So basically I have a 6 day workout program. 3 days I lift weights and the other 3 days i do some sort of cardio. 2 of the 3 cardio days I do distance running (>6 miles). On the other day I can't decide between doing sprints (100m and 200m) or swimming laps. My overall goals are to tone up, get a 6-pack, and build muscle. Which workout would be better in terms of my goals? Maybe I should do swimming one week and sprints the next? Any advice is appreciated, thanks!