What does ‘bonking’ mean when cycling?

What does ‘bonking’ mean when cycling?

On this edition of the Ask Coach Parry Cycling podcast we chat to our cycling coach Devlin Eyden about the meaning of 'bonking' on our training cycle rides or during a race. He gives us an indepth explanation and tells what the best method is to overcome this.

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David Katz:          Welcome back to the next edition of the Ask Coach Parry Cycling podcast. I’m Mr Active, David Katz, with me once again is Devlin Eyden and another great question we’ve got coming up for you. We’ve been prepped and asked on this one and I’ve seen this happen first-hand with a friend of mine, I eat too much for it to happen to me. It really is serious when it does happen and it revolves around bonking. Devlin, basically what does ‘bonking’ mean and what can you do if you find yourself in that situation?

What exactly is 'bonking'?

Devlin Eyden:      Bonking clinically known as what we would call hypoglycaemia. What it is, is your glycogen stores get depleted after about 90 minutes of intense training, of consistent, intense training. What happens here and what leads to the bonking is not enough fuel in the system. If you have not been eating, if you haven’t had a full tank, glycogen source going into the event, or you haven’t been eating during the event, taking in your carbohydrate drinks throughout the event, it happens then that the glycogen stores deplete and you hit what we call bonk or as some might refer to it as well, as hitting a wall, where you just absolutely run out of any energy that you have in your body.

Symptoms, so that you have some sort of idea of what it might feel like, would be you feel extremely weak, tired, you might get light headed, potentially nausea every now and again and as I mentioned, it’s purely a case of your body has just run out of fuel and you’re not going to be able to sustain the intensity for very much longer.

Make sure you are well fuelled for your cycle training

If you catch it early enough, so you can feel that bonking coming on, my advice would be to take some form of simple carbohydrates, something along the lines of an energy gel, wine gums, jelly babies, that sort of thing. Possibly even a sugar lump, not that we easily carry sugar lumps around, but the idea there, just to get something into the body that’s going to digest quite quickly and get into the system so that you get that immediate energy release.

Something along the lines of an energy bar for instance, does take a lot longer for it to process into glucose for that energy source. My suggestion would be to try and take a gel rather and get something in that can process a lot quicker and you can digest it a lot quicker.

On the flip side of that though, if you try to push through and you haven’t been 100% sure exactly what’s happening and you catch it a little bit too late, it is a lot harder for you to then play catch up. My advice there would be to try and get, again, get something into your system as quickly as possible and actually stop and just give yourself a little bit of time to recover. Keep fuelling, keep drinking, but make sure that you actually stop training or stop your race for a little while, just to try and recover a little bit.

Key is just to stay fuelled though. Always making sure that you are eating and if you do catch it early enough and you’ve managed to get some food in, make sure you’re eating every half an hour still for the rest of that event or the rest of that training session to at least get you back.

The problem with this though is you then tend to find that recovery afterwards takes a little bit of a knock as well. You will feel flat in your next training session, if it’s a training week for instance and you bonk on a long training ride. Making sure that you’re always fuelled and then refuelling as quick as possible and taking a little bit of time off.

Be vigilant with your nutrition on the bike to stay out of danger

Keeping in mind, when you do hit the wall or you do bonk, it also has an effect on your mental, your cognitive ability, so it does become slightly unsafe. I’ve seen it first-hand as well, in technical, single track on the mountain bike for instance, when we’re at high speeds and bunches on the road, the issue then comes in where your decision making ability takes a little bit of a knock and then just becomes dangerous for you and everyone else around you as well.

That’s why I do suggest to rather stop, try and gain a little bit of energy, get some stuff in and hopefully try and progress a little bit from there. It is important though and we have touched on it several times in previous podcasts, but you need to stay fuelled and you need to practice what your nutrition plan is going to be for race day and in your training.

You need to know what’s going to work for you, what doesn’t work for you and how to go about your strategy in terms of when to eat and how much you eat, whether it’s a carbohydrate drink or actual foods/solids that you’re taking in. Remember, when you bonk, and you bonk hard, it is really difficult for you to play catch-up and recover from that quickly.

DK:         You definitely want to heed the coaches advice on this one and talking about the coach, if you want some one on one time with Devlin and to join a really engaged group, all you need to do is sign up to the online community. Go to coachparry.com/join for exclusive members-only video content, video coaching and access to the private Facebook group.

From Devlin Eyden and myself, Mr Active, David Katz, we’ll catch up with you again next time.

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