Absolutely. When I'm following a ketogenic meal plan, my baseline endurance shoots through the roof. I can walk/bike/whatever for hours. However, I do lose sprint performance.

As I'm in my 40s, and just exercise for fun and the health benefits, this is a tradeoff I'm more than happy to make. I'd much rather be able to cycle for another 10 miles without thinking about it than to increase my pace from 12 to 14 mph. But it is something to be aware of.