30 April 2013

An attempt to run a marathon using SCIENCE: part XII

So after running a marathon you get really lazy. Too lazy to do the washing up, or walk down the stairs at your flat to put the recycling out, or change out of your pyjamas before the postman arrives... Your kitchen sink slowly disappears under a pile of unwashed mugs used to eat chocolate gateau out of and you have to force your way through mountains of unrecycled cardboard to get to the bathroom. When you can be bothered. So, yeah, definitely too lazy to write blog posts.

I'm exaggerating a teeny bit. Something like that happened for a couple of days and then, lo and behold, the SUN came out! And I had my trainers back on in a flash. The mental recovery was probably harder - my brain went into a flap for about a week afterwards, wondering what it was supposed to focus on after all the training and menu plans came to an end, and all the niggles and sniffles that threatened to ruin the race magically disappeared. Then there was the Boston Marathon thing, which felt strange and horrible while I still had my own marathon in my legs.

Anyway, here's a picture of me running a marathon:

I know! I even look like I'm enjoying it!

I won't bore you with the details of the race. Suffice to say it was rather hillier than expected - a two-lap course that inflicted some severe psychological torture between 20-30k, when all the hills from the first lap reared their ugly heads for the second time around. On reflection, a time of 4:02 was respectable and, hey, I have this nice picture that will no doubt lead me to remember it as being all lovely and smiley and even repeatable in the not-too-distant future...

So what have I learnt? Has SCIENCE taught me anything about running a marathon? Did it help?

I guess I should really have run a marathon *without* the SCIENCE first... as a control. But that would have made for an equally poor experiment. I think you learn so much by doing all the training and running the marathon, that a second marathon will always be easier anyway, no matter how much expertise you throw at it. For example, next time (ha!) I would be much more careful about my tapering - not just cutting down on the mileage for the couple of weeks before the race, but avoiding *anything* untested. (I stupidly had a go at some 100m relay reps the Wednesday before - "it's so short it couldn't possibly hurt!" - not thinking anything of it until I woke up the next day, three days before race day, with some very tired thighs). There was also a lot of trial and error that went into planning my pre-race meals. Not particularly scientific either, just seeing what would get me up in the morning feeling energised rather than sluggish. (Brown rice rather than pasta, if anyone's interested, but that's just me.)

On the subject of nutrition though, I do think that reading some of the literature on carbohydrate storage and "the wall" helped. Otherwise, I think I would have been pretty skeptical about using energy gels. Sports drinks, I've concluded, are largely useless in the context that they are used by most people. But a marathon is a special case. You simply can't run on empty. So I spent a long time researching energy gels and tried out everything I intended to use on training runs before the race. As a result, I never hit the wall... and managed to avoid throwing up on a grass verge as I saw several runners doing.

High intensity interval training at the track has also helped me increase my pace. As coaches keep telling me, there's plenty of evidence for this type of training improving your speed endurance, but I'm not sure whether the effect has been largely physiological or psychological. (I *believe* I can run faster, so I do?) And I reckon the major benefit has been over 5k and 10k rather than longer distances. Still, who knows? It might have taken me 10 hours to finish the thing without all that HIIT.

There were other aspects of endurance running and training that were not particularly well studied. I remain unconvinced by evidence on yoga, cross-training and stretching, for example. The problem is that there are just so many variables... Every study tries something different - different exercises, at different frequencies, with people of differing abilities. It becomes impossible to make comparisons. And most studies are small. With runners so stuck in their ways, convincing more to take part in scientific studies is a challenge because it means messing with their precious training regimes.

I think there's an important lesson to be learned from all this. You can't rely on science to tell you what to do. It doesn't have an answer for everything - well, not yet. People have been running marathons for a long time. People who run them and people who train other people to run them know what it takes, even if they haven't tested it on hundreds of people and published it in a scientific journal. And everyone is different. What worked for me almost certainly won't work for everyone else trying to run a marathon. On the other hand, you can save yourself a lot of money and wasted energy by being skeptical and looking up the evidence that is available (or not available, in many cases). If someone tells you to wrap your feet in newspaper and stand on your head for half an hour every morning to cure your plantar fasciitis, try putting it into PubMed before you do it.

Oh dear - look what happened over that second lot of hills!

6 April 2013

An attempt to run a marathon using SCIENCE: part XI

The important business of the day: WHAT AM I GOING TO WEAR? Currently, it could be either of the following two outfits...

It's April and due to the Great British Weather there's no telling whether we'll have sunshine or snow next weekend, but if like me you're marathoning for the first time this month, I have one piece of advice: DO NOT run in something you haven't tested out beforehand. Don't even think about it. I made that mistake in a race once before, so this time I've tested two new pairs of shorts in near-freezing conditions, just in case we have warm weather on the day. Since we've had few opportunities for warm weather training, temperature will unfortunately be a worry if it heats up in the next week... but at least I won't get caught out by chafing or embarrassing wardrobe malfunctions.

As far as the SCIENCE goes, I'll leave my results and conclusions till after the marathon. For now, here are some quite staggering statistics courtesy of my Garmin watch.

Since the start of the year...
  • I've run 585 km (not including warm up/down)! That's the distance from Torino, Italy to Aix-en-Provence, France. I know, I have NO IDEA where that is either.
  • I've run 6.10 km per day, or 9.29 km on each run if you discount rest days. WHAT? I am NUTS!
  • I've spent a total of 66 hours 35 minutes and 17 seconds exercising, not even including all the nasty hurty stretches the physio prescribed. That is nearly three whole DAYS! And I bet I've spent twice as long analysing my Garmin stats...
  • I've used up 28,069 calories just on running. Man, I could have eaten a LOT more cake if I'd thought about it.
I am never doing a marathon again.

Anyway, there's one more thing I want to share with you before I do this thing...

15 years ago, my dad made a bet with me. A bet worth one thousand English pounds. Next Sunday, my dad will lose that bet - albeit a few years later than I intended - when I complete my first marathon. Sadly, he won't be well enough to watch me run and I won't be claiming my winnings. Actually, I'm sure he hasn't given that bet much thought since the day he made it. I asked him a couple of times if he had any recollection of it and he told me he didn't. But no matter. What he said provoked in me a fierce desire to show that I was stronger and more determined than even he knew. That's why when I'm running I'm often thinking of my dad - not in defiance but with a sly smile that says, "I told you so." I hope he'll be proud that I proved him wrong.

2 April 2013

An attempt to run a marathon using SCIENCE: part X (Rest)

My race number arrived!

This week I've been getting to grips with rest. In the practical and the academic sense - while winding down ("tapering") my training I've been devoting some time to theories about *when* to rest. Common sense dictates that your rest day should be the day after your long run. For me, that's usually a Monday, after a 20k or 30k run on a Sunday. However, there are some running bods who would advise me to delay my rest day till Tuesday. Why? Surely it would be madness to run again the day after a killer 30k?

 As I've been finding out, there are plenty of dubious reasons to delay your rest by one day - cleaning out clogged systems etc - but a few days ago I came across this post referring to Matt Fitzgerald's book Brain Training for Runners, which offers an immunologically-founded scientific explanation.

Now, I like immunology. I was such a nerd about it at university that I took *Advanced* Immunology as well as ordinary, boring, easy immunology. And I got top marks. YEAH. So as you can imagine I was pretty excited to hear this explanation.

Ben at Ben's Book Blog has helpfully copy and pasted page-referenced sections of the book if you're interested. The gist of it is that immune cells produce a molecule called IL-6, which is released during long, exhaustive bouts of exercise and is involved in the body's adaptation to endurance training - suggesting it would work to enhance your marathon performance. Therefore, running again while IL-6 levels are still high should offer some training benefit.
"IL6 is believed to facilitate many of the body’s adaptations to exercise training, ranging from increased fat burning to greater resistance to muscle damage, to improved cognition." (Fitzgerald)
Sounds like SCIENCE. Except... "believed"? Could it be just another dubious theory? What worries me is not so much that the theory could be wrong, it's that runners are being told "don't give yourself a well-earned rest the day after a really heavy training session, go back out for more punishment..." The IL-6 theory has been used to support a training strategy known as "bonk training" (ahem), supposedly practiced by elite athletes, but certainly by diet and exercise obsessives looking for quick-fix solutions.

"Bonking" approaches involve running before breakfast or within a few hours of a long run, to get your body - in its state of depleted energy supplies - to shift from burning sugars to its back-up fuel, fat. At the extreme end of the scale, bonking means pushing yourself through "the wall" to a hypoglycaemic state where you feel sick, dizzy and fatigued. As those who read my second marathon post will know, I experienced something like this a few months ago due to misjudging my nutrition needs on a long run and I DO NOT recommend it. It is neither pleasant nor safe, especially if you are running on your own.

Right. So let's break down this IL-6 business. What's IL-6? It's a signal protein that tells your body - primarily your immune system - when it should be doing certain things. We've known since the early nineties that IL-6 is released during lengthy exercise. We also know that it's released when levels of glycogen - a stored form of sugar that you keep in your muscles and liver - are low. Makes sense, right? Energy levels are going to get lower the longer you exercise.

There are studies, in both humans and mice, showing that IL-6 increases up to 100-fold during extreme exercise. Here's one showing that IL-6 levels increase after running a marathon. It's thought the molecule is released by contracting muscles, as well as the brain.

So what happens when you run on already low levels of sugar/glycogen? What is IL-6 telling your body to do? What's the training benefit? It's not so clear. Despite evidence suggesting IL-6 is involved in fat-burning and the body's response to muscle damage, there's still a lot we don't understand about this molecule. In a 2012 study, Danish researchers wrote:
"it is evident that exercise training has beneficial effects on [fat] tissue inflammation and overall [fat cell] function... but it is not known whether IL-6 contributes to such training-induced adaptations in adipose tissue."
In the same paper, after summarising the results of some experiments in mice, they went on to suggest that IL-6 mediates effects of exercise training on fat tissue. Regular training seems to result in *lower* resting levels of IL-6, potentially balanced by increasing levels of receptors producing greater sensitivity to the molecule. But what does it all MEAN? Does running on IL-6 teach your body to switch between fuels? Does it make you fitter? We don't really know. Not only is research pretty early stage, it is published post- the initial hype about bonking and Fitzgerald's 2007 book... Even in 2012, the science of IL-6 was still dodgy.

The picture gets even more complicated when we appreciate that a good deal of the research in the field of IL-6 and exercise comes out of the lab of a minor celebrity scientist at the University of Copenhagen whose reputation appears to have been somewhat blemished by accusations of scientific fraud. "Leading" exercise researcher Bente Klarlund Pederson has written several books (in Danish, I can't translate) about exercise but recently found herself under investigation after a paper she co-authored with colleague Milena Penkowa was retracted.

As far as I can see, there just isn't enough evidence yet to cement the link between IL-6 and any training benefit in endurance runners. It's just a theory. We seem to be back to the same problems I've been coming up against with most of the exercise research I've looked at in this series - the studies are too small and too few. And in this case, they're not necessarily in runners/humans. I was able to track down a relatively recent paper in the Journal of Sports Medicine and Physical Fitness (October 2012) focusing on a study in 16 male runners, which showed that IL-6 levels remained elevated up to six hours after a 90-min run - although I can't get at the full paper because of annoying PUBLISHING REASONS. Anyway, the authors didn't translate this result into training advice, which seems perfectly sensible given the thin evidence base.

Personally, I think it's silly - you might say BONKers - to suggest running on empty, especially if we're talking about only a few hours after a long run. Or to base your advice on one molecule... which might or might not be beneficial in this situation. I imagine there probably are benefits, adaptations, whatever, to this type of training (through the IL-6 route or otherwise), but there may also be risks - like keeling over and DYING. Which, I distinctly remember saying, was something I wanted to avoid.

Also, if running on IL-6 did have some training benefit, presumably it would depend on levels of the molecule remaining high until your next run. In other words, not replenishing your carbohydrate stores, which would bring IL-6 levels down again. So, what, I'm suppose to come in from a 30k run on a Sunday, eat bacon for dinner (or, I dunno, something else devoid of carbohydrate) and then head back out on Monday morning? Pah! Thus I am going to continue taking a whole day's relaxing break every Monday and use it to stock up on lovely, lovely carbs. So there.

As for rest in the more practical sense, the hardest part of my training is now over and, so far, tapering has involved eating almost an entire box of chocolates in one weekend (it was Easter) and getting into the studio at 10.30 this morning. (Despite what you might think, keeping lazy working hours is not standard practice for freelancers. And I haven't worked in my pyjamas *once* this year. Okay, maybe once.)

12 days to go!