Schematic representation of reactive hyperaemia and measurements realised from laser Doppler recording. 1: Mean blood flow at rest (Φrest). 2: Peak flow (Φpeak). 3: Time to peak. 4: ΔΦ = Φpeak - Φrest. 5: Time to flow normalisation. 6: Time to half flow normalisation. 7: First upward slope calculated for the first 3 seconds. 8: Second upward slope calculated for the second half.