I've done it twice. My bi's range from 16.1 to 16.5" cold in the morning, depending on how much I've been working out. Given: I'm able to inject 2 cc in either shoulder without a nudge of soreness the next day. What I tried: 1/2 cc of medical grade (I'm on TRT) cypionate into right bicep. Inner head. Maybe 5/8" into the muscle. What happened: Hard to straighten arm totally. Arm too sore to work out for about 3 days. What I tried: 1/2 cc of medical grade (I'm on TRT) cypionate into left bicep. Inner head. Maybe 5/8" into the muscle. What happened: Arm was shot for about 6 days. Lost alot of training time. Bicep became red, looking like a bad sunburn. i'm guessing a reaction, oil probably leaked out of muscle to under skin. Given the travel of the redness, it would be consistent with that. Hard to straighten arm. Bicep swollen. Great stretch of fascia, if that is what you are going for. Possible conclusions: - I'm an idiot. lol... had to beat someone to that one. - Bicep injections are not worth it. May lead to lots of problems, loss of training time.