Effects of short-term, low-intensity resistance training with vascular restriction on arterial compliance in untrained young men

Previous studies have shown that low-intensity resistance training with restricted blood flow, known as KAATSU training, increases muscle strength and size. Its effects on blood vessel function, however, have not been examined. We compared the effects of a short-term KAATSU resistance training protocol and traditional high-intensity resistance training on muscle strength and blood vessel function in young, untrained men. Male volunteers were randomly assigned to a KAATSU resistance training group (KR, n=10), a traditional resistance training group (RT, n=10), or a KAATSU-only group (K, n=10). Both KR and RT groups trained 3 times per week for 3 weeks doing leg press (LP), knee flexion (KF), and knee extension (KE) isotonic resistance exercises. Training sessions consisted of 5-10 min of warm-up, followed by 2 sets of 10 repetitions at 80% of 1 repetition maximum (1-RM) for the RT group, while the KR group performed the resistance exercises with vascular restriction at a load of 20% of 1-RM. The K group had only the vascular restriction treatment for 3 weeks. Muscle strength (1-RM) and arterial compliance (pulse contour analysis) were assessed at baseline and after training. Both the KR and RT groups did not show changes in arterial compliance of the large or small arteries (P>0.05) after training. There were significant time effects (P<0.05 pre- vs. posttraining); however, resistance training generally resulted in greater relative improvements in strength. Arterial compliance of the large and small arteries was not affected by the either the KAATSU or traditional high-intensity resistance training interventions.