I used to be like you babyboomergirl, not having breakfast much at all in my 20's and early 30's.

And my breakfasts right now, remain modestly small as I outlined earlier on type of food in this thread. So imagine, I used to eat even less.

It changed when I returned to cycling in my early 30's because I needed something in my stomach to do a bike ride early morning to get to work.. which was 13-16 kms. one way for 14 yrs., depending where I was working. usually the bike ride then and now, where we live in a different city, includes at least 1 hill 6-10% grade to chug up or more hills, depending what I feel like doing/how time I have.

It was also highly critical for long vacation bike rides when we travelled by bike for 5-6 hrs., each day that I eat a substantive breakfast. I have been in 2 different situations where I didn't eat much breakfast and I nearly fainted after cycling for 30-40 kms. in hot humid summer morning at 28-30 degrees C. Experiences like that are scary.

So I have this feeling if you engaged in high cardiovascular exercise early morning for at least 1 hr., that the body would require a breakfast earlier. With running and cycling if one doesn't eat,..a person is geographically stranded outdoors.

If I don't bike, but just walk to catch subway/bus, then a cup of tea, maybe with a fruit would suffice for breakfast.

I know my stomach becomes acclimatized to certain eating patterns and timing. It didn't used to be like that. But then, when I was much younger I didn't have to worry about weight, fitness since I had a high metabolic rate. I am petite and at an excellent fit weight (at age 51) but it does take more conscious regular effort on my part now.