I answered "Yes" with the understanding derived from being an old time cross country runner (back when the distances were measured in miles, not kilometers, thus a 5 mile race was a 5 mile race.) During the early parts of training and getting in shape my legs would ache ceaselessly, and my lungs felt as if they would burst. But as I got into shape, those things which "challenged" me early no longer did.
Should we endanger a student? No.
Should we push them past self-created limits? Yes.
The great runner Wilma Rudolph suffered from polio. She was challenged to exceed her limits and became a champion.