I'm 5'8 130lbs and 18. I don't have much body fat and I'm lean. I'm a distance runner and I'm looking to make gains in my performance and was looking into anabolics (anavarol, clenbutrol, etc.) I've heard people don't suggest it due to weight gains that have negative effects but due to my size and narrow build, I'm not too concerned about that. What I am concerned about is joint damage due to side effects. Advice? I need better stamina, speed, cardiovascular endurance, and just more red blood cells/ oxygen to the muscles. I've heard about hgh as well.