Post by John A. Casler on Jan 2, 2009 14:39:41 GMT -8
The below may be of interest:
========================
Jamie Carruthers posted the following to SuperTraining
========================
bjsm.bmj.com/cgi/content/abstract/42/12/989
Response of growth and myogenic factors in human skeletal muscle to
strength training
Y Liu1, M Heinichen1, K Wirth2, D Schmidtbleicher2, J M Steinacker1
British Journal of Sports Medicine 2008;42:989-993
Objective: To investigate the response to different strength training
techniques of growth and myogenic factors in human skeletal muscle,
with particular emphasis on satellite cell (SC) activation.
Methods: 24 volunteers were divided into two groups and performed a 6-
week strength training (group A trained with maximum contraction and
group B had training combined with maximum contractions, ballistic
movement and stretching-shortening cycles). Muscle biopsies were
obtained from triceps brachii 3 days before and 7 days after
training. For estimating gene expression of insulin-like growth
factor (IGF-1), mechano growth factor (MGF), MyoD and myogenin, real-
time RT-PCR was performed.
Results: In group A, there was an increase in the 1 repeat maximum
(1RM), but no change in Vmax (maximum movement velocity) and an
increase in MHC (myosin heavy chain) IIa and a decrease in MHC IIx;
in group B both 1RM and Vmax increased significantly along with an
increase in MHC IIa and a decrease in MHC I. The MGF gene expression
increased significantly in both groups (by 1160% and 59%,
respectively), and IGF-1 increased only in group A (by 335%). MyoD
and myogenin gene expression increased in group A (by 107% and 94%,
respectively) but did not change in group B.
Conclusions: Response of growth and myogenic factors occurs during
muscular adaptation to a prolonged training, and strength training
with different strategies caused different responses with respect to
gene expression of these factors. These results suggest that SC
activation is involved in the muscular adaptation process to training
and might be attributed to MHC isoform transition.
========================
Jamie Carruthers posted the following to SuperTraining
========================
bjsm.bmj.com/cgi/content/abstract/42/12/989
Response of growth and myogenic factors in human skeletal muscle to
strength training
Y Liu1, M Heinichen1, K Wirth2, D Schmidtbleicher2, J M Steinacker1
British Journal of Sports Medicine 2008;42:989-993
Objective: To investigate the response to different strength training
techniques of growth and myogenic factors in human skeletal muscle,
with particular emphasis on satellite cell (SC) activation.
Methods: 24 volunteers were divided into two groups and performed a 6-
week strength training (group A trained with maximum contraction and
group B had training combined with maximum contractions, ballistic
movement and stretching-shortening cycles). Muscle biopsies were
obtained from triceps brachii 3 days before and 7 days after
training. For estimating gene expression of insulin-like growth
factor (IGF-1), mechano growth factor (MGF), MyoD and myogenin, real-
time RT-PCR was performed.
Results: In group A, there was an increase in the 1 repeat maximum
(1RM), but no change in Vmax (maximum movement velocity) and an
increase in MHC (myosin heavy chain) IIa and a decrease in MHC IIx;
in group B both 1RM and Vmax increased significantly along with an
increase in MHC IIa and a decrease in MHC I. The MGF gene expression
increased significantly in both groups (by 1160% and 59%,
respectively), and IGF-1 increased only in group A (by 335%). MyoD
and myogenin gene expression increased in group A (by 107% and 94%,
respectively) but did not change in group B.
Conclusions: Response of growth and myogenic factors occurs during
muscular adaptation to a prolonged training, and strength training
with different strategies caused different responses with respect to
gene expression of these factors. These results suggest that SC
activation is involved in the muscular adaptation process to training
and might be attributed to MHC isoform transition.