Thanks, just seems since I started last week I don't can't keep up after 10 minutes when previously this wasn't an issue and Saturday I struggled to finish averaging under 200w when normally it would be 250. I know a month of no riding in December won't have helped either.....
Its far too early to expect performance whilst adapting to a low/er carb regime. I think it took me several months to be able to race whilst fasted. Listening to all the comments, expect your body to take 2-4 weeks to become fat metabolic adapted.
From there build up your intensity and duration of exercise. Don't be afraid to use carbs
whilst training, especially high intensity.
Use proteins and fats to replenish directly after a period of high intensity. I use Whey isolate directly after a race or workout. I usually consume eggs/ bacon, cheese as my staple energy sources, which are next to zero carbs and will keep you in ketosis- if that is your aim.