, some experiments have modified existing treadmills either by attaching discrete obstacles or even by creating a continuous balance beam using a set of narrow blocks. 13 , 14 However, discrete perturbations on a treadmill do not allow for measurements of steady-state dynamics and are not suitable for
Alexandra S. Voloshina and Daniel P. Ferris
Jaimie A. Roper, Ryan T. Roemmich, Mark D. Tillman, Matthew J. Terza and Chris J. Hass
may thus also affect the control of frontal plane motion. 7 However, it is unknown how frontal plane gait mechanics change when the speeds of each leg are manipulated independently rather than simultaneously. Split-belt treadmill walking is a rehabilitation intervention that allows researchers to
Brandon R. Rigby, Ronald W. Davis, Marco A. Avalos, Nicholas A. Levine, Kevin A. Becker and David L. Nichols
observed increases in cardiometabolic responses ( Protas, Stanley, Jankovic, & MacNeill, 1996 ; Stanley, Protas, & Jankovic, 1999 ). To improve cardiorespiratory fitness and gait dysfunction, aerobic exercise on a motorized treadmill has been shown to be an effective intervention in those diagnosed with
Adam M. Fullenkamp, Danilo V. Tolusso, C. Matthew Laurent, Brian M. Campbell and Andrea E. Cripps
The use of traditional motorized treadmills (MTs) is an established approach for physiological conditioning, sport-specific training, gait retraining, and the study of human locomotion. In particular, MTs offer the convenience of spatial control, enabling locomotion in an environment that is
Joanna Scurr, Jennifer White and Wendy Hedger
This study aimed to assess the trajectory of breast displacement in 3 dimensions during walking and running gait, as this may improve bra design and has yet to be reported. Fifteen D-cup participants had reflective markers attached to their nipples and trunk to monitor absolute and relative breast displacement during treadmill walking (5 kph) and running (10 kph). During the gait cycle, the breast followed a figure-of-eight pattern with four movement phases. Despite a time lag in resultant breast displacement compared with the trunk, similar values of breast displacement were identified across each of the four phases. Fifty-six percent of overall breast movement was vertical, suggesting that 3-D assessment and the elimination of trunk movement in 6 degrees of freedom are essential to accurately report breast displacement during the gait cycle.
Monika Lohkamp, Simon Craven, Colin Walker-Johnson and Matt Greig
Postural stability diminishes with longer activity, which may increase the risk of injury. Tape can increase stability, but this effect diminishes after exercise.
To investigate the influence of ankle taping on postural stability during soccer-specific activity.
10 male, injury-free, semiprofessional soccer players.
A 45-min treadmill protocol replicating the activity profile of soccer match play—with and without ankle tape. Postural stability was assessed every 7.5 min, requiring response to sudden ankle plantar flexion and inversion during single-leg stance.
Main Outcome Measure:
Reaction time to perturbation and center- of-gravity (CoG) displacement.
Reaction time was significantly longer (P < .05) with longer exercise for both movements and conditions. No significant effect was evident in CoG displacement. For both outcome measures a nonsignificant benefit of taping was observed during the first 22.5 min of activity.
Prolonged exposure to soccer-specific activity negates any beneficial effect of taping in improving postural stability.
Rebecca J. Bedard, Kyung-Min Kim, Terry L. Grindstaff and Joseph M. Hart
To compare active hamstring stiffness in female subjects with and without a history of low back pain (LBP) after a standardized 20-min aerobic-exercise session.
12 women with a history of recurrent episodes of LBP (age = 22.4 ± 2.1 y, mass = 67.1 ± 11.8 kg, height = 167.9 ± 8 cm) and 12 matched healthy women (age = 21.7 ± 1.7 y, mass = 61.4 ± 8.8 kg, height = 165.6 ± 7.3 cm). LBP subjects reported an average 6.5 ± 4.7 on the Oswestry Disability Index.
Participants walked at a self-selected speed (minimum 3.0 miles/h) for 20 min. The treadmill incline was raised 1% grade per minute for the first 15 min. During the last 5 min, participants adjusted the incline of the treadmill so they would maintain a moderate level of perceived exertion through the end of the exercise protocol.
Main Outcome Measures:
During session 1, active hamstring stiffness, hamstring and quadriceps isometric strength, and concurrently collected electromyographic activity were recorded before and immediately after the exercise protocol. For session 2, subjects returned 48–72 h after exercise for repeat measure of active hamstring stiffness.
Hamstring active stiffness (Nm/rad) taken immediately postexercise was not significantly different between groups. However, individuals with a history of recurrent LBP episodes presented significantly increased hamstring stiffness 48–72 h postexercise compared with controls. For other outcomes, there was no group difference.
Women with a history of recurrent LBP episodes presented greater active hamstring stiffness 48–72 h after aerobic exercise.
Adam C. Clansey, Mark J. Lake, Eric S. Wallace, Tom Feehally and Michael Hanlon
The purpose of this study was to investigate the effects of prolonged high-intensity running on impact accelerations in trained runners. Thirteen male distance runners completed two 20-minute treadmill runs at speeds corresponding to 95% of onset of blood lactate accumulation. Leg and head accelerations were collected for 20 s every fourth minute. Rating of perceived exertion (RPE) scores were recorded during the third and last minute of each run. RPE responses increased (P < .001) from the start (11.8 ± 0.9, moderate intensity) of the first run to the end (17.7 ± 1.5, very hard) of the second run. Runners maintained their leg impact acceleration, impact attenuation, stride length, and stride frequency characteristics with prolonged run duration. However, a small (0.11–0.14g) but significant increase (P < .001) in head impact accelerations were observed at the end of both first and second runs. It was concluded that trained runners are able to control leg impact accelerations during sustained high-intensity running. Alongside the substantial increases in perceived exertion levels, running mechanics and frequency domain impact attenuation levels remained constant. This suggests that the present trained runners are able to cope from a mechanical perspective despite an increased physiological demand.
Ben J. Lee and Charles Douglas Thake
). 6 , 8 – 10 For example, walking with 75% BWS reduced energy expenditure by 45% compared with a nonsupported walk. 8 However, the metabolic cost of running at increasing levels of BWS can be offset by increasing treadmill speed. 6 , 8 , 10 Indeed, both submaximal and maximal V ˙ O 2 achieved
Daniel E. Lidstone, Justin A. Stewart, Reed Gurchiek, Alan R. Needle, Herman van Werkhoven and Jeffrey M. McBride
standard Bruce protocol was used to test V ˙ O 2 max in our participants. Subjects performed the protocol to volitional fatigue on a motor driven treadmill (Full Vision Inc. Trackmaster TMX425C, Newton, KS, USA). The first stage of the test is 2.7 km·h –1 at a 10% gradient for 3 minutes. At 3-minute