I've been using RPM/Drive for six weeks now. I've had remarkable results from using them, and couldn't be happier.
Two weeks ago I noticed that approximately 60-70 minutes after taking the pre-workout dose, I got really sluggish and tired in the gym. It didn't happen every day, but two or three times a week, this happened to me.
I haven't switched anything up since the beginning - I take three Drive at 7am, and three Drive at 3pm, an hour before going to the gym. I also take four RPM at 3pm as well.
My sleeping patterns and diet have remained consistent throughout this, so I was unsure if it was the Drive or the RPM, although at a glance it would be hard to see RPM as the culprit.
On days that I skip the afternoon dose of Drive, I power through the workouts. When I use it, the sluggish feeling returns.
Is there any logical explanation for this?