Related Experiment Video
Updated: Apr 15, 2026

Measurement of Insulin- and Contraction-Stimulated Glucose Uptake in Isolated and Incubated Mature Skeletal Muscle from Mice
Published on: May 16, 2021
Exercise type and volume alter signaling pathways regulating skeletal muscle glucose uptake and protein synthesis
Juha P Ahtiainen1, Simon Walker, Mika Silvennoinen
1Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland, juha.ahtiainen@jyu.fi.
Purpose:
The aim of this study was to compare activation of cellular signaling pathways regulating protein synthesis and glucose uptake in skeletal muscle between resistance and endurance exercise. Moreover, the effect of resistance exercise volume was examined.
Methods:
Three groups of male volunteers (26 ± 3 years) were examined: 5 × 10 repetition maximum (RM) resistance exercise (RE) with leg press device (5 × 10 RE; n = 8), 10 × 10 RE (n = 11), and endurance exercise (strenuous 50-min walking with extra load on a treadmill; EE; n = 8). Muscle biopsies were obtained from m.vastus lateralis 30 min pre- and post-exercise.
Results:
Downstream markers of mTORC1, p-p70S6K(Thr421/Ser424) and p-rpS6(Ser240/244), increased more after 10 × 10 RE than after 5 × 10 RE (p < 0.05) and EE (p < 0.01-0.001). Exercise-induced changes in p-IRS-I(Ser636/639) that inhibit IRS-I signaling via negative feedback from hyperactivated mTORC1 signaling were greater (p < 0.05) after 10 × 10 RE compared with 5 × 10 RE and EE. The changes in energy sensor p-AMPKα(Thr172) were greater after 10 × 10 RE and EE (p < 0.05-0.01) than after 5 × 10 RE. A major regulator of glucose uptake in muscle, p-AS160(Thr642), increased more after 10 × 10 RE than after 5 × 10 RE (p < 0.01) and EE (p < 0.05).
Conclusion:
10 × 10 RE induced greater activation of important signaling proteins regulating glucose uptake (p-AS160) and protein synthesis (p-p70S6K, p-rpS6) than 5 × 10 RE and EE. The present findings further suggest that, especially after 10 × 10 RE, IRS-I signaling is downregulated and that AS160 is activated through AMPK signaling pathway.
Related Concept Videos
Exercise and Muscle Performance
Endurance exercises
Endurance exercises involve running, swimming, or cycling, which require repetitive movements with low force output. When a person engages in endurance exercise, a few noticeable changes occur in their skeletal muscles. For instance, the number of capillaries...
Insulin: The Receptor and Signaling Pathways
cAMP-dependent Protein Kinase Pathways
Hormones Regulating Blood Glucose
In addition to accelerating glucose uptake and utilization, insulin has...
PI3K/mTOR/AKT Signaling Pathway
Cells Coordinate Growth and Proliferation

