MB and heart failure: 2004). For rats in heart failure, deranged vascular control accelerated the fall in PmvO2 following the onset of contractions and slowed its recovery upon cessation of contractions (Copp et al. 2010). However, inconsistent with our hypothesis, following heavy intensity exercise the deoxy[Hb + Mb] off‐transient MRT in the RF‐d muscle was greater (i.e. slower recovery) than that of the VL‐s (Fig. 1 and Table 2); with both muscles returning to, or below, the pre‐exercise baselines within the 6 min observation period.