I am 21 years old. I am a young man with a nice body figure. I started smoking about 3 years ago. At first, I could not match with it and I stopped. But the second time I found it easy. Now I smoke regularly. I am continuing it more than 1 year. Firstly my muscles decreased. With time I regained my fitness. But the problem is that I feel tired all time. I can not get up early and miss my classes often. Even I feel oscitation in classroom. What can I do now? Is there any recovery except avoiding smoking.