The rapid hyperaemia at the onset of exercise is considered to partly rely on the mechano-sensitivity of the vascular network (Clifford & Tschakovsky, 2008). This is conveniently investigated by means of short lasting muscle compressions (MC), which mimic the hyperaemic response of brief muscle contractions. How the hyperaemia develops upon repetitive mechanical stimulation is currently unknown, both potentiated and attenuated responses having been observed following repetition of the stimulus (Clifford et al., 2006; Kirby et al 2007). The issue is however of interest, given that motor activity is frequently characterized by repetitive muscle contractions. The present study aims at investigating the hyperaemic response to repetitive MC. The study complies with the national guidelines for animal care and has been approved by the local ethical committee. Muscle blood flow is continuously measured from the masseteric artery of anesthetized rabbits. Data are collected bilaterally from 5 rabbits (n=10 arteries) anesthetized with urethane (1.2 g/kg, i.v.). Mechanical compression of the masseter muscle is exerted by a cylindrical head (diameter=2cm) moved by a PC-driven servo-controlled motor motor (local pressure = about 120 mmHg). Repetitive MC (1 s ON, 1 s OFF, for 25 s) transiently increased blood flow (measured during OFF periods) up to 580 ± 145 % (mean + STD), time to peak= 4.1 ± 1.4 s. Blood flow then decreased towards baseline in spite of continuing stimulation (half return time= 8 ± 5.5 s). Repetitive 1-s MC at constant rate (stimulation period: 2 s to 4 min) produced instead stable hyperaemic responses whose peak amplitude decreased with decreasing stimulation period (1-way ANOVA, p<0.01): from 457 ± 208 % (4 min) to 163 ± 60 % (20 s) to 25 ± 15 % (2 s). The observation that the amplitude of the hyperaemic response decreases by more than 50% when the stimulation period decreases from 4 min in to 20 s suggests that the mechano-sensitivity of the vascular network undergoes some transient “inactivation” after stimulation. The results highlight the transient nature of the hyperaemia produced by repetitive muscle compression and may explains the contradictory data in the literature as well as the similar hyperaemic pattern observed in response to the mechanical stimulation produced by repetitive passive limb movement (Trinity et al 2011). In addition, this characteristics fits well with the hypothesis that the mechano-sensitivity of the vascular network mediates a feed-forward control of muscle blood flow at the beginning of exercise, leaving to other mechanisms the responsibility to match blood flow to the actual metabolic demand during prolonged muscle activity.