I kinda do that with the pre work out. That has more caffeine and b vitamins than your average energy drink and from what I understand that's what gives you the energy boost well ginsing and taurine also. But I used to drink alot if those I think it was the desk job after sitting and making calls fir a couple hours I needed a jolt!!!

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Do not dwell in the past, do not dream of the future, concentrate the mind on the present moment. --buddah