I am a 22 y/o male weight lifter.I have several hard knots under my skin close to the abdominal wall. The largest one 3 inches superior and 1/2 inch to lateral right. It is slightly tender to touch. I performed the hernia test. it was negative. it doesn't hurt to contract the abdominals. I sometimes get these on other parts of the body too. What can it be? I would be thankfull for any help.

Optional Information:
Male , Age: 22