Fig. 7. Mean absolute error in estimates of the thermal equivalent of either CO₂ production or O₂ consumption produced by assuming that protein is conserved and using the respiratory exchange ratio to estimate the fractional content of lipids and carbohydrates in the catabolic substrate. Filled circles indicate N=10. Unfilled circles indicate that sample size was reduced below 10 because RER values outside of the range of 0.71-1.00 did not allow estimation of thermal equivalents for some individuals.