sorry to hear that. I had a double hernia once but fortunatly they both healed themselves but it took some time as i recall.
What you do not want to do is tear your repair by overstressing the muscles and ligaments locally but you do need to keep your muscles toned and limit athrophy

This is where the NHS lets us down badly I feel.
You should have been referred to a Physiotherapist either by your Dr or the Hospital.
Your Physio should have considerable first hand experience of others with your problem and be able to assess you and create an individual program for you to bring you back to full strength and mobility.
My advice would be to go to your Dr explain that you are a keen sportsman/athelete and need a referral to a physio for a program of recovery training. Dr's are lazy B's Grrrr