I think the user interface for data entry is the key problem in using software to track gym workouts. I lift 4x per week and have tried various workout logging

I think the user interface for data entry is the key problem in using software to track gym workouts. I lift 4x per week and have tried various workout logging software, but have yet to find anything that works better than a simple notebook and pen. A typical session's data includes 6 exercises, 4 sets each, weight and rep count for each set, so 48 numbers altogether, all related to each other in different ways. Plus I like to keep notes in the margin like "grip the bar wider" or "slower negative movement". If you can create an iphone app with a user interface that makes it really really easy to enter workout data, then I think you would find a large market. I payed for gyminee.com because I thought it might deliver this, but the data entry was still too annoying. The built-in Notes program on the iphone was actually better. Also, as other people have mentioned, "overtraining" has negative connotations, so I'm curious why you picked this name. Best of luck. I think this is something people want.