Getting my cardio upto decent levels (using the Couch 2 4k program) has done wonders for all my other physical pursuits. I can do callisthenics till the muscles

Getting my cardio upto decent levels (using the Couch 2 4k program) has done wonders for all my other physical pursuits. I can do callisthenics till the muscles become sore rather than just cardio fatigue. The same during martial arts practice and everything else. It's very high ROI.