Effects Of Short Term Low Intensity Resistance Training With Kaatsu On Bone Metabolic Markers In Untrained Young Men

Abstract

Recently, low-intensity resistance training with KAATSU has been shown to increase muscle strength and size. Its effects on bone metabolic markers, however, have not been established. PURPOSE: To compare the effects of short-term KAATSU resistance training and traditional high-intensity resistance training on muscle strength and bone metabolic markers in young men (mean ± SD, 23.54 ± 0.72 yrs). METHODS: Male volunteers were randomly assigned to either a KAATSU resistance training group (KR, n = 10), a traditional resistance training group (RT, n = 10), or KAATSU only group (K, n = 10). Both KR and RT groups performed 3 weeks of resistance training for leg press (LP), knee extension (KE), and knee flexion (KF) isotonic exercises. Sessions consisted of 5-10 minutes of warm-up, followed by 2 sets of 10 reps at either 20% 1RM for the KR or 80% 1RM for the RT for 3 times a week. For the KT and K groups, a pressure cuff was place on the proximal end of both thighs and inflated to a pressure determined by each subject's systolic pressure. The K group underwent KAATSU procedure without the exercise protocol for 10 minutes during the training. Body composition (DXA), muscle strength (1RM), and bone formation (bone-specific alkaline phosphatase, BAP) and bone resorption (cross-linked C-telopeptide of Type-1 collagen, CTX) markers were assessed at baseline and after training. RESULTS: At baseline, there were no group differences in body composition, or strength variables (P > 0.05). All groups significantly (P < 0.05) improved LP, KF, and KE strength after training. A significant group time interaction was observed for KE (P < 0.01) with RT exhibiting greater increases than KR and K (29.19% vs. 13.41% vs. 8.76%, respectively). RT showed a significant increase (P < 0.01) in BAP compared to KR and K (50.91 % vs. 6.73% vs. -6.1%). There were no significant (P > 0.05) effects for serum CTX concentrations after 3 weeks of training. CONCLUSIONS: Traditional high-intensity resistance training was more effective than low-intensity with KAATSU training for increasing bone formation and for improving knee extension strength.