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Facilitation of quadriceps activation following a concentrically controlled knee flexion movement: the influence of transition rate.
J Orthop Sports Phys Ther. 2001 Mar; 31(3):122-9; discussion 130-2.JO

Abstract

STUDY DESIGN

Single group repeated measures design.

OBJECTIVE

To determine if the rate of transition between knee flexion and extension influences the subsequent concentric activation of the quadriceps and knee extension torque during reciprocal movements.

BACKGROUND

Preloading a muscle by stretching, a prior isometric or eccentric muscle action, or a prior movement controlled concentrically by the antagonist muscle group increases the maximal torque-generating capability of the agonist. We hypothesized that the rate of transition from the prior movement may be the critical factor that influences the degree of muscle facilitation and torque potentiation. Rapid reversal of antagonistic movements has been postulated as a potential facilitatory mechanism.

METHODS

Knee extension torque and electromyographic (EMG) amplitude (dependent variables) from 2 of the vasti muscles were recorded while subjects (N = 20; 12 men, 8 women, mean age, 28.5+/-2.68 years) maximally activated their quadriceps at 3 constant angular velocities, 100 degrees/s, 200 degrees/s, and 300 degrees/s, and 2 preload conditions, SLOW and RAPID (independent variables). In the SLOW transition condition, subjects actively flexed their knee to 110 degrees from an extended position, paused in this position for 3 seconds, and then extended to 0 degrees. In the RAPID transition condition, the same movement from knee flexion to extension was performed without a pause.

RESULTS

Peak torque, the root-mean-square (RMS) average, peak (peak rectified and smoothed), and initial (100 milliseconds prior to torque onset) EMG amplitudes were all significantly greater during the RAPID transition condition. Peak torque decreased with increasing movement velocity. There were no interactions between the preload conditions and angular velocity on peak torque or the EMG amplitude variables. There was also no influence of velocity on the EMG amplitude variables.

CONCLUSIONS

The effect of preloading the quadriceps by prior concentric activation of the hamstrings is dependent on the rate of transition between the flexion and extension movements and is due primarily to neural facilitation.

Authors+Show Affiliations

Department of Physical Therapy, University of Florida, Gainesville 32610-0154, USA.No affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article

Language

eng

PubMed ID

11297017

Citation

Jeon, H S., et al. "Facilitation of Quadriceps Activation Following a Concentrically Controlled Knee Flexion Movement: the Influence of Transition Rate." The Journal of Orthopaedic and Sports Physical Therapy, vol. 31, no. 3, 2001, pp. 122-9; discussion 130-2.
Jeon HS, Trimble MH, Brunt D, et al. Facilitation of quadriceps activation following a concentrically controlled knee flexion movement: the influence of transition rate. J Orthop Sports Phys Ther. 2001;31(3):122-9; discussion 130-2.
Jeon, H. S., Trimble, M. H., Brunt, D., & Robinson, M. E. (2001). Facilitation of quadriceps activation following a concentrically controlled knee flexion movement: the influence of transition rate. The Journal of Orthopaedic and Sports Physical Therapy, 31(3), 122-9; discussion 130-2.
Jeon HS, et al. Facilitation of Quadriceps Activation Following a Concentrically Controlled Knee Flexion Movement: the Influence of Transition Rate. J Orthop Sports Phys Ther. 2001;31(3):122-9; discussion 130-2. PubMed PMID: 11297017.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Facilitation of quadriceps activation following a concentrically controlled knee flexion movement: the influence of transition rate. AU - Jeon,H S, AU - Trimble,M H, AU - Brunt,D, AU - Robinson,M E, PY - 2001/4/12/pubmed PY - 2001/7/6/medline PY - 2001/4/12/entrez SP - 122-9; discussion 130-2 JF - The Journal of orthopaedic and sports physical therapy JO - J Orthop Sports Phys Ther VL - 31 IS - 3 N2 - STUDY DESIGN: Single group repeated measures design. OBJECTIVE: To determine if the rate of transition between knee flexion and extension influences the subsequent concentric activation of the quadriceps and knee extension torque during reciprocal movements. BACKGROUND: Preloading a muscle by stretching, a prior isometric or eccentric muscle action, or a prior movement controlled concentrically by the antagonist muscle group increases the maximal torque-generating capability of the agonist. We hypothesized that the rate of transition from the prior movement may be the critical factor that influences the degree of muscle facilitation and torque potentiation. Rapid reversal of antagonistic movements has been postulated as a potential facilitatory mechanism. METHODS: Knee extension torque and electromyographic (EMG) amplitude (dependent variables) from 2 of the vasti muscles were recorded while subjects (N = 20; 12 men, 8 women, mean age, 28.5+/-2.68 years) maximally activated their quadriceps at 3 constant angular velocities, 100 degrees/s, 200 degrees/s, and 300 degrees/s, and 2 preload conditions, SLOW and RAPID (independent variables). In the SLOW transition condition, subjects actively flexed their knee to 110 degrees from an extended position, paused in this position for 3 seconds, and then extended to 0 degrees. In the RAPID transition condition, the same movement from knee flexion to extension was performed without a pause. RESULTS: Peak torque, the root-mean-square (RMS) average, peak (peak rectified and smoothed), and initial (100 milliseconds prior to torque onset) EMG amplitudes were all significantly greater during the RAPID transition condition. Peak torque decreased with increasing movement velocity. There were no interactions between the preload conditions and angular velocity on peak torque or the EMG amplitude variables. There was also no influence of velocity on the EMG amplitude variables. CONCLUSIONS: The effect of preloading the quadriceps by prior concentric activation of the hamstrings is dependent on the rate of transition between the flexion and extension movements and is due primarily to neural facilitation. SN - 0190-6011 UR - https://www.unboundmedicine.com/medline/citation/11297017/Facilitation_of_quadriceps_activation_following_a_concentrically_controlled_knee_flexion_movement:_the_influence_of_transition_rate_ L2 - https://www.jospt.org/doi/10.2519/jospt.2001.31.3.122?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub=pubmed DB - PRIME DP - Unbound Medicine ER -