At 19yo, following a year off training after HS, then summer & fall easy running, my coach had me work with the sprinters for about 6 weeks to introduce a decent speed reserve.
(Btw it worked, as I was then able to cruise thru 300m repeats @ 40 and 400m repeats @ 54, on an undersized unbanked indoor track while wearing thick, heavy stability trainers plus orthotics -- as a guy returning to running with a HS PR of 50.7. I could never have run those workouts 1.5 years earlier in HS.)
Our sprinters' warmup: 400m slow jog, stretch, 400m jog, 3 x 75m accelerations with increasing intensity. Then into the workout. Never any injuries in the group.
Looking back, I'd suggest adding a few 40m mobility drills before the accelerations.