Article

Averaged EMG profiles in jogging and running at different speeds

Center for Human Movement Sciences, University of Groningen, 9700 AD Groningen, The Netherlands.
Gait & Posture (Impact Factor: 2.75). 05/2007; 25(4):604-14. DOI: 10.1016/j.gaitpost.2006.06.013
Source: PubMed

ABSTRACT

EMGs were collected from 14 muscles with surface electrodes in 10 subjects walking 1.25-2.25 ms(-1) and running 1.25-4.5 ms(-1). The EMGs were rectified, interpolated in 100% of the stride, and averaged over all subjects to give an average profile. In running, these profiles could be decomposed into 10 basic patterns, 8 of which represented only a single burst. Muscles could be divided into a quadriceps, hamstrings, calf and gluteal group, the profiles of which were composed of the same basic patterns. The amplitude of some bursts was constant, but other ones varied with running speed. This speed dependency was generally different between muscles of the same group. Many muscles show a similar profile in running as in walking. The most notable exception is the calf group, which shows activation in early stance (86-125%), together with quadriceps, instead of in late stance (26-55%) as in walking. This is also visible in low-speed running, 'jogging', where stance extends to 46% or 57%, instead of 30-37% as in normal running. Jogging shows some additional differences with normal running, related to this prolonged stance phase.

Full-text

Available from: At L Hof
    • "We suggest the pattern of transverse plane pelvic motion during running is a secondary consequence of gluteus maximus activity. This muscle is active for most of stance phase (Gazendam & Hof, 2007; Willson et al., 2012) and functions primarily to extend the hip. However, gluteus maximus will also act to externally rotate the hip (Delp, Hess, Hungerford, & Jones, 1999) or, equivalently, rotate the pelvis away from the stance limb. "
    [Show abstract] [Hide abstract] ABSTRACT: Previous research into running has demonstrated consistent patterns in pelvic, lumbar and thoracic motions between different human runners. However, to date, there has been limited attempt to explain why observed coordination patterns emerge and how they may relate to centre of mass (CoM) motion. In this study, kinematic data were collected from the thorax, lumbar spine, pelvis and lower limbs during over ground running in n=28 participants. These data was subsequently used to develop a theoretical understanding of the coordination of the spine and pelvis in all three body planes during the stance phase of running. In the sagittal plane, there appeared to be an antiphase coordinate pattern which may function to increase femoral inclination at toe off whilst minimising anterior-posterior accelerations of the CoM. In the medio-lateral direction, CoM motion appears to facilitate transition to the contralateral foot. However, an antiphase coordination pattern was also observed, most likely to minimise unnecessary accelerations of the CoM. In the transverse plane, motion of the pelvis was observed to lag slightly behind that of the thorax. However, it is possible that the close coupling between these two segments facilitates the thoracic rotation required to passively drive arm motion. This is the first study to provide a full biomechanical rationale for the coordination of the spine and pelvis during human running. This insight should help clinicians develop an improved understanding of how spinal and pelvic motions may contribute to, or result from, common running injuries.
    No preview · Article · Feb 2016 · Human movement science
  • Source
    • "Tibialis activity starts at take-off and ends at touchdown, with peak activation before touchdown (Gazendam and Hof, 2007;). On level ground, the movement is periodic and the activity patterns are fairly repetitive (Gazendam and Hof, 2007; Guidetti et al., 1996; Ishikawa et al., 2007;). In case of a variation of the movement, e.g. "
    [Show abstract] [Hide abstract] ABSTRACT: While running on uneven ground, humans are able to negotiate visible but also camouflaged changes in ground level. Previous studies have shown that the leg kinematics before touch down change with ground level. The present study experimentally investigated the contributions of visual perception (visual feedback), proprioceptive feedback and feed-forward patterns to the muscle activity responsible for these adaptations. The activity of three bilateral lower limb muscles (m. gastrocnemius medialis, m. tibialis anterior and m. vastus medialis) of nine healthy subjects was recorded during running across visible (drop of 0, −5 and −10 cm) and camouflaged changes in ground level (drop of 0 and −10 cm). The results reveal that at touchdown with longer flight time, m. tibialis anterior activation decreases and m. vastus medialis activation increases purely by feed-forward driven (flight time-dependent) muscle activation patterns, while m. gastrocnemius medialis activation increase is additionally influenced by visual feedback. Thus, feed-forward driven muscle activation patterns are sufficient to explain the experimentally observed adjustments of the leg at touchdown.
    Full-text · Article · Feb 2015 · Journal of Experimental Biology
  • Source
    • "Muscle activities during running have been examined to study the effects of speed (e.g. Gazendam and Hof, 2007) and gait modifications (e.g. Giandolini et al., 2013) on muscle activity. "
    [Show abstract] [Hide abstract] ABSTRACT: Running research has focused on reducing injuries by changing running technique. One proposed method is to change from rearfoot striking (RFS) to forefoot striking (FFS) because FFS is thought to be a more natural running pattern that may reduce loading and injury risk. Muscle activity affects loading and influences running patterns; however, the differences in muscle activity between natural FFS runners and natural RFS runners are unknown. The purpose of this study was to measure muscle activity in natural FFS runners and natural RFS runners. We tested the hypotheses that tibialis anterior activity would be significantly lower while activity of the plantarflexors would be significantly greater in FFS runners, compared to RFS runners, during late swing phase and early stance phase. Gait kinematics, ground reaction forces and electromyographic patterns of ten muscles were collected from twelve natural RFS runners and ten natural FFS runners. The root mean square (RMS) of each muscle's activity was calculated during terminal swing phase and early stance phase. We found significantly lower RMS activity in the tibialis anterior in FFS runners during terminal swing phase, compared to RFS runners. In contrast, the medial and lateral gastrocnemius showed significantly greater RMS activity in terminal swing phase in FFS runners. No significant differences were found during early stance phase for the tibialis anterior or the plantarflexors. Recognizing the differences in muscle activity between FFS and RFS runners is an important step toward understanding how foot strike patterns may contribute to different types of injury.
    Full-text · Article · Nov 2014 · Journal of Biomechanics
Show more