In summary, NIRS measurements of mitochondrial function can be made with both VOL and ES exercises. The intensity of both ES and VOL exercises does not influence the measurement of the recovery of mVO2. The recovery of mVO2 after low- to moderate-intensity exercise appears to follow a monoexponential function, and measurements can be made with reasonably small increases in mVO2. NIRS represents an important new methodology for assessing muscle energetics, and future studies should aim to apply NIRS measurements to various populations of interest. © 2013 the American Physiological Society.