Is there a way to ease or eliminate a post-ride glucose crash? Either by switching what I use to fuel my rides or if I need to change how I time my carb intake?
I’ve been tracking my migraines and have linked them with glucose consumption. For long rides, I have been using home-brew mix (50/50ish maltodextrine/sugar + table salt) at about 60g/hr carbs (I’m 180lb/80kg) and would bump it up if I was in a race. I’d continuously drink it throughout the ride all the way to the end. 6 hours later, I’ll have a migraine. I noticed the same thing happens if I consume a large amount of sugar off the bike (it’s candy corn season).
I follow these rides with a good post-ride meal and hydration for the rest of the day. I track calorie consumption to avoid calorie deficits on high mileage days. It doesn’t really have an impact on the headache outcome.
Has anyone here experienced anything similar and found a better way to fuel long rides? Would a longer-burning carbohydrate source do anything to smooth it out? Should I taper off the carb binge? About the only thing I’ve tried that works consistently is just not fueling rides and limiting them to 90 minutes to avoid a bonk.
I have read up on fat-adaptive training and it’s not for me.
I don’t know if this will help at all, but I occasionally get migraines as well. I get them seldom enough that I can’t really track exactly what causes them (they occur once every few months). But, from what I can tell, my migraines appear when I don’t fuel enough. For example I’ll have a few big days in a row, get in a calorie deficit and then I’ll get woken up in the middle of the night with a migraine. When I’m diligent about getting carbs in while riding they rarely if ever happen.
Sounds like your situation is opposite of mine for some reason. Are you pretty confident you’re not in a deficit, including previous days and off the bike calorie burn?
This helps me not feel like crap after long rides. I try to eat solid food along with all the quick acting sugars. A bit of protein helps. My go to are peanut butter filled pretzels. Peanut butter cliff bars ( yes I’m old and grew up racing on them and gu. ) Bananas . Sometimes rice cakes.
I do get headaches when I fast, so it might be a similar situation. Those headaches usually respond well to eating food and taking ibuprofen, though. The post-ride crash headaches are untouchable unless I take ubregopant or some other migraine-specific prescription.
I’m pretty strict about not running a big caloric deficit, so I’m reasonably confident. If there’s a deficit, it’ll be because I miscalculated something.
Dingo - if you are at 60g/hr - Complications after a long ride would much more likely be due to low glucose - as you were definitely never positive… no sugar crash… besides the fact you are low… so really a bonk.
Often when I go on long runs or rides - the hours after can be a bit funky (no headaches, but floaty) lol sometimes its hard to know if overheated, bonky or dehydrated…
Unless you are a small person, very low FTP, and/or riding at a VERY low % of your FTP (burning almost all fat or just very low total kj ride)… your muscles are sucking up that fuel faster than you can supply it (240cal / hr), short cutting anything to do with liver/insulin. Run the numbers… what is your kj per hour?! Unless you are below 500cal/hr burn AND riding <60% ftp without any surges above 61%…
Try a high carb drink with protein right when you get home, 1.2g carb / kg plus 20g protein, plus a good amount of sodium (600-1000mg).
The TR guideline of sorts has been that the preride meal, on bike fuel and immediate recovery shake should equal the total of the rides burn… how close are you to that? A few stats or example rides of total intake (in the 2hrs before… during… and shortly after ride), ride info (power, duration, zone%'s) and FTP / rider size.
I think blood sugar and fueling - overall symptoms are tricky, especially for sensitive individuals. Similar to hydration… over and under … leads to very similar symptoms! Luckily for most people and doing longer rides - over is pretty much impossible unless rider is small and/or low FTP… even then stomach distress will limit ‘over fueling’ most likely before their energy balance is positive.
Actually, looking at the numbers, it’s close to 50g/hr. A 4 hr ride at Z2 was about 720 kcal/hr, so 2,880 kcal burned and about 800 kcal fueled. Pre-ride (oatmeal) is about 450 kcal, less than an hour before the ride (early AM, usually start before dawn). Recovery right after I got home and showered my typical recovery meal (2 tamales, 3 scrambled eggs, small carton of protein drink, LMNT) would be about 1200 kcal (~50 g protein, ~80 g carbs), within 30-45 minutes of being off the bike. So, still low, but not in a crazy deficit.
I sweat excessively, so that was another challenge to figure out. Hydration pack + 2 bottles of mix on the bike, and I still lose ~2-4 lbs of water weight on a long ride.
Numbers-wise, I agree with you. But the migraines hit ~6hrs after I’ve finished a ride in which I fueled with drink mix. The same migraine, same symptoms and response to Rx and all, happen ~6hr I binge on candy, but without the exercise-related drop in glucose and dehydration. If it wasn’t for that correlation, I’d be saying the exact same thing you are. There’s still a chance that these are two coincidentally similar pathways to triggering a migraine. I’m trying to figure out a reliable way to rule that out one way or another.
I appreciate the critical input. I do need to keep from forcing myself into arranging the data into fitting my conclusions.
Apparently Exercised-Induced Appetite Suppression (EIAS) is a thing. I also get headaches when I don’t eat following big workouts. I also get a sugar crash if I don’t eat soon enough after a bike. I’ve found that a recovery drink / shake helps with both. Really just need to have it in the fridge, ready to go.
What about the rest of the day’s nutrition? sounds like you may be around a 500cal deficit after your post ride meal, but you’d still need an additional 2500 or so just for normal life. Are you eating 3000cals for dinner/snacks for the rest of the day?
Headaches are generally underfueling and/or hydration & electrolyte related for me, especially on long rides. If you sweat a lot, then I am leaning towards a combination of all three. More sugar on the ride, and more sugar after.
This is 75% glucose and 25% fructose by the way, or a 3:1 ratio which is very heavy on the glucose. I use a 1 : 0.8 ratio which is closer to a mix of 90% table sugar and 10% maltodextrin.
If the glucose is triggering the headaches, reducuing the glucose and increasing the fructose may help while givnig you more total carbs.
Good point BenB on rest of day calories - depending on your source of calorie burn… it might just be using the kJ burn from power meter. Meanwhile you missed lunch… most likely… also burning your basal metabolic rate for that 4hrs also. One reason I do like how Garmin presents Calorie Total, Calorie Active and Calorie Rest… for each workout. Not that big of a deal for 60-90min workouts Total and Active are nearly the same. But once you get over 3-4hrs it starts to come into play, your refuel meal… also really is just the meal you would have had if resting ALL day (besides the shake)! So for that 4hr ride, likely should have had a recovery lunch… then another actual ‘rest day’ lunch 2hrs later lol
Yep. That’s actually the main reason I started tracking calories daily. If I’m still short after dinner, I’ll make up the remaining calories with ice cream and a homemade protein shake.
I’m glad you mentioned this. I originally interpreted the ratio as sugar:maltodextrin and not glucose:fructose, which is wrong and I kept meaning to fix my recipe. It’s cheap enough I can mix up a new batch and experiment. Thank you.
I’d target 100g/hr, or work your way towards it. All my rides range from 1.5-5 hrs typically. Virtually every one gets 100g/hr. Still has me finishing in approx a 300 cal/hr deficit.
Just a note on the high carb tendency, I know it’s becoming de rigeur but numerous studies referenced in a recent fast talk podcast, suggest it isn’t correlated very highly to increased performance and may be more likely to result in gastric distress. It’s highly individual and even high performance athletes may only be utilising relatively modest amounts of carbohydrates (30-60g), see gcn vid where they gave Connor 120g per hour for 2hr steady state but he only oxidised 46g per hour. Specimens like tadei etc are using 120g due to a niche ability to run glycolytically, shuttle lactate and oxidise carbs, whilst having the ability to rely on fat at crazy outputs so speed is just insane.
It’s an individual thing that needs to be experimented with, and trained if you do have a higher carb usage capacity.
This is trainable, but most only develop the glycolytic side and as a result overly rely on sugar intake. The highest fat oxidation seen when measured is 2g/min or 120g/hour ~ 1080 kcal an hour from fat and not just at low intensity either.
