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721.
The purpose of this study was to examine the validity of a highly popular pedometer application (Samsung Health). Sixteen adults (28.8 ± 8.9 years of age) wore two Samsung smartphone models, Samsung Galaxy Core Prime (SGCP) and Samsung Galaxy S4 (SGS4), at three body locations (waist, arm, and hand) while walking and running over a 50-m test. All trials were recorded using a video as a gold standard measure of step counts. Results indicated that the validity of Samsung Health varied depending on the smartphone model, its body location, and the type of gait (walking and running). Samsung Health showed acceptable validity when the SGCP was located on the hand (Bias = ?8.3%; RMSE = 5.6), and especially on the arm (Bias = ?7.2%; RMSE = 4.9) while running, and when the SGS4 was located on the arm (Bias = ?7.5%; RMSE = 5.4), and especially on the waist (Bias = 5.4%; RMSE = 3.7) while walking. Samsung Health only showed good validity when the SGS4 was located on the arm (Bias = 2.9%; RMSE = 3.6), and especially on the hand (Bias = 0.5%; RMSE = 2.5) while running. This application showed unacceptable validity in the remaining options.  相似文献   
722.
This study analysed the acute mechanical and metabolic responses to a sprint training session focused on maintaining maximal speed until a given speed loss was reached. Nine male high-level sprinters performed 60 m running sprints up to a 3% in speed loss with 6 min rests between sets. Mechanical responses (countermovement jump (CMJ) height and speed loss) and metabolic responses (blood lactate and ammonia concentrations) were measured pre-exercise and after each set was performed. Jump height loss showed almost perfect relationships with both lactate (r = 0.91) and ammonia (r = 0.91) concentrations. In addition, nearly perfect relationships were observed for each athlete between CMJ height loss and lactate (r = 0.93–0.99) and ammonia (r = 0.94–0.99). Very large correlations were found between speed loss and lactate (r = 0.83), and ammonia (r = 0.86) concentrations. Furthermore, close relationships were observed for each athlete between speed loss and lactate (r = 0.86–0.99), and ammonia (r = 0.88–0.98). These results suggest that the CMJ test may allow more accurate setting of training loads in sprint training sessions, by using an individualised sprint dose based on mechanical and physiological responses rather than a standard fixed number of sprints for all athletes.  相似文献   
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724.
To ensure that elite adolescent athletes meet their unique training, growth and maturation demands, it is imperative to have access to valid measures of energy intake. Contemporary methods demand close attention-to-detail, meaning that athletes often do not fully adhere to real-time protocols. This study represents the first investigation of a real-time dietary assessment designed using a comprehensive behaviour change framework (COM-B). In a crossover design, 12 elite adolescent male rugby players recorded their energy intake via an estimated food diary (est-FD) and photography-based mobile assessment (‘Snap-n-Send’), combined with a 24-h dietary recall interview. Two 4-day assessment periods were divided into three separate recording environments: 96?h free-living and researcher-observed; 72?h free-living and 10?h researcher-observed. Assessment periods were one month apart. All foods and beverages were provided and weighed by the research team to quantify actual intakes. ‘Snap-n-Send’ reported a small mean bias for under-reporting across 96?h (?0.75?MJ?day?1; 95% confidence interval [CI] for bias?=??5.7% to ?2.2%, p?<?.001), 72?h (?0.76?MJ?day?1; 95% CI for bias?=??5.6% to ?2.1%, p?=?.004) and 10?h (?0.72?MJ?day?1; 95% CI for bias?=??8.1% to ?0.1%; p?=?.067) environments. The est-FD reported a moderate mean bias for under-reporting across 96?h (?2.89?MJ?day?1; 95% CI for bias?=??17.9% to ?10.2%; p?<?.001), 72?h (?2.88?MJ?day?1; 95% CI for bias?=??17.9% to ?10.1%; p?<?.001) and 10?h (?2.52?MJ?day?1;?26.1% to ?5.3%; p?=?.023) environments. Results evidence the ability of ‘Snap-n-Send’ to accurately assess the diet of elite adolescent athletes, signalling the exciting promise of this comprehensive and theoretical behavioural approach within valid dietary assessment.  相似文献   
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