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Fábio J. Lanferdini, Rodrigo R. Bini, Bruno M. Baroni, Kelli D. Klein, Felipe P. Carpes and Marco A. Vaz

incremental test and a familiarization with the time-to-exhaustion test were performed. In the other sessions (days 2–5), cyclists performed time-to-exhaustion tests after application of different doses of LLLT (135, 270, or 405 J/thigh) or placebo at the knee-extensor muscles, in a randomized order (Figure

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Scott E. Crouter, Paul R. Hibbing and Samuel R. LaMunion

/sec, the AG assumes the person is standing and inclination angle is ignored. In contrast, the AP is not as susceptible to confusing sitting and standing, because it is worn on the thigh, meaning the device will experience a change in incline of about 90 degrees between sitting and standing. However, the AP

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Alan K. Bourke, Espen A. F. Ihlen and Jorunn L. Helbostad

-third of the way down on the anterior aspect of the left thigh using a hydrogel patch (PALStickies ™ ). Activity classification, postural transfer detection, and steps detected by the activPAL3 were compared directly against video observations. Participants were recorded in two scenarios. The first was an

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Declan J. Ryan, Jorgen A. Wullems, Georgina K. Stebbings, Christopher I. Morse, Claire E. Stewart and Gladys L. Onambele-Pearson

affect CVD). Participants were fitted with a commercially available, dominant leg, thigh-mounted (anterior aspect, at 50% of greater trochanter to femoral condyle distance) triaxial accelerometer (GENEA, GENEActiv Original; Activinsights Ltd, Kimbolton, UK) using a waterproof adhesive patch (Tegaderm

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M. Monda, A. Goldberg, P. Smitham, M. Thornton and I. McCarthy

To study mobility in older populations it can be advantageous to use portable gait analysis systems, such as inertial measurement units (IMUs), which can be used in the community. To define a normal range, 136 active subjects were recruited with an age range of 18 to 97. Four IMUs were attached to the subjects, one on each thigh and shank. Subjects were asked to walk 10 m at their own self-selected speed. The ranges of motion of thigh, shank, and knee in both swing and stance phase were calculated, in addition to stride duration. Thigh, shank, and knee range of movement in swing and stance were significantly different only in the > 80 age group. Regressions of angle against age showed a cubic relationship. Stride duration showed a weak linear relationship with age, increasing by approximately 0.1% per year.

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Hyunjae Jeon, Melanie L. McGrath, Neal Grandgenett and Adam B. Rosen

management of symptoms and severity of PT. In addition, the current study may provide some insight for clinicians to more effectively manage the symptoms of those with more severe bouts of PT. Based on the results, during rehabilitation for PT, clinicians should target thigh musculature strengthening and

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Sara L. Arena, Kelsey McLaughlin, Anh-Dung Nguyen, James M. Smoliga and Kevin R. Ford

Athletic individuals may differ in body segment inertial parameter (BSIP) estimates due to differences in body composition, and this may influence calculation of joint kinetics. The purposes of this study were to (1) compare BSIPs predicted by the method introduced by de Leva1 with DXA-derived BSIPs in collegiate female soccer players, and (2) examine the effects of these BSIP estimation methods on joint moment and power calculations during a drop vertical jump (DVJ). Twenty female NCAA Division I soccer players were recruited. BSIPs of the shank and thigh (mass, COM location, and radius of gyration) were determined using de Leva’s method and analysis of whole-body DXA scans. These estimates were used to determine peak knee joint moments and power during the DVJ. Compared with DXA, de Leva’s method located the COM more distally in the shank (P = .008) and more proximally in the thigh (P < .001), and the radius of gyration of the thigh to be further from the thigh COM (P < .001). All knee joint moment and power measures were similar between methods. These findings suggest that BSIP estimation may vary between methods, but the impact on joint moment calculations during a dynamic task is negligible.

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Melissa M.B. Morrow, Wendy J. Hurd, Emma Fortune, Vipul Lugade and Kenton R. Kaufman

This study aimed to define accelerations measured at the waist and lower extremities over a range of gait velocities to provide reference data for choosing the appropriate accelerometer for field-based human activity monitoring studies. Accelerations were measured with a custom activity monitor (± 16g) at the waist, thighs, and ankles in 11 participants over a range of gait velocities from slow walking to running speeds. The cumulative frequencies and peak accelerations were determined. Cumulative acceleration amplitudes for the waist, thighs, and ankles during gait velocities up to 4.8 m/s were within the standard commercial g-range (± 6g) in 99.8%, 99.0%, and 96.5% of the data, respectively. Conversely, peak acceleration amplitudes exceeding the limits of many commercially available activity monitors were observed at the waist, thighs, and ankles, with the highest peaks at the ankles, as expected. At the thighs, and more so at the ankles, nearly 50% of the peak accelerations would not be detected when the gait velocity exceeds a walking velocity. Activity monitor choice is application specific, and investigators should be aware that when measuring high-intensity gait velocity activities with commercial units that impose a ceiling at ± 6g, peak accelerations may not be measured.

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Christine D. Pollard, Bryan C. Heiderscheit, Richard E.A. van Emmerik and Joseph Hamill

The purpose of this study was to determine if gender differences exist in the variability of various lower extremity (LE) segment and joint couplings during an unanticipated cutting maneuver. 3-D kinematics were collected on 24 college soccer players (12 M, 12 F) while each performed the cutting maneuver. The following intralimb couplings were studied: thigh rotation (rot)/leg rot; thigh abduction-adduction/leg abd-add; hip abd-add/knee rot; hip rot/knee abd-add; knee flexion-extension/knee rot; knee flx-ext/hip rot. A vector-coding technique applied to angle-angle plots was used to quantify the coordination of each coupling. The average between-trial standard deviation of the coordination pattern during the initial 40% of stance was used to indicate the coordination variability. One-tailed t-tests were used to determine differences between genders in coordination variability for each coupling. Women had decreased variability in four couplings: 32% less thigh rot/leg rot variability; 40% less thigh abd-add/leg abd-add variability; 46% less knee flx-ext/knee rot variability; and 44% less knee flx-ext/hip rot variability. These gender differences in LE coordination variability may be associated with the increased incidence of ACL injury in women. If women exhibit less flexible coordination patterns during competition, they may be less able to adapt to the environmental perturbations experienced during sports. These perturbations applied to a less flexible system may result in ligament injury.

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David G. Kerwin, Maurice R. Yeadon and Sung-Cheol Lee

An 11-segment three-dimensional simulation model was used to modify the body configurations of eight gymnasts performing multiple somersault dismounts during the Men’s High Bar competition in the 1988 Seoul Olympic Games. Four layout double somersault performances were modified to change a characteristic backward arch to a straight body position. This modification reduced the somersault rotation by 0.03 to 0.10 somersaults. Four tucked triple somersault performances were modified so that the thigh abduction angle was reduced to zero. This modification resulted in underrotations ranging from 0.01 to 0.34 somersaults depending on the amount of thigh abduction in the original movement. The additional angular momentum needed for successful completion of the modified movements was small in general and in no case greater than 13%.