Betaine increases cellular water retention through osmosis. The ability of betaine to maintain hydration reduces the negative impact that dehydration can have on exercise performance - and help your muscles look fuller with more volume after your training session on top of fuel post-workout muscle gains!
Betaineās uncanny ability to function as an osmolyte increases muscle growth by causing the muscle fiber to swell.
Research has shown that muscle cell swelling stimulates protein synthesis and decreases protein breakdown, resulting in muscle growth.
Some of betaineās muscle-building effects likely come from its capacity to donate a methyl group, which simply consists of one carbon atom and three hydrogen atoms, which has been shown to increase the production of creatine.
Betaineās ability to function as a methyl donor increases the uptake of creatine into the muscle cell by stimulating the conversion of homocysteine into methionine, which effectively lowers homocysteine levels.
Since higher homocysteine levels have been shown to impair insulin signaling lower homocysteine levels caused by betaine should improve insulin sensitivity, and therefore the insulin-driven uptake of creatine into the muscle cell.
The ability of betaine to increase creatine production and muscle cell uptake is likely the primary reason why betaine has been shown to significantly increase anaerobic power (strength gains!) in key lifts like the bench press and squat