What is occlusion training?
First developed in Japan, occlusion training is a form of physical training that involves restriction of blood flow within the body. More precisely, occlusion training prevents venous blood flow OUT of the body part being trained, whilst arterial blood can still be pumped IN. 1
How does it work?
Restricting venous return from the working muscle group with a band prevents the release of lactic acid and other waste products. This causes increased muscular stress triggering hormonal responses that promote muscular growth.1
Show me the science! (because I can't stand BS)
Evidence #1: Growth hormone (and IGF-1), norepinephrine, and lactate demonstrated increases after 5 sets of 14 repetitions each at 20% of 1 repetition maximum (1RM) for bilateral leg extensions compared to the control group.2
Evidence #2: In another study, NCAA Division 1A football players had increases in bench press and squat 1RM as well as upper and lower chest girths after 3 weeks of occlusion training compared to the control group.3
Evidence #3: Cook et al. also found rugby athletes had improvements in bench press, squat, maximum sprint time, and leg power with observations of greater exercise-induced salivary testosterone and cortisol responses.4 Additionally, this study suggested that occlusion training may be systemic as bench press strength improved with lower-body occlusion.4