Exercise and postprandial lipid metabolism.

Energy expenditure and fat oxidation are both profoundly increased in exercise. In absolute terms, fat oxidation is greatest during exercise of moderate intensity (60-65 % maximum 0 2 uptake, vo2,,) when subjects following a mixed diet may oxidize between 0.3 and 0.7g fat/min, rFpresenting up to 60% of energy expended (Saltin & Astrand, 1993). Because the capacity of muscle fibres to synthesize fatty acids de novo is limited (Saggerson er al. 1992), the bulk of fatty acids has to be supplied from extracellular sources. It is likely, therefore, that postprandial lipid acquisition by muscle will be modified during and/or after exercise.