I was talking to an instructor/trainer at the gym after taking her class. It's ball class so concentrates more on core than strength training. But, I always go heavier anyway (as class weights go, like 18 lb body bar), even though I rarely get to fatigue. She said she thought it was too heavy and there's no need to go higher than a 12 pound body bar. That would be a non-workout for me. Would there be any point in lifting if it's easy the whole time? This trainer is knowledgeable as rehab and injuries go but I'm not convinced she's as knowledgeable as weight training goes. But, I can't think of a reason to lift w/ light weights if you're not ever feeling it.