Generic but vital: the update fixes a crash that could occur when transitioning from Adventure mode to Mini-games after 90+ minutes of continuous play.
If you want, I can instead:
Ring Fit Adventure Switch NSP: The Ultimate Fitness Update Guide
The Ring-Con relies entirely on the precision of the Joy-Con sensors to detect your squeezes and stretches. Updates often include optimizations for the Joy-Con connectivity to reduce input lag or "false positives" (where the game thinks you squeezed the ring when you didn't). This makes the gameplay feel tighter and more responsive.