Hm, lean AND muscular? I'd say do both cardio and a bit of weights. I rarely run but that's because I want to be more muscular. If you want to have an even-scaled body type, don't overdo one for the other -- meaning don't run more and lift less. Try to even it out.
OH!, buy protein and mix it with 1% or skim milk. That will help you gain some weight which will then become muscle, but it's not too much that it'll become fat.
Alright, thanks so much man. And is which kind of protein? I heard one should buy whey protein when working out.
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