I'm a guy and I turned 18 years old last May and I currently weigh 115 pounds and I have a height of 5'7 or 5'8 I think.. I tried GNC's Weight Gainer 1850 last summer, It did some help to me but I stopped it cause it's quite expensive. Anyways, I am aware that my metabolism's high too. I'm not into this 'Go to the gym' idea because I do not have time but I do push ups regularly at my home. Please? Anyone who have read this thread, please add some comments and give me ideas and things/stuff I should do.
And a postscript question, by any possibility, will my metabolism start to slow down significantly in my current age (18)? Thank you!