Lactate after exercise in man: III. Properties of the compartment model

Lactate movements during recovery following muscular exercise in man were studied by means of a two-compartment model. Mathematical discussion of the literal expressions obtained allows one to represent parameters concerning lactate exchange, utilization, and production in the previously working muscles and in the remaining lactate distribution space. It also shows that bi-exponential time courses predicted for muscular and blood lactate concentrations as well as for rates of lactate uptake, release, and utilization can denote several morphologies. All of the time evolutions for muscular and blood lactate concentrations found in the literature are consistent with these theoretical possibilities in the model. A numerical application confirms this concordance. Thus, this simple model, for which the basic assumption were previously justified, appears to be qualitatively able to describe lactate exchanges and disappearance after exercise. A practical algorithm is put forward to display its possibilities and to test further its quantitative validity.