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@Nick.Earthloop
#workupto500 September 425
My 425km ride in September was supposed to be a ride home from Devon, but that trip got cancelled so I cobbled together a last minute route to Bradford and back.
On recent long rides my mantra has been Eat All Of The Sugar Now, but this time I tried something completely different. Since the start of September I've been on a low carb (~ 25g per day) high fat diet, with my 55km per day of commuting fuelled by fat and maybe some ketones; I peed on a ketone detecting strip and it said "yes, lots" but those things can be unreliable.
Breakfast: salmon and soft cheese, coffee with cream. On the road: almonds, cheese, biltong, droewors. Electrolytes only in the water bottles. 50mg per hour of caffeine in the morning, stopping at noon.
For the first 8 hours everything felt fine, except for a bit of stomach pain if I ate the cheese too fast or didn't take enough water with the droewors. At the 8 hour mark I'd covered 225km, a distance that normally takes me 9 hours elapsed.
Then I think my blood sugar started to drop, and by the 9:15 mark I was well into a bonk. I'd slowed right down, I was unable to spin to up to 90 even on the flat in a very easy gear, and my primary thought process was "cycling can fuck off". My emergency energy gel perked me right up, and I followed it up with 30g of dextrose over the next hour. I felt better, but didn't regain the pace I'd hit in the first 8 hours.
At the 11:45 mark I felt the early signs of the next bonk, so I added my remaining 60g of dextrose to my water and bought some jelly babies at the next garage. I perked up again, but continued to gradually lose the extra hour that I'd banked during the first part of the ride.
By my rough calculations, that means I burn about 20 to 30 g/hour of carb, and my body had about 225g of carb stored when I set off. Next time, I'll add a small amount of carb to the road food.
The next day, legs properly wrecked. During the later part of the first 8 hours (A4, no twists and turns, just pounding out the miles) my heart rate was hovering around 150 to 155 and I was comfortable maintaining that. At 160 I start the heavy breathing. Maybe the higher than usual caffeine dose on this ride caused me to be comfortable at too hard a pace during those hours and wreck my legs and burn more carb than I otherwise would, or maybe it was the bonking that wrecked the legs, or maybe they just need to HTFU. Further experimentation is needed.
http://www.strava.com/activities/200934112