Julie Taylor

Energy Expenditure During Physically Interactive Video Game Playing in Male College Students With Different Playing Experience

Objective: Researchers have yet to explore the effect of physically interactive video game playing on energy expenditure, despite its potential for meeting current minimal daily activity and energy expenditure recommendations. Participants and Methods: Nineteen male college students-12 experienced Dance Dance Revolution (DDR) players and 7 inexperienced players- completed maximal oxygen uptake assessments and a 30-minute DDR gaming session. The authors recorded heart rate (HR), rating of perceived exertion (RPE), respiratory exchange rate (RER), oxygen consumption (VO2), and total steps (TS30). Results: Experienced participants showed higher exercise HR, RPE, RER, VO2, total and relative energy expenditure, exercise intensity, TS30, and average steps per minute, and less time and steps to expend 150 kilocalories (p < .05). Conclusions: Participants with greater playing experience can work at higher intensities, promoting greater energy expenditure.

Repetitive Eccentric Strain at Long Muscle Length Evokes the Repeated Bout Effect

The repeated bout effect (RBE) is a phenomenon characterized by less delayed onset muscle soreness (DOMS) and torque deficit after the second of 2 separate eccentric exercise bouts. Previous investigators have reported that shifting of optimum angle after an initial bout of eccentric exercise mediates the RBE. We hypothesized that an RBE for elbow extensor exercise occurs after an initial bout performed at long (starting position of 508 to an end position of 1308) but not short (starting position of 08 to an end position of 808) muscle length because strain at long length evokes a shifting of the optimum angle to a longer length. Untrained women performed an initial bout at either long or short length (n = 9 per group) followed 1 week later by a repeated bout (RB) through the full ROM (0–1308). Extensor torque and optimum angle was evaluated before, immediately after, and 2 days after each bout. A mechanical transducer depressed on the triceps brachii quantified DOMS. Torque deficits were 3% and 7% after exercise at short vs. long length, respectively. Two days after the RB, torque deficit was 8% and 1% for those previously exercising at short vs. long length (group 3 bout, p < 0.05). Greater DOMS (N) was observed after exercise at long (16 ± 3) vs. short (23 ± 2) length; whereas greater DOMS occurred for the short-length (17 ± 2) vs. long (26 ± 3) group after the RB (group 3 bout, p < 0.05). Optimum angle shifted to a longer length after exercise at long (110 ± 48) vs. short (11 ± 38) length (group 3 bout, p < 0.05). After the RB, those exercising previously at short length experienced a shift of 115 ± 48 (main effect, p < 0.05). The findings of this study indicate that the repetitive strain at long but not short muscle length evokes both immediate and sustained shifts in optimum angle to longer lengths, and that this shifting mediates (r2 5 0.71) the RBE.

Validation of Hexoskin biometric shirt to COSMED K4 b2 metabolic unit in adults during trail running

Abstract Wearable biometric technology use has increased in recent years. The Hexoskin biometric shirt is a wearable technology that monitors heart rate (HR), ventilatory rate (VR), minute ventilation (VE), step count, and energy expenditure (EE). It is unknown whether the Hexoskin biometric shirt produces valid results in the field. Participants (N = 26) completed a self-paced 1.6 km trail run wearing the Hexoskin biometric shirt and the COSMED K4 b2 portable metabolic system. Data for HR, VR, and VE were analyzed in six one-minute increments occurring the first three minutes and the last three minutes of the run. Data for step count and energy expenditure were analyzed for the entire trail run. HR, VR, VE, step count, and EE data were analyzed using Pearson product-moment correlation with significance at p < .05. HR, VE, step count, and EE measures at all time points were not significantly correlated. VR measures at all time points were significantly correlated (p < .001). Our results indicate the Hexoskin biometric shirt provides valid measures of VR. For all other measures, the Hexoskin does not provide valid real time results.