Nutrition while on the Bike

I have generally not been eating on any of my TR workouts even thought I am on mid-volume, SS Base 1 plan and moving to SS B2 in two weeks. I train 5-7 hours per week, with TSS between 425-500 each week. Longest indoor rides have been 90 minutes but I occasionally supplement with outdoor rides also.
As the intensity of the workouts has increased I am now doing over/unders at 95-105% of FTP over 60-75 minutes and this weekend had a 90 minute workout with 3 x 20 minute intervals at 89-94% the entire interval with 5 minutes of rest between intervals. I have not been eating and only drinking water during all of my workouts and yesterday felt fine during workout but after eating felt sick being dizzy and just not feeling well though out the day. I am now beginning to think I need to eat during all of my TR workouts at least 50-60 grams of carbs each hour I am on the bike. I am a healthy male, 65 years old, 5’ 6 at 125 pounds with a power to weight ratio of 3.4, so pretty small but all muscle and very little body fat. Does anyone else have experience with this and does eating during the rides help you feel better not only during the workout but also after the ride? thanks.

If you’ve completed all of Sweet Spot Base 1 and only experienced this once, then I wouldn’t suddenly look at making dramatic changes. There’s any number of things that may have caused what you experienced.

I don’t see any real downsides to adding extra carbs, but don’t necessarily assume that this is the cause of your one-off experience.

Thanks. I will experiment with adding some carbs, 40-50 grams per hour and see how I feel.