Steve McDermott
New Member
Hi Guys, here are a couple of interesting studies on the effects of creatine and resistance training. It seems that creatine can increase GLUT4 in muscle and thus increase insulin sensitivity.
J Appl Physiol 2003 Jan 10; [epub ahead of print] Related Articles, Links
Combined creatine and protein supplementation in conjunction with resistance training promotes muscle GLUT4 content and glucose tolerance in humans.
Derave W, Eijnde BO, Verbessem P, Ramaekers M, Van Leemputte M, Richter EA, Hespel P.
Department of Kinesiology, Exercise Physiology and Biomechanics, K.U.Leuven, Leuven, Belgium.
The present study was undertaken to explore the effects of creatine and creatine plus protein supplementation on GLUT4 and glycogen content of human skeletal muscle. This was investigated in muscles undergoing a decrease (immobilization) and subsequent increase (resistance training) in activity level, as compared with muscles with unaltered activity pattern. A double-blind placebo-controlled trial was performed on 33 young healthy subjects. The subjects' right legs were immobilized with a cast for 2 weeks, followed by a 6-week resistance training program for the right knee-extensor muscles. The participants were supplemented throughout the study with either placebo (P) or creatine ©, or with creatine during immobilization and creatine plus protein during retraining (CP). Needle biopsies were bilaterally taken from the vastus lateralis. GLUT4 protein expression was reduced by the immobilization in either group (p<0.05). During retraining GLUT4 content increased (p<0.05) in both C (+24%) and CP (+33%), which resulted in higher post-training GLUT4 expression compared to P (p<0.05). Compared with P, muscle glycogen content was higher (P < 0.05) in the trained leg in both C and CP. Supplements had no effect on GLUT4 expression or glycogen content in contralateral control legs. Area under the glucose curve during the oral glucose tolerance test was decreased from 232 +/- 23 at baseline to 170 +/- 23 mmol.l(-1).min at the end of the retraining period in CP (p<0.05), but did not change in C or P. We conclude that creatine intake stimulates GLUT4 and glycogen content in human muscle only when combined with changes in habitual activity level. Furthermore, combined protein and creatine supplementation improved oral glucose tolerance, which is supposedly unrelated to the changes in muscle GLUT4 expression.
And another one.....
Another study (Diabetes)
Steve
J Appl Physiol 2003 Jan 10; [epub ahead of print] Related Articles, Links
Combined creatine and protein supplementation in conjunction with resistance training promotes muscle GLUT4 content and glucose tolerance in humans.
Derave W, Eijnde BO, Verbessem P, Ramaekers M, Van Leemputte M, Richter EA, Hespel P.
Department of Kinesiology, Exercise Physiology and Biomechanics, K.U.Leuven, Leuven, Belgium.
The present study was undertaken to explore the effects of creatine and creatine plus protein supplementation on GLUT4 and glycogen content of human skeletal muscle. This was investigated in muscles undergoing a decrease (immobilization) and subsequent increase (resistance training) in activity level, as compared with muscles with unaltered activity pattern. A double-blind placebo-controlled trial was performed on 33 young healthy subjects. The subjects' right legs were immobilized with a cast for 2 weeks, followed by a 6-week resistance training program for the right knee-extensor muscles. The participants were supplemented throughout the study with either placebo (P) or creatine ©, or with creatine during immobilization and creatine plus protein during retraining (CP). Needle biopsies were bilaterally taken from the vastus lateralis. GLUT4 protein expression was reduced by the immobilization in either group (p<0.05). During retraining GLUT4 content increased (p<0.05) in both C (+24%) and CP (+33%), which resulted in higher post-training GLUT4 expression compared to P (p<0.05). Compared with P, muscle glycogen content was higher (P < 0.05) in the trained leg in both C and CP. Supplements had no effect on GLUT4 expression or glycogen content in contralateral control legs. Area under the glucose curve during the oral glucose tolerance test was decreased from 232 +/- 23 at baseline to 170 +/- 23 mmol.l(-1).min at the end of the retraining period in CP (p<0.05), but did not change in C or P. We conclude that creatine intake stimulates GLUT4 and glycogen content in human muscle only when combined with changes in habitual activity level. Furthermore, combined protein and creatine supplementation improved oral glucose tolerance, which is supposedly unrelated to the changes in muscle GLUT4 expression.
And another one.....
Another study (Diabetes)
Steve