z_bumbi
2010-10-03, 07:59
Med Sci Sports Exerc. 2010 Aug 2. [Epub ahead of print]
Effects of Flexibility Training On Eccentric Exercise-Induced Muscle Damage.
Chen CH, Nosaka K, Chen HL, Lin MJ, Tseng KW, Chen TC.
1Department of Physical Education, National Chiayi University, Chiayi County, TAIWAN; 2School and Graduate Institute of Physical Therapy, National Taiwan University, Taipei City, TAIWAN; 3School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Western Australia, AUSTRALIA; 4Graduate Institute of Sport Coaching Science, Chinese Culture University, Taipei City, TAIWAN; 5Department of Physical Education and Health, Taipei Physical Education College, Taipei City, TAIWAN.
Abstract
PURPOSE: This study investigated whether flexibility training would attenuate muscle damage induced by maximal eccentric exercise.
METHODS: Thirty untrained young men were allocated to static stretching (SS), proprioceptive neuromuscular facilitation (PNF), or control group (n=10 per group). The SS consisted of 30 sets of a 30-s standard static stretching with a 30-s rest between sets, and the PNF included 5 sets of the 30-s standard static stretching followed by 3 sets of 3 "contract-relax-agonist-contract" procedures. These were performed 3 times a week for 8 weeks, and all subjects performed 6 sets of 10 maximal isokinetic (30 degrees .s) lengthening contractions of the knee flexors after the 8-week training or 8-week after the baseline measures (control). Changes in indirect markers of muscle damage before and for 5 days after the eccentric exercise were compared amongst the groups.
RESULTS: The range of motion (ROM) of the hip joint increased by 25 degrees , and the optimum angle of the knee flexors shifted (P<0.05) to a longer muscle length by 10 degrees after training, without significant differences between SS and PNF. No significant changes in these variables were evident for the control group. Compared with the control group, the SS and PNF groups showed smaller decreases and faster recovery of knee flexor muscle strength, and smaller (P<0.05) changes in optimum angle, ROM, muscle soreness, and plasma creatine kinase activity and myoglobin concentration without significant differences between the groups. The pre-eccentric exercise ROM or optimum angle was correlated (P<0.05) with the changes in the muscle damage markers.
CONCLUSION: These results suggest that both SS and PNF training are effective in attenuating eccentric exercise-induced muscle damage, and flexible muscles are less susceptible to the damage.
Effects of Flexibility Training On Eccentric Exercise-Induced Muscle Damage.
Chen CH, Nosaka K, Chen HL, Lin MJ, Tseng KW, Chen TC.
1Department of Physical Education, National Chiayi University, Chiayi County, TAIWAN; 2School and Graduate Institute of Physical Therapy, National Taiwan University, Taipei City, TAIWAN; 3School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Western Australia, AUSTRALIA; 4Graduate Institute of Sport Coaching Science, Chinese Culture University, Taipei City, TAIWAN; 5Department of Physical Education and Health, Taipei Physical Education College, Taipei City, TAIWAN.
Abstract
PURPOSE: This study investigated whether flexibility training would attenuate muscle damage induced by maximal eccentric exercise.
METHODS: Thirty untrained young men were allocated to static stretching (SS), proprioceptive neuromuscular facilitation (PNF), or control group (n=10 per group). The SS consisted of 30 sets of a 30-s standard static stretching with a 30-s rest between sets, and the PNF included 5 sets of the 30-s standard static stretching followed by 3 sets of 3 "contract-relax-agonist-contract" procedures. These were performed 3 times a week for 8 weeks, and all subjects performed 6 sets of 10 maximal isokinetic (30 degrees .s) lengthening contractions of the knee flexors after the 8-week training or 8-week after the baseline measures (control). Changes in indirect markers of muscle damage before and for 5 days after the eccentric exercise were compared amongst the groups.
RESULTS: The range of motion (ROM) of the hip joint increased by 25 degrees , and the optimum angle of the knee flexors shifted (P<0.05) to a longer muscle length by 10 degrees after training, without significant differences between SS and PNF. No significant changes in these variables were evident for the control group. Compared with the control group, the SS and PNF groups showed smaller decreases and faster recovery of knee flexor muscle strength, and smaller (P<0.05) changes in optimum angle, ROM, muscle soreness, and plasma creatine kinase activity and myoglobin concentration without significant differences between the groups. The pre-eccentric exercise ROM or optimum angle was correlated (P<0.05) with the changes in the muscle damage markers.
CONCLUSION: These results suggest that both SS and PNF training are effective in attenuating eccentric exercise-induced muscle damage, and flexible muscles are less susceptible to the damage.