Could the pulmonary V˙O2 off-transient response to maximal short-term exercise be better characterized by a triexponential decay?

The off-transient pulmonary oxygen uptake (V˙O2) response to a single bout of intense, exhaustive exercise has been characterized over the years by a second-order exponential model. In this paper, we report the superiority of a third-order exponential decay in describing the V˙O2 off-kinetics after a maximal cycling exercise lasting 60-s. Our findings are in accordance with a biphasic pattern of phosphocreatine resynthesis when muscle pH is affected.