The net abounds with the proposition that for weight loss you need to to keep your metabolism ramped up after a workout so that you will 'burn off' those nasty little fat calories faster. You accomplish this , supposedly, by doing such things as HIIT. However it is muscle mass that burns those extra calories...not just the fact that you are 'amped'..(also known as 'idling'...in another thread). So.....you need to increase musclemass. Accomplished through a weight resistance program of a kind. But......intense long lifting sessions and HIIT both produce Cortisol....which if left unchecked is counterproductive to muscle growth and noticably moreso the older you get. The more lean musclemass you have the more you will burn calories at rest regardless of whether you are "amped" or not. If you don't have much muscle mass but you have lots of bodyfat....you are "amped" for nothing except to prolong the stress-related co-efficients which are doing you no good as far as optimal muscle building results go.Depending on how you lift/exercise, the more 'amped' you will be after working out and by-and -large the "amp" will be counterproductive from a stressor point-of-view. In my opinion, immediately post workout, one needs to do something like meditation in order to lower the post workout stress response as quickly as possible. I also think that going to bed "jacked and ramped" is counterproductive. Just before bed I do stretching and some Yoga as well as meditation. I want my metabolism as slow as possible when I sleep. I will sleep deeper, better, and wake up refreshed. If I am "amped" during my sleep, the stressors are still in effect which are counterproductive to muscle growth. 'Amped' is good when you are lifting......but IMO you need to turn it off or lessen it right away after that for optimal results. Less stress equals a better CNS..and the better shape your CNS is in the better your glandular/hormone responses for growth will be. Just my two cents worth........ (And on the flip side of the coin....if you are one of these people that is a high-strung, fidgety, can't-sit-still-for-a minute,"hardgainer" with a normal metabolic rate equal to a sparrow.....you do not want to be "amped" at all. You want the exact opposite for best results regarding the acquisition of musclemass.).