| Title |
Muscle architecture and EMG activity changes during isotonic and isokinetic eccentric exercises
|
|---|---|
| Published in |
European Journal of Applied Physiology, March 2011
|
| DOI | 10.1007/s00421-011-1894-3 |
| Pubmed ID | |
| Authors |
Gaël Guilhem, Christophe Cornu, Arnaud Guével |
| Abstract |
The present study aimed to compare muscle architecture and electromyographic activity during isotonic (IT) and isokinetic (IK) knee extensors eccentric contractions. Seventeen subjects were assigned in test and reproducibility groups. During test session, subjects performed two IT and two IK sets of eccentric contractions of knee extensor muscles. Torque, angular velocity, VL architecture and EMG activity of agonist (vastus lateralis, VL; vastus medialis; rectus femoris) and antagonist (semitendinosus; biceps femoris, BF) muscles were simultaneously recorded and averaged on a 5° window. Torque-angle and angular velocity-angle relationships exhibited differences in mechanical load between the IT and IK modes. Changes in muscle architecture were similar in both modes, since VL fascicles length increased and fascicle angle decreased, resulting in a decrease in muscle thickness during eccentric contraction. Agonist activity and BF co-activity levels were higher in IT mode than in IK mode at short muscle lengths, whereas agonist activity was higher in IK mode than in IT mode at long muscle lengths. Differences in mechanical load between both modes induced specific neuromuscular responses in terms of agonist activity and antagonist co-activity. These results suggest that specific neural adaptations may occur after IT or IK eccentric training. This hypothesis needs to be tested in order to gain new insights concerning the most effective eccentric protocols based on whether the objective is sportive or clinical. |
Mendeley readers
The data shown below were compiled from readership statistics for 159 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Norway | 2 | 1% |
| France | 1 | <1% |
| Belgium | 1 | <1% |
| Spain | 1 | <1% |
| United States | 1 | <1% |
| Unknown | 153 | 96% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Master | 23 | 14% |
| Student > Ph. D. Student | 22 | 14% |
| Student > Bachelor | 18 | 11% |
| Student > Postgraduate | 14 | 9% |
| Researcher | 12 | 8% |
| Other | 31 | 19% |
| Unknown | 39 | 25% |
| Readers by discipline | Count | As % |
|---|---|---|
| Sports and Recreations | 56 | 35% |
| Medicine and Dentistry | 21 | 13% |
| Nursing and Health Professions | 10 | 6% |
| Engineering | 9 | 6% |
| Biochemistry, Genetics and Molecular Biology | 3 | 2% |
| Other | 9 | 6% |
| Unknown | 51 | 32% |
Attention Score in Context
This research output has an Altmetric Attention Score of 1. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 01 February 2015.
All research outputs
#22,760,732
of 25,374,917 outputs
Outputs from European Journal of Applied Physiology
#4,069
of 4,345 outputs
Outputs of similar age
#112,257
of 119,059 outputs
Outputs of similar age from European Journal of Applied Physiology
#45
of 51 outputs
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