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Differences in post-exercise T2 relaxation time changes between eccentric and concentric contractions of the elbow
Eisuke Ochi1, Yosuke Tsuchiya2, Kazunori Nosaka3
1Faculty of Bioscience and Applied Chemistry, Hosei University, 3-7-2, Kajino, Koganei, Tokyo, 184-8584, Japan. ochi@hosei.ac.jp.
European Journal of Applied Physiology
|September 16, 2016
Summary
Eccentric contractions caused greater muscle damage than concentric contractions, indicated by reduced torque and soreness. However, T2 changes after eccentric exercise did not correlate with other muscle damage markers.
Area of Science:
- Exercise physiology
- Muscle damage research
- Magnetic resonance imaging applications
Background:
- Eccentric (ECC) and concentric (CON) contractions elicit different responses in muscle.
- Understanding muscle damage markers is crucial for exercise science and rehabilitation.
Purpose of the Study:
- To compare maximal ECC and CON elbow flexor contractions.
- To assess changes in transverse relaxation time (T2) and indirect muscle damage markers.
Main Methods:
- Twelve young men performed maximal isokinetic ECC and CON exercises.
- Magnetic resonance imaging assessed T2 and cross-sectional area (CSA).
- Maximal voluntary isometric contraction (MVC) torque, range of motion (ROM), and soreness were measured.
Main Results:
- ECC resulted in greater MVC torque loss and ROM decrease than CON.
- Muscle soreness was only observed after ECC.
- T2 increased more after CON immediately post-exercise, but showed delayed increases after ECC.
Conclusions:
- Muscle activity during ECC may be lower than CON, despite greater damage.
- T2 changes after ECC are not consistently related to other indirect muscle damage markers.
Keywords:
Cross-sectional areaDelayed onset muscle sorenessMagnetic resonance imagingMuscle damageMuscle functionTransverse relaxation timeMore Related Videos
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