variables. The magnitude of the individual response to external load has, however, not been previously investigated. In this study we aimed, first, to model the within-player and the between-player effects of different external load variables on sRPE-TL in elite football. Second, to model the magnitude of
Håvard Wiig, Thor Einar Andersen, Live S. Luteberget and Matt Spencer
Mary O. Whipple, Erica N. Schorr, Kristine M.C. Talley, Ruth Lindquist, Ulf G. Bronas and Diane Treat-Jacobson
headings in the article). “adj3” denotes a search in which the first term is within three words of the second term (e.g., “differ* adj3 respon*” would capture the phrase “difference in individual response”). Selection of Studies To be eligible for inclusion in this review, articles had to meet the
Heidi R. Thornton, Jace A. Delaney, Grant M. Duthie and Ben J. Dascombe
compensate for large measurement errors. 10 Means and SDs should be reported, as these depict the variation in the responses, reflecting the effect of the treatment between individuals. The SD at baseline may be used to assess the magnitudes of effects and individual responses by standardization. 10 These
Christian Cook, C. Martyn Beaven, Liam P. Kilduff and Scott Drawer
This study aimed to determine whether caffeine ingestion would increase the workload voluntarily chosen by athletes in a limited-sleep state.
In a double-blind, crossover study, 16 professional rugby players ingested either a placebo or 4 mg/kg caffeine 1 hr before exercise. Athletes classified themselves into nondeprived (8 hr+) or sleep-deprived states (6 hr or less). Exercise comprised 4 sets of bench press, squats, and bent rows at 85% 1-repetition maximum. Athletes were asked to perform as many repetitions on each set as possible without failure. Saliva was collected before administration of placebo or caffeine and again before and immediately after exercise and assayed for testosterone and cortisol.
Sleep deprivation produced a very large decrease in total load (p = 1.98 × 10−7). Caffeine ingestion in the nondeprived state resulted in a moderate increase in total load, with a larger effect in the sleep-deprived state, resulting in total load similar to those observed in the nondeprived placebo condition. Eight of the 16 athletes were identified as caffeine responders. Baseline testosterone was higher (p < .05) and cortisol trended lower in non-sleep-deprived athletes. Changes in hormones from predose to preexercise correlated to individual workload responses to caffeine. Testosterone response to exercise increased with caffeine compared with placebo, as did cortisol response.
Caffeine increased voluntary workload in professional athletes, even more so under conditions of self-reported limited sleep. Caffeine may prove worthwhile when athletes are tired, especially in those identified as responders.
Kristy Martin, Kevin G. Thompson, Richard Keegan and Ben Rattray
< .01). Physical Endurance Test There was no significant difference in the mean time to exhaustion between the control and mental exertion conditions (control: 628 ± 247 s vs. mental exertion: 601 ± 245 s, p = .074, d = 0.110). The individual responses were highly varied with 14 participants
Carolina Lundqvist and Göran Kenttä
The purpose of this study was to psychometrically evaluate the Emotional Recovery Questionnaire (EmRecQ) and to describe athletes’ individual response patterns in five repeated assessments using the EmRecQ. Three samples were used. Samples 1 and 2 consisted of 192 and 379 (Mean age 16.4 years, SD = 0.7 and Mean age: 17.0 years, SD = 1.1) elite athletes from different sports. The third sample consisted of 20 (Mean age: 21.3, SD = 19.0) female elite basketball players. The EmRecQ is a 22-item questionnaire that assesses Happiness, Security, Harmony, Love, and Vitality. Results showed acceptable weighted omega reliability and construct reliability. Confirmatory factor analyses supported the a priori specified five-factor correlated model. Case profiles of repeated assessments revealed individual response patterns of the separate EmRecQ subscales that corresponded well with rated training load and total quality of recovery. The findings provide support for the EmRecQ’s psychometric properties and applied usefulness.
David S. Rowlands, Rhys M. Thorp, Karin Rossler, David F. Graham and Mike J. Rockell
Carbohydrate ingestion after prolonged strenuous exercise enhances recovery, but protein might also be important. In a crossover with 2-wk washout, 10 cyclists completed 2.5 h of intervals followed by 4-h recovery feeding, provided 218 g protein, 435 g carbohydrate, and 79 g fat (protein enriched) or 34 g protein, 640 g carbohydrate, and 79 g fat (isocaloric control). The next morning, cyclists performed 10 maximal constant-work sprints on a Velotron cycle ergometer, each lasting ~2.5 min, at ~5-min intervals. Test validity was established and test reliability and the individual response to the protein-enriched condition estimated by 6 cyclists’ repeating the intervals, recovery feeding, and performance test 2 wk later in the protein-enriched condition. During the 4-h recovery, the protein-enriched feeding had unclear effects on mean concentrations of plasma insulin, cortisol, and growth hormone, but testosterone was 25% higher (90% confidence limits, ± 14%). Protein enrichment also reduced plasma creatine kinase by 33% (±38%) the next morning and reduced tiredness and leg-soreness sensations during the sprints, but effects on mean sprint power were unclear (–1.4%, ±4.3%). The between-subjects trial-to-trial coefficient of variation in overall mean sprint power was 3.1% (±3.4%), whereas the variation in the protein-enriched condition was 5.9% (±6.9%), suggesting that individual responses to the protein-enriched treatment contributed to the unclear performance outcome. To conclude, protein-enriched recovery feeding had no clear effect on next-day performance.
Gail Frost, Oded Bar-Or, James Dowling and Catherine White
This study examined habituation to treadmill walking or running in children. Twenty-four boys and girls, ages 7–11, completed six 6-min trials of treadmill exercise at one of these speeds: (a) comfortable walking pace (CWP), (b) CWP + 15%, (c) running at CWP + 3 km·hr−1, or (d) running as above + 15%. The six trials were repeated in a second visit. The a priori criterion for habituation was a decrease in steady state values of oxygen uptake (V̇O2), heart rate (HR), respiratory exchange ratio (RER), and stride rate (SR) or an increase in stride length (SL) and hip joint vertical amplitude (HA) from one trial to the next. There was no consistent pattern indicating habituation for the group. Many trials and more than one day of testing do not appear to improve the stability of the metabolic or kinematic variables. The lack of consistency in individual responses suggests that monitoring subjects’ habituation individually is important.
Mary L. Henninger
The purpose of this study was to understand factors that influenced the career trajectories of veteran urban secondary physical education teachers. The careers of these teachers were studied from the theoretical perspectives of teacher efficacy and teacher career development. Participants included 9 secondary urban physical education teachers (4 females and 5 males). Data were collected using 7 qualitative methods. Data analysis involved constant comparison through the processes of open and axial coding followed by a cross-case comparison (Strauss & Corbin, 1998). Findings indicated that organizational contexts of these veteran urban physical education teachers played the most salient role in shaping their beliefs and behaviors. Although the organizational contextual factors reported were similar across this group of teachers, individual responses differed greatly. These differences delineated teachers into two groups of stayers: lifers and troupers. Knowledge of workplace conditions’ specific effects on teachers’ career trajectories provides valuable information for initial preparation of novice teachers and for further professional development.
Lisa M. Van Landuyt, Panteleimon Ekkekakis, Eric E. Hall and Steven J. Petruzzello
Traditional conceptions of the exercise–affect relationship postulate that moderate-intensity exercise leads to positive affective changes in all or most individuals, and it can, therefore, be prescribed for all individuals involved in exercise programs. This study investigated whether this assumption is true, not only at the level of group averages but also at the level of individuals. Affect was assessed before, during, and after a session of moderate-intensity cycle ergometry using a dimensional conceptualization of affect. Examination of individual responses revealed a diversity of patterns that was masked by aggregate-based analyses. Mean ratings of affective valence were shown to remain stable during exercise, but in actuality almost half of the individuals experienced progressive improvement, whereas the other half experienced progressive deterioration. The diversity of individual affective responses must be taken into account in formulating conceptual models of the exercise–affect relationship and deriving public health physical activity recommendations.