I've tried a handful of bike rides while fasting. I usually ride in the morning, 20-40 miles. Typically I would have yogurt with granola in it as breakfast, then go ride. So fasting usually had no food, except yesterday I had some coffee with creamer to have *something* in there.
Doesn't feel good. I feel mostly "empty" and tired, almost like I bonked, and it's hard to really get in there and push feel like I'm kicking ass.
Confounding factors:
- Very windy outside which is extremely demoralizing. Like I'll usually average about 19mph on a ride, and sometimes the wind is so bad I'm going like 12mph and it feels like shit and makes the ride miserable.
- Been having bad nights at work, so I approach the ride already tired from only getting 2-3 hours of sleep, and being on my legs all day the day before
Basically when fasting I start the ride off the same way I feel when I'm usually halfway through a longer ride and feel energy depleted. On those rides I usually carry a energy gel thing to consume, and I'll carry a gatorade in my 2nd water bottle holder that has calories in it too.