Why'd I bonk?
 

Hey folks,

I bit off more than I could chew yesterday trying to up my endurance for long rides, and I'd love anybody's two cents on what the hell happened and why. The ride was 71 miles with 5700 ft of gain, climbing Old La Honda up over to the mighty blue Pacific, and then Tunitas Creek Road to get up back over to the bay. Epic stuff in my book. I had previously done the bulk of the hard part of this ride (the middle 40 miles with 4300 ft gain) twice on previous recent weekends, and felt good enough after the second time to give this a go. And hey, I made it. Nice.

Unfortunately, it wasn't all ...the nicest. I found out what bonking is all about when I was maybe half way up Tunitas. I had to stop maybe five times and just hydrate, eat some bar and stare at the ground like a zombie for several minutes. I felt like I had zero energy to push my legs forward. I was maybe vaguely nauseous, but basically just spent. I rode the whole rest of the hill VERY slowly, in stages with breaks, and feeling pretty damn demoralized. Shout out to all the friendly riders who asked to make sure I was okay as they cruised on by. And I'm glad to say that I was able to rally and ride at least functionally for the final 20 miles home from the top.

Thing is, replaying it all in my head, I'm still unclear what happened. Here's the facts of the case:

• I didn't carboload for multiple days or anything, but I did intentionally eat some extra carbs the previous day. Consciously hydrated more than usual that evening too.
• I ate three packets of oatmeal and a banana for breakfast, maybe like half an hour before heading out. Also sipped plenty of water while I was getting things ready.
• I filled two 22 oz bottles and popped one and a half nuun tablets in each. Then I refilled these (and added more nuun tabs) just before the Tunitas climb (gotta love that bike hut.) So all together, at the time of The Incident about 3:15 into my ride, I'd polished off more than two liters of water, all of which had electrolytes mixed in. This felt like plenty for the intensity of my riding and the weather conditions, and if anything probably more hydrating than normal for me. I am definitely a heavier sweater than your average rider.
• Over the course of those threeish hours, I ate two SIS gels (maybe 180 cal) and 1.5 clif bars (maybe 350 cal,) ballpark total 530 calories. Given the significant breakfast and the fact that I'd only been out there for three hours, I definitely felt like I was consuming enough fuel.
• It heated up to be a hot day, but much of my ride was upper 60s/low 70s and shaded. There was one stretch on the coast with an exposed 400ft, 10-ish minute climb, but that was really the only time I felt like I was getting any intense heat on me.
• I'm 6ft, maybe 195, been on a road bike (trek domane) for about 2 years.

So yeah. I don't think I clearly underfueled or underhydrated. I will say that I suspect it was a hydration issue somehow anyway, because on the long ride home I had some significant cramping in my thighs and noticed I really wasn't sweating as much as normal.


Any thoughts? Am I just off on my conception of what's necessary in terms of hydration and/or fuel for this kind of ride? Or just a wuss?

I bit off more than I could chew yesterday.............

That says it all. I think you need to work up to something like that with better training etc. Mild nauseous is not a good sign. Could be from heat, overexertion, or both but your body just told you too much right now. Not a food or hydration issue. You can't eat or drink your way to fitness. IMHO you had plenty of both for this ride. Maybe better, more measured water intake. Do you sip water every 15 minutes or so or do you wait and chug?

I think you just rode beyond your limit.

Tunitas will do that to you. I have seen so many people suffer in that steep middle section, and I've experience it myself a few times. Welcome to the club.

I do a 53 mile, 5400' ride from Palo Alto up Kings Mountain, down Tunitas, right on Lobitos Creek, left on Highway 1, left on Tunitas.

Sometimes I feel great, sometimes I suffer in that steep section of Tunitas.

Yeah I mean it seems like it was a reasonable progression from what I've been doing. I've done these two climbs in tandem before, twice in the preceding three weeks. The only difference yesterday (up to the time of the bonk) was the relatively easy miles 17 miles/ 700 ft I rode out to start those climbs. Thanks for the feedback, I can definitely try to be more mindful of how I pace the hydration. I just finally made the switch from camelbak to bottles recently, still getting used to it.

I don't think you gave yourself enough time to get the oatmeal and banana digesting before you hit the road. Try eating the oatmeal 2 hours before you hit the road next time, and eating the banana about 30 minutes before you start riding.

Sounds more like riding beyond your fitness than a nutrition issue. With 530 Cals in 3 hrs you could eat a little more but it likely wouldn't have helped.

How many hours are you riding during the week? A powermeter would help determine how big the effort was relative to other rides.

It could be as simple as you were just going too hard during the 3 hrs. As your fitness improves your body will utilize a higher % of fat for it's energy needs. If you're riding close to your threshold most of your energy will be coming from carbs and given that you're a pretty big rider it's not unexpected that you could exhaust your available carbs in a little over 3 hrs.

Most likely not hydration, not weather, not food, not fitness. That would leave pacing, maybe you went out too hard at the beginning and tore through your reserves too soon, thus they were not there when you needed them on a very tough climb. BTDT. Twice this summer, got stuck in the middle of nowhere, felt like I was gonna die (running out of water and being out of cell phone range in 100 degree weather did not help either).

Maybe gearing, did you feel like you had enough gears?

These perspectives are all helpful, thanks. My pace wasn't out of my standard ability, but I think my next goal is going to be to do this ride at a deliberately slow pace, with no other objective than to get through it smoothly and enjoy the scenery. Then onward & upward from there.

Bonk happens.

You didn't bonk; you're just not in shape for that type of activity. The cramping was also likely due to that rather than hydration. Keep plugging away and you'll be able to handle it better in the future.

A true bonk is really unlike anything else. I mean, it can be bad enough where there's not enough energy to get off the bike sometimes. And then, 10 minutes after eating something, there is. It's pretty wild.

That's a good tactic.

Wow. What an awesome ride. 30 or so years ago I lived in Redwood City, and that was my favorite area to ride, though never did that big a loop!

Sounds to me like you paced a 70-miler as you would a 40-miler, and your body wasn't having it.

Endurance conditioning comes with miles ridden. If you haven't spent much time up past 50 miles, those miles can get rough, regardless of your health or the weather.

When I start hearing Tour de France music in my head, and improvising Phil Ligget dialog, and feeling like I'm just crushing it that day, but I'm only 10 miles into a long day in the saddle, it can be tough to back off. I'm terrible at this myself, I often over estimate my fitness, and how long my food and water will last. Long rides are not really my specialty, most of the fun is over for me by about the 3rd or 4th hour anyway. And I've probably gotten most of the alleged health benefits of the ride by then too.

At least you had other riders around had you had some sort of medical emergency, it can be scary to have that happen to you in an exposed location miles from anyone else.

1) Give your pre-ride nutrition more time to digest and get into your system.

2) What have your rides been like up to this one? I’d you don’t normally do a fair amount of climbing maybe this was just too much right now. Build up to it next time to the point where you’ve done several rides of 70-80% distance and elevation as the one you want to do. Plus some of the same or longer distance but flatter where you push it hard. Then you’ll be more ready for the longer climbier ride.

Was going to guess the heat got to you but then you said the temps weren’t that bad

None of us can be in our best shape each and every day. Some days i can't even find the strength to get out of bed. When you are over 30, it is all right :)

Someone asked about your gearing. I'm a little heavier than you (and probably a lot older) and I need low gears for climbing. I use a 34x29 for about everything.
I also sweat a lot and I have to force myself to drink enough and if it's a hot climbing ride I can't keep up. I get nausea when I get dehydrated. I have drank over 200 ounces of liquid on 7-8 hour rides.


When I do climbing rides I weigh myself before and after which gives me an idea of my hydration loss. I have come home 11 pounds lighter, 5 or 6 pounds is about normal. You can also check the color of your urine. If it gets super dark and doesn't happen very often, you are dehydrated. A few weeks ago I didn't pee after the ride until late that night.

A lot of this stuff is just learning your body and how it responds to what you are doing to it.

IME having to stop multiple times on a climb and not feeling well is not a training volume/intensity issue. What you get in that case is mostly excruciating pain in the back/quads/hams/calves/triceps/ etc., which may or may not lead to cramping on the climb. In those cases, I've always been able to just keep riding, understanding that I was moving my perception of a pain threshold to a new level. That feeling of just can't turn the cranks is an energy problem, i.e. low blood sugar from some cause. The usual cause is what I call "sloshy stomach," meaning the feeling that one's stomach has contents, but they don't move. So my guess is some variation on that. What one does in that case - the case that you've feel you've eaten plenty but can't ride - is keep drinking water until you feel better, sometimes lots of water. You have to get the stomach osmolality down. So being a little dehydrated can be how this might start. Conventional wisdom among randonneurs is: whenever you feel down, discouraged, having trouble keeping going - EAT! (and drink).

On a serious ride like this, at least serious for you, eat 3 hours before the ride, then nothing. During the ride, try to eat no more than ~50 calories every 15'. Start eating like that from the start. Never stop eating for more than 1/2 hour. You were probably eating enough, but maybe too much bolus and not enough dribble. Once you start with the gels, you have to keep them coming. They're quick energy and quick gone, which is fine, but you have to realize that, and realize that gels take a lot of water per gel, say 6 big swallows.

Edit: as others have said, this is not a bonk. It's just low BS.

Re hydration: how often did you pee? My metric is pee every 3 hours. If I don't, I'm dehydrated and I'll sit and drink until I do. The late ride cramping is probably from overdoing it a bit. That's normal. The dry skin is not normal - you were dehydrated. When you feel that, it's late in the game and you're not far from becoming a medical emergency. Sit and drink plenty of water ASAP along with electrolytes.

During a ride like this, you should feel a little thirsty all the time. If you don't feel like drinking, you aren't using enough electrolytes. OTOH if you are really thirsty and are thus drinking and peeing too often, you are using too many electrolytes. The balance is quite tricky and thus I always separate my water and electrolytes.

Sometimes these things happen. You can hit the Wall in a marathon and still be in fantastic shape. Many factors don’t beat yourself up. I have sort of bonked riding but I have hit the Wall in a marathon, that is not nice. Lucky for me is was in last mile of marathon. I finished fine but could not stand up for 25 minutes after the race. Someone gave me a real coke not diet, I was a completely different person in 10 minutes. Got up and could move fine.

I had a bonk one morning back in August during a heat wave. I was riding early morning with a friend who is a strong rider. My normal fuel and fluid routine. I did not feel right from the beginning but tried to push through it. I requested a stop in some shade for a couple of minutes a couple of times. 26 miles in, and 6 miles from home, I felt like I just could not push the pedals anymore, feeling so bad I did not think I would be able to finish. We stopped for about 10 minutes in the shade and I sipped water the whole time. I started to feel a bit better and, fortunately, we had a tail wind the last 6 to home. Once at home, my friend rode on to get himself home, I got some cold apple juice and a p and j sandwich. I sat down in my recliner and next thing I woke up just over an hour later, feeling alright but a bit groggy. I did not figure out what happened until the next day. I was checking my email and there was a thank you message from the local blood bank for the double red blood cells I had given 5 days earlier. Well crap, no wonder I had that episode. I had totally forgotten about it. I will not repeat that mistake.

Lot's of good points all around.

On gearing: I don't think this is my issue; I've climbed this hill three other times in the last 5ish weeks, and felt increasingly confident on it using the gearing I have. Long, tough climb for me but no stops or notable issues.

On pacing: surely something I need to take more seriously. The first climb of the day was Old La Honda, where I was only a minute behind my PR. That's probably just a bone-headed way to start a 70 mile day, given I've never ridden more than 50ish on a single ride previously.

On fuel: I guess I need to get my ass out of bed and get started on digesting breakfast earlier. I think I probably did okayish in terms of the fuel I ate on the ride and how I paced it out, but maybe could get in a better rhythm of frequent fueling.

On hydration: my first pee was hours after my ride, and was moderately yellow. I'm surprised to say it, given how much I drank and how it compares to how much I usually drink on a hard ride, but I think dehydration definitely came in to play here. I wonder if my time in the sun on the coast took more out of me than I realized. I'm probably just a guy who needs more than the standard recommended amount of water for these types of distances. Like I said, I'm a sweater.

On what was actually going on during that hour of fail: I think what Carbonfiberboy is describing about a low blood sugar event pretty much nails the experience I was having. I am still curious about what you guys mean when you distinguish between this and a bonk. When I google bonking, the internets seem to be generally describing bonking as relating to glycogen storage and hypoglycemia. I guess you're distinguishing between general hypoglycemia and the more specific immediate event of depleted glycogen stores in the leg muscles? I'd be curious if anyone wants to clarify that further. Either way, I was pretty damn useless! But basically, once I got back down to Woodside to fill my bottles again, I was able to get something going again by doing exactly what Carbonfiberboy recommended: rest and hydrate until my legs didn't feel completely worthless any more.

I think that's a good strategy. When I try a tough route for the first time, I make a conscious effort to do all the climbs at a moderate pace.

Today I climbed West Alpine for the first time in ages, so I could check it off my list of "climbs that scare me". I took it easy. It was tough in spots where the grade was 10-14%, but it didn't wipe me out.

EDIT: And regarding feeling sick during a ride, maybe my experiences can help. I recall all the events when I felt like I had a bad case of the flu. The causes differed, but the sensation was the same:

1. Dehydration, usually on hot rides--but not always. I felt awful after the Muholland Challenge, even though it was cool weather, because I rode the last 25 miles without water (last rest station wasn't open when I got there).

2. High temperature. Climbing the back side of Mount Hamilton when it was over 110º in the shade (but there was no shade).

3. Hyponatremia (inadequate sodium). Managed that trick at Climb to Kaiser on a record hot day. I drank lots but didn't take in enough salt. Ended up in the emergency room.

A couple of comments.

1. Once you hit mild dehydration, which is the normal steady state during a long, hot, ride, urine production decreases and what you make is concentrated, as the kidney starts to conserve water and sodium. It’s normal. Go for colorless urine at home. If you try that on the bike, you’ll have to stop every 20 min and risk a public urination charge.

2. The symptoms you describe could be due to hypoglycemia, hyponatremia, or dehydration, so it’s hard to say what happened. You start a ride with about 90 min of glycogen in muscle and liver. After that’s gone, muscle consumes other substrates, i.e. ketone bodies from fat catabolism, and glucose from gluconeogenesis—generation of glucose from various compounds, including lactate and amino acids, and, of course, whatever you take in by mouth. As I understand it, endurance training is a process of upregulating and optimizing those secondary energy production mechanisms. If you outride them, you have to eat carbs. Lots of carbs. According to my understanding of the term, “bonk” is an energy crash occurring when intake doesn’t keep up with requirements and lack of endurance training just makes it happen earlier.

BTW, this sounds like a pretty major effort and my hat’s off to you for completing it!

How often do you ride with the intensity and duration, as you did on the bonk ride ?

So, I've been good about getting in the saddle about three times per week since the Spring (less consistent during the darker months, but I try to compensate on an indoor trainer.) My weekday rides (twice per week) are usually in the low twenties mileage-wise, with some decent climbing that usually brings them to around 1600 feet of gain. Then I've generally been getting a longer third ride on the weekend. Two of the recent ones were basically the big middle portion of this longer ride (the middle 40 miles, with both the major climbs for 4300 ft gain.) Others have been all over the map but probably averaging 40 miles, with the longest being 51 miles and 4000 ft back in early August.

This was obviously a notable leap, but after I finished that "middle 40 miles" ride again last weekend, I could tell I had more gas in the tank. So I figured I could survive adding the 30 less hilly miles that would make it an out and back from my garage. And I mean I did make it, if not so gracefully. But I don't feel overly sore now 36 hours later and I'll probably do a moderate ride this afternoon.

Any advice from how someone got from here to comfortably handling longer endurance rides would be appreciated. I'm 34, not a particularly athletic guy, and I've got some extra pounds on me for sure. But I'm pretty capable of pushing myself, and my climbing times have been getting consistently faster (current Old La Honda PR 28:56 as a benchmark.) I know the biggest advice people are going to give me is TITS and expanding those weeknight rides to longer distances, but I only have so much time to spend on the road (and my schedule is undoubtedly going to falter as we tilt into the Winter months, too.) And I don't think 70 mile rides are only for wiry guys who ride 50 miles a day... I envy all the older dudes I meet out there who seem to have locked in the ability to go for a nice long Saturday morning ride at a nice reasonable pace without completely arranging their lives around cycling.

I'm 65 and one thing older dudes like me have is a "base" or "miles in the bank" as we say. I'm also over 200 pounds and I like climbing, even though the wiry guys have to wait for me. At my size I will NEVER be a fast climber but I can still have fun with it.
I've done 12,000 foot centuries and lots of long climbing rides, the key is to just keep riding as much as you can.
When I was 35 I joined a road club and started doing centuries every Saturday. Not so much anymore but I know I can still do one.