Elevation could be the answer.
It is difficult to breathe in Colorado . The elevation seems to have that effect. One website described it as the air pressure outside being lower than the air pressure in a person’s lungs, which makes it difficult to breathe (among other things). I’ve experienced it. Running through the mountains - with no one else around - I felt shortness of breath, and after trying to push through it (like I’ve been known to do), I relented and walked for a bit. Hiking in the mountains had a similar effect. While running (and hiking) with my five year old, I experienced a different feeling. My attention was given to his breathing and his success, and I didn’t notice that I had a problem breathing. Sure, I was moving at a slower pace, but there is something to the idea of helping someone else succeed rather than being self-focused. In social-psychology it is called moral elevation (or sometimes just elevation). It’s been studied in detail within the past thirty ye...