Sprinting can be a useful cardio exercise that involves the heart & lower extremities.
I'm not sure how it would replace actual strength training that focuses on challenging & strengthening the glutes, hamstrings, calves, quads, etc??
I liked the info. presented in P.A.C.E. regarding long "haul" cardio or short term (all done in 30 min or less.) alsearsmd.com/pace2/jvnb/
This is NOT meant to be an advertisement, but info. that I've used to replace what I do.