Q: mike, I recently experienced, that when I was doing a high intensity cardiovascular excercise on the cross trainer, I surpassed what I beleive to be my pain barrier, and I felt almost euphoric for several minutes. Where I usually fatigue and come to an end at 30 mins, I kept going strong approaching 40, and considerably increased my distance and calculated calorie burn. The only reason I stopped was because I was worried about overdoing things. Is this normal at all? Is it safe to keep going? Adam UK

A: Sounds like you experienced what is called 'runner's high'! Congratulations! The exact experience of runner's high is individual but feeling of euphoria like you described is quite common. It's certainly nothing to worry about and you should be happy and proud you got to experience it!