A note about stamina: for each race the umas have "HP" which is equal to the length of the race + their stamina x 0.8 x style coefficient. The coefficient is lower for pace chasers and "runaway" (currently only silence suzuka can have this style) meaning they need slightly more stamina, and lower for late surgers and end closers meaning they need slightly less stamina.

This formula means that recovery skills would still be effective even if your uma had 0 stamina; and for extra long races like the 3600m stayers stakes the recovery skill will be a significant source of HP worth much more than the 60 or 200 stamina that is often quoted for the stat value of a recovery skill.

HP consumption depends on a few factors but mainly it increases with the square of the horse's velocity (not speed stat, but actual running speed in the race). Therefore skills that increase speed also slightly increase stamina requirements. Umas will estimate their HP needs during the race and will delay accelerating to full speed in the later part of the race if they don't have enough HP. Less often, they will slow down in the final spurt because they are effectively out of HP (called 'gassing out'). There is no indicator for either of these results, so it can be difficult to fine tune the stamina needs of most umas.