We are a commune of inquiring, skeptical, politically centrist, capitalist, anglophile, traditionalist New England Yankee humans, humanoids, and animals with many interests beyond and above politics. Each of us has had a high-school education (or GED), but all had ADD so didn't pay attention very well, especially the dogs. Each one of us does "try my best to be just like I am," and none of us enjoys working for others, including for Maggie, from whom we receive neither a nickel nor a dime. Freedom from nags, cranks, government, do-gooders, control-freaks and idiots is all that we ask for.
Box jumps (and jumping squats) are types of Calisthenics which are technically plyometric.That is to say, explosive movement. Good stuff. Ball slams are the other explosive calisthenic exercise that I do routinely. All good additions to your grueling calisthenic circuits. 20" jumps are difficult after a while.
With calis, it's all about the circuits or what I call the circus in which you are the performing animal.
Don't forget to breathe during tough calisthenics - and everything else! We find the best way to remember to breathe during exercise is to make sure to exhale and the inhale will take care of itself. Coaches and trainers should say "Exhale," not "breathe." Oxygen is very good stuff for aerobic organisms.