I only tend to run 3 times a week and do other sports on the other days - just make sure you get 3 hard runs in each week, perhaps some speed/hill work, a tempo run and a long run, and fit in your other sessions around that.
Cycling and swimming would equate to an easy run, though football does take it out of you a lot. I do speed/hills on a tues, 50mins football on a weds, and 8mile tempo on Thurs - by friday I'm pooped!
As Grant says, I reckon you're best bet would be to find a 3 runs-a week schedule and cross train on your rest days.
