Before September 2003, I was not the most conditioned fighter in the world.  My cardiovascular fitness had a thirty-thirty second time span before I was gassed.  However, after spending one month focusing on 1000 repetition drills in my training, my conditioning has never been the same.
Basically, all I did was perform 1000 repetitions in one workout.  This exercise accompanied other elements of my workout, but it provides many significant benefits that have made me who I am today.   The workout I will be presenting is a variation of that moment in time, and it can provide a little creativity to your current training.

1000 Pyramid

In this workout, we will only be focusing on boxing technique.  Perform these exercises on a heavy bag or a body shield if you are training with a partner.
Jab – Perform 50 jabs as fast as you can.  After 50 reps are complete, switch sides.
Cross – Perform 50 cross or back punches fast as you can, then switch sides.
Hook – Perform 50 hooks as fast as you can, then switch sides.
Uppercuts – Perform 50 uppercut punches as fast as you can, then switch sides.
Back Fist – Perform 50 back fists as fast as you can, then switch sides.
You should have just completed 500 repetitions, and you focused on speed.  Now it is time to go down the pyramid.
Back Fist – Perform 50 repetitions as hard as you can, then switch sides.
Uppercuts – Perform 50 repetitions as hard as you can, then switch sides.
Hooks – Perform 50 repetitions as hard as you can, then switch sides.
Cross – Perform 50 repetitions as hard as you can, then switch sides.
Jab – Perform 50 repetitions as hard as you can, then switch sides.
You finally finished the other 500 repetitions, but now you focused on strong, powerful strikes.
Benefits
The 1000 Pyramid workout has more benefits than just improving cardiovascular fitness.  It will also improve your technique if executed correctly, speed, and power.
Conclusion
This workout can also be modified with other exercises.  Mix it up with boxing combinations, kicking techniques, or kickboxing combinations.