, 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
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.
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.
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
Jianhua Wu, Toyin Ajisafe and Matthew Beerse
This study used both time and frequency domain analyses to investigate walking patterns with ankle load in children and adults. Twenty-two children aged 7–10 years and 20 young adults participated in this study. Three levels of ankle load were manipulated: no load, low load (2% of body mass on each side), and high load (4% of body mass on each side). An instrumented treadmill was used to register vertical ground reaction force (GRF) and spatiotemporal parameters, and peak vertical GRFs were determined. A frequency domain analysis was conducted on the vertical GRF data. Results demonstrate that, in the time domain, children showed adult-like spatiotemporal parameters and adult-like timing and magnitude of the 2 peak vertical GRFs under each load. In the frequency domain, children produced a lower power from the second harmonic than young adults, although both groups showed the highest power from this harmonic and increased this power with ankle load. It was concluded that children aged 7–10 years may start showing adult-like neuromuscular adaptations to increasing ankle load and display similar spatiotemporal control of foot falls and foot–floor kinetic interaction; however, a frequency domain analysis is effective in revealing different kinetic and neuromuscular characteristics between children and adults.
extension–flexion repetitions, 3 repeated countermovement jumps, 4 and treadmill running 5 fail to adequately reflect the activity profile of soccer match-play, and therefore, interpretation in relation to injury epidemiology and etiology is limited. In developing an experimental approach to the problem
Christopher K. Rhea and Matthew W. Wittstein
Much has been learned about the characteristics of gait in overground and treadmill walking. However, there are many contexts in which overground or treadmill walking might not be possible, such as in home-based physical therapy. In those cases, a surrogate task to index gait behavior would be a valuable tool. Thus, the purpose of this study was to evaluate the stride behavior characteristics of stationary stepping compared with treadmill walking. Healthy young adults (N = 10) preformed two 15-minute tasks: (1) treadmill walking and (2) stationary stepping. Several stride behavior characteristics were recorded, including the number of strides taken, minimum and maximum knee angle, stride interval mean, stride interval standard deviation, and detrended fluctuation analysis (DFA) alpha of the stride interval time series. The results showed that stride behavior was similar between tasks when examined at the group level. However, when individual level analyses were used to examine the reliability of each metric between tasks, poor reliability was observed in most metrics, indicating that stationary stepping may not be an appropriate surrogate task for overground or treadmill walking. These results are discussed in the context of a gait dynamics framework, with attention to task constraints that may have influenced the findings.
Erin M.R. Bigelow, Niell G. Elvin, Alex A. Elvin and Steven P. Arnoczky
To determine whether peak vertical and horizontal impact accelerations were different while running on a track or on a treadmill, 12 healthy subjects (average age 32.8 ± 9.8 y), were fitted with a novel, wireless accelerometer capable of recording triaxial acceleration over time. The accelerometer was attached to a custom-made acrylic plate and secured at the level of the L5 vertebra via a tight fitting triathlon belt. Each subject ran 4 miles on a synthetic, indoor track at a self-selected pace and accelerations were recorded on three perpendicular axes. Seven days later, the subjects ran 4 miles on a treadmill set at the individual runner’s average pace on the track and the peak vertical and horizontal impact magnitudes between the track and treadmill were compared. There was no difference (P = .52) in the average peak vertical impact accelerations between the track and treadmill over the 4 mile run. However, peak horizontal impact accelerations were greater (P = .0012) on the track when compared with the treadmill. This study demonstrated the feasibility for long-term impact accelerations monitoring using a novel wireless accelerometer.