Figure 6. Effect of exercise duration on skeletal muscle Ca²⁺–calmodulin-dependent protein kinase II expression and phosphorylation.

Skeletal muscle extract proteins were immunoblotted for Ca²⁺–calmodulin-dependent protein kinase II expression (CaMKII; top panel) and phospho-Thr²⁸⁷ CaMKII (middle panel). The bottom panel is signal intensity for phospho-Thr²⁸⁷ CaMKII relative to CaMKII expression. Representative immunoblots are shown and CaMKII isoforms are indicated. Data are mean ± s.e.m., n = 8. †P < 0.01 versus time 0, 10, 30, 60 and 90 min; *P < 0.05 versus time 0.