Friday 13 September 2013

Fat Burner - Part II (I'm a freak)

In November last year, I had a test done.  It was a test to see where I was in terms of how I use fuel during exercise.  The thinking was that I'd like to try to optimise to burn as much fat as possible and as little carbohydrate in order to make race fuelling easier, both in practical terms and in terms of being easy on my poor stomach after the experience I had in Bolton in 2012.

I turned out to be a reasonably good fat burner and I used the numbers to test the theory at the London Ultra in February this year.  Wind forward a good few months and I wanted to see what, if anything, had changed on a diet that had evolved a little to between 50 and 100g carb a day rather than the draconian <50g a day I started with last year.  I was slightly apprehensive that the slipping into very weird habits (eating cake a couple of times a week when I've never been that much of a fan!) and going a bit off the leash on a semi-regular basis since starting a new job in March might have ruined things a bit.

So... this stuff is both simple and complicated at the same time.  You may already know a lot of what I've written below, but here it is just in case.  (Also lots of it is very personal to individual circumstances, genetics etc. and lots of it/almost all of it has not a lot of hard research behind it, but we do the best we can.)

The simple bit is that the "best" way to improve your fat burning capability is in a gentle and controlled way. Just go out and run/cycle.  Even with all the technical information in the world at your disposal, there is nowhere near even 1% of the information we'd need to get this sort of thing absolutely right without some empirical, individual experimentation.  i.e. go out and do longer and longer runs at the target pace, carry emergency nutrition with you, but aim to complete the run without consuming it.  If you hit the wall, obviously eat/drink.  Take note of the results.

The complicated bit...

In general:-

  • When exercising, your body will use a mixture of fat and carbohydrate to fuel the effort.  The ratio varies with effort level.
  • Untrained endurance athletes will rely quite a lot on carbohydrates for fuel and the mass-market advice to consume 20g carb every 30 mins (or whatever it is) is a good safety net to avoid bonking/hitting the wall.
  • Untrained, not highly-dedicated fat burners will have a secondary problem to the physical wall in the mental wall too which is also physiological in root as it relates to what fuel your brain is using.
  • The human body contains approximately 2000kcals (varies mainly by body weight) of accessible glycogen (metabolic by-product of carbohydrate which the body uses for fuel, and more slowly generated from protein if there's insufficient carb available).
  • There is a hardwired limit for people that does not allow glycogen depletion beyond a certain level - i.e. some people can deplete to 20% remaining, rarely down to 5-6%, some are less lucky.
  • There are two or three points in the heart rate range where the ratio of fat to carb dramatically changes.
  • There is a point at which the effort level is so high that a body is using 100% carbohydrate to fuel the effort.
  • Taking in carbohydrate replenishes glycogen stores, but it takes a little while to process (20+ minutes depending roughly on GI)
  • Taking in protein replenishes glycogen stores but much much much more slowly than carbs.

Most of these factors may be altered through nutrition and training.  The "may" is more than likely genetic and there's not a lot of info about on the likelihood of whether a person may be able to alter the factors, but it appears that the majority of people who end up in elite/professional sport are able to and do do so to some extent or more.

The effort level for a given ratio of fat to carb can be altered/improved by any or a combination of these things over a period of months:-

  • Fasted exercise sessions - e.g. do a morning run before you have breakfast.
  • Add a little caffeine into your daily routine; can be very effective in combination with the above point.
  • Change your general nutrition plan to keep the amount of carbohydrates low or very low (the absolute threshold will vary from person to person.  For example, I seem to be able to "get away with" around 100g carbs a day, whereas some seem to need to keep below 20-30g a day.
  • Change your general nutrition plan to keep the amount of fat in your diet high or very high. Again the percentage will vary from person to person, but I hover around the 70-80% range.

From personal experience, I have found the first and last points to be the most effective in moving the thresholds in the right direction for me.

If you are particularly keen to switch your brain fuel from glycogen to ketones (i.e. from carbs to fat) you would have to be very very harsh with carb restriction; usually under 30g a day for around a week or so; during this time you're likely to feel fuzzy in the head, irritable and need more salt than usual.  The general effect of switching brain fuel is twofold: you reduce the impact on your emotional wellbeing when you do push hard and run out of glycogen, and secondarily it appears that you may be able to then access more of your body's glycogen stores and deplete them even more than usual when your brain runs on ketones.  Again, from personal experience I have bonked on a very low carb diet (after 6 days training camp, doing approx 8 hours training per day) and instead of wanting to sit in a corner and cry, I just couldn't get my legs to go at the speed I wanted them to, no pain or distress, they just refused to go quickly.  A much less stressful result.

If you have the time, spare cash (around £165) and/or inclination, you can get a test done, like I did, that gives you an idea of the ratios of fuel you personally burn and at what effort level the ratios change appreciably.  It's called a "gas analysis test" or "metabolic efficiency test" and the test is done on a bike or treadmill while strapped into a mask over your mouth and nose.  You start off at an easy pace for a warm up, then the recording starts of your heart rate, pace/wattage and the amount of air going in and the volumes of CO2 coming out.  The effort level gets increased every few minutes in steps to a reasonably hard level but not absolute maximum (this is not a "max test") and then the data collated and analysed.  You can then do some calculations on how long and at what effort you could safely run without needing to top up the stores and if you do need/want to top up you can work out how much and how often.  This is what I did for my 50km Ultra race in February and I calculated that at a heart rate of around 160BPM I could conservatively go for 6 hours before I might need to top up.  I ran the race at a HR of around 170BPM in 05:50 and kept pace the whole way around, no sign of legs ignoring me.  Oh, and I didn't eat anything at all, despite well-stocked aid stations full of goodies!

Now in the test last month, the numbers went in a good direction even further.

I'm burning 100% fat right up to a heart rate of 165BPM (on the bike) now.  That's 87% of my max heart rate (on the bike).  That's pretty phenomenal.  In theory, as long as I keep my heart rate under 165BPM, I could ride pretty much forever on my stores of body fat and not need to eat anything at all.  Apparently, this is fairly uncommon.  What's also uncommon is not switching fully to carb burning at high effort output - known as "going anaerobic".

The additionally interesting bit comes from the carb burn and how that varies, as that will tell me ballpark rates at which I get through my body's stores of glycogen and then at what rate I would need to replace them at in order to maintain that level of output.

OK, so the graphs aren't useful for working that out, but the numbers are and the headlines are:-

How long I have on stored glycogen (conservatively)
How much carb/hour I need to refuel, after running out of glycogen

So... in practical terms, what I'm normally doing now is eating my usual low carb/high fat diet right up until the morning of a race.  On that morning, I'll have a breakfast (3-4 hours before the race, so if an afternoon one, then adjust the time to match) of scrambled eggs, with avocado and cream cheese, or cured meats with boiled eggs and cheese, with a mug of tea - very my normal breakfast! During the race, I'll have water with electrolytes and that's pretty much it.  On a very much longer session/race I'll take something if I think I might just get hungry (cheese/nuts/cured sausage) and a fuel bar or two for emergencies (something like a Clif bar).  I raced a half ironman a couple of weeks ago and ate nothing apart from one speculative gel at the start of the run course, because I hadn't gone through the new data properly yet - turns out I didn't need it (lots of analysis around pace and heart rate during the race confirms that well enough for me to be happy with that).  And I raced pretty hard, so I'll take that as an encouraging data point for me.

What I'd say, to others who want to take steps into this stuff, is that if you have a few months to try things, do that and see how things feel - don't be afraid to add in a bit more carb on the day of the race, your body will use it unless you're pretty much walking the whole thing or are very very highly trained and run very slowly for your ability.  If you don't have a lot of time, I'd say have a normal breakfast on the day of a (longer) race and if you feel you want the safety net during a (longer) race, try something more natural with minimal sugars, or even home-made fuel bars where you can control the ingredients to things you know are fine for you.

For me... this all means I can experiment a bit and play it pretty fast and loose with taking on carbs during higher effort training and racing.  I've heard a number of accounts that state that once you're actually exercising, you don't suffer the usual difficulties related to insulin responses to carbohydrate , though there are some that say you need to be careful as if you do stimulate high insulin response it will interfere with your fat burning capability during the exercise.

At the end of the test, looking at the initial numbers, the tester summarised with "Endurance. The longer the better. You will have a phenomenal advantage."  Along with "Those results border on the freakish, I've rarely seen anything more extreme."  *beam*

Thursday 12 September 2013

Race Report: Racing the Valencia F1 Circuit

Thanks to Virgin Active, a bunch of Team Freespeed went down to Valencia to race the Valencia triathlon at the weekend.

A week after Ironman 70.3 Zell Am See, Mr TOTKat and I would have just about enough time to get over lead-legs and needing to sleep a lot, and get out and race an Olympic distance with a good degree of fitness and energy.  We swapped bikes in the bike boxes, TT bikes out, road bikes in - Valencia is a drafting race so TT bikes aren't allowed (or rather, long aero bars aren't allowed as they're pretty dangerous at close-quarters riding).  Plenty of clip-on, stubby aero bars in evidence at the race, but I'll get to that in a bit.

We flew out on Friday morning from Gatwick and into 28C an sunny skies in Valencia - gorgeous!  The forecast was for cloud and still warm across the whole weekend, so no need for a wetsuit (though we both packed one, just in case) and no need for socks apart from the fact I really want to be sure my feet are good for the next few weeks into the Rotherham 80km Ultra marathon.  Fun and games at the airport with 9 people and 5 bike boxes to get to the hotel and only normal-sized cars as taxis.  No mini-buses, no people carriers.  We managed somehow and got to the hotel, which was really lovely and welcomed us with cava and orange juice as well as little gift packs with maps and travel passes in them.

A little unpack, then off for a swim down at the beach and back to the hotel for an early night.

Next day we put bikes together and headed out down to the sea front to have a look at the race expo.  Not so many vendors there but a few stalls with general sports kit and the registration tents for when that opened later on in the afternoon.  Back to the hotel for a huge nap and then out with the other guys again to register and rack up bikes.

Sunday morning was an earlyish start at 6am to get to transition before it closed at 07:45 in time for the first race start at 8am.  I popped into transition to set up my shoes, helmet and take the plastic cover off my bike that'd been protecting it from the potential rain overnight.  I said I'd take the plastic cover off Matt's bike for him so he could have a nice lie in for his race start at 10:30 so I did that and checked his tyres were OK - they were.

Mr TOTKat was due to be off at 08:20, so those of us off later went to check out the swim course while he got ready to start and then watched the swim leg for the first few waves and then saw Matt burning off the front of his wave before Jenny and I headed to get ready for our start.  We were herded into the start pen for a pre-race talk; 5 minutes in Spanish, no English for the International athletes.  Oh well!  We then plopped into the water, which was gorgeous temperature for swimming in!  It was so very very salty too.

Bang went the start cannon and I tried really hard not to just mow over the row of women in front of me who were really slow, but got over the reticence and got on with it.  It really wasn't very fighty as deep water swim starts go, just a little jostling at the start then I had clear water.  Having recced the swim course earlier, we had a great idea of how to sight for almost all of it and I put some good effort in for the first few hundred meters before easing off a bit, slightly distracted by the salt water in my mouth.

With the beautiful water, the temperature and the freedom of just a tri-suit maybe, the swim felt really really easy.  I didn't put a whole lot of effort in, if I'm honest, but it turned out I led the second pack for quite a way until getting under the bridge for the final few meters and a couple of women overtook me, and I let them as I wasn't sure where the exit was so I'd rather follow them.  I scrambled out, up the ramp and jogged the long long carpet through to transition and around to where my bike was racked.  On with the helmet, race number, socks (paranoid about blisters at the moment), bike shoes, sunglasses, unracked bike and jogged with it to the bike exit.

Over the line, mount the bike and clip in.  I heard cheers from the spectators of "Go on Kat!" etc.  I guessed that was Nick and Mr TOTKat as he'd've finished by now.  Start to pedal as I just hit the left turn for the bridge and *THUB*THUB*THUB* er... not a good noise.  Stop, unclip, feel back tyre - fine, feel front tyre - flat as a pancake.


My repair kit was not with me, having lost a chunk of it last week at Ironman 70.3 Zell Am See I'd not replaced it yet and decided not to carry a reduced kit for an Olympic distance race.  I unclipped my other foot, dismounted and hugged the fence back to transition against the flow of other athletes.  I had to find a race official, to withdraw from the race so they wouldn't worry about a missing athlete.  I found one with a radio and made the international sign of the glum face and pointed at my dead wheel.  That worked.  Mr TOTKat had by that time made his way level with where I was and shouted that I should use his repair kit from his bike.  I politely declined at that point - it'd've taken me ages to find his bike, get the kit and wrestle the still fairly new tyre off and by that time I'd've lost over 10 minutes and I'd be the last person over the finish line.  I didn't much fancy that and I'd had a lovely swim, so why get cross and have a horrible run by myself in the blazing sun when I didn't really need to?

I racked up my bike and joined the boys to cheer the rest of the team home over the line.  Turns out I was 3rd in the Vet Females in the swim.  Which was nice.

Matt won the Veterans race, and Jenny was 4th woman overall and 3rd in the open women's race.  Pretty darned good for her seeing as she'd had the twins only 10 months ago and not been able to train for a long time!

All in all, I really enjoyed the race and the weekend.  The swim was really very nice and although it was a shame not to have been able to ride the bike course, there's always another year and we'd be more than happy to go back again.  The short of it, the Valencia Triathlon is a good 'un and at a good time towards the end of the season to keep spirits up in the sun.

[Thanks to Nick for the use of all of his photos in this article!]

Nick on the camera bike

Tuesday 3 September 2013

Race Report: 70.3 Zell Am See 2013 - I have never raced so hard

Cutting the long and boring flights story short; we arrived and our bikes didn't.  They weren't loaded onto the plane at Heathrow when we were and arrived at out hotel at 6pm on Saturday.  Thankfully, we had some advice from a friendly MC we know (thanks Paul!) and a quick chat with one of the organisers gained us permission to rack up in the morning - thank god for the race start being from 10am!

So, most of Saturday was spent doing a fat lot of nothing, accompanied by ze alcoholfrei, which the Germans & Austrians seem to do really rather well and with copious choice.

Nice and early to bed and as we were settling down, we heard a weird noise.  It sounded like a cross between an air-brake and a high-powered water hose.  I got out of bed and walked towards the window then realised, as I got level with my bike, that the noise was coming from my back wheel and it was air rushing out of the inner tube into the deep-section rim.  (See in the photo below the thick bit of black on my back wheel - the valve extension goes through that from the inner tube and out so you can attach a pump to it.)

Time to whip out the tyre levers and fight off the still relatively new tyre to replace the inner tube and/or find out what was going on.  Thankfully it was nothing bad, just the rubber at the join between inner tube and the valve had failed.  So all I needed to do was replace the inner tube.  I say all... with deep-section rims as deep as this, you have to use valve extenders and seal them in with PTFE tape; of which I had none.  Cue sitting on the floor and crying.  Mr TOTKat was a total hero, and a lot calmer, he let me have one of his spare inner tubes which had an extension pre-taped to it for field repairs.  Sorted.  Back to bed.  Sleep.

Up at 7am (lie in!) to get some brekkie and go to rack up at 8.30am as agreed with the race officials.  All went smoothly, nicely checked in and racked up.  It was raining lightly as forecast.  Mr TOTKat  was due to start in the first wave at 10am and I was 25 minutes later in the "all women and relay teams" final wave.  We kissed and he headed off for race start while I tried to keep from getting too cold by hovering in the cafe area, having already handed in the street-wear bag with shoes, socks and warm clothes for after the race packed in it.

Time passes.

(Thorin sits down and starts singing about gold.)

10:25 and I'm in the water (which is nice and warm at 19Cish) and the cannon goes off to start.  And I make what I think is the most accurate route to the first buoy I've ever managed in one of these races.  No feet to draft off, which was a shame, but a straight line out for the 890m or so to the first buoy, no argy-bargy at all and none really around the turn point.  Felt a bit sick, but that usually happens when I'm trying reasonably hard, so I ignored it.  Dead straight again to the 2nd buoy another 230m so onwards and the nausea I'd had for the first leg wasn't fading.  I just thought I was putting in some good effort.  Turning the 2nd buoy I couldn't see where to aim for and am pretty sure this third leg wasn't all that straight.  But, I overtook an awful lot of people from the earlier wave in their yellow hats.

Up the steps, yanking at the arms of my wetsuit which is a sod to get over elbows and wrists... to the carpet through to transition, to grab blue bag, get out of the wetsuit and into bike kit.  I'd packed light for this race as it was never going to be that cold, so all I needed to do was put on race belt, glasses, helmet and bike shoes (yep, I still haven't got around to learning to mount the bike into shoes that are clipped into the pedals).  Even if it rained really hard, it wouldn't matter - no point wasting time and effort putting on rain jackets or long-sleeved tops on the bike as the rain was probably going to be pretty hard and I'd only end up with a lot of wet fabric clinging to a lot of my body, making me really cold.  I did shove my remaining bike tool into my back pocket and then as I was trotting to the bike mount line I thought I'd dropped it and spent a good few seconds worrying and looking, but gave up pretty quickly - no replacement inner tube, no tyre levers, no pump.  Plenty of mechanical problems I could fix with that little multi-tool, but I'd just have to live without it.

The bike course was wet, it rained on and off, but mostly on and I got cross with a lot of people.  There was drafting galore and blocking.  The course may well be technically quick, but you'd need to be familiar with it.  There aren't that many straight sections, there are some, mostly out around Piesendorf, and it's narrow in places, with wooden bridges to cross too.  It is pretty darned flat though.

Still.  I overtook A LOT of people.  Including a GBR male age-grouper who may have been having a bad day. (I looked him up afterwards, he started the race 15 minutes before me and was 25-29, poor pup!)

Strava estimates my highest average wattage of any ride I've ever done:-

Compare a reasonably hard training ride with this race...

80km training ride in the UK
90km race in Austria

and again...

80km training ride (no I don't think I actually hit 74.9km/h - mad thing!)
90km race
Putting aside the well-organised draft trains and blocking from a certain Austrian age-group female, it was the hardest effort I've put in on a bike ride.  Ever.  By the end of it, my quads were pretty unhappy and as I reached the dismount line, I had to hold onto the hedge to unclip my second foot.  I then burst into giggles as I could barely walk, never mind jog through transition.  Guess what?  I still felt pretty sick.

My auntie was there at the entrance to transition, waving and cheering me on (thank you for travelling 200km on that day to see me for all of a few minutes!), so I gathered enough beans together to jog really slowly through transition, my legs feeling like two logs strapped to my backside, flapping about underneath me.

T2 was just as simple as T1.  Bike racked, bike shoes off, helmet off, number belt swung around to the front, visor on, running shoes... oh!  Oh man!  My feet were covered in grit from the bike course.  Really scratchy grit.  So, I used about half of the water in my bike bottle to wash it off as best I could before putting on my running shoes.  No way did I want grit in my shoes for 21.1km, stripping the skin off my feet.

I chugged the remains of my bike bottle, ditched it into the red bag, grabbed 2 gels and ate one.  Off out onto the run.  Just about to exit transition I felt something banging about in my back pocket - my bike tool!  I was drawing parallel with where the blue bags were hanging up so I thought I'd drop it off in my blue bag.   I just couldn't find it though, so left it on the ground at the side near the bags and hoped it'd be there later.  Off out over the timing mat now and up the long spur out to the 3x loops.

Starting out on the run, my legs were pretty shot.  They felt like lead - never have they felt so awful from bike to run.  And within the first kilometer, my right inner thigh just above my knee (around the end of my VMO) started to niggle.  Within the first two kilometers I wanted to stop or at least walk.  I was pretty broken.  It took a lot to keep moving.  My first boost came from one of the couple we met the day before the race when they didn't have bikes arrive either.  The chap gave me a good shout out and it helped keep me going.

Up into town and onto the loops.  Winding around town and out along the lake side, each km seemed to take forever.  I felt ill still and that gel had done nothing for me.  I struggled to keep my legs moving as they started to hurt more and more.  There were a couple of little rises in the town and a dip under a bridge which made walking more and more tempting.  I made a deal with myself to walk the aid stations to drink water as I'd only had 1/2 a bike bottle so far, the rest going over my feet to get that grit off.

Plenty of support out on the course, lots of bells, whistles and "hop hop HOP!" from the supporters.  Lots of "go on Kate!" when they saw my race number and I passed the lady of the other late bike couple twice and each time she gave me a good old shout out - I could do no more than grunt.  It hurt.  My legs really really hurt.  I passed Mr TOTKat  for the first time (going along the bit where you meet people on another part of the lap) and he shouted out to me, giving me the fight to keep going some more.  I didn't think I'd see him again before the finish line.  Then more support from familiar faces, Freespeed team-mate Declan gave some great encouragement right on one of the little rises and I simply didn't recognise him the first time.  I was in quite a dark place with sore legs and continuing rising ill-feeling.  Added to that was quite a hot spot in my left shoe, but I was ignoring that.  I'd felt worse and it'd been fine before.  The temptation to stop or just walk was huge.  The bad voices in my head kept saying "What's the point, hundreds of people have passed you anyway; you're not going to get a podium place anyway, your run is far too weak for that and you went too hard on the bike. Why bother?  Just walk...".  Those voices are the ones that make you slow down, or give up.  You have to ignore them if you want to achieve your goals.  Have to.

By the third lap, I felt pretty awful in the guts and had no idea why or how I was still going.  To my huge surprise, I saw Mr TOTKat  again and realised either he was having a terrible time or I was having a great one (it turned out to be the former) and then Declan and other familiar faces again.  The final run back from the far end loop the sick feeling reached a peak, I let out some wind and then... realised I needed one of those portaloos.  Right.  Now.  Except I was way past them and there was nothing but path, grass, lake and the odd tree.

Not Good.

I walked a little, hoping it would ease, but there was no stopping it.  I found some sort of tiny bush, better than nothing, and yanked down my shorts.  A passing athlete asked if I was OK and I grunted a "yes" as I sympathised with Paula Radcliffe rather deeply.  It was that or basically run with shorts full of poo.  And I mean -full-.  I felt quite a bit better after that and got my act together for the last couple of km to the finish.  A couple more bits of run/walk and with my three lap counter bands in place, the fourth time through the band gates meant I could go left and hit the final 100m to the finish line.  Grim determination made me run that last 100m and I crossed the line, bent my head for my medal, was wrapped in a foil blanket and then collapsed at Mr TOTKat, saying "I couldn't have given any more".

And despite my usual post-race over-analysis and self-criticism, I really believe that.  On that day, I could not have given any more.

It turned out that hot spot in my shoe was a problem and the blood soaked through my shoe.  I sweated, bled, cried, and worse for this medal.  But I did it honestly, unlike many out on that bike course - the only sour note to the day.  12th in my age group, but an age group twice the size of any other Ironman branded race I've done to date.  Best placing in age group in an Ironman branded race, best time in a 70.3 by 36 and a half minutes, and the first time I've really left it all out on the course in any race.

And all for this medal.

P.S. a little comparison with Galway, the race that wasn't.

Compare Zell Am See (above) in 2013 with Galway in 2012 (below).  The coloured bands are set at the same thresholds of heart rate (ignore the drop outs for Galway, my strap was less reliable then and I forgot to turn it off at the end - actual race time was 06:18:58).  Much more effort.  Much less crashing and breaking bones too :o)