How can I benefit greater from cycling?

I cycle fairly regularly, 2 or 3 times a week, as well as my main sport of football. however i try to cycle in order to build up the strength in my thighs as i suffer from the adolescent injury of osgood-schlatters disease and so dont want to do much more running than i need to. Therefore how would you say is the best way i can benefit from cycling. For example should i be more aggressive when going up hills etc. I cycle the same route pretty much, reasonably hilly usually with a fairly large hill on the way and a reasonable slope for about 400m on the other route. i generally do these in gear 5 and then the top 1 to 4 gears in the more precise gears. many thanks!!