i dont know if cycling will stimulate natural
test levels. only blood work will tell you if your levels are in the normal range. eating ots of food has alot to do with gaining weight/mass...as you've found out.
as for your low
test levels when you were younger, maybe whatever it was that was causing it just fixed itself...went away. just taking a shot in the dark on that one. but go get your levels tested again and see where you're at.
have a nice day