Does education work in a similar fashion? does being very good at solving very specific timed algorithm problems at a whiteboard translate to being a good software engineer overall? If that's all you trained for, you will be just very good at that.
As to pushups and pulling things, back strength from supporting your body weight on your shoulders would help you pull things. Clearly practicing the motion you want to improve is optimal, but controlled motion generally involves a lot more skeletal muscles than just what’s being targeted.
I have a clear difference in my body structure after i ever did and made it to 15 push ups.
And now after 8 month of not doing it at all, it still lingers around.
This adds to my confidence.
Same with my java skills.
To use your analogy; it gets tricky doing push-ups because my body remembers doing crunches and my knees get in the way.
Better analogy: I'm learning German at the moment, but my brain keeps "helpfully" supplying the French word whenever I'm mentally grepping for German vocab.
Remembering that JS switches need a break statement but Go switches don't - or that JS If statements need the brackets but not the braces, and Go If statements don't need the brackets but do need the braces. This shit trips me up even after years of coding in just JS and Go.
Disclaimer: I used to write code without internet access every day for years (was in a secured area where internet and phones are not allowed).
I learned to write java code (structure, basic io (terminal, file, datastructures) blind like in word or notepad and it would run without errors for a google interview; It is not that much you need to know actually but when you learn it once, it lingers around for quite a long time and it gives you a different feeling of confidence that you actually know java (i was writing java code for 6? years before that already so i do know java).
Its very similiar to my personal experience with doing push ups: If you never have done them you don't have any muscles at certain areas; Now after going from 0 to 15 push ups over a few month, i gained a general better physiology on upper body strenge and it still lingers around.
Non of both are critical in a day to day scenario but both experiences were fun/interesting and this base is now here where it was not before.
It brings me, mentally speaking, closer to really get something like java.