I know this has been posted before, but I did not see any good answers.
I am a fairly experienced city cyclist. I ride almost daily as a commuter (5 years), and would like to do some longer distance riding. From time to time I experience headaches/nausea and fatigue after going for a longer rides (+40km). It is really important to me to build up to longer distance riding and maybe do brevets next year.
I am hoping someone can provide some input.
Some stats about me:
40 years old (lost 35lbs in the last 5 years)
35 lbs overweight
blood pressure fine,
sometimes hypoglycemic (yes, I actually measure it from time to time)
This past Monday I went out for a long ride about 50km, and suffered the exact same headache/nausea that I experienced several years ago in the MS 150. Last time I thought it might be heat related, but I was riding in +6C (40s F) on Monday. Of course I was soaked in sweat, and a little cold by the time I got home, but not overheated.
Ride Length: 50km (30 miles)
Drank: 2L of juice/water, 1 tea
Ate: Energy Bar, Two Apples, Bagel and Cream Cheese
Had a small nap after I rode, still didn't feel any better. Overnight sleep of 9h seemed to do the trick, as it did last time. Symptoms did not onset until about 1/2h of stopping activity.
So, places I have thought of looking:
Although last blood test showed nothing irregular.
From time to time I can be hypoglycemic, but I felt I ate enough good food not to be (oatmeal, energy bar etc)
I drank quite a bit, and my urine after the ride was not dark at all. I also drank lots of water once I finished the ride.
Oxygen depletion (yes, I am quitting)
Because I am a smoker, I may not have the lung capacity to deliver enough oxygen, although you would think the headache onset would happen during the ride, not an hour after.