I played racquetball with my right arm....last time I played was in the early 1990's. To this day my right arm muscle is larger than my left. I played every day & in competitions with high level players not just once in awhile.

Sometimes some things we do create that.

On another extreme, I blew our my ACL playing racquetball & needed knee reconstruction before it was done arthroscopically. My leg was in a cast for a month after the surgery. When the cast came off my leg had atrophied to skin & bone. Lots of PT for 6 months & I was downhill skiing with a brace but it took years of focused work for that leg to regain the muscle mass it lost. Can't tell the difference now (except for the huge scar).

Dedicated focus on the smaller muscle to develop it is the only way to counter that