Apparently the makers of akavar 20/50 are facing a lawsuit right now based on unsupported claims. akavar 20/50 is a rebranded version of Estrin-D which was a pill marketed to menopausal women. Looking at the ingredients, its just a caffeine pill and has multiple sources of caffeine including green tea, guarana, yerba mate, etc. It'd be safer and cheaper just to drink coffee or tea.
You can't out-exercise poor eating habits.