Originally Posted by drizzt3117
It depends, but not to the same degree as a diet etc. A solid weightlifting regimen over a period of time, say 3-6 months, will build a solid core of lean muscle mass. Even if you stop lifting as consistently or at all, and simply supplement this with body weight exercises, or not, your metabolism will stay above baseline for much longer then if you lost the weight through cardio/diet. Eventually you'll lose muscle mass if you don't use it, but you can go a number of years without lifting and get back to a high level of lifting potential in a very short time (I did this after going abroad for several years) because of muscle memory.
I agree with what you are saying about the benefits of weight lifting, but still think that it is not really necessary unless you enjoy it as a hobby.
The reason is because I am not talking about DIET in a sense of limiting calories or going without eating, etc. I am just talking about eating normally, which is in a healthy manner. If you do that and incorporate it into your lifestyle, it does not matter what kind of genetics, etc.
IF weight lifting is required to keep the stomach flat or body lean, then that means you have to continue doing it your whole life. This does not sound normal or natural to me.
Also, I do not think that a 19 year old needs a BOOST in metabolism by lifting weights or whatever method anyway. A 19 year old should have a high enough metabolism to remain in good shape if he lives a normal, healthy lifestyle.
When he becomes 39 or something and starts having trouble maintaining his body like a 19 year old, then maybe he will need to put in extra effort with more physical activity like weights or strenuous sports.