Hmm...Interesting...thanks Jamie....But I have read that Heavy wieghts build more bulk than functional strength??? Due to muscle memory also when doing heavy wieghts you need to go slow and use form to properly isolate the correct muscles, but while doing a lighter higher rep weight session you can use more explosive movement while still keeping proper form....I believe the recovery is where they differ...ie...when doing heavy weights the rec now a days is do one body part per week....7 day recovery between body parts...but yet you are still working out 4 - 5 times a week... while doing my circuit I have only 24 hours of rest between workouts...not good from what i have read....