Hello Doctor, I Feel Pain On Side Exterior Of Right

Hello Doctor,

I feel pain on side exterior of right knee joint when I run on hard surfaces. I had an MRI done on the knee and found Myxoid degeneration and ganglion cyst formation on ACL.
Since I dont feel any pain during other activities such as walking or in the gym, extend of degeneration might be minor.
But I have been advised by the dotor not to run and play contact sports which really sucks. So I wanted to know whether this can be treated and improve the condition of the knee.

Thanks,
Mithil