Fasting and exercise


I’m working on stopping overeating, have adopted a no-flour no-sugar protocol and am currently trying intermittent fasting. I’ve been using an 11 – 7 or 12 – 8 eating window.
I love to hike, and it’s a big part of my compelling reason for doing this. I don’t currently have the strength or stamina to do some of the hikes I’d like to be doing, but I have a number of shorter, less-challenging hikes that I like to do that challenge me physically but I can do. I want to achieve a health and fitness level where I can try backpacking!
So, hiking isn’t new exercise for me, and I’d like to keep doing it. It allows me to practice doing challenging things, tolerating a bit of discomfort, setting goals and achieving them, and I love the sounds and smells and visuals of being out in the mountains.
This morning I went for my first hike since starting this program, and I purposefully chose one that’s shorter and less strenuous, knowing that my body’s still adapting to fat-burning. (I’ve only been on protocol for 5 days). It was far harder than usual, to the point where I found myself steadying myself against a railing or a tree and waiting for the lights to come back on. I managed it, and I still enjoyed it (though it will be much more enjoyable when I’m more fit), but it was a bit of a shock. Before adopting my protocol, my habit was to have a protein shake (high protein, less than 4g sugar) before a hike, but I did not do so this morning because I was still in my fasting window.
It seems my options are as follows: (1) Give it a week or two and see how it feels once my body has adapted to fat-burning, and expect it to be harder until then and be extra cautious, or (2) Change my eating window so that I can have something in the morning to fuel my hikes. (I generally hike twice a week, early in the morning).
What would you advise? Thanks!