sprint days & full recovery in between sprints

what does full recovery exactly mean?

Enough time allowing for the replenishment of ATP as well as enough time allow for your central nervous system to recover.
The rule of themb we like to use is rest 1 minute for every 10 meters traveled. So for a 60 meter sprint rest 6 minutes. For reps over 200 such as a 300 a 15-20 min. rest is usually sufficent.