Lifting weights, top heavy?

I recently had a foot injury which willprevent me from doing leg workouts for a month or two (squats, deadlifts, etc..). 2-a-days are in a month and a half and i do not want to lose strength. Would it be wise to just lift upper body and get stronger? My Max for bench press is 220 and squat is like 275. My upperbody is very close to the same strength of my legs which i know is bad. But now with this injury, my legs will only get weaker. Should i continue upper body lifts. If so, will my speed suffer?