After 1-2 KAATSU Cycles (Cycle 20 is a great warmup for non-athletes or Cycle 60 for high-level athletes) and perhaps after completing the standard KAATSU 3-point exercises (i.e., hand clenches + biceps curls + triceps extensions), try to do the KAATSU Push-up Challenge (i.e., three sets of push-ups with your Optimal SKU levels in the KAATSU Air Bands).
Do the first set of push-ups until you reach muscular or technical failure. Ideally, your Optimal SKU will allow you to do between 25-40 push-ups.
Then rest 20 seconds and start your second set of push-ups. Do the second set of push-ups until you reach muscular or technical failure.
Ideally, if your Optimal SKU is set properly, you will not be able to repeat the same number of push-ups in the second set as you did in the first set. You may be able to do only 10-20 push-ups on the second set. This is OK and actually exactly what you want.
Then rest 20 seconds and start your third set of push-ups. Do the third set of push-ups until you reach muscular or technical failure.
Ideally, your number of push-ups will decrease again. This indicates you have set your Optimal SKU.
This is a great way to build strength and develop tone in your upper body.