found for perceived effort. Conclusion: Acute caffeine intake increases performance and blood lactate concentration and reduces perception of pain in unilateral knee-extension exercise with blood-flow restriction.
Vasilis Nikolopoulos, Melissa J. Arkinstall and John A. Hawley
The purpose of this study was to determine the effect of carbohydrate ingestion before and during intense constant load cycling to volitional fatigue on surface electromyographic (sEMG) activity from the vastus lateralis (VL) and vastus medialis (VM) muscles. After 24-h diet and training control, 8 well-trained subjects [maximal O2 uptake (VO2max) 66 ± 2 ml · kg–1· min–1; mean ± SD] ingested 8 ml · kg–1 of either a 6.4% carbohydrate-electrolyte (CHO) or a placebo (PLA) solution immediately before, followed by 2 ml · kg–1 of the same solution every 15 min while cycling to exhaustion at 84 ± 1% of VO2max. Exercise time to fatigue was 13% longer with CHO ingestion compared to PLA (58:54 ± 8:48 vs. 51:18 ± 5:54 min:s, NS). VO2 (4.22 ± 0.11 vs. 4.20 ± 0.14 L · min–1), heart rate (172 ± 4 vs. 176 ± 4 beats · min–1), ratings of perceived effort (18 ± 0.1 vs. 19 ± 0.1), and rates of carbohydrate oxidation (314 ± 28 vs. 324 ± 26 μmol · kg–1 · min–1) were similar for both PLA and CHO at exhaustion. There was no main treatment effect of CHO ingestion on blood glucose or lactate concentrations, nor plasma prolactin levels either during exercise or at fatigue. However, CHO ingestion attenuated the rise in EMG root mean square (RMS) activity during the latter stages (>45 min) of exercise and at the point of exhaustion for both VM (0.325 ± 0.010 vs. 0.403 ± 0.020 mV; p = .006) and VL (0.298 ± 0.011 vs. 0.370 ± 0.007 mV; p = .0004). We conclude that in well-trained subjects, the ingestion of carbohydrate attenuated the increase in surface electromyographic activity during intense, constant load cycling leading to exhaustion in ~1 h. The precise mechanism(s) underlying this effect cannot be attributed to alterations in CHO availability but, instead, may be linked to changes in afferent sensory input.