Fig. 3.
Correlations of the percentage changes in ratios of glycolytic (PFK) to fatty acid oxidative (COX) enzyme activities with skeletal muscle work efficiency (solid circles) and the RER (solid squares) during low-level exercise (bicycling to generate 10 W of power) in subjects studied before (Wtinitial) and after (Wt−10%) weight loss. Regression equations are percentage change in efficiency = −1.38 (PFK/COX) + 1.54, R2 = 0.56, P < 0.0001 and percentage change in RER = 0.48 (PFK/COX) − 3.81, R2 = 0.29; P = 0.008