[scewLacysmazy]

Aerobic exercise does not increase muscle mass. It does cause increases in vascularity (blood vessels) to allow the muscle to replenish its energy stores more efficiently. It can add a little mass when a beginner starts an exercise program. Aerobics increase "aerobic capacity", so the more you do the exercise, the longer and harder you can do the exercise, and hence the more energy you can burn during a single session.

Lifting does build mass, but I agree that the amount a person can gain is limited by genetics and the ability to continue to fatigue the muscle in less than 12 reps. Once you reach a certain level, and the weight gets quite heavy, it gets harder to increase. For example, I am pushing 200 lbs on bench. Even though my chest can handle it, my hands and wrists have also got to deal with the weight. I also realize that I need a spotter nearby because if I go to failure I won't be able to muscle it back up so easily. My goal is to get to 225 - that's enough for me. If you look at body builders from 40 years ago and compare them to today's elite, you see the impact that steroids and other chemicals have made to strength training. I don't like the look of the huge muscles. I much prefer the physique of the prior generation.

I also agree that my belief that my muscle would equate to a 1 hour bike ride each day do not seem to have materialized. Since I don't measure and record everything I eat, however, it is hard to tell. I know that it helps.