Bonking!

Now, here’s one of life’s little paradoxes. The subject of ‘bonking’ clearly has more than one meaning and the two that immediately spring to mind as a cyclist, coach and red-blooded male are unquestionably at opposing ends of the pleasure spectrum. The first and more obvious connotation I’m sure needs no introduction and is a rather pleasant and happy thing, but the second (which has huge relevance to you as a cyclist) refers to the abrupt physiological response to ‘running out of fuel’ when you’re on a bike ride – or more specifically ‘running out of carbohydrate’. This is often referred to as ‘hitting the wall’ in marathon running, although in cycling we call it ‘Bonking’ for some reason? Cycling’s more efficient than running and ‘Bonking’ is easier to say than ‘Hitting the wall’, so I guess that’s progress? On a physical and emotional level, it doesn’t get much worse than this and these feelings are enhanced significantly I reckon if it happens like a shot out of the blue on an epic bike ride from London to Skegness (about 130 miles), within a stone’s throw of your 16th birthday, slap-bang in the middle of the UK’s Cambridgeshire fens, 20 miles from civilisation. Yes, that’s when I first bonked and I cried for my mummy…

To expand upon this a little further, what exactly does bonking feel like?  Well, it made me cry and I reckon I’m pretty hard, so it must be quite bad.  Basically, you don’t just slow down a bit, you completely run out of energy, everything starts to flash and you get reeeeeaallly hungry.  Everything stops – and I mean everything!  It’s like a ‘Matrix moment’ gone wrong.  Stuff slows down in your little internal world, but unlike said epic blockbuster, the rest of life goes on at the same speed.  It’s like a really bad dream full of slow desperate decisions. It’s an awful feeling – much worse than I’ve made it sound...


metabolisim-small

The ‘Metabolism Simplified’ diagram above demonstrates quite clearly why the bonking process happens. If one were to draw a horizontal line right across the diagram immediately under the word ‘Pyruvate’, this separates anaerobic from aerobic metabolism and we get all of our energy for bike riding from both of these processes. Aerobic basically means ‘with oxygen’ and anaerobic means ‘without oxygen’. What’s significant here is that we can’t get any energy whatsoever if carbohydrate is missing from the top of the process. If you remove carbohydrate, you won’t get Pyruvate and if you don’t have this, you can’t metabolise and make any energy FULL STOP. The diagram also clearly illustrates that although one might have plenty of fat and oxygen available as fuels, you can’t burn these and get the energy out of them without carbohydrate being present. When your carbohydrate stores get really low, your body can derive carbohydrate from protein through a process called ‘gluconeogenesis’ and then drip feed this into your metabolism. This is slow, clumsy and involves breaking down your muscle tissue though, so it’s quite unpleasant and pretty counterintuitive if one of your reasons for riding a bike is to get fitter and stronger!

Suffice to say then that carbohydrate is a pretty important nutrient to us cyclists and one of the problems is that we can only store so much of it – we have a finite supply. So surely the biggest protection against what is quite frankly an embarrassing and undignified occurrence is to take a pragmatic approach to one’s carbohydrate intake. Here’s a 3-pronged attack, guaranteed to dramatically reduce the chances of this happening to you:

1)     Carbo Load: This is reasonably simple if you’ve got a healthy appetite like me, because it just involves eating loads and the whole idea is that you’re super-loading your muscles with carbohydrate prior to a big ride, event or competition so that you’ve got more fuel in the tank to start off with.. There are various empirically tested protocols for carbohydrate loading, in fact one can go right back to the 60’s to find information on the first ones. Some methods involved depleting your carbohydrate stores by training really hard in the lead up to an event and starving yourself of any food with carbs in it. By the end of this depletion phase, you would look all sunken eyed and, well, ill quite frankly. Then, to shock your body into carb storage, you’d stop training and eat loads of high carbohydrate foods for the few days leading up to the event.  This was indeed proven as an effective method for loading, but it’s not as good or as easy as a strategy devised during research at the University of Western Australia in 2002.

With this later protocol, what you have to do is conduct a little warm up to get your body temperature up and then do a flat out 3-minute sprint as hard as you can just 24 hours before the event followed by flat out high carb eating. This 3-minute bout was found to simulate glycogen synthesis on a massive scale and muscle biopsy’s showed a significantly greater loading effect than any previously documented methods.  It’s simple, because it doesn’t involve any unpleasant depletion stage and who couldn’t find the time to do 3 minutes of cycling the day before a big competition?

So for the sake of simplicity, essentially what you need to do is step up your intake of carbohydrate-rich foods the day before ‘D-Day’. The ‘D’ in this instance stands for a variety of phenomenon that you’re likely to experience if you don’t get this right. These include deprivation, debilitation, desperation, depression, danger, dignity (lack of), daftness (the appearance of) and ‘do I wish I’d paid more attention to that article on bonking?’ Not necessarily in that order either - and some of these feelings you’ll experience more than once!

Anyway, so you’re going to consume more calories than normal and an extremely high percentage of these are going to be from carbohydrate. This means choosing foods that have a high carbohydrate:fat ratio.  For the sake of one day, you can pretty much ignore protein, because you’ll get enough of this by default. So, as well as eating foods like pasta, rice, potatoes, noodles, cous cous, bread and beans (and bananas while we’re on the ‘b’s), you’ll need to look for sugary things that don’t contain fat. Chocolate digestives for instance contain 24grams of fat per 100gram compared with just 6grams per 100 for fig rolls. A small amount of the remaining ingredients are protein, but essentially the rest is carbohydrate. It stands to reason therefore that if you eat the equivalent weight in biscuits, you’re going to get a whole lot more carbohydrate by eating fig rolls over chocolate digestives. As a general suggestion, you should look at the nutritional info on food packets when you go shopping and opt for high carb and low fat. Flavoured rice cakes are great and for the purposes of carbo loading, dare I say it, so are many kinds of sweets/candy like wine gums/boiled sweets – also popcorn and many more snacks that could be considered unhealthy and the sort of thing that you give to your children if you want them to be badly behaved and a menace to society. Just remember that you’re avoiding the fat.

Finally (and it’s pretty important too), you MUST consume 3grams of water for every gram of carbohydrate you consume, or you won’t store it. Many foods like pasta and rice contain this much water anyway, but the drier snacks and sweets don’t. You won’t drown if you drink too much, so my advice is to drink water purposefully, verging on the obsessive, but leave some for the wildlife and polar ice caps or collectively we’ll create an ecological disaster we’re all likely to feel quite guilty about!

Sugary drinks will supply carbohydrate and fluid, so these should be on your radar too.  Avoid diet drinks, because these have no calories and contain nasty chemicals that fool your brain into thinking you’re having carbohydrate. The diet drink is ‘the biker’s saboteur’ in my book.

2)    Carbohydrate During Exercise:  If you’ve followed the advice above, on D-Day morning, you’ll be loaded with carbohydrate and feeling good. It stands to reason that if you consume carbohydrate while you’re exercising and are able to use it, you’ll deplete your stored carbohydrate more slowly. Research has proven beyond any doubt that this is definitely the case and that your body will be able to process and use approximately 1gram of carbohydrate per Kg of bodyweight per hour, so if you’re 70Kg, you’ll be able to use 70grams of carbohydrate per hour. It’s not my job to bore you with research, so I won’t, but studies in the last couple of years (and some new ones out in the last couple of months) have since demonstrated that if two different carbohydrates (Maltodextrin and Fructose) are mixed together in a 2:1 ratio, you can burn 30-40% more carbohydrate per hour, which is quite staggering. For more information on this, why not take us up on the same offer we extended to you in the last issue of Mountain Biking Australia. We have a 52-page Performance Resource available, with a recommended retail price of $12.50, which we’ll send in an environmentally friendly electronic format FREE OF CHARGE if you e-mailThis email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. . Just pop ‘Free Performance Resource’ in the subject heading and we’ll e-mail you the resource back by return. Isn’t that splendid of us?

 

So, for the sake of argument and to keep it simple, you should be consuming 1gram of carbohydrate per Kg of body weight per hour. You can achieve this by consuming any high carb/low fat food, energy bars, gels and drinks. Once again, you MUST avoid fat, because this will slow down the absorption of carbohydrate significantly by putting a nice fat cork into the gastric emptying process.

 

Drinks or solids? Well, this depends on the weather and your perspiration rates (as we discussed in the previous article). If it’s hot and you’re sweating a lot and therefore losing water, you should drink a lot of energy drink. If an energy drink is mixed at 6%, you’ll be consuming 60grams of carbohydrate per hour, just by drinking a litre of it and this will keep you hydrated too. A 9% solution will deliver 90grams of carbohydrate per litre. On the hottest days of the year, most of you should be able to achieve your carbohydrate goals by drinking a 6% solution; you’ll just need to focus on regular drinking. If it’s cold like it is at the moment, drinking this much will just fill your bladder on a regular basis and much to the aggravation of your buddies, your ride will be rather well punctuated with inconvenient comfort breaks. This is where solid food like energy bars, gels or high carb/low fat snacks will come in. Drink less and eat more, so that you’re getting the carbohydrate you need, but not over-consuming on fluid. Once again, the free TORQ Performance Resource outlined above goes into much more detail on this.

 

3)     Improve your fat burning: This may sound like a contradiction in light of my suggestion earlier that you can’t burn fat without carbohydrate, but it isn’t.  Referring back to the earlier diagram, one gram of carbohydrate will provide about 15 times more energy when burnt with fat and oxygen through aerobic metabolism compared to anaerobic metabolism where the end products is Lactic Acid (the stuff that hurts your legs when you go up hill).  So, if you can develop your aerobic system and get a higher proportion of your energy from it, you’ll last longer without bonking. This is why some people can seemingly ride forever without bonking – it’s just that they’re working aerobically and being extremely efficient in their carbohydrate usage. If you’ve got a well-developed aerobic system it will mean that you can ride fast for long periods of time without bonking and if you’re the kind of person that plods along all day, while others race up all the hills, but they all bonk before you, this is because you’re working aerobically albeit at a low power, whilst all the others are tearing each other’s legs off in anaerobic bursts and emptying their carb stores. It also therefore stands to reason that if you want to survive a very long ride without bonking, as well as getting your nutrition right, you should ride steadily and consistently, not in bursts.

How do you improve your aerobic power and fat burning? We’ll discuss this in a future article, so I won’t go into too much detail here, but it basically involves riding for long periods of time at a relatively low intensity (about 65 to 75% of your maximum heart rate). It can be about as interesting as watching your spouse peel sprouts at Christmas, but it does the job (I get so bored watching, I decided it would be motivationally advantageous for the two of us if I were to help her – does that make me a 21st century man, or should I be doing it all while she sits and watches me?). If you can combine this kind of riding with your mixed paced group rides, it will make a big difference to your endurance.

 

The whole point of this 3-pronged attack is to prepare you so that you don’t bonk, because prevention is certainly better than cure in this particular case.  If you bonk in the future, it’s likely to be down to lack of preparation and complacency more than anything else.  And if you do bonk, you’re pretty much at the point of no return I’m afraid.  By getting some carbohydrate in, you’ll start to feel less faint and dizzy, but the damage will have been done.  All the energy products in the world won’t be able to afford you much more than a crawl.

It’s worth noting that if you’ve got two or more D-days lined up in a row, like if you’re going away for a weekend’s riding, your carbohydrate intake immediately after the D-day 1 ride is extremely important. You want to get something high in carbohydrate and low in fat down your neck within 15 minutes of finishing, because your carbohydrate processing mechanisms are in overdrive at this time and you’ll store a lot more of it than you would with an equivalent feed later on. There are some bespoke recovery drinks on the market that will do this really well, but at the very least, have an energy drink or some high carb/low fat food with a cuppa as soon as you can. For the keenies among you, aim for 1gram of carbohydrate per Kg of bodyweight again if you want to ensure you’re getting enough. Then start getting the carb calories in to load up for the next day.

Just in case I’ve caused a bit of an upset with my drinking water/ecological rant earlier on and you’re beating yourself up over drinking tap water and potentially contributing to Armageddon, please note that with respect to water, whatever goes in must come out, so I was only joshing with you. Drink as much as you like – it won’t hurt the wildlife unless you choose offload the contents of your bladder down a foxhole. And so that we don’t get dentists writing in, please remember to clean your teeth after eating all that carbohydrate!

Best of luck with your D-day(s).