Yup, getting back into pushup shape is harder than I'd expected. Last week I did a few sets of 5 each. This week I could do 10 the first set, then 7, then 5, then nothing... no burning or cramping muscles, just like paralysis... couldn't do another no matter how hard I tried. Flopped on the floor and had roll over to get up.

On the plus side I can do pushups again. After my shoulder break and dislocation last May it took months just to get most range of motion back, let alone any real strength.

I'm still not convinced any test involving arm or upper body strength is as useful a cardio fitness indicator as leg strength for most folks. Even among dedicated athletes, including dancers and skaters, there are far more sports requiring leg strength and relatively little arm use.