Distress, stage 1, eustress, primary stress is a positive physiological response to stress

"Eustress" is a positive psychological response to a stressor as indicated by the presence of positive psychological states such as enthusiasm, motivation, excitement, activeness, alertness.

-Medical Student (College Level)

the more fit you are, the faster the recovery. your heart rate drops most sharply in the first minute after you stop exercising; it should then fall about 20 beats a minute—a drop of less than 12 beats a minute is considered abnormal. this “recovery heart rate” is measured as part of an exercise stress test.