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This study examined the effect of time of day on immediate recall of motor skills (i.e., tactical behaviors in basketball) from different external visualizations. First-year students from a public university in sports science (novice practitioners, 18.96 ± 0.57 years) were quasi-randomly assigned to three experimental conditions: video modeling by experts, a sequential-with-tracing presentation of pictures, or a sequential-without-tracing presentation of pictures. Morning and late afternoon sessions were conducted involving study phases and immediate-recall tests (i.e., comprehension and game performance tests). Oral temperature and mood states were also measured at both times of day. The results revealed that participants exhibited better recall performances in the morning, irrespective of the visualization format used. At both time of day, tactical behaviors were better recalled from video modeling rather than the two sequential presentations of pictures. In addition, providing the learner with a permanent visual trace of the previous states improves the immediate recall of tactical skills from a sequential presentation of pictures, at both time of day. Furthermore, morning sessions resulted in lower oral temperature, lower negative mood, and higher positive mood, compared with afternoon sessions. Implications for using external visualizations aimed at the acquisition of motor skills, particularly tactical behaviors, are discussed.

Background: It is essential to better characterize the energetic profile of individuals during very low-intensity physical activity. The objectives of the present study were to determine whether the saver profile from sit-to-stand persists during light physical activity and characterize patterns in substrate utilization from sit-to-stand and during very low-intensity physical activity in healthy men and women. Methods: Sixty-two healthy adults (38 women) performed an experimental sequence that corresponded to 15-minute sitting (SIT1), followed by 15-minute standing (STAND), 15-minute sitting again (SIT2), and finally 15 minutes of light cycling. Continuous indirect calorimetry was allowed to calculate energy expenditure (EE) and respiratory quotient through the entire sequence. Savers and nonsavers (<5% and ≥ 5% increase in EE from sitting to standing, respectively) were determined. Results: There was an interaction effect in EE between savers and nonsavers through the whole sequence (P = .008). Only nonsavers (71%) exhibited a significant increase in EE from SIT1 to STAND (P < .001). Nonsavers and savers significantly increased EE during 15 minutes of light cycling relative to sitting or standing (P < .001), without any difference between groups. The percentage of change in respiratory quotient from SIT1 to STAND was significantly different between the 2 groups, with increased values in savers and decreased values in nonsavers (P = .03). Significantly lower values in respiratory quotient and EE were found during 15 minutes of light cycling in women compared with men (P < .001). Conclusions: It is essential to determine individuals’ energetic phenotype to determine those who may benefit more from strategies such as standing or light physical activity. The sexual dimorphism in terms of substrate use during such exercise should be considered.

Purpose: This study aimed to compare running economy across habituated and nonhabituated advanced footwear technology (AFT) in trained long-distance runners. Methods: A total of 16 participants completed up to six 5-minute trials in 1 to 3 pairs of their own habituated shoes and 3 different and standardized AFTs at individual marathon pace. We measured oxygen uptake and carbon dioxide production and expressed running economy as oxygen uptake (in milliliters oxygen per kilogram per minute), oxygen cost of transport (oxygen per kilogram per minute), energetic cost (in watts per kilogram), and energetic cost of transport (in joules per kilogram per kilometer). We used linear mixed-effect models to evaluate differences. Relative shoe weight and shoe mileage (distance worn during running) were covariates. Results: Forty-eight standardized and 29 individual AFT conditions were measured (mileage 117.0 [128.8] km, range 0–522 km; 25 habituated 135.7 [129.2] km, range 20–522 km; 4 nonhabituated 0 [0] km, range 0–0 km). Rating of perceived exertion, blood [La], and respiratory exchange ratio ranged from 9 to 15, 1.11 to 4.54 mmol/L, and 0.76 to 1.01. There was no effect for habituation on energetic cost of transport (t _habituation = −.232, P = .409, b = −0.006; 95% CI, −0.058 to 0.046) or other running economy metrics. Neither shoe weight nor shoe mileage had an effect. Conclusions: Our results suggest that habituation to AFTs does not result in greater benefits in the use of AFTs. This means that implementation in training may not be needed, even if we cannot rule out any other possible benefits of habituation at this stage, such as adaptation of the musculoskeletal system.

Background: Research suggests there is considerable opportunity to improve children’s movement behaviors while they are being cared for by their grandparents. An understanding of the extent to which grandparent practices facilitate children’s engagement in physical activity is critical to the development of health interventions targeting grandparent caregivers. This study examined the activity-related beliefs and practices of grandparents and their association with grandchildren’s engagement in various movement behaviors while in grandparental care. Methods: Australian grandparents (N = 1190; 60% women) who provided regular care to a grandchild aged 3–14 years were recruited via a web panel provider to complete an online survey. The survey assessed grandparents’ physical activity-related beliefs (eg, perceived importance) and practices (eg, support and social control) and their grandchildren’s engagement in physical activity (unstructured, structured, and outdoor play) and screen-based activities while in grandparental care. Results: The importance of grandchildren’s physical activity was rated highly by grandparents. Grandparents’ support for their grandchildren’s physical activity was positively associated with their grandchildren’s engagement in structured physical activity, unstructured physical activity, and outdoor play. Negative social control was associated with greater engagement in screen-based activities. Other correlates of grandchildren’s physical activity and screen-based activities included grandparents’ own engagement in these activities. Conclusions: Findings highlight the importance of reinforcing the beliefs and practices that positively influence children’s movement behaviors and addressing those that have unintended consequences. Encouraging grandparents to support their grandchildren’s physical activity and discouraging forms of negative social control are likely to be important in efforts to promote physical activity in children.

Purpose: To investigate the training and development process of a multiple-Grand-Slam finalist. Methods: A mixed-methods case-study design was used to capture the quantitative and qualitative aspects related to the training and successful development process. We used a 3-step data-collection process and pragmatic analyses of (1) training history based on logs, plans, and questionnaires; (2) in-depth semistructured interviews with the player’s head coach/father, physical coach, and team administrator/mother; and (3) systematic quality assurance through negotiation among researchers and all key informants, including the player. Results: The player’s exceptional performance level was achieved by a progressive, nonlinear increase in annual training load during childhood and early youth, stabilizing at 800 sessions and 1250 to 1300 hours per year at the age of 19. The annual tennis-specific training plateaued at ∼750 hours from the age of 15, and 60 to 80 matches were played in most of the analyzed years. Point-play accounted for approximately 50% of the total amount of specific tennis training, clearly ahead of ground strokes (∼30%), serve/return (∼15%), and smash/volley (∼5%). Physical-conditioning hours increased 5-fold from 12 to 19 years, before stabilizing at ∼500 hours at senior age. Key success factors included the athlete’s multidimensional sports talent, discipline, and inner drive; a highly dedicated father and tennis-enthusiastic family; and strong support from a complementary and interdisciplinary performance team. Conclusion: This study provides novel information regarding the training and development process for a world-leading tennis player, providing a point of departure for the development of future talents.

The increasing trend of females participating in elite and historically male-dominated sports has also resulted in a rise in females performing dynamic warm-ups (DWs). DW is a widely used practice in hockey. However, there is scarce evidence describing how DWs impact subsequent anaerobic performance and whether this response differs between sexes. This study aimed to determine sex differences in anaerobic performance when preceded by a DW. Twenty National Collegiate Athletics Association Division-II hockey players (n = 20, 10 female) completed a Wingate Anaerobic Test (WAnT) preceded by a DW or no warm-up in a randomized, counterbalanced order and followed a crossover design. The DW was ∼8 min long and consisted of 13 movements that targeted prime muscles and joints involved in ice skating. The WAnT consisted of a 30-s, maximal effort sprint against 7.5% of the participant’s body mass performed on a cycle ergometer. Peak power output (PPO), relative peak power (RPP), mean anaerobic power (MP), and fatigue index (FI) evaluated anaerobic performance during the WAnT. There were no significant differences between male and female scores following DW. MP was significantly higher in males and females, but PPO, RPP, and FI were not when a DW preceded the WAnT. In both conditions, males had higher PPO and MP than females, while there were no sex differences in RPP and FI. In conclusion, performing a DW before a WAnT improved MP for females and males with no adverse effects on PPO, RPP, and FI. This study suggests that DW might benefit hockey players independently of sex.