I've been strength training with FB for almost two years now, and as happy as I am with the results, I'm still not where I want to be in terms of toning and muscle definition, in fact my arms are bordering on bulky, which is not what I want.

I mostly follow along with K&D but I heard that I was supposed to lift lighter and do up to 20 reps, or drop the weights completely and do more bodyweight only workouts. I guess what I'm asking is, is that true? do I have to choose between building strength by lifting heavier and heavier, or getting a better muscle definition? I'm talking both upper and lower body here. Thanks for the answers