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Study design: This is an experimental design. Objectives: This study examined the association between rates of energy expenditure (that is, oxygen consumption (VO 2 )) and accelerometer counts (that is, vector magnitude (VM)) across a range of speeds during manual wheelchair propulsion on a motor-driven treadmill. Such an association allows for the generation of cutoff points for quantifying the time spent in moderate-to-vigorous physical activity (MVPA) during manual wheelchair propulsion. Setting: The study was conducted in the University Laboratory. Methods: Twenty-four manual wheelchair users completed a 6-min period of seated rest and three 6-min periods of manual wheelchair propulsion on a motor-driven wheelchair treadmill. The 6-min periods of wheelchair propulsion corresponded with three treadmill speeds (1.5, 3.0 and 4.5 mph) that elicited a range of physical activity intensities. Participants wore a portable metabolic unit and accelerometers on both wrists. Primary outcome measures included steady-state VO 2 and VM, and the strength of association between VO 2 and VM was based on the multiple correlation and squared multiple correlation coefficients from linear regression analyses. Results: Strong linear associations were established between VO 2 and VM for the left (R = 0.93 ± 0.44; R 2 = 0.87 ± 0.19), right (R = 0.95 ± 0.37; R 2 = 0.90 ± 0.14) and combined (R = 0.94 ± 0.38; R 2 = 0.88 ± 0.15) accelerometers. The linear relationship between VO 2 and VM for the left, right and combined wrists yielded cutoff points for MVPA of 3659 ± 1302, 3630 ± 1403 and 3644 ± 1339 counts min − 1 , respectively. Conclusion: We provide cutoff points based on the linear association between energy expenditure and accelerometer counts for estimating time spent in MVPA during manual wheelchair propulsion using wrist-worn accelerometry. The similarity across wrist location permits flexibility in selecting a location for wrist accelerometry placement.

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This study aimed to examine the level of shooting accuracy demonstrated by law enforcement recruits upon completion of their law enforcement firearms training in comparison with novice shooters. One hundred and ninety-five male and 52 female law enforcement recruits volunteered. Participants were separated by firearms experience into the following groups: expert (completed law enforcement firearms course, n ¼ 83), intermediate (recreational experience, n ¼ 71) and novice (minimal/no experience, n ¼ 93). All subjects were tested for accuracy at target locations from 3 to 75 ft. For all locations, no difference was found in accuracy between expert and intermediate groups (p > 0.30). Experts and intermediates had better results than novices on all locations (p < 0.05) except from 3 to 15 ft. Alarmingly, experts were only 10% more accurate than novices between 3 and 15 ft. Finally, novices and intermediate shooters were more likely to hit head locations from 3 ft (57%), whereas experts mainly hit the body location (78%). The results of this study indicate that officers had no advantage over intermediate shooters and a small advantage over novices.

Our purpose was to examine the influence of glove type on kinetic and spatiotemporal parameters at the handrim in elite wheelchair racers. Elite wheelchair racers (n=9) propelled on a dynamometer in their own racing chairs with a force and moment sensing wheel attached. Racers propelled at 3 steady state speeds (5.36, 6.26 & 7.60 m/s) and performed one maximal effort sprint with 2 different glove types (soft & solid). Peak resultant force, peak torque, impulse, contact angle, braking torque, push time, velocity, and stroke frequency were recorded for steady state and sprint conditions. Multiple nonparametric Wilcoxon matched pair's tests were used to detect differences between glove types, while effect sizes were calculated based on Cohen's d. During steady state trials, racers propelled faster, using more strokes and larger contact angle, while applying less impulse with solid gloves compared to soft gloves. During the sprint condition, racers achieved greater top end velocities, applying larger peak force, with less braking torque with solid gloves compared to soft gloves. Use of solid gloves may provide some performance benefits to wheelchair racers during steady state and top end velocity conditions.