Ultimate Bonk Ride | What Happens When You Cycle 140km Without Eating?

Most cyclists will have experienced the dreaded bonk while riding, be it because you forget to eat, or go out for longer than you thought, the feeling of being absolutely empty is universal. So why would you want to go and do that on purpose? Conor decides that he’s willing to do it in the name of GCN science, to find out what happens to your blood glucose levels if you go on a hilly 140km ride with Hank through the Brecon Beacons, without eating. As if that’s not gruelling enough, Hank and Conor compare power data for a series of 5 minute intervals over the course of the ride!
Visit the GCN Shop - Shop Now: gcn.eu/5yL
Subscribe to GCN: gcn.eu/Subscrib...
#Cycling #GCN #RoadBike
Have you ever bonked? Tell us your experiences in the comments 👇
Sign up to the GCN newsletter gcn.eu/3K7
Join our Facebook community: gcn.eu/FBCommunity
If you enjoyed this video, make sure to give it a thumbs up and share it with your friends. 👍
Watch more on GCN...
📹 A Decade Of Evolution | 6 Ways Cycling Has Changed In The Last 10 Years - gcn.eu/5yH
Music - licensed by Epidemic Sound:
Swish 2.wav
Swish 1.wav
ES_Warmer Waters - Stray Bandit.wav
ES_Wake up, It's Time to Go - Ava Low.wav
ES_Told You - White Drift.wav
ES_The Mole - Christoffer Moe Ditlevsen.wav
ES_Pylons - Mochas.wav
ES_Strange Behaviour - Luwaks.wav
ES_Park Lake - SFX Producer.wav
ES_Keflavik - Mochas.wav
ES_Habitual - Ava Low.wav
ES_Dust and Heat - Segmental.wav
ES_Amun Ra - Bureaucrap.wav
ES_2 - Rospigg.wav
Photos: © Velo Collection (TDW) / Getty Images & © Bettiniphoto / www.bettiniphot...
The Global Cycling Network (GCN) is the largest and fastest-growing online cycling channel in the world, bringing together a global community of road cyclists to celebrate everything that’s great about the world of cycling.
Our videos bring fans compelling daily content including expert tutorials, techniques, training, racing, cutting-edge bike tech, unparalleled behind the scenes event coverage, humour, entertainment, and more.
Presented by ex-pro riders, GCN offers a uniquely qualified insight into the world of cycling, and most importantly it’s fuelled by our passionate and enthusiastic fans - everyone who makes up the GCN community. We also bring you the latest and greatest tech to your attention, showcase the best places in the world to ride and get exclusive access to events and races.
Welcome to the Global Cycling Network | Inside #cycling
Thanks to our sponsors:
Castelli Clothing gcn.eu/Castelli
Giro Helmets gcn.eu/Giro
Pinarello Bikes gcn.eu/Pinarello
Zipp Wheels: gcn.eu/Zipp
Enervit Nutrition: gcn.eu/Enervit
Topeak Tools: gcn.eu/Topeak
Canyon Bikes: gcn.eu/-Canyon
Pirelli Tyres: gcn.eu/Pirelli
Orbea Bikes: gcn.eu/Orbea
Vision Wheels: gcn.eu/Vision
Wahoo Fitness: gcn.eu/Wahoo-Fi...
Park Tool: gcn.eu/-parktool
Elite Bottles: gcn.eu/EliteBo...
Whoop Fitness: gcn.eu/Whoop
Komoot: gcn.eu/komoot
Selle Italia: gcn.eu/SelleIt...
Zwift: gcn.eu/Zwift
GCN Japan: gcn.eu/subscri...
GCN Italia: gcn.eu/GCN-Italia
Suscribirse a GCN en Español: gcn.eu/Suscribirse
The GCN Club - gcn.eu/club
KZbin Channel - gcn.eu/gcnYT
Facebook - gcn.eu/gcnFb
Instagram - gcn.eu/GCNInsta
Twitter - gcn.eu/gcnTW
GMBN Tech - gmbn.tech/subsc...
GCN Tech - gcntech.co/subs...
EMBN - embn.me/subscribe
Leave us a comment below!

[@gcn]

Have you ever bonked? Tell us your experiences in the comments 👇

[@jangold4652]

Yikes 1like haha

[@supernoodles908]

Worst I've bonked was in a swimming session. I had trained 23ish hours so far that week and the coach gave me an evil mainset. 50x200m and I'd roughly get 5-10 seconds rest between each one. I was basically swimming non stop without food for ages... I just hit a wall. I kept pushing. Kept telling my body to go but it just wasn't having it. Probably not the most physically effective training session but great for mental strength

[@oisinkyne1469]

Proud to say i never have, I never cycle more than 50k but thats not important

[@hambernat6444]

When I was started cycling this was my first month of riding more more than 50km per week. I did on MTB 112km before first grocery store & then I have to ride second 112km to my house.

[@DutchBicycleCam]

yes many times before i watched GCN.

[@BrownianMotionPicture]

The worst thing about falling flat like this is getting overtaken by anyone and everyone, just knowing you'll be part of Daves pub story about how he overtook a roadie on his £99 argos pavement bike.

[@deivytrajan]

Lmaooo

[@DinnerForkTongue]

If you don't want that to happen, don't bonk. Pretty simple.

[@KristopherNoronha]

I think he still did better than at least 90% of all fully carb'd cyclists out there :D

[@elizabethr9304]

oh man... I've never thought about it like that!

[@kishascape]

True but everyone knows people with stories like that are wankers. We joke about them behind their backs.

[@ap5194]

I bonked a few weeks back, could barely turn the crank on the last mile. The worst part was all the horrible thoughts 😂 thought about my whole life over and over and stuff I'd done wrong. Then ate a Mars bar and all was fine 👍🏻

[@billincolumbia]

Same here. Just the worst possible thoughts in my head.

[@koolfy]

Omg! Me too!

[@aemiliadelroba4022]

I know the feeling , same thing happened to me … scary 😧 when you can’t even pedal the bike 🚴.

[@jodiemcclellan5771]

🤣🤣made me laugh this🤣🤣 your spot on aswell

[@RealityCheckTime]

I wish I could just ate a Mars and be fine when this happens. I'm afraid I'm not!

[@Samuelclark11]

*Connor gets cocky with his recent power numbers - GCN writers: “Lets wipe that smile off his face

[@davidburgess741]

He admits to coming up with the idea! Alas, he didn't drop!

[@nicothedj]

Conor: "Would not recommend doing this...would not" Me realizing that I do this every ride

[@g.west2372]

did 100km last time and it started to really hurt after 70km... shortcut another hill to get home? no i still got half a fruity-bar so lets go! on the last 10km every small hill (beeing fresh you wouldn't even count them as hills) pushed me to the max...

[@johnnybow7045]

I did a 240k ride once. Until 100k I only ate a banana, two snickers bars and an apple. Also I was clever to attempt it on a Sunday with only gas stations open. Still ask myself how I did it in the end

[@AkshatSTR8EDGE]

@@johnnybow7045 the two snickers bar surely helped alot.

[@red00tl]

Chapeau to Connor for his dedication to science, his willingness to starve while riding 140km, climbing nearly 3,000m, AND drawing blood every so often throughout his ordeal. 😱👍😭

[@gcn]

He's dedicated!

[@GelMibson-u2y]

It’s still rather do that than Hanks 24hour zwift

[@Arfonfree]

Looked like they were using glucose monitors, not drawing blood.

[@Ben-yr9jo]

at minute 20:00 you can see the little disk on Hank's upper arm, right around the triceps, that's the Glucose monitor module, it's connected to their phones so you there's no need to draw blood. Even with conventional methods, measuring blood sugar is really just a tiny poke, there isn't any blood lost in the process.

[@blu0065]

@@Ben-yr9jo so it's an abott CGM, probably

[@dougarch]

‘He’s like a bloody glucose camel’ 😂😂😂 Connor’s new spirit animal?

[@thomasschumann4034]

"If I tried this earlier in my cycling career, I would have bonked way earlier" - Conor *Later GCN on the phone with Freddy "Freddy, we've got a new challenge for you, you're going to love it"

[@ridinghome4988]

And Freddy will once again surprise everyone with his fitness

[@Shomi_brat]

I always had the worst bonks when I was riding alone.If Mr. Connor was riding alone,I think that the dreaded bonk would catch him much sooner.Being alone,hungry and completely tapped out of energy is pretty devastating to the mind.Great video guys,again.

[@danielrose6418]

i totally agree, having company really does make for a more cheerful ride

[@bryanthomas3687]

Once bonked hard with 5mi and a good climb between me and home. Swerving and listing, I pulled into a driveway were a man was washing his car. I asked him for a Coke, or a candy bar or something. He went into his house and came out with a handful of random gumdrops and mints that it looked like he dug out of the couch cushions. They got me home 😄

[@85parrot]

we have a legendary story in my group of friends - one of them bonked so hard in a fairly isolated area that he ate the unchewed half of a discarded apple off a grass verge! bad times.

[@15idog]

Yeah man I've stolen half worm eaten apples off a tree but the side of the road just to get home 😂

[@bryanthomas3687]

I have kept an extra "bonk bar" in my saddle bag ever since.

[@jamesgoodwin7831]

☝️Thats awesome Bryan! 😂

[@ukaszzyka6279]

Not exactly bonking, but I was so thirsty once, while riding during a hot day on the trip to Sweden, that I had to take some water from the local cementary, kept there for watering the plants and cleaning the graves. I was literally stealing water from the dead Swedish ;)

[@mrpc2621]

Best quote: "He's like a bloody glucose camel"

[@Arthur-mh2uo]

Conor had really earned my respect by doing this as riding that far without food must have left him dead

[@jamesgoodwin7831]

Totally agree, Arthur. The man is all Heart! What a Legend. Truly inspiring

[@franklehmann426]

Well done Connor! Nice to see Hanks change of behavior from teasing when Connor was feeling well to supporting when he was really suffering.

[@Jayden-oi8km]

When you're so unfit you ended up bonking by watching this video

[@richardhaselwood9478]

I feel that :(

[@MarkMetEenC]

Just to be sure, I'm keeping my glycogen levels up with some pancakes while watching this video

[@Kimberly_Sparkles]

Friend, just lay back down and watch the video. You’ll recover better in a prone position.

[@sasham6486]

i feel that

[@davecasey4341]

I know I was winded watching this while laying on my bed.

[@Arfonfree]

As a diabetic (and antique to boot) I monitor my blood glucose on every ride. My response is far different from Conner's. One data point I missed, though, is what Conner's BG was after he bonked. I would emphasize what Hank said about not trying this at home. Depending on your physiology, an effort like that can drop you into very dangerous territory.

[@TheWickiman]

Yes, never do this as a diabetic. Also have your granola bars, gel and for really long rides Glucagen (emergency kit) with you and someone who knows how to use it. Just in case! Nowadays we are able to check our blood glucose on our phone, but years ago I was not able and depended on my feelings

[@Jinxie911]

@@TheWickiman eat 2 hours before the ride and check glucose levels. No emergency glucogen is needed in my case and I'm even a type 1. Check levels during long rides and add bars and gels accordingly. The intake of insulin reaches full effect in about 45 mins. I'm at times a bit jealous at others that don't need plan like we do before we go out on rides like this one :P The ride Hank and Connor do here would basically kill me without proper planning.

[@d716agq]

@Arfonfree @TheWickiman @Julie do you have any idea what hardware they are using to monitor their glucogen levels? Thanks, Will. (I'm guessing that hardware for non diabetics will be cheaper - and less accurate but sufficient for this purpose)

[@Arfonfree]

@@d716agq Not positive, but the outline of the sensor looked like the the Abbott Freelibre.NB: not measuring glycogen, which is the storage form for glucose. Measuring interstitial glucose, which does differ from blood glucose in complex ways.

[@TheWickiman]

@@Jinxie911I never have used glucogen yet, but for a 100km ride with over 1,200 m elevation I better have it with me. I lower my basel rate by 80% for the time riding and this normaly works perfect. Maybe after the ride a correction bolus is needed due to the stress for the muscles.

[@KaijuAlert]

Conor is an absolute machine, I think being ex pro, knowing what it is like to really go to the well and find nothing there in a way us keen amateurs could never envision, must give him a really strong mindset for these challenges. I know I couldn't stay as positive as Conor if I did the same ride without food.

[@4nz-nl]

I think I would have probably kicked the cameraman or something. I can keep riding but my mood really turns terrible if I bonk. Which is why I always carry a Snickers or two ;-)

[@sanpanuk]

So the tallest and thinnest GCN presenter goes without food on a 140k ride! Thought he would have bonked for sure. Should have called Freddie to go without food, as that would be more realistic and applicable to us the non pro cyclists. Anyway, amazing effort Conner. I bonked on my first 100me ride. I cycled about 60 miles and just made it to Marlborough.After scoffing two Cornish pasties, a slice of cake and a coffee, I managed to get back home. Now I always make sure I fuel correctly.

[@evanking920]

Back when I did long rides ( The Pleistocene) we carried bananas , packets of maltodextrin and Gatorade in our water bottles. One of my riding buddies bonked and resorted to eating a banana peel to get home.

[@malharfalke1715]

UCI might had caught him if he did that 😂😂😂

[@DinnerForkTongue]

The fiber may have fooled his stomach for a bit 😁

[@imjonathan6745]

thats like the equivalent of eating the weakest member of your group when lost in an island

[@danielbrown6152]

Hat’s off to Connor for not snapping at Hank. He had every right to become “Hank-gry” with all that needling. This was another excellent episode that delved into the science of sport performance. Bravo!

[@cornishcat11]

oh come on Hank-gry has to be the best comment on here well done

[@KristopherNoronha]

maybe he did, and they edited it out... but then again, Conor seems a thorough gentleman :D

[@bashbarnard]

I'm genuinely surprised they didn't try to kill off Hank again with this challenge 😂

[@imneveruploadinghere7180]

Can't make it too obvious, mate.

[@888johnmac]

lol , i was thinking the same

[@rileyvonbevern4652]

Turns out he rode 700km that week!

[@sullybiker6520]

"Can you cycle in an oxygen-free vacuum? We ask Hank to find out"

[@juliussepikas3395]

It’s just because Hank is doing 100km everyday riding, either way they just probably been asking Hank to do this challenge :D

[@felixsvensson5265]

I was on a trip in Spain and super naive. I assumed there would be restaurants on the way and I was hugely overestimating how long I was able to travel in a day. I had learned from TV how capable the body is and how long it can last without food. What I didnt understand is how incredibly shitty and weak it makes you feel.

[@ColinBroderickMaths]

@King Of Crunk Haha, I was really weirded out by you referring to her as "clean" until you mentioned the mud puddle.

[@cdofm]

This ride really shows how tough Conner is. I don't think I could have made it through half that ride without eating

[@TimpBizkit]

I usually get to around 40-50 miles without anything but water and maybe a bit of salt and then the power saps. I feel like Iron Man running on emergency back up power.

[@ColinBroderickMaths]

I've done one and only one century ride and was eating as much as I could physically take. Still limping and dead on the last ten miles.

[@RoelCuylaerts]

Being a diabetic I was really interested in the glucose numbers when he bonked. Since you used them throughout the entire film it is a really shame you didn't at that point. The numbers didn't show? I think he didn't really bonk at all. 🤪

[@3dflyer87]

I'm also a diabetic and thought the same thing!! Nobody bonks like a diabetic bonks

[@dianal.1279]

Yeah, I think they didn't show, because it was high.

[@DAS-KAMELEON]

I bonk smoetimes with 45mg 👽

[@grumpynerd]

I've done my blood sugar a few minutes after returning from a bonk ride and it was actually very high. Bonking is when your brain floods your body with cortisol to scavenge glucose precursors from anywhere it can, like muscle tissue. This is why habitual long aerobic exercise without eating leads to wasting in the muscles you don't use. Conor being a pro racer is necessarily a bit of a metabolic freak; he probably has much higher glycogen stores than a casual cyclist; his metabolic pathways feeding gluconeogenesis are likely more efficient too. This would make him extremely bonk-resistant; even a brief stop would allow his glucose levels to recover almost immediately. They may not have shown his glucose levels because they looked normal, which would send the wrong message to more casual cyclists. Since there is no medical definition of "bonk", you can't say he didn't do it, but I don't think he achieved a recreational cyclist's bonk -- he was still producing over 300 watts. This was more like tickling the dragon's tail. The last time I bonked I could barely propel the bike forward on level ground, although in part that's the metformin which makes bonk onset sudden and fierce. After that I bought a flip-top handlebar bag which I keep stocked with food.

[@TheDiablosix6six]

I say his sugar level wasn't as low as he thought due to his fat stores being turned into glucose. I'd say he was more tired from the 140km cycle and when ur body turns fat to sugar it burns a lot of calories doing so. Calories his body could ill afford to waste considering the challenge he did!!

[@darrenst441]

Bonking on the bike really is the most terrible feeling. All credit to Connor for his efforts, both physical and mental. 👏👏

[@fionahunt8530]

As a Type 1 diabetic, I 'bonk' on pretty much every ride - It's not just about eating the carbs but balancing that with the right amount of insulin which I have to do manually as my body no longer produces insulin. On the rare occasion when I get the levels somewhere near normal the riding is so much easier. But mostly it's a struggle as every day and every ride is different. There's no formula to follow unfortunately.

[@4nz-nl]

I've seen people with automatic insulin pumps around their waist, don't those also measure automatically? And is it possible to use one of those while riding?

[@fionahunt8530]

@@4nz-nl I wear an insulin pump but it only delivers insulin like most do. The higher tech ones can suspend insulin delivery in response to readings from a CGM (continuous glucose montior) which is also worn inserted in the stomach but nothing works as well as a properly functioning pancreas I'm afraid.

[@4nz-nl]

@@fionahunt8530 Thanks for all that info! Interesting, but yes, I'm happy I have a well functioning pancreas because it sounds like hell what you're going through..

[@lennartgretenkord6071]

You know of Team Novo Nordisk? A professional cycling team comprising only of riders who also have type 1 diabetes :) Best of luck to you and keep on riding!

[@fionahunt8530]

@@lennartgretenkord6071 thanks, I certainly will do.

[@elijahlimbaga661]

Connor: my power is a bit down, 440 watts 🤔 COMPETITIVE Hank: 😑😑😑

[@impaledface7694]

I see conor got the second wind. Have had that plenty of times... but we all know what happens after. Done a fair amount of fasted riding and it's a struggle. Stopping at a cafe and having a cookie or anything with carbs is a crazy experience.

[@benedictearlson9044]

Yeah you don't want to tighten your sails into a second wind it's all illusion! Use it sparingly and do 50% of what you feel you can do.

[@davegee124]

i did a an 75ish mile ride on road on my mountain bike about 20 years ago when i didnt know any better about eating,the last 5 miles home i was crawling and the last mile i gave up i couldnt even stand up when i got off the bike,i hadnt taken any food and only 1 bottle of water..lesson learned.

[@FlatSpinMan]

That would do it all right.

[@dalailambda9420]

Same.... I did a 93 miler on my old 26er mountain bike, no food, 1.5 litres of water, 1500m of climbing, on a hot day.... To this day I cannot believe I made it, I've never felt that bad before or since...

[@ap5194]

Sounds disgusting that does

[@jack002tuber]

Been there done that

[@roopehaimila4353]

Did the same experiment. Planned a short ride but it felt so great that I kept riding.. That was a lesson learned 😅

[@herculesrockefeller8969]

I've bonked a few times, it's not pleasant, and can be dangerous, especially if you are dealing with traffic. Almost everything is affected, your vision, power, and judgement, which can be a terrible combination in the wrong circumstance! Now I take measures so it won't happen again.

[@eliteharrington7377]

12:29 Mother Earth thanks you for tucking the wrapper into your pocket, instead of tossing it at the side of the road 🌍

[@holdencaulfied7492]

Thanks hippie

[@grahamballard7041]

What I usually do is roll up the gel or bar wrapper and slip it under the edge of my shorts, that way you don’t accidentally pull out an empty wrapper and drop it in the road without realizing it!

[@DinnerForkTongue]

@@holdencaulfied7492 Get bent.

[@vyr1316]

@@holdencaulfied7492 Get bent.

[@mathieu9442]

@@holdencaulfied7492 Get bent.

[@colinfrei7136]

I know the feeling of Bonken. My first ride after a big injury and my longest and highest ride ever. Over 1000 metres of climbing and about 30 kilometres. we actually only wanted to ride 5 kilometres and therefore didn't have anything to drink or eat. This ride also had a lot of Hike a Bike in it. At the end, we arrived at over 2000 metres above sea level and got cheese and meat at an alpine pasture. Since there were almost no fountains on the ride, we almost felt like we were dying of thirst. In the end, we swore we'd never do that again. But at the end of 2020 we asked ourselves what the best experience was and we both said it was this trip. That's why we're already planning it again, but this time with food and water. Colin, 14 years old, Switzerland, Grisons

[@jenniferw6081]

I was forced to search the freezer for leftover hot cross buns to eat while watching Connor suffer. Amazing.

[@mikebutcher1984]

As a type 1 diabetic, I've miscalculated my carb to insulin ratio on rides a few times, never nice having to stop a ride to eat fast acting carbs to get your levels back up, but on the other hand, never nice to check and realise your levels are 3 times higher than they should be. My glucose graph sometimes looks like a stage profile of a TDF mountain stage, even after years of cycling, I still struggle to get the correct balance sometimes. Would be interesting to see GCN do a video with the Novo Nordisk team about how they monitor and manage their levels during races

[@liammarcelventer1880]

You should seriously consider/ research the Keto diet unless you are a Cat 1 racing athlete.

[@mikebutcher1984]

@@liammarcelventer1880 Diabetes affects everyone in different ways and I know keto works for some but unfortunately not for me. I tried keto a couple of years ago, but when going out for a ride for more than 45 minutes I'd go into hypo. I still eat some keto meals when not riding/exercising but unfortunately keto and exercise aren't a good mix for me

[@fionahunt8530]

A video with Novo Nordisk would be super interesting. I'm Type 1 too and my BG profile is also like a TDF mountain stage. So difficult. Non T1s just do not understand it.

[@kleberguedes]

Being type 1 diabetic, I "bonk" every time I don't have the right amount of insulin or fuel. I recognise Connor's face, feeling and lack of power. These sensors are key to keep me going, you look your watts, I look my sugar levels.

[@bratSebastian]

Glucose level rises not only due to released glycogen stores in the liver, but from fat cells filled with triglicerides broken down to - aside fatty acids - glycerol transformed back to glucose. That's why Connor was feeling full of energy after a restart, because while resting, he was getting back a lot this way. That is a thing to remember not to panic, but to have a not too long rest (like 15mins or so) and then continue a ride although it shouldn't be more than active recovery pace. The longer a ride continues that way, the better a ratio of time spent on saddle to off while resting, till you're able to continue without any stop. If you're experienced, it's gonna come around 100km after the bonk.

[@sparx151]

My worst bonk was when I was about 90k deep into a 120k spin. Got dropped my the group, stopped at a petrol station got a 3 for 2 deal on yorkie bars. Ate them all but I was so deep in glycogen debt it didn't help so I called for a lift. The brain fog set in as a i descended into the nearest village for collection... Then rode into a gate trying to find the car 😅

[@MentalHealthJourney]

As a recovering anorexic (who genuinely loves sport and cycling but has a huge issue with over exercise), this was actually and incredibly helpful video. I kid myself I think that because I got round, did the ride or whatever exercise it is, that I’m fine I don’t need fuel. But actually seeing the comparison- yes you both got there but in significantly different states and having had significantly different experiences - put it into perspective how things could be if I can manage my intake better. Definitely food for thought. I’m really fortunate to be finally working with a person centred eating disorder team who understand that total abstinence from exercise isn’t the way forward for me (we tried and it just came back even more intense), and are working with me to set goals that includes thinking about proper exercise nutrition. Thanks for this

[@davidheathfield5040]

I don’t know what’s worse, riding all that way with no food or riding all that way with a hyperactive Hank

[@sullysullster8217]

Great segment. I tried the opposite a few years ago. I tried 60 miles with no endurance/ base mileage. I took all the powerbars and ate and drank as much as I wanted. The results were similar. No matter how much nutirition I took on, my body wasnt used to the mileage and had the same bonk feeling. A horchata from a mexican restaurant on the way back was a good choice to help me with hydration and carbs on the home stretch. On another note the production of this video was cool especially the dark dub music at around 17:00 with the crow echoing wasnt lost on me. Nice touch.

[@matthewallen1709]

As a yardstick this needs to be tried a second time with Connor fuelled and James on water to find out if physiology plays a part. Connor mentioned his professional experience may have helped him so get Freddie out as a comparison as well.

[@FlatSpinMan]

I can just imagine Freddie’s response to reading this.

[@thegrimpeur]

Yes, the only reasonable way to get the answers we need is to try and bonk every GCN presenter and compare!

[@medleyshift1325]

I'm pretty armature and I bonk after about 80k with medium climbing. Still road another 30km home after the big climb that broke me though. Tbf no where near Connor's watts I'm sure, but you'd probably surprise yourself with how far you can go.

[@HughCStevenson1]

No breakfast, that will kill anyone!

[@mattshipstone9361]

The temptation to kill and eat Hank must have been near overwhelming!

[@DinnerForkTongue]

Hank is all bone and gristle, not good for food at all!

[@james-tennis]

The camera men and gcn film cars probably would deter you from turning to murder and canabalism in 6 hours 😆

[@andyhaochizhang]

@@james-tennis yes, eating people on camera is not allowed

[@seahorserider33]

Hahahaha 🤣

[@ValentinSerbanut]

I would have loved to see the full blood glucose graph relative to the distance progress. Also you should have tested Conor for ketones after the race. It would have been very interesting to see if he actually burned protein (his own muscular tissue) once his glycogen ran out.

[@ttb1513]

I looked up ketones. I read that when your body burns fat, ketones are produced in your blood and urine. Burning protein and breaking down muscle tissue is certainly interesting. How does burning protein affect ketone levels? I didn’t stumble across anything concerning protein, just fat, as it relates to ketone levels. Thanks. Agree that complete graphs over the 140km would be interesting.

[@masoncox6036]

​@@ttb1513ketones are evidence of muscle proteins being broken down. You wouldn't find them in your urine without breaking down muscle

[@gilgermesch]

Connor: "We've been dropped out here..." Ollie: *profuse sweating*

[@jasonmcgrody9472]

With more long-distance riding in late 2020 and 2021 I was able to do 100km and only ate 400 calories. 235 Watts average and total time was 3:22. Certainly a lot easier when you've trained for longer distances. 140km? Nope. That extra 70-80 min riding would be more than I'd like.

[@inbearbeitung7481]

I'd love to see a video behind the scenes, seeing the motorcycle, preperation for the videos and so on

[@thebigg2345]

It'll probably be on GCN+...

[@benedictearlson9044]

15:45 This musical interlude perfectly encapsulates the other-worldlyness of a really bad bonk - it's frightening! You can be suddenly thrown into a very odd topsy turvy sense of reality where you're completely powerless and your mind goes to a very dark place. Sitting alone propped up by a fence barely able to lift an arm with sheep laughing at you is not a fun place to be, you feel like you could be blown away into the clouds and simply effervesce away. :)

[@joshgriffiths8201]

Should do this again, but with Manon fuelling correctly taking Hank on a tour of her favourite cafes but he can only drink water!

[@testme2131]

...then let's see if she fist-bumps him at the end

[@ScrapKing73]

I find I can ride for 5-6 hours on an empty stomach without bonking, so long as I stay in zone 2 most of the time. These days I always ride on an empty stomach, and over time I’ve done longer and longer rides that way. Your body can adapt to almost anything, if you build up to it slowly.

[@benedictearlson9044]

Being aware of how hard food was to come by not even that long ago this is surely how most human's metabolism functioned before the modern age. If you couldn't walk or jog about in search of food for a day or two without collapsing into a heap you'd not survive.

[@ScrapKing73]

@@benedictearlson9044 Good point. Makes sense to me!

[@richycoles]

Nice to see some of the roads I ride in South Wales on a GCN video. Made them look good too!

[@reactivatedforever]

Great episode! Greatly enjoyed Connors honesty and the blood glucose readings. Would be interesting to hear a follow up to how well Connor recovered and if his power was still affected. Would be also interesting to have hormones assessed too to help discourage athletes from disordered fuelling.

[@DaveIsTheBestMan]

Its all about the pace you go at. I've done 250km without any food. You will eventually get down to zone 1 and ride really slow. But you can still ride, just feel your body and go at the pace it wants to go at.

[@karlmathew1342]

In my case I find coffee helps.

[@DinnerForkTongue]

Pretty much, yea. Don't try to force a rhythm if you got a glycogen deficiency, let your body dictate the pace. After all, bonking is being unable to go any harder.

[@donsolomon8501]

Its pretty epic how the clarity of his conversation changed after his 1st effort. Hank was still Hank.

[@armella_ultramyggen]

At my very first ultracycling race. It was 400 km unsupported and I drove almost all the way, but when I had like 10 tp 15 km left, my tanks was empty. I couldn`t sit on the bike or pedal, I was totally done, so lay down in the ditch and called for help. I learned the hard way, how important food is and the right food.

[@josephryan5949]

Many years ago when I was a young lad, I borrowed my mum's bike and took off on a long spin around the country roads, up hills and down dales. I hadn't the sense to take either food or water back then. I still remember the struggle back up the hill to my home, completely wiped out and ashen faced. My dear mother had a lovely meal prepared, but I couldn't even look at it. I went straight to bed, absolutely exhausted. I must have been completely dehydrated. It was certainly an education !

[@angelag5708]

The height difference makes it look like we are shooting Lord of The Rings

[@tibiolah]

26:24 "not looking down on anyone"... Well he was sitting down, otherwise he has no choice but to look down to everyone

[@epicme2000]

Bonked once riding a 20km mostly flat stretch for the 1st time few weeks after learning to ride a bike @ age 40, beliving I can ride and go anywhere like those dudes I see riding fast and looking cool. No food or water with me. Well, I had it very bad. Even pushing the bike half way home was like an uphill task. Lesson learnt. I never head out with more than enough fuel to last twice the distance I am going even on short rides.

[@adammccabe8779]

All the GCN presenters need to be put on lifetime contracts....like even if they don't want to...they can never leave us. Keep up the great content

[@GreatJoey91]

"I've got nobody else to blame but myself, because this way my idea." Conor 'the glucose camel' Dunne, you absolute legend. I can't believe you made it so far without food 😳

[@JaySmith-nn1bg]

I never comment on KZbin, but I must say something here... WELL DONE MATE!!!! So VERY Well Done!!! It's when we are challenged with our own perceived limits, that we find we rocket past them in ways we never thought possible. Cheers.

[@CedarScott]

I have watched this video a couple of times. I am curious how Connor's recovery day(s) felt. Especially at my age, if I go deep into my reserves, it really takes time to come back to anywhere close to performance pace.

[@duaner3817]

Yeh me too. VERY intrigued to see what recovery looked like. Hours /days...?

[@neildaniel8232]

Fair play Conor, you absolutely murdered the pronunciation of Llangynidr!! I'll let you off though as getting that far on no food is an epic effort, hope you enjoyed the next few meals.

[@sumljivc]

When I saw the title and Hank in the thumbnail, I was 100% certain he was going to be the one suffering. Well, well how the turntables ...

[@drakes3082]

was cracking up everytime when you guys stopped Hank smashing down the bars getting Hyper and laugh while Connor suffered. Hunk just couldn’t stop smirking lol much respect to Connor what an absolute glycogen tank !

[@albertharyanto2544]

Me bonk experience made a taxi driver scared. Imagine you’re resting in your cab at 3am and suddenly someone pounding at you losing out of breath asking for help

[@rickgoodwin6765]

First off. That looked like an amazing ride. Some very beautiful area there. Conner did amazing. I never thought that he would have made that whole ride. Shows what I know. This has been some very good investigative journalism. A great experiment. I feel for him because it probably took him several hours to recover. Thank you both. Great job.

[@tjlazr]

I’m pretty new to cycling and built up to a 60 k ride which, naturally, I took no more fuel than a water bottle for. To be honest performance was pretty consistent until last 10k and I felt terrible the rest of the day. I am certainly going to fuel better next time but full credit to Conor, no idea how he did that!!

[@岩男沢山]

That "feel bad the rest of the day" problem is what drives me really nuts. Recovery after a hard bonk sucks bad enough that it is good motivation to be careful.

[@michaelberger6699]

Drinking a lot will help you feel better sooner. You liver is doing a lot to clean up metabolic trash!

[@SFSomega]

Conor is an absolute beast! I have bonked really hard, but not during cycling but during hiking actually. I was literally walking in slow motion until I reached a shop where I ate 2 Snickers and drank 2 Colas. Then I felt life coming into my body instantly and I was able to walk the last 200m to the car.

[@kathrynhills7174]

Mine was a long (19mile) run. Was fuelling, but not enough. Fortunately almost home, but staggered the last few hundred meters, almost fell over. No chance of extra loop to get to 20m as planned. Lesson very much learnt.

[@andrifsig]

This turned dark there for a moment: Hank "you are on deaths door there my friend" proceeds to laugh maniacally! I do a bit of cycle touring. On my first tour, the second day of the tour, I had to cycle over two mountain passes, On an overloaded bike. The last 5km of the ride took me over an hour. I got to a restaurant next to my campsite. Ordered the sloppiest meal on the menu. Took me abut 90 minutes to set up my small camp. Did stick with cycling and cycle touring though. Started weighing in at 162kg, now down to 109kg so pretty happy with my choices.

[@ygtcbee23]

Hank experienced a clip in Mechanical. Like Matt Stevens

[@andrifsig]

@@ygtcbee23 well that doesn't really suit my narrative! ;)

[@ygtcbee23]

@@andrifsig watch the clip and listen to him trying to clip in and miss. It's hilarious. Instant Karma

[@85parrot]

having a proper bonk and then eating some sugar is amazing - physiology in action. i went from lying in a ditch in mallorca telling my mates to leave me there, I'd hitch back, to joining in with a chaingang back into puerto pollensa. It's like you can feel yourself come alive again within a matter of minutes. powerful stuff.

[@richardbecton6879]

Hank’s laugh @ 10:45, I thought Matt was making a return for a second.

[@kevinmcbride6961]

As a type 2 diabetic, I actually am a bit of a glucose camel as my blood sugar is high most of the time. Things like gels and carb loaded bars are like cryptonite to me and will cause a bonk. For me a ride starts with a strong coffe and a bannana, topped up throughout the ride with electrolytes and some solid food to prevent cramps. Connor looked knackered at the end of that ride but, if you've had a bonk or witnessed one, I'd argue that he didn't actually bonk. That just shows what an athlete he is. Massive effort.

[@headlyredbear9128]

I once carried on for ten miles after bonking hard, threw the towel in just outside Keynsham as i was going a bit blind and unable to ride in a straight line, if i had'nt had a phone on me i'd have probably spent the night there. Never again.

[@tahirsaid6993]

Amazing effort. I have done this accidentally when we went out for a 120km ride but in scorching heat and everywhere we stopped hoping to eat something was closed. Never bonked so hard. I could smell ammonia for hours after!

[@UbzUnclemax]

I once bonked so badly that I was frightened to pass out. My heart rate couldn't exceed 90 BPM anymore and my speed dropped to 10 km/h (all on flat, windless conditions)

[@supernoodles908]

Dam that's a hard core bonk. Lesson learned

[@gcn]

That's a proper bonk!

[@taqiya.b5228]

Same here. New to road cycling but went on an 80k with two cereal bars and a banana thinking it was enough. Luckily it was just before the descent home

[@OFFSHOREDOUG]

Been there, o2 was at 89%. Slept then carried in.🙈

[@easony_snaps]

just realise that i need to refuel this often, once went to a 160km ride with a few power gel and nothing else. I guess it ended surprisingly well tho after seeing this video.

[@leeblanchard6434]

Great video guys👍, I've just starting cycling and experienced this in my first two rides, both within 25k. Very difficult when my fitness levels are so low. I will push through and really appreciate all your help via your videos. Thank You

[@007-Bond]

A bar every 15-20 mins!?! Might as well bring my entire fucking fridge then eh?

[@peterindaco96]

Makes cycling as expensive as needing petrol.

[@james-tennis]

I wonder if they just mean biting a bar during that time period. Not necessarily eating the entire bar because you'd actually gain weight on your 160km ride lol

[@navbravic1355]

@@james-tennis I mean he said he wanted 60-90g of carbs per hour. I'm looking at a granola bar right now and it's 18g of carbs. So you'd need 3.3 - 5 bars per hour, which is 1 full bar every 12-18 minutes.

[@GodzillaGoesGaga]

​@@navbravic1355 A granola bar is about 150 calories. For an hour of exertion say, as a fit person, you burn ~750 calories/hr, that means you need about 6 bars per hour (ie one every 10 minutes). So the calculation seems correct.

[@GodzillaGoesGaga]

This assumes you aren't eating anything else (like a big breakfast or lunch etc). This will keep you on the level for glycogen stores.

[@aksting]

I bonked about 120km into a 135km ride. I was going uphill at the time and attempted to get out of the saddle, but my legs said NO. My arms could barely hold on and I found it difficult to focus. When I finally finished it took all the effort I could muster to unclip the first pedal without falling.

[@markush7001]

My worst bonk left me 2 miles from home pondering whether or not to call a ride.

[@rebinu]

Worst feeling

[@GeoffreyEstall]

Just got back in to cycling but really serious now as undertaking the London Ride 100 next year, 2024. Never undertaken 100 miles before so this film was brilliant. Very informative.

[@supernoodles908]

A glucose and power plotted on a graph would be great to see the relation between power to glucose in the blood

[@supernoodles908]

@@CarpeDiem13x Indeed. It would be interesting to see a large data set

[@ironorrii]

Conor, Way to go. Pure determination and commitment to the challenge.

[@malharfalke1715]

12:35, poor Connor being persuaded by hank enjoying his treats

[@itsdouetthierry]

This is a good video. I have type 1 diabetes and therefore insuline dependent. I MUST inject insulin to manage my blood sugar. Problem is, we NEVER know exactly how much to inject based on food intake, mood, health level, exercise and about 1000 more other variables. So sometimes, I (we T1s) over treat with insulin. And when you run out of glycogen, the tanks are empty because the insulin has "opened up the T cells to consume the carbs". Carbs are not only essential for the indurance, but also to keep the brain functioning. Us T1s, we hit the BONK mode when we have too much insulin on board and not enough glucose and/or glycogen reserves.

[@tomlawless4406]

That was the bonk of the year hah, seriously well done for getting to the end.

[@dashcoxon4727]

Excellent vid cheers. WHen I first started cycling I was tricked by my apprentice into doing 103 miles over the pennies. We had a bag of crisps and a Mars bar. My longest ride before this was 30 miles. Needless to say we both bonked and didn’t get back home till after 11pm. The plan before we set off in the morning was to go for a pint when we got back 😂. We still had 50 miles to go when we honked and ended up walking the last 3 flat miles.

[@jonathanstow4820]

Stupendous effort from the big man.

[@runfrankfurt]

You can minimize the effect that a Glycogen depleted state like a bonk has on you if you train your body to become fat adapted and more efficient using fat as fuel. Of course you would still have to reduce the intensity due to missing Glycogen after running out, but you could still ride a decent clip if you are fat adapted and would not feel as horrible. I can still operate fairly well just using fat as a primary fuel source, especially on longer endurance activities which are in an aerobic state of intensity. Not being too dependant on carbohydrates is something you can train your body, but it takes time.

[@fredrikzander4877]

The legend says that later that day, Conor changed his name to sir eatsalot.

[@carlgarcia8091]

So much respect for this guy. Thank you for teaching us something important today. 140km without fuelling! Damn...

[@malharfalke1715]

I never super bonked, but had a serious one with my friends on a 95km ride when we had just a couple of energy gels and a milkshake in the morning just as hank had porridge

[@Rainaman-]

95k seems short. Was it with lots of climbs?

[@ericlange1524]

I am a frequent smoker and to me the 100km mark is the magic mark haha

[@malharfalke1715]

@@Rainaman- not a lot, but few 3-5 percent gradient, also, I only ate 2 gels during the whole ride, and it was during October heat in india, temperatures are pretty high and it was worse Also, I was like 14 at that tim

[@DJBigMD]

" i can hear it on his language" 80 km later boy i can hear it too, can't understand what Connor is saying anymore . Respect to this man.

[@LifeInJambles]

Yeah once he started falling off, it was a jumble followed by three words apparently chosen at random.

[@rugbier666]

I actually really want to see the reversed as well. Conor stuffing his face and Hank anything but his hyper self😂

[@reactivatedforever]

Exactly!!!! Data comparative and summary would be great.

[@iancraig2507]

So much appreciate what you guys and gals do for science. I am 67 and try for a 3 to 4 hr ride a few times a week and I am learning so much from you.

[@Alniemi]

I was 77 miles from home and could not find a good camp spot. I HAD TO CALL MY MOM D: it was a learning experience XD

[@mechy2k2000]

@@MJAP123 I always carry my wallet or at least some cash to buy some food from a gas station, but not always an option

[@jamesbull9879]

Amazing video. Your last comment about years of experience are so true. I hit the wall so much quicker, probably after 3 hours and then I’m done, power goes, focus goes and ability goes. Top effort!!

[@Gcman0274]

That's a small fortune of gels/bars Hank was stuffing in his pockets. Would be interesting for Connor to do this against someone who has the metabolic flexibility who regularly depends on fat as fuel and doesn't purely rely on carbs.

[@ForwardLooking832]

Yes. I like to see this repeated with someone who is very well fat adapted / keto type of rider who can switch between ketone and carbs as required. I wonder if there are any professional riders who have that flexibility. Seems to me I think they are all mostly carb-based.

[@jasonmcgrody9472]

@@ForwardLooking832 It's unlikely their power numbers, especially the 5-minute efforts, would have been that high in the first place. No pro rider does this because it's not a way to actually win anything.

[@desertrainfrog1691]

@@ForwardLooking832 There isn't. Keto is only done for weight loss, not performance. You're not winning anything riding around in ketosis.

[@andyhaochizhang]

@@ForwardLooking832 probably not. It’s like one GTN video pointed out, being more fat adapted potentially limits efficiency with carbs, which is critical at high intensity. So competitive endurance athletes can probably not afford to be too fat adapted.

[@HkFinn83]

@@desertrainfrog1691 yeh maybe not full Keto, but a lot of endurance athletes ‘train low, race high’ with sugar. They would have a much better ability to manage I’d imagine.

[@larisonjohnson]

Conor, that is amazing! I can usually manage about 50k without food. Discovered once accidentally and then repeated the accident the following year. I don’t think there is a worse feeling than the bonk at 10k to go, knowing you just have to limp home. My cliff seems a bit steeper than yours. Feeling every square...I’m suffering just watching you.😅 would love to hear what your whoop said in the days after. Chapeau mate! Well done.

[@0connell07]

Conor is big enough to store energy for weeks 🤣

[@MJarthur95]

The man’s a giant tanker compared to hank

[@cahal]

Bloody hell Conor...I bonked for the first time today at half your distance. Spilled my last gel all over my bike because I ripped it badly. Mad respect you absolute machine.