Can I run as fast on fat as on carbs?

I was watching the diamond league athletics on the telly last night and wondering, could I still run 400 meters in under a minute? When I was a boy I had a PB of 55 seconds. And 4 years ago pre-LCHF I clocked 62 seconds after an ill-advised bet with with my son; could I still get anywhere close to that?

The stock answer to the question "Can I run as fast on fat as on carbs" tends to be that the fastest runners are all fuelled primarily by glycogen, not fat. This may be true, particularly as they all tend to be young and insulin-sensitive; they are suited to running fast on carbs. Most of us are neither of these.

But where is the line between carb-speed and fat-speed? According to Tim Noakes this line is probably only a few minutes back from the leaders of a Marathon, or a few seconds for a 10K.

And so the number of people for who the stock answer applies is actually tiny. Look at the details of elite low-carb runners and you will see that they run sub-2:30 marathons and 30 minute 10ks. How many people do you know who can do that?

What I hope I have proved on this blog is that for everybody else it is possible to train ourselves to run just as fat on fat as we could on carbs. See this post for lots more detail on how we can train our bodies to run fast on fat.

Perhaps there is a competitive advantage to the shorter, faster races from burning carbs, but again, how many people does this apply to? Unless you are a track running member of an athletics club or still at school then it is very unlikely that you will ever run a fast 400 meter or mile race again (I'd put the parents race on sports day in a separate category here!). In which case this advantage is of no consequence, you could run just as fast on fat as you could on carbs.

And so the big question should really be, why would I want to run on fat?

Well my answer to this question comes in two parts:

• As a runner I am much happier and feel more consistently energised when burning fat. I also don't have to carry anything on long runs which is rather nice.
• As a human I am convinced that the older I get the more suseptible I will become to insulin resistance and the risk of obesity or diabetes is just too great.

And as for the standing quarter in under a minute. I am confident that I'll do this down at the track one evening this autumn.

24 hours of Endurance

I haven’t been posting much lately. Minor injuries led me to withdraw from the Brighton Half and full marathons this spring and so I have been focussing on something a bit different, a 24-hour relay. Our village running club We Run! Hassocks entered 4 teams into the Endure 24 event, a 24 hour relay over a 5 mile course. We entered one team of eight, two teams of five and a solo. I was to be in a team of 5.

We Run! Hassocks

There are a number of firsts for me here; running at night, camping and running, running with little or no sleep and running at a decent pace several times over a long period. Previous experience at the South Downs Way Relay was useful but that was with a bigger team and much less distance. We reckoned that the faster team of five might complete perhaps 7 laps each. I have not run this distance in a single day for over 6 years now.

Once again I figured that energy intake was to be the key factor determining my ability to keep running at the same pace over a 24 hour period. There is no real difference here between running on fat or carbs but with fat having more energy in I reckoned I’d not be needing to eat so much as the others and hence I ought to be able to feul a little more comfortably.  Another issue was to be that one of our team would not arrive until 10 pm as she had a wedding to attend; so with less than 3 hours between each run I’d need to get some food down pretty quickly after each one, including during the night when I am not used to eating at all.

Part of the fun of these events is the camping. Our gang of 20 or so had camper cans, a caravan, a mess test and several smaller tents, all bunched up together amongst thousands of other runners and a 5 minute walk from the start/finish area. Many of the gang got there on the Friday and made camp. They had a jolly social evening but an early bed-time. I did not get back from working in Paris until the Friday night and arrived shortly before the start of the race on Saturday lunchtime.

I had had to curtail a run in Paris on the previous Tuesday after a pain in the thigh after just 5 miles, so I was feeling anxious as to whether I could complete the challenge and desperate not to let the team down. The weather was expected to be warm with a high chance of severe rain!  I’d packed for the worst, including full rain gear and 5 running shirts. 

Up the long hill on lap 2

My first run was lap 2. Like Nick before me I went off rather faster than I had planned. I had figured I ought to be able to keep going at 40 minutes per lap, or 8 mph for each of my laps but I ran the first in just over 35.  I spent most of the time worrying about my leg and not watching my speed, but I was pleased that everything felt fine and was not too tired when I headed back to camp after exchanging the team wristband. Then I made a big mistake, after a quick stretch I sat down and ate, and rested; and after an hour or so my right leg was as stiff as a plank. I hobbled around a bit and nothing improved. I hobbled to the start of lap 6 and nothing improved. I felt like I was going to be unable to run and I’d let everyone down already.

I started lap 6 at walking pace with my leg hurting, but when I broke into a jog things got better. After 5 minutes I was up to cruising speed and feeling fine. It’s all well and good “listening to your body” but when it is telling you the wrong thing sometimes you just have to force the issue.  Lap 6 turned out to be quite quick; I even took 2nd fastest time of the year on one small Strava segment.

From then on I kept moving, not sitting down for more than a few minutes at a time and gently massaging my legs frequently for the next 20 hours. The stiffness never came back.

Laps 10 and 14 went well. I felt strong and kept having to remind myself to slow down.

Now I was starting to feel tired. Not so much from the running but from the time of day. I am not a night owl and I generally want to be in bed by 11, but I didn’t want to seize up again so I forced myself to stay awake with coffee and conversation. The other runners were coming and going from the mess tent throughout the night and so there was always someone to chat to. At midnight we made coffee for Janna our solo runner who came in for a rest after completing her first 10 laps.

A team of 1!

Lap 19 was my first ever night run. I’d been obsessing about my head torch which always slips off but one of the gang suggested I use a running cap to support it. This worked well and I also carried a powerful hand torch that I had bought for a tenner off ebay the previous week. I expected to run much slower in the dark but as soon as I got moving I felt fresh again in the cooler night air and the route was lit-up my my lights and those of the others around me. 

There are several very fast teams in this event and I was used to being overtaken perhaps four or five times on each lap by faster runners. On the night-time run I was rather chuffed not to be overtaken at all.  Despite the need to tread carefully, particularly in the woody sections, I managed the lap in 39 minutes.

Our fifth team member had turned up by now and she very kindly did 2 laps in a row twice at night in order for us to rest a bit more. Unfortunately one of the team had to pull out after four laps and so we were back to a team of four.  I tried to sleep for a couple of hours but I think I was too wired to rest. I was up again at 4 a.m for my next lap at 5. Dawn was breaking and there was a double rainbow over the woods as I headed off on lap 25. This meant rain. But thankfully the forcast storms didn’t materialise and we just got a few comfortable drizzly showers during the rest of the day. Again I felt strong although I’d not slept now for 24 hours. I may have been a little weary but I didn’t feel any lack of energy.

My contribution to the group camping was to cook breakfast bacon for everyone. I topped up on fat with eggs and creamy coffee and felt strong. Over breakfast we did the maths and realised that we were on time for completing 34 laps. This meant 8 laps each for the slightly faster runners. 40 miles!

It’s interesting how the mind works; during the night I had been thinking “just 2 more laps after this one”, but when it came round to each lap I was ready to go and I know that I could do more if needed.

Lap 29 went similarly well. There was just the one point on each lap that I rather dreaded. “Heartbreak Hill” as it was termed lay 3 miles into the route, it is just a 30 meter climb but it’s sharp and hard on the quads. By now I was one of very few people still  running up this hill and I was determined that I ought to be able to do so on every lap. It did hurt though. Luckily I had sussed out the route and my plan for each lap was to start out gently up the long hill, speed up for the next 2 miles, take it easy up heartbreak hill and then go fast back down to the finish. The route was on tarmac, gravel paths, grass paths and a little rough woody path.  I think that the mixture of terrain and pacing helps dispel the monotony and helps the legs too.

One more lap to go. For a while we wondered if by pushing harder for the last 4 laps we might get in just under 24 hours and get another lap done, but we realised that this was not on, so we relaxed; we each had plenty of time to complete our last lap. I intended to go more slowly, honestly! But as soon as I got going after a slow climb to the top of that first hill the love of competing took over again.

I tend to run slower than some uphill and faster than most downhill in order to maintain an even effort just below my VO2 max.  A young chap raced past me on the hill but didn’t really pull away, and that to me represents an unavoidable challenge!  I sped up slowly on the flat and downhill sections and passed him before Heartbreak Hill, and then I didn’t see him again. I still felt good and I was nearly home now, so I raced back down the hill to the finish where I handed over to Helen to run the last lap. I didn’t need to race; there was no one fast to race against and it made no difference to anything, but I enjoyed it immensely all the same. 

Finishing too fast?

One of the big rules of running fuelled by fat is not to actually run out of glycogen. I’ve talked about even tempo before and it helped me at Beachy Head. The liver can keep making glycogen in small amounts and so if you preserve it your brain should be fine. But burn it all up in one mad dash at the end of running 40 miles and perhaps your brain will complain. Mine did just that.

I had a drink and stood around at the finish smiling for a few minutes but my heart rate did not come down. In fact it rose from about 160 to 180. And I was very hot. That was not good. I had some more drinks and took my vest off to cool down. After 5 minutes I thought I was improving and put my hoodie on, the “Fuelled by FAT” one that I like to wear at events. And then I nearly collapsed. I was stood looking faint and wobbly when some of the gang turned up to watch the12 o’clock  finish. “I know what you need” said Ginnette, “Sugar!”. They all found that rather amusing but she was right. I was marched to the Cliff Bar tent where I had a couple of their fruity jelly fuel cubes and a minute later I was right as rain!  I felt like I’d been in a practical science experiment studying the brain’s dependency on sugar; and it reminded my of the finish at my first  30 miler 10 years ago when the St John’s Ambulance guys dragged me into a van and force fed me sugar and oxygen (they were rather over-zealous I'm sure), or the day I collapsed a mile from the end of the Month Blanc Marathon; brain gone.

It has been a few years but once again I’d hit the wall. Luckliy I hit it and the end of running 40 miles, not 20 miles earlier!  Lesson re-learned though, when running on fat we have to be very careful not to burn out; study your own performance and when running endurance events always run within your current ability; or if you must race at the end of an ultra, then eat a banana first!

Still harping on about Cholesterol Malcolm?

I think that by now most of my friends have had 'the cholesterol chat' with me; in pubs, over dinner or even sometimes when out running. I am generally careful now to only harp on about this to people I have not met before. This blog is an exception.

I am not a medical person, nor a nutritionist (although I did follow a correspondence course last year), and I hope I know where to draw the line between my knowledge and that of others. I do happen to know a little about statistics, something that helps to understand the relationship between a health claim and the data that apparently supports it.

But cholesterol is one subject that I have taken a close interest in. The reason for this is that it lies at the crux of the health/diet debate; it has had a massive impact on public health and the practices and finance of the NHS.

When I first saw the FSA video that declared that saturated fat clogs up your arteries just like it could clog up a drain pipe, I was scared; clearly that was the intention. And for many years I lived in fear of my higher than normal cholesterol leading to an early peanut butter induced heart attack.

That said, the concept did seem a bit preposterous at the time.  Humans have always eaten saturated fats and as far as historians can say is seems that we have not always dropped dead of Coronary Heart Disease. Also, the fat in the video only clogged up when it got cold, and human arteries are well known to be warm places!

The fear of fat was created in the 1970s and 1980s when firstly US dietary advice and then the advice we received from the NHS was changed. Very few scientists agreed with this change at the time, but Kellogg's were pretty happy about it all. We all switched from eating real natural food to eating cheap cereals instead. And we started adding more and more sugar to everything in order to make it more palatable. And did we get healthier? No, we did not.

Then along came statins (or did they actually arrive earlier looking for something to cure?). A panacea, no longer even requiring full clinical trails as they meet the simple surrogate endpoint of lowering LDL cholesterol. The claims were that thousands of lives would be saved, and yet the data quoted at the time showed that only small numbers of lives (perhaps 1 in 200) of already ill people might be prolonged, for a short while. Lives were not saved. I get incensed by such things as this. Data like this is being used to support the notion that we should nearly all be taking a drug that has several known side-effects and has clearly ruined the lives of many many people.

And the more I've learned about cholesterol, "good or bad", the more I have become convinced that there is nothing in it. For every report that declares that high LDL will lead to high CHD there is another that shows that there is no causation. The most obvious data here describes whole populations with low LDL and high CHD, high LDL and low CHD. How could this be?  Malcolm Kendrick sums it up perfectly (again) in this article where he points out that Russian men are eighteen times more likely to get a heart attack than Japanese men, and yet their average cholesterol levels are the same. This whole series of Malcolm's articles makes very interesting reading if you have an interest in heart disease.

If we can remove statins, cholesterol and hence saturated fats from the whole heart disease debate then we can start looking at the relationship between health and food in a different way. Fats and carbohydrates both provide us with energy, but which are more healthy and which are making us fatter and unwell? And in my opinion a big clue lies in this simple question - which is the only macro-nutrient that in its natural form has no nutritional value?

Eating to Run

Last month the Food Programme on Radio 4 ran a 2-part series entitled Eating to Run. Naturally I was intrigued and listened in. The program covered a wide range of topics with a focus on how the food we eat can impact on our performance. 

• They spoke to expert sports nutritionists at Loughborough University about the right balance of macros and foods for elite British athletes.
• They spoke to Brendan Foster about what he ate when he was breaking world records. Toast and honey.
• They looked at what the world’s best marathon runners form Kenya eat (mostly rice and potatoes), and the diets of the running mad Japanese who eat a lot of fermented foods and run a lot faster than we do.
• They spoke to Scott Durek, perhaps the worlds most gifted ultra-distance runner. He advocates a vegan diet with lots of fermented foods as this improved the efficiency of the gut.
• And they briefly described Tim Noakes and the LCHF diet. Noakes was the great pionner of nutritional research for performance running and he now admits to have got it all wrong.

Lots of people advocating hugely different diets. And loads of contrasts; the scientists from Loughborough insist that you need to burn carbs and you need to recover quickly with a protein and carb drink; and the Kenyans (who happen to be rather better than the British) who eat nothing at all after a long training run. Brendan foster replenished his body with a couple of pints of shandy!

And the conclusions that I come to are these:

Eat whatever works for you and your body, but make sure you are not harming actually yourself.

I believe that a lifetime of high carbohydrate food is likely to contribute to bad health, especially if you are intolerant to carbs as many people undoubtedly are.

I also believe that most of the science described by sport nutritionists and quoted by Lucozade is aimed solely at elite athletes.  And as Charlie Spedding puts it so well in his biography entitled Last to First: "Why is it that most of that fastest British marathon runners in the last 40 years were running over 20 years ago?"  (In 1984, for instance, 2hr 15min was broken 25 times by British athletes. In 2012 it happened on just three occasions).  Something is not right here.

The notion that we must run on carbs in order to be champions relates to a tiny fraction of runners; and except for sprinters the rest of us could certainly run just as well on fat if we chose to and would be best off considering what energy source is more healthy. And the answer to this would appear to be to “Eat Real Food, mostly vegetables and not too much”.