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Friday, December 23, 2011

Long Runs - Long Rides and their effect on fat and carbohydrate metabolism

Hi Gary,

Thanks for your time. I recieved your e-mail address from your website after reading Keith Livingstones book on Lydiards principles. Am so very happy to be able to ask you a question

In the book Lydiard principle recommends doing long runs with no carbs. I'm a cyclist trying to use his principles, and on the bike a long equivalent ride would be 5hrs or so. Would you recommend going this long also without carbs? Can only manage 3.5hrs at the moment but am working on it.

All other areas look as though they can transfer across ok :)

Many thanks Gary, take good care Clarence 
Clarence, rather than muddle about trying to explain what can be quite confusing; especially since what we are saying seems to run counter to "mainstream" advice, I decided to ask the author of the book, Dr Keith Livingstone, to do the honours of providing the answer.

As an aside; Keith and his twin brother, Colin, were born in Kenya and raised in New Zealand. In their 20's Keith and Colin were more like rockets than runners. While I can claim to have done some training runs with Keith, I saw mostly his rear end while he set about innocently wasting me!  Keith was one of the most promising 5 and 10km runners during the 70's but he chose study over running which was a good decision - I guess.  Keith is a bit of a bright spark and he knows his exercise physiology back to front, especially as it applies to running and cycling.

Just one further comment from me: What Keith explains below may appear to be running contrary to what most mainstream nutritionists and exercise physiologists tend to advise - like loading up on carbs here, there and every-where.  I think the root cause of this dissonance in advice is because the food industry has captured academia and the media: Research that sets out to prove the benefits of hi-carbs gets the funding and the ones that produce findings in support of carbs gets all of the publicity.  The rest get buried - if they ever get off the ground in the first place.  Over 70% of academic studies never see the light of day and fewer than 10% of these ever get published in a peer reviewed journal and then only a few of these get into the popular press - and this is after the funding bias in favour of carbs has done the first weeding out!  You see; the food industry want you to buy highly priced super-processed foods (if you can call this food!) that are made from super-cheap stuff like soy, corn and wheat extracts.  There is no money to be made by trying to sell you a corn cob.  The money is in taking that raw 10 cent corn cob and converting it into several sports gels and selling them to you for 2-5 bucks each.  Got the idea?

In my book Healthy Intelligent Training, I advised runners that they SHOULD NOT try to do their long runs by running the last few kilometers by sucking on carbohydrate gel sachets, etc.

Why would I say this? Surely that heavy-legged, wooden feeling we get as the last of the accessible carbohydrate stores gets used up isn't desireable, is it? Well, in a circular way, yes- it’s extremely desirable. There’s really no better way I know of to get the body to switch its attention to conserving glycogen (stored muscle sugars in endless chains of glucose molecules) than by taking that tank to ‘empty’ a few weeks in a row in long efforts until the body then says “But hey- I can MAKE more of this stuff by stripping down fatty acids into glucose by another route!”

(“Triglycerides”, which are often represented as “bad fats” by people who should study and think more, can be considered “Three -glucoses”. With a twist of a bit of each end, and a ‘yank’ between each section, done in the machinery of the slow twitch fibers’ mitochondria, in each of those fatty acid molecules there are a few potential high-energy glucose molecules once they've been cleaved off and re-badged.)

A body trained this way on the Lydiard principles will soon adapt, and the “heavy-legged, wooden feeling” doesn’t occur at all in long runs over two and a half hours any more. In fact, one starts to move along at very good high-aerobic speeds on a mixed-fuel of carbs and fats, just about as efficiently as on carbs alone. This leaves decent stores of muscle glycogen that can be accessed late into a long aerobic race like the marathon, or late into a competitive ride, without the need for “gu-gels”, etc. If you train to get super-efficient on dual-fuels, and hop into a race , you can always “top up” within the race for a superlative result (maybe a big negative split!). However- practice it once or twice outside a race just so that you don’t have any surprises on race day!

So if we can find a way to ‘train’ the body over a number of weeks in incremental steps to strip down the nearly endless supplies of free fatty acids floating around, and re-badge the ‘triglycerides’ that make up a high proportion of accessible fats within the muscle cells into glucose for higher-power output, then we’re using the metabolic portion of the slow twitch fibers to supply ready fuel for our fast twitch fibers that supply the power necessary to move anyone at much faster than 4m20s Km speed.(8.5 mph for a runner).

On long runs, we should make an effort to stay hydrated , because glucose needs a fair bit of water around it to get into the system. The way to get things going when running is something like a 3.5 hour run with the first 90 minutes at slow jogging pace, and then do a normal 2 hour run on top of that, and see how good you feel at the end.

On long bike rides, the trick is to never go off the small front ring on a road bike, and ‘spin’ for as long as possible at low intensities, with the heart rate quite low, near only 65% intensity on the Karvonen Heart Rate scale. (Gary explain this.. it’s in the book- I’m going to bed). (Gary’s advice: Read the book!)

On other rides through the week that have different purposes to the fat utilisation purpose of the long ride, naturally enough we go at sustained intensities that are higher, to our level of training and tolerance.

The great, and very very big Miguel Indurain, one of the few multiple winners of the Tour de France, gave Lance Armstrong this low-intensity tip as more or less his ‘secret’ to conserving muscle glycogen. On the big front ring, we can push higher speeds for sure, but it’s done by utilising higher power output that tips the scales towards more fast twitch fibre use, and thereby ripping through glycogen stores. Since we do much the same amount of nett work for a given distance, whether we do it with high speed and high power, or whether we take it a little steadier, the small front ring and lower heart rate will make sure you’re using slow twitch more, thereby stripping down those triglycerides and free fatty acids in the mitochondrial energy factories without touching your glycogen stores much.

As a rule of thumb, the more strength or power required to turn the pedal, the more the likelihood you’re recruiting fast twitch and using glycogen, and vice-versa with respect to the far more aerobically efficient and fuel-efficient slow twitch fibers.

So if your ego can handle fat weekend warriors with spare tyres passing you on the waterfront, start there, but also be prepared for the odd granny to go past. Then you’re really doing it well, and after your fatty acid metabolism kicks in, you’ll find you can go a very long way without the need for carbs.

HOWEVER- always have some carbs on hand just in case your system isn’t quite right one day and you ’bonk’ thirty kilometers from home! I’d also suggest eating every couple of hours after about 5 hours if you do longer rides; toasted sandwiches of cheese, ham, and tomato were perfect fuel for me when I did a few all-day charity rides several years ago, as well as a water-pack with grape juice (alkali, full of potassium) diluted by about 1:3 with water. Fruit juices such as apple or grape are alkali (= good!), whereas orange juice is too acidic and can muck up your stomach quite badly. Any fruit drink should be diluted to roughly 6g sugars/liter (6% w/v), or less on hot days.

Keith Livingstone
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The advice in these articles is given freely without promise or obligation.  Its all about giving you and your family the tools and information to take control of your health and fitness.

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