Fitness and Nutrition Tracking Internet Software

I need a software piece to be created and implemented into a website I have. Unfortunately the website is not build yet but will be within the next week to week and a half. I am using Membergate ([login to view URL]) for my membership software. It would be great if you have familiarity with this software. The application will be used by end users to input and track their fitness results. The application should then be able to display these results in a well-organized fashion allowing the visitors to visually see the progress they are making in regards to the weight they use, the reps they complete, etc. There will be 10-15 total variables needed to be tracked and displayed as well as an area for users to input comments.