This study supports the hypothesis that RPE increases similarly in relation to relative distance, regardless of the distance performed, and it suggests that the perception of effort has scalar properties.

Background: The pattern of energy expenditure during sustained high-intensity exercise is influenced by several variables. Data from athletic populations suggest that a pre-exercise conceptual model, or template, is a central variable relative to controlling energy expenditure. Aims: The aim of this study was to make systematic observations regarding how the performance template develops in fit individuals who have limited specific experience with sustained high-intensity exercise (eg, time trials). Methods: The study was conducted in four parts and involved measuring performance (time and power output) during: (A) six 3 km cycle time trials, (B) three 2 km rowing time trials, (C) four 2 km rowing time trials with a training period between trials 2 and 3, and (D) three 10 km cycle time trials. All time trials were self-paced with feedback to the subjects regarding previous performances and momentary pace. Results: In all four series of time trials there was a progressive pattern of improved performance averaging 6% over the first three trials and 10% over six trials. In all studies improvement was associated with increased power output during the early and middle portions of the time trial and a progressively greater terminal rating of perceived exertion. Despite the change in the pattern of energy expenditure, the subjects did not achieve the pattern usually displayed by athletes during comparable events. Conclusions: This study concludes that the pattern of learning the performance template is primarily related to increased confidence that the trial can be completed without unreasonable levels of exertion or injury, but that the process takes more than six trials to be complete.

The concept of VO(2)max has been a defining paradigm in exercise physiology for >75 years. Within the last decade, this concept has been both challenged and defended. The purpose of this study was to test the concept of VO(2)max by comparing VO(2) during a second exercise bout following a preliminary maximal effort exercise bout. The study had two parts. In Study #1, physically active non-athletes performed incremental cycle exercise. After 1-min recovery, a second bout was performed at a higher power output. In Study #2, competitive runners performed incremental treadmill exercise and, after 3-min recovery, a second bout at a higher speed. In Study #1 the highest VO(2) (bout 1 vs. bout 2) was not significantly different (3.95 +/- 0.75 vs. 4.06 +/- 0.75 l min(-1)). Maximal heart rate was not different (179 +/- 14 vs. 180 +/- 13 bpm) although maximal V(E) was higher in the second bout (141 +/- 36 vs. 151 +/- 34 l min(-1)). In Study #2 the highest VO(2) (bout 1 vs. bout 2) was not significantly different (4.09 +/- 0.97 vs. 4.03 +/- 1.16 l min(-1)), nor was maximal heart rate (184 + 6 vs. 181 +/- 10 bpm) or maximal V(E) (126 +/- 29 vs. 126 +/- 34 l min(-1)). The results support the concept that the highest VO(2) during a maximal incremental exercise bout is unlikely to change during a subsequent exercise bout, despite higher muscular power output. As such, the results support the "classical" view of VO(2)max.

During the last decade, there has been active interest in indoor cycling (e.g., spinning) as a method of choreographed group exercise. Recent studies have suggested that exercise intensity during indoor cycling may be quite high and may transiently exceed Vo2max. This study sought to confirm these findings, as the apparent high intensity of indoor cycling has implications for both the efficacy and the risk of indoor cycling as an exercise method. Twenty healthy female students performed an incremental exercise test to define Vo2max and performed 2 videotaped indoor exercise classes lasting 45 minutes and 35 minutes. Vo2, heart rate (HR), and rating of perceived exertion (RPE) were measured during the indoor cycling classes, with Vo2 data integrated in 30-second intervals. The mean %Vo2max during the indoor cycling classes was modest (74 +/- 14% Vo2max and 66 +/- 14%Vo2max, respectively). However, 52% and 35% of the time during the 45- and 35-minute classes was spent at intensities greater than the ventilatory threshold (VT). The HR response indicated that 35% and 38% of the session time was above the HR associated with VT. In 10 of the 40 exercise sessions, there were segments in which the momentary Vo2 exceeded Vo2max observed during incremental testing, and the cumulative time with exercise intensity greater than Vo2max ranged from 0.5 to 14.0 minutes. It can be concluded that although the intensity of indoor cycling in healthy, physically active women is moderate, there are frequent observations of transient values of Vo2 exceeding Vo2max, and a substantial portion of the exercise bouts at intensities greater than VT. As such, the data suggest that indoor cycling must be considered a high-intensity exercise mode of exercise training, which has implications for both efficacy and risk.

The physical characteristics and performances of female collegiate rowers were examined from two perspectives: level (novice, varsity) and years of participation (0, 1, 2, 3) in collegiate rowing. The participants were 90 female collegiate rowers from three US Division I university teams, of the National Collegiate Athletic Association (NCAA). Height, body mass, sitting height, arm span, skinfolds, limb circumferences, and skeletal breadths were measured. Leg length was estimated and Heath-Carter anthropometric somatotypes were calculated. Performance measures included lower-back flexibility, vertical jump, and 2-km time on a rowing ergometer. Descriptive statistics were calculated for the total sample and by level and years of experience. Multivariate analysis of variance and a Bonferroni-adjusted alpha level (P < 0.05) were used to test differences. Varsity rowers had significantly more rowing experience ( approximately 0.5 years) before college, higher vertical jumps ( approximately 3 cm), faster 2-km times ( approximately 25 s), and lower endomorphic characteristics than novice rowers. Anthropometric and performance differences among rowers by years of experience were negligible with the exception of slower 2-km times ( approximately 32 s) in rowers with no collegiate experience than rowers with collegiate experience. In conclusion, collegiate rowers differ to some extent in physical and performance characteristics by level and experience.

Overall, rural child care centers in Western North Carolina were meeting standards, they were still able to strengthen policies and practices by following NAP SACC. This was especially true for centers unaffiliated with schools. Continued financial support may assist centers in sustaining increased physical activity in children.

Smartphone use among college students is prevalent across the world. Recently, research has begun to investigate the relationship between smartphone use and physical activity. This study examined the amount of time spent using a smartphone and the physical activity (PA) levels among college students majoring in health science-related disciplines in the United States (US) and Thailand. Using convenience sampling, college students in the US (n = 242) and Thailand (n = 194) completed an online survey, in Fall 2016, assessing smartphone usage and PA. Data were analyzed using chi-square tests and two-way ANOVA (p < 0.05). US students reported more days per week ( U = 15,150.0 , p = 0.00 , r = 0.33 ) and greater duration of PA ( U = 11,234.0 , p = 0.00 , r = 0.33 ) than Thai students while Thai students used smartphones more per day than US students ( U = 13,137.5 , p = 0.00 , r = 0.40 ). No difference existed for years of smartphone use ( U = 22,207.0 , p = 0.27 ). Greater smartphone use per day inversely related to days per week of engaging in PA among Thai students ( X 2 ( 3 ) = 10.55 , p = 0.01 , ε 2 = 0.06 ), but not among US students ( X 2 ( 3 ) = 2.39 , p = 0.50 ). The high smartphone use among college students, especially in Thailand, may be a barrier to PA as well as a strategy for PA promotion in higher education settings. Research should examine the best techniques for smartphone application development to promote PA in college settings.

Ankle sprains and their common sequalae are thought to negatively affect physical activity levels and health-related quality of life among active populations, but limited evidence has described this among younger populations. This study aimed to determine the prevalence rate of ankle sprain and chronic ankle instability among rural adolescents and subsequently compare their physical activity levels based on ankle injury status. The study was conducted in a rural high school in North Carolina. High school students completed an online survey that assessed ankle injury history, perception of ankle instability and function, and physical activity. Respondents were categorized into one of four groups based on ankle injury history and complaints of instability: 1) uninjured (no history of injury); 2) unstable (history of injury >1 year and recurrent instability); 3) copers (history of injury >1 year and no recurrent instability); and 4) potentially unstable (injury within the past year). Frequency of physical activity was compared across groups using analysis of variance, Kruskall-Wallis test (α = 0.05), and responses to activity type were assessed using chi-square. Physical activity was found to differ significantly between the four groups with unstable respondents reporting more physical activity than uninjured respondents (unstable = 4706.05 ± 4610.56 MET-minutes/week; uninjured = 2592.93 ± 2946.02 MET-minutes/week). No differences were found between other groups. Despite injury history and sensations of instability, respondents with chronic ankle instability reported greater physical activity levels than uninjured participants. As this is contrary to pre-existing hypotheses, it is possible that continued physical activity after injury among adolescents may contribute to deleterious outcomes such as increased frequency of chronic instability.