Hi. So After Masturbation, My Muscles That I Use Often

Hi. So after masturbation, my muscles that I use often such as my legs, feet, thighs, become sore. The soreness gets better after time. However, after it comes back again after masturbating. Im worried it might be a sign of cancer or any health-related or genital-related problem. Do you have any answers that might explain why this happens?