Ali twists his ankle quite badly in the last ten minutes of his school’s championship soccer game. he continues to play and does not notice the pain in his ankle. this is probably because of an increase in his levels.

Endorphin.

Explanation:

As per the description given, Ali's present situation would be due to increased 'endorphin levels' that make him feel lesser pain. 'Endorphin' is demonstrated as the chemicals that the human nervous system secretes to cope up with the stress or pain that humans suffer. Due to the wound that Ali receives during the Soccer game, his nervous produces a sufficient amount of 'endorphin' and due to which he feels 'lesser pain' and 'continues to play' without giving attention to his pain.

did you ever get an answer? i'm on the same question : (