Yay, a running thread.
I have recently started running again. I am using a heart rate monitor to keep my heart rate at 180 - age, which is very slow at my age. This is supposed to help me build a good aerobic base, which I totally lack. It's helped me stick to the running that's for sure. I always burn out after a couple weeks. I've been running now for a month.
I eat fairly low carb. The only carbs I usually get are from things like tomatoes or beets or now and then some yams or fresh figs. Rarely I'll have a little rice, but this is not even weekly.
I think my body resists the fat-burning state with all its might. This weekend I went for a run fasted, without breakfast. My stomach was growling. About half hour to 45 minutes in, the growling stopped and I suddenly felt energetic and good. I was able to continue for another 2 hours and never felt tired or anything.
This seems to happen often. The first half hour is really hard and then something switches over and I have plenty of energy and feel happy. I wonder if that's when my body finally switches over to using fat for energy.
Female, 5'3", 50, Max squat: 202.5lbs. Max deadlift: 225 x 3.