If you don't need the whole rest then your not pushing hard enough on the sprint. But try 60-30 (shouldn't have enough time to totally recover). a
And the 60 should be pretty much max effort. Youll know you're doing it right if you have trouble finishing the set at the end. Repeats are close to max heart rate, little bit of rest. And if your legs are really feeling good, on Friday start at a moderate pace (break in) , then pick it up for your second half. Teaches your legs to push even when they "feel" tired. Big time runner, mostly distance but I know the speed training. Hopefully helping...