This idea for [tag]softball tryout drills[/tag] was sent to me by Dan. It is   a great conditioning drill for all softball players.Softball Tryout Drills

From Dan… I end 95% of practices with this drill:
 
Players form 2 equal lines, facing first base –
Line ‘A’ beginning in the right batters box, and Line ‘B’ about 15′ up and to the right of the first base line.  
On my ‘Go’ command, the first runner in each line runs, ‘A’ to first, and ‘B’ through first and on to second.   Once the first two runners are on base, my commands become, “Primary”, “Secondary”, and then either “Go” or “Back”.   On “Go”, the runner on second scores, the runner on first ends up at third, B ends up on second and A on first.   As a runner scores, they go to the rear of the opposite line from where they started that lap.  

I run this [tag]softball[/tag] [tag]drill[/tag] for about 15 minutes or more, until I’m satisfied that they’re giving maximum effort.   It’s a great [tag]conditioning drill[/tag].   Players caught dogging it are given extra laps around the complex.   Things to focus on in doing the drill:   proper rounding of bases, especially first to second; proper primary and secondary leads, and no crossing over steps; reaction time returning to base or breaking for the next; speed and endurance.