I'm not into all the Jack3D and NoXplode. I've tried those before and that tickly loopy feeling is unbareable. B-12 gives me the focus I want on compound lift days. Plus its half life is in hours. I inject IM during my warm ups and it gives me all the focus I need. I've been using b-12 for a few years. By the time your workout is complete you are pissing about 50% of it away.