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Kapria-Jad Josaphat, Élise Labonté-Lemoyne, Sylvain Sénécal, Pierre-Majorique Léger and Marie-Eve Mathieu

Background: Sedentariness has been shown to increase energy intake and is associated with increased obesity prevalence. Active workstations are used to implement physical activity interventions in workplaces, but it is unclear if they can lead to reductions in body weight. This study aims to observe the acute impact of a standing desk on energy intake and appetite sensations. Methods: Participants came to the laboratory, where they were randomly assigned to a seated or a standing desk. They completed a work session (∼75 min) during which they performed cognitive tasks and reported their levels of stress. Following this, they had a 15-minute break during which buffet-type snacks were served. Subjects were asked to rate their appetite sensations on visual analog scales. Results: Thirty-six normal-weight men and women aged 24.3 (4.3) years participated in this study. Energy intake from snacks was similar (P = .472) between participants who sat (427.8 [286.9] kcal) and the ones who stood (461.2 [272.8] kcal) during the work session. There was no difference in satiety quotients around the snack and no significant interaction time × condition for appetite sensations. Conclusion: The use of a standing desk for 75 minutes did not increase food consumption following a meal.

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Samuel Ryan, Thomas Kempton and Aaron J. Coutts

Purpose: To apply data reduction methods to athlete-monitoring measures to address the issue of data overload for practitioners of professional Australian football teams. Methods: Data were collected from 45 professional Australian footballers from 1 club during the 2018 Australian Football League season. External load was measured in training and matches by 10-Hz OptimEye S5 and ClearSky T6 GPS units. Internal load was measured via the session rate of perceived exertion method. Perceptual wellness was measured via questionnaires completed before training sessions with players providing a rating (1–5 Likert scale) of muscle soreness, sleep quality, fatigue, stress, and motivation. Percentage of maximum speed was calculated relative to individual maximum velocity recorded during preseason testing. Derivative external training load measures (total daily, weekly, and monthly) were calculated. Principal-component analyses (PCAs) were conducted for Daily and Chronic measures, and components were identified via scree plot inspection (eigenvalue > 1). Components underwent orthogonal rotation with a factor loading redundancy threshold of 0.70. Results: The Daily PCA identified components representing external load, perceived wellness, and internal load. The Chronic PCA identified components representing 28-d speed exposure, 28-d external load, 7-d external load, and 28-d internal load. Perceived soreness did not meet the redundancy threshold. Conclusions: Monitoring player exposure to maximum speed is more appropriate over chronic than short time frames to capture variations in between-matches training-cycle duration. Perceived soreness represents a distinct element of a player’s perception of wellness. Summed-variable and single-variable approaches are novel methods of data reduction following PCA of athlete monitoring data.

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Laura Martin and Martin Camiré

Coaches have been shown to play key roles in the life-skills development and transfer process. The purpose of the study was to examine coaches’ approaches to teaching life skills and their transfer in youth sport. A multiple case study design was employed. Each case was composed of one coach and at least two of their athletes involved in youth baseball, rugby, soccer, and sailing. The data collection involved pre- and postseason interviews and in-season journaling with coaches, as well as postseason interviews with athletes. The results indicated that the coaches predominantly used implicit approaches, with just over half identified as using some explicit approaches to teach life skills. The coaches discussed several factors that influenced their decisions to use or not use explicit life-skills teaching approaches. The results have implications for future research and applied efforts aimed at maximizing the developmental gains athletes can derive from their participation in sport.

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Steve M. Smith, Stewart T. Cotterill and Hazel Brown

The psychological environment where sporting activity is undertaken has been suggested to influence performance. The coach orchestrates practice activities and their perception of the psychological environment has been regularly evaluated in competition research but not in practice. The aim of this study was to explore coach perceptions of the psychological influencing factors present in the practice environment. Participants were six U.K. academy basketball coaches (mean age = 35 years). Data were collected through semi-structured interviews and analyzed using interpretative phenomenological analysis. Five superordinate themes were constructed from data analysis, which were player characteristics, team-first orientation, current performance perceptions, coach characteristics, and coaching structure. Results suggest that the coach has a unique insight into the psychological influencing factors of the practice environment. Combined with the practice environment framework offered by Smith, Cotterill, and Brown, a model is offered to aid practitioners in understanding the interrelatedness of psychological influencing factors in the practice environment.

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Laurence S. Warren-West and Robin C. Jackson

An extended time window was used to examine susceptibility to, and detection of, deception in rugby union. High- and low-skilled rugby players judged the final running direction of an opponent “cutting” left or right, with or without a deceptive sidestep. Each trial was occluded at one of eight time points relative to the footfall after the initial (genuine or fake) reorientation. Based on response accuracy, the results were separated into deception susceptibility and deception detection windows. Signal-detection analysis was used to calculate the discriminability of genuine and deceptive actions (d') and the response bias (c). High-skilled players were less susceptible to deception and better able to detect when they had been deceived, accompanied by a reduced bias toward perceiving all actions as genuine. By establishing the time window in which players become deceived, it will now be possible to identify the kinematic sources that drive deception.

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Peter M. Fowler, Wade Knez, Heidi R. Thornton, Charli Sargent, Amy E. Mendham, Stephen Crowcroft, Joanna Miller, Shona Halson and Rob Duffield

Purpose: To assess the efficacy of a combined light exposure and sleep hygiene intervention to improve team-sport performance following eastward long-haul transmeridian travel. Methods: Twenty physically trained males underwent testing at 09:00 and 17:00 hours local time on 4 consecutive days at home (baseline) and the first 4 days following 21 hours of air travel east across 8 time zones. In a randomized, matched-pairs design, participants traveled with (INT; n = 10) or without (CON; n = 10) a light exposure and sleep hygiene intervention. Performance was assessed via countermovement jump, 20-m sprint, T test, and Yo-Yo Intermittent Recovery Level 1 tests, together with perceptual measures of jet lag, fatigue, mood, and motivation. Sleep was measured using wrist activity monitors in conjunction with self-report diaries. Results: Magnitude-based inference and standardized effect-size analysis indicated there was a very likely improvement in the mean change in countermovement jump peak power (effect size 1.10, ±0.55), and likely improvement in 5-m (0.54, ±0.67) and 20-m (0.74, ±0.71) sprint time in INT compared with CON across the 4 days posttravel. Sleep duration was most likely greater in INT both during travel (1.61, ±0.82) and across the 4 nights following travel (1.28, ±0.58) compared with CON. Finally, perceived mood and motivation were likely worse (0.73, ±0.88 and 0.63, ±0.87) across the 4 days posttravel in CON compared with INT. Conclusions: Combined light exposure and sleep hygiene improved speed and power but not intermittent-sprint performance up to 96 hours following long-haul transmeridian travel. The reduction of sleep disruption during and following travel is a likely contributor to improved performance.

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Monica A.F. Lounsbery and Thomas L. McKenzie

This paper reviews the authors’ evolution as kinesiology scholars to a public health focus via their research on school physical activity (PA) and policy. The authors present key findings from their work, including their recent focus group discussion with 20 school leaders, to substantiate their perspectives about the role that the American Kinesiology Association could play in supporting public health goals and promoting school PA policy. The authors conclude the paper by appealing to American Kinesiology Association to clearly identify PA and its promotion as a central area of study in kinesiology, strengthen its ties to public health, and advocate for putting the “physical” back in the National Physical Education Standards.

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Corey A. Pew, Sarah A. Roelker, Glenn K. Klute and Richard R. Neptune

The coupling between the residual limb and the lower-limb prosthesis is not rigid. As a result, external loading produces movement between the prosthesis and residual limb that can lead to undesirable soft-tissue shear stresses. As these stresses are difficult to measure, limb loading is commonly used as a surrogate. However, the relationship between limb loading and the displacements responsible for those stresses remains unknown. To better understand the limb motion within the socket, an inverse kinematic analysis was performed to estimate the motion between the socket and tibia for 10 individuals with a transtibial amputation performing walking and turning activities at 3 different speeds. The authors estimated the rotational stiffness of the limb-socket body to quantify the limb properties when coupled with the socket and highlight how this approach could help inform prosthetic prescriptions. Results showed that peak transverse displacement had a significant, linear relationship with peak transverse loading. Stiffness of the limb-socket body varied significantly between individuals, activities (walking and turning), and speeds. These results suggest that transverse limb loading can serve as a surrogate for residual-limb shear stress and that the setup of a prosthesis could be individually tailored using standard motion capture and inverse kinematic analyses.