Taking 8 grams of L-citrulline or 12 grams of L-citrulline DL-malate daily for six weeks may help resistance-trained men perform more repetitions to failure in bench press and incline press exercises compared to taking a placebo.

In men who regularly lift weights, taking L-citrulline and citrulline malate leads to similar improvements in upper body endurance and nitric oxide metabolite levels after exercise, meaning adding malate does not provide extra performance benefits.

In men who regularly lift weights, taking L-citrulline or citrulline malate supplements for six weeks does not lead to greater increases in maximum strength compared to not taking them, even though everyone in the study got stronger.

Taking L-citrulline or citrulline malate regularly may raise levels of nitric oxide metabolites after exercise in men who train with weights, and both forms appear to have comparable effects.

Taking a supplement called L-citrulline every day for a week, plus a little more right before riding a bike for 4 km, makes healthy, fit men feel less tired and more focused right after they finish the ride.

Taking L-citrulline or citrulline malate supplements does not lower the levels of lactate or urea in the blood after resistance exercise in men who regularly train with weights.