Good comments in here.
When it comes to 60 times making sure your start is sound is key, spend most your time on this and flexibility...(yoga isnt just a fad, its valuable to serious athletes) will pay dividends ...i also suggest spending a ton of time on 10 and 20 yard sprints during practice, rather than a ton of 60s...
Lastly core work and even shoulder strength play in...everything working in unison without weak or soft points in your physique matters. Good luck! Shaving a 1/10 a YEAR can take a 7.00 freshman to 6.6, which puts him in a good place.