Modified Kaatsu training: adaptations and subject perceptions.

PURPOSE: Although Kaatsu training involves low training loads, high perceived exertion and pain scores suggest that potential benefits may be offset by poor adherence or tolerance, particularly if applied in untrained or clinical populations. The purpose of this study was to investigate muscle adaptations, perceived exertion ratings, perceived sensations, and exercise adherence to a modified Kaatsu training protocol involving upper arm exercise.

METHODS: Forty subjects ages 18-30 yr were assigned to exercise (EX) or nonexercise control (CON) groups. The EX group performed three sets of 15 repetitions of unilateral biceps and triceps exercises, three times per week for 8 wk while wearing a pneumatic cuff to restrict blood flow on one arm (CUFF) and nothing on the other (NCUFF). The CON group did not exercise but wore the cuff on one arm for a comparable amount of time. Strength, girth, tomography scans along with RPE, and sensations during workouts were assessed. Perceived exertion and sensations were assessed during workouts using visual analog scales.

RESULTS: Biceps curl and triceps extension strength along with arm size increased during the 8-wk period when compared with the CON group. Compliance was 85.4% and 97% for the EX and CON groups, respectively. EX subjects completed 85.4% of their workouts, whereas controls attended 90.4% of their sessions. The prominent sensations reported in the CUFF arm were pressure and aching.

CONCLUSIONS: The Kaatsu training used in this study yielded moderate exertion ratings and low-pressure sensations, increased muscle size and strength, and was well tolerated, thereby lending support to Kaatsu training's potential as a training modality for untrained or clinical populations.