Near-infrared spectroscopy (NIRS)-obtained brain (frontal cortex) oxygenation data during KE before and after BR. Mean (SD) values of changes in concentration of oxyhemoglobin (Δ[oxyHb]; A), changes in concentration of deoxyhemoglobin (Δ[deoxyHb]; B), and changes in concentration of total (oxy + deoxy) hemoglobin (Δ[oxyHb+deoxyHb]; C), all expressed as micromolar changes relative to an initial value arbitrarily set equal to zero, are shown as a function of work rate. *P < 0.05, before vs. after BR at the same relative work rate. See text for further details.