You are looking at 61 - 70 of 16,438 items for :

  • Sport and Exercise Science/Kinesiology x
Clear All
Restricted access

Dechristian França Barbieri, Luiz Augusto Brusaca, Svend Erik Mathiassen and Ana Beatriz Oliveira

Background: Sit–stand desks have been suggested as an initiative to increase posture variation among office workers. However, there is limited evidence of what would be preferable combinations of time sitting and standing. The aim of this study was to determine and compare perceived pleasantness, acceptability, pain, and fatigue for 5 time patterns of sitting and standing at a sit–stand desk. Methods: Thirty postgraduate students were equally divided into a normal-weight (mean body mass index 22.8 kg/m2) and an overweight/obese (mean body mass index 28.1 kg/m2) group. They performed 3 hours of computer work at a sit–stand desk on 5 different days, each day with a different time pattern (A: 60-min sit/0-min stand; B: 50/10; C: 40/20; D: 30/30; E: 20/40). Pleasantness, acceptability, pain, and fatigue ratings were obtained at the beginning and at the end of the 3-hour period. Results: High ratings of pleasantness were observed for time patterns B, C, and D in both groups. All participants rated acceptability to be good for time patterns A to D. A minor increase in perceived fatigue and pain was observed in time pattern E. Conclusion: For new sit–stand desk users, regardless of body mass index, 10 to 30 minutes of standing per hour appears to be an amenable time pattern.

Restricted access

Alessandra Buja, Andrea Rabensteiner, Milena Sperotto, Giulia Grotto, Chiara Bertoncello, Silvia Cocchio, Tatjana Baldovin, Paolo Contu, Chiara Lorini and Vincenzo Baldo

Background: The importance of health literacy (HL) in health promotion is increasingly clear and acknowledged globally, especially when addressing noncommunicable diseases. This paper aimed to collect and summarize all current data from observational studies generating evidence of the association between HL and physical activity (PA) and to analyze intervention studies on the promotion of PA to ascertain whether HL moderates the efficacy of such intervention. Methods: A comprehensive systematic literature search of observational studies investigating the association between HL and PA was performed. Intervention studies on the promotion of PA that also measured the HL levels of participants and its effect on the outcome of the intervention were also identified. Results: Of the 22 studies included in this review, 18 found a significant positive association between high HL and high levels of PA. The only intervention study among them indicated that HL was not a significant moderator of the intervention’s effectiveness. Conclusion: HL can enable individuals to make deliberate choices about their PA and thus contribute to preventing many chronic noncommunicable diseases. That said, low levels of HL do not seem to influence the efficacy of health promotion interventions.

Open access

Sophia Nimphius and Matthew J. Jordan

Restricted access

Steve H. Faulkner and Philippa Jobling

Purpose: Cycling time trials (TTs) are characterized by riders’ adopting aerodynamic positions to lessen the impact of aerodynamic drag on velocity. The optimal performance requirements for TTs likely exist on a continuum of rider aerodynamics versus physiological optimization, yet there is little empirical evidence to inform riders and coaches. The aim of the present study was to investigate the relationship between aerodynamic optimization, energy expenditure, heat production, and performance. Methods: Eleven trained cyclists completed 5 submaximal exercise tests followed by a TT. Trials were completed at hip angles of 12° (more horizontal), 16°, 20°, 24° (more vertical), and their self-selected control position. Results: The largest decrease in power output at anaerobic threshold compared with control occurred at 12° (−16 [20] W, P = .03; effect size [ES] = 0.8). There was a linear relationship between upper-body position and heat production (R 2 = .414, P = .04) but no change in mean body temperature, suggesting that, as upper-body position and hip angle increase, convective and evaporative cooling also rise. The highest aerodynamic–physiological economy occurred at 12° (384 [53] W·C d A −1·L−1·min−1, ES = 0.4), and the lowest occurred at 24° (338 [28] W·C d A −1·L−1·min−1, ES = 0.7), versus control (367 [41] W·C d A −1·L−1·min−1). Conclusion: These data suggest that the physiological cost of reducing hip angle is outweighed by the aerodynamic benefit and that riders should favor aerodynamic optimization for shorter TT events. The impact on thermoregulation and performance in the field requires further investigation.

Restricted access

Derrick D. Brown, Jurjen Bosga and Ruud G.J. Meulenbroek

This study investigated effects of mirror and metronome use on spontaneous upper body movements by 10 preprofessional dancers in a motor task in which maximally diverse upper body movement patterns were targeted. Hand and trunk accelerations were digitally recorded utilizing accelerometers and analyzed using polar frequency distributions of the realized acceleration directions and sample entropy of the acceleration time. Acceleration directions were more variably used by the arms than by the torso, particularly so when participants monitored their performance via a mirror. Metronome use hardly affected the predictability of the acceleration time series. The findings underscore the intrinsic limitations that people experience when being asked to move randomly and reveal moderate effects of visual and acoustic constraints on doing so in dance.