Fueling for endurance events - Part 1

A few days ago, I was browsing around and came across a blog post by TJ Tollakson - the person who won the Lake Placid Ironman in 2011.  To be honest, I normally don't read much on these things because they usually talk about stuff that doesn't much apply to me, and things that are only interesting to those who are elite athletes.  I figure they get enough attention, they don't need mine.  This time, however, it was different.  I'm not sure whether it was because I saw him cross the finish line in person, or what - but I was compelled enough to read it.  Or at least, to start.

It started out like I'd expect - events he did leading up to IMLP, fancy equipment too expensive for me to afford but that would help his time, yadda yadda yadda - but before too long, it started getting interesting.  He started detailing what he ate before, during and after the event.  Suddenly, there was something he was writing about that I could relate to.  I may not have the training, equipment, or inherent talent that he does - but one thing I can optimize is how I fuel during a race.

My plan for IMLP in 2012 has always been to take full advantage of the support.  They will be having sports drink available every 10 miles on the bike, and every mile on the run.  My plan was to down a 24 oz bottle of sports drink at least every other aid station, and possibly grab half of a banana at the other stations - something like that.  That would equate to 24 oz per hour of sports drink, minimum (at my pace) - and plenty of potassium.  Normally I don't end up consuming quite as much on my rides simply due to logistics and availability of water.  Then, on the run, I'd grab some more during my walk breaks every mile.  In fact, I was figuring I'd be better hydrated and energized during that race than at any point during my training.

So, back to the blog post - what really stuck out to me, after reading all the stuff about a gel every 20 minutes, having caffeine halfway through the bike, was the comment that he got off the bike and felt almost as fresh as he did at the beginning of the bike.

Let me repeat that:  He finished a 112 mile bike ride, and still felt energized enough to, as he put it 'rock a solid marathon'.  The fact that he did the bike ride in a stupid-fast 4:33 (25 mph on one of the hilliest IM courses in the world) is just gravy on top.

I think that stuck out to me because I don't care who you are or what training you've had - you are going to feel a 112 mile bike ride.

Now, obviously his power output on a bike far exceeds mine, for a multitude of reasons:  he's got a coach (I don't), he's got a tri bike (mine is a road bike), he's trained far more than I have, he's an elite athlete (I'm an average Joe), etc, etc.  The list goes on and on.  But that list is a list of things I cannot change (well, realistically, anyway - I'd like to keep my day job and continue living in a nice neighborhood).  What he did do, though, is make sure he was loaded up with fuel.  That is something I can change.

A few years ago when I started this whole triathlon thing out, my friend Dave convinced me pretty quickly how important sports drink was for endurance.  However, I didn't put a whole lot of stock into the number of calories, because it seemed a small fraction of how many would be needed.  For example, you have a marathon at 26.2 miles.  For most people, thats going to equate to about 3300 calories required for that effort.  If you drink 24 oz of sports drink per hour, and it takes you four hours - you end up with 96 oz of sports drink.  Most drinks are about 50 calories per 8 oz, so you end up consuming 600 calories.  Sure, 600 out of 3300 is a decent percentage (about 18%) - but it certainly isn't where the vast majority of calories are coming from. 

Now if you look at TJ's calorie consumption - he ate 15 gels in the 4.5 hours of the bike.  Cycling requires significantly fewer calories per mile than running; running generally equates to about 125 calories/mile, and cycling is often closer to about 45.  Sure, each of those vary from person to person, and the numbers vary with intensity and equipment - but we are ballparking here.  So each energy gel is 110 calories - meaning he consumed over 1600 calories on the bike alone. 

So, the rule of 24 oz of sports drink per hour  provides 150 calories of fuel per hour.  TJ consumed about 360 calories per hour on the bike - more than twice the caloric intake.  That is a significant difference. 

But that's not all.  In my recent exploration of fueling for endurance events, I browsed through the 'Running for Fitness' link that I have on the sidebar of this blog.  This was an example of a page I stumbled across before, found it imformative, and just flagged it for review later without really processing what it had to say.  I found section 7.3 - "Energy While Running", and suddenly a bunch of things started clicking in my head all at once:

"You can store about 400g of glycogen in your muscles, and about 100g in your liver (though, as we shall see, these can be increased with training). This means you can store about 2000 kcal as glycogen – enough energy to run or walk about 20 miles."

Well that there pretty well explains the dreaded wall at 20 miles for a marathon.  However, my wall ocurred a few miles later during the Baystate Marathon .  I only consumed a total of 48 oz (6 x 8 oz bottles) of gatorade during that marathon, which accounted for about 300 calories (or 2.5 miles).  In fact, its worse than that because I mix gatorade at about 2/3 to 3/4 strength.  But either way, the timing of when I hit the wall vs how many calories I consumed is just about perfect.

"The aerobic energy system primarily uses a combination of carbohydrates and fat (but can also use proteins). The proportion of carbohydrates and fats used depends on the intensity of the exercise. For low intensity exercise, your muscles mainly draw their energy from fat. But as your effort level goes up and your muscles have to generate energy more quickly, so you have to increase the proportion of energy that comes from carbohydrates. The proportion of energy provided from carbohydrates rises as exercise intensity increases from around 10% to up to 90%."

My HR during that marathon was generally between the 75-85% range.  So if the amount of carbohydrates required goes up with intensity (up to about 90%, where it switches from aerobic to anaerobic), then I was in a mode where the majority of my calories needed to be carbohydrates.  That leads back to the previous point, where I only provided my body with an additional 300 calories of carbohydrates.  In effect, I was starving myself of carbs.

Then there was this bit that started to tie it all together (bolding mine):
"During the first hour of exercise, most of your energy comes from glycogen stored in your muscles. After about an hour, the muscles begin to draw their fuel from the blood sugar, which is in turn supplied by glycogen stored in your liver, as well as from their own stores. Your liver glycogen levels are also finite. So when your liver glycogen is depleted, your blood sugar level falls and you are unable to carry on exercising. This low blood sugar (called “hypoglycaemia”) induces a feeling of tiredness and light-headedness, and your legs begin to feel very heavy. Marathon runners know this as “hitting the wall” or getting “the bonks”. It is a quite distinct (and unpleasant) feeling, and it has the same effect on your running performance as a large bear climbing on to your back.
But if you can replenish your blood sugar while you are exercising, you will not deplete your liver glycogen stores so rapidly, with the result that you can carry on for longer before you hit the wall. That is why it is a good idea to take energy on runs of more than 2 hours."

This is where I got into forehead slapping territory.  Durrrr... Just one of those moments when I realized that all those times during long training runs that I felt like I was running out of gas - it wasn't that I needed more training to push beyond the limits I had found.  I just needed to do a better job of fueling my body.

Then, finally, there was these bits in the last section:
"Research shows that the average person’s muscles can take up about 30g to 60g an hour of carbohydrate from the bloodstream."
--snip
"It takes about 30 minutes for the carbohydrate which you eat or drink to reach your bloodstream, so you need to start consuming carbohydrates before you begin to feel tired."
--snip
"consume about 35g of carbohydrate per hour, which will roughly maintain your blood sugar levels."

Thats a lot more carbohydrates than I've been taking in during long runs and bike rides.  The problem I had was that during bike rides, opportunities to refill water bottles in order to consume that many carbs in the form of gatorade were relatively few.  This has me thinking that I might have to re-evaluate how I get carbs during long rides and runs.  It may be that energy gels are a higher density form of carbs that can more easily be consumed in the proper amounts per unit time.  Another option might be to go with gatorade full strength (or even more) - but honestly that gets too sweet, and I know that I'll be wanting nice cool, fresh, unflavored water on those rides and runs in the middle of summer when it is hot out.  So I think that possibility is off the table right away.

I'm starting to see why they say that sports drinks are good for anything over an hour, but not necessarily for the long haul as the primary form of fuel during a marathon.

Coming up in the next part - now that we've established the importance of fueling during exercise, we take a deeper look at fuel sources.

Day 53 - 10 mile threshold - 12/29/11

Although I normally wouldn't do a second threshold run in one week, I really wanted to experiment with some homebrew energy gel, and today was the only day I could do it in the near future.  The full story on the energy gel will be detailed in the next post - but the short version is that I've been looking into nutrition, specifically how to fuel for endurance events, and have had my eyes opened somewhat.

Today's run was a repeat of what I did earlier in the week.  During that previous run, everything felt generally fine until about mile five, when I could tell the wheels were starting to get squirrely.  Then around mile eight, I pretty much bonked and had nothing left in the tank, unless I really wanted to make recovery absolutely miserable by way overdoing it.  But then again, I didn't bring any water or anything with me.

So I bundled up in my cold weather running gear (complete with newly gifted blinky lights, and a headlamp that we've had but I never actually used), 4 x 8 oz bottles of water, and a 5 oz flask of homebrew energy gel.  I was concerned about the gel and its fluidity, due to the temperature.  I started out thinking I'd take some every half mile along with a swig of water - but quickly realized that due to viscosity, squeezing it out of the tube was so distracting that I'd be better off taking some every mile instead because that would minimize the distractions.  I'd just end up taking more, thats all.  It ended up working decently well - I thought I had finished with the majority of the gel consumed, but once it got into the house and warmed up a tad so that it wasn't all stuck to the walls of the squeezable flask, it turned out I only eaten about half of it.  Oops.

Regarding how well it worked - most definitely an improvement.  I felt fairly strong throughout the whole run - going up hills were not as fatiguing, I recovered faster, overall HR was decreased, had no problems with bonking out.  If I was out of gas last time, this time I'd say I finished stronger and still ha probably 1/3 of a tank left.  Enough to push the pace up for a few miles at the end if I was running a full half marathon, but not so much left that my overall pace could have been significantly faster

After reviewing the results, two thoughts come to mind.  Having something to top off energy glucose stores during exercise definitely helps with maintaining a fairly strong feel throughout - and the gatorade I've typically been having in the past was helping far more than I ever thought.  I always considered it primarily hydration and electrolytes, and it is both those things - but I didn't realize the tremendous effect that the sugars in it also have. 

Day 52 - P90X Back & Biceps - 12/28/2011

Writing this a day late.  In fact, I got a few posts to write up tonight.  I'll be in front of the computer for a while.

Anyhow, this time around on this routine I had gotten a new set of barbells that are easier to switch weights out.  They also came with weights in lb increments, instead of kg's.  So, now that I have four barbells total - all of them adjustable (two quickly adjustable, two are a pain in the ass) - I was able to enhance this workout a bit.  In the past, I had to keep switching between weights that were appropriate for bicep work, and then switch them out for weight appropriate for back work.  This resulted in excess downtime between sets.  However, this time I was able to set one pair of barbells up with heavier weights for back stuff, and one pair of barbells up for biceps.  I ended up going with 16 lbs for biceps - which I figured would be just about right for some things, and maybe a tad light for others (based on previous workouts) - and 14 kg for back stuff.

It turned out that those weights were just about right.  One thing I didn't anticipate was the difference that the extra rest between sets had previously made.  This time around, since the sets occured one after the other with much less rest, it turned out that the slightly lighter-than-expected weights for biceps was just about perfect.

So, overall - some of the numbers are down from last time (like only 6 total chinups, and 2 corn cob pullups towards during the max rep set at the end), but I think the reps and weights from this time around are much closer to what they should be.  It also means that the results are likely going to be more repeatable week to week. 

Day 50 - 9.5 mile threshold - 12/26/11

Not really sure why I bother keeping track of the days anymore.  With the warm weather, it's not like I've been concentrating on P90X as much as I anticipated.

The past couple days I've done a couple runs around the neighborhood with the dogs again.  I mostly wanted to see how my right foot acted after some slow, easy miles during a run lasting between 30-60 minutes, with the primary stress being two days in a row.  So there was one run on the 23rd (day after my last post), followed by a rest day on the 24th, another easy run on the 25th, and a threshold run today.

Unfortunately, there was both a good and a bad.  First off, the good: the right foot hasn't been a problem, even with running two days in a row, twice, with only a day in between.  With the total being over 20 miles during that time, I'm pretty happy about that.  Also, I am still able to put up a decent performance during the threshold runs in terms of pace and sustained HR.  The bad: there are more and more signs that the very low amount of running over the past couple months is taking its toll.

Part of it, honestly, is my own doing - today was a day of throwing in a few variables that were detrimental to performance.  First, I went out with no water, gatorade or anything.  I knew I was going to be out for the better part of 90 minutes or so, but for whatever reason I just didn't feel like getting all that stuff prepared.  Second, I tried playing with the workout feature of my HR monitor - setting it for one mile of a warm up (which I defined as a HR of less than 155), followed by 8 miles of a HR between 158 and 172, followed by a cooldown mile of a HR less than 150.

The workout experiment lasted all of about 1.25 miles.  While I went slow, and the average HR during that mile was 144 - right about where it should be - the damn thing was so sensitive that it was beeping all over the place.  Go up a tiny hill, it complains about the HR being too high - and that first mile, while certainly not describably as being 'hilly' - has a few gentle inclines that tend to bring the HR up briefly.  After I got past the warmup mile and into the threshold, the HR monitor was then, almost immediately, complaining about HR being too high - as it was registering nearly 180.  I know what a HR of 180 feels like, and I wasn't feeling that.  Soon after it settled back down and registered a more accurate reading in the 150's.  Not sure whether electrical interference was a problem (I've had interference with Polar HR monitors, but never the Forerunner), or weather it was poor conductivity of the chest strap - probably the latter - but either way the thing was complaining.  And since it was complaining, I slowed up a bit before I realized it was registering high - so of course once it started reading correctly, my HR went below 155 and it started complaining about that.  I ended up saying 'screw it' - I didn't want to listen to this thing yapping at me the whole run.  In the past I've tried playing around with these kind of workout features, and just found them too inflexible.  I wish they'd use some sort of averaging algorithm in order to determine when to scream at you, as opposed to the instantaneous HR.

Anyhow, I stopped the workout, but that of course screwed up the whole standard I follow of autolapping every mile.  So it ended up being about a 1/3 of a mile off on every autolap.  Not that big a deal, really - just annoying.

So then once I got off workout mode, I was cruising along pretty decently, but it didn't take long for me to start whether I really had the stamina to keep up the pace.  I was hovering around the 8 min/mile mark and a HR of 160 for most of the time - which I was happy about because I've certainly sustained that HR (or higher) for distances longer than this run - however I didn't know whether my mind was playing tricks on me with regards to endurance, or whether I was actually exerting myself more than I should have.  At around the 5 mile mark, I pretty much had my answer - I was starting to feel the effects of pushing things, and I knew I was only halfway done.  Also, most of that first five miles is relatively downhill - not a whole lot, but I knew the last half was going to be slightly uphill.  It was at this point that I realized not bringing gatorade or at least water was probably a mistake.  As the next three mile wore on, the rate of exhaustion grew as well.  By the time I hit mile eight, I had spent a few miles in the high 160's for HR, and was feeling pretty cooked.  I slowed up a bit to recover, thinking maybe I'd treat the rest of the run as an interval workout, but I couldn't really even muster up the energy to do that.  I decided that this workout was done, and I'd slow up and give myself a nice and long cooldown.  If the run was somewhat of a fail, I didn't want it to spill over via soreness and tightness.

I'm hoping that in the next week or so, I can find a chance to do that loop again, but I'll bring gatorade with me.  I'd be interested to see what difference in makes - I feel like it'd make a significant one, but I'm also basing that assumption on results from a couple-few months ago, when I had been better about keeping up with running 3x per week.

Day 46 - 5 mile run and P90X Chest, Shoulders and Triceps - 12/22/11

Today, in an effort to condense three activities into one, I decided to try bringing both dogs along with me for this run.  In the past, I've run with one of the dogs, but stopped because having to deal with pit stops and other stuff was distracting for a run where I was trying to actually accomplish something.  However, today I had no real goal - I just wanted to run an easy 5 miles or so - so I figured I mine as well try getting exercise for me and the two dogs all at once.  I set out on a course around the neighborhood, which ended up totaling about 4.75 miles, so it was a little shy.  It was a distance PR for both dogs.  They made no attempts to cover it up either - during the short walk back to the house they were lagging behind a good amount.

For the P90X workout, this one is still pretty rough.  Part of it is that I have 8 lb dumbbells, and I've been going with 6 kg for most of the exercises, because switching out weights is a hassle.  So although 6 kg is a bit much for some things, such as the later tricep extensions - I am finding I'm making progress.  Whereas before the weight was so much that form was sloppy AND the exercise was difficult, it is starting to get to the point where I can pay attention to mechanics and form a bit more.  Granted, it is still rather sloppy, and the reps are few - but it is at least going in the right direction.

One more workout for this week (Back & Biceps) and then Phase II is done, which means a week of rest.  W00t!

Day 44 - P90X Legs & Back - 12/20/11

I just realized - I never made an entry for yoga yesterday. Probably because there was nothing much special to report on. Except that it gelt hotter than it's ever been. It seems I've said that probably 4-5 times, but I can tell you with certainty that this time felt hottest. Fortunately, I've learned how to pace myself so that I don't burn myself out.

My biggest hope for the class was to see it set my right foot back to normal. One of the ways I can tell how inflammed the tissue is is during some of the kneeling poses - when my ankle is at its greatest point of flexion, and my weight is on top of it. If it hurts when the pressure is released, I know inflammation remains. Fortunately it was only a mild annoyance on the pain scale, so the hope was there. Even still, this morning and throughout the day today I popped ibuprofin and aspirin - thinking that maybe if I kept the inflammation down in the first place, it wouldn't get worse. That experiment is still in progress (more on that later).

So tonight was the legs & back workout again. Increase weights on a few of the exercises, and managed a total of 74 pullups - so that number is slowly increasing by a few each time.

Hmm.. not much to say other than that. Tough to always come up with something to say with strength training - I lift things up, and put them down. Or, rather, in this case - I go into a lunge, and come back up.

After that workout, I started experimenting with another treatment for my foot (maybe this entry should have been titled differently?) - alternating cold and hot. So while I watched some TV for about an hour, I dunked my foot into cold water for 5-10 minutes, followed by dunking it in hot water for 5-10 minutes. The idea is that cold constricts tissue and cuts out inflammation, but then the heat causes a rush of blood flow and nutrients to promote healing. I'm also going to put a heat pad on the top of my foot overnight and see if that helps. It's kind of a gamble - since inflammation is due to swollen tissue, and heat causes things to expand - it may actually result in a set back. I guess we'll see.

Day 41 - 11.75 miles easy - 12/17/11

Finally catching up on blog entries.  Before I wrote up yesterdays HR training zones entry, I had gone out and ran a mid-distance run at an easy pace.  After last weeks 11 miles at threshold, and recognizing I had not only taken a step back cardio-wise, but also physically (I had minor soreness for a day or two afterwards - previously an 11 mile run would have induced no such thing) - I figured it'd be a good idea to take a step back and get at least a couple weeks of easy runs in to build back up.  While my original plan had been to do shorter, more intense runs - the weather and crappy roads that led to me to that  plan have not come up yet, so other options become available.

If I was going to go easy, I wanted to add a little more distance than last week.  I wanted to keep it under 15 miles, though.  I ended up adding a segment to one of my 10 mile loops, hoping it'd add a few miles - and it did add distance, but not quite as much as I hoped.  Still, at 11.75, it turned out to be enough.

I started out at a nice pace and intensity - generally below 155 and somewhere between 8:45-9:00 min/miles.  However, after about 4-5 miles, I noticed that the HR was creeping up a bit, so I had to slow down a tad.  In retrospect, perhaps doing the back/bicep workout beforehand, plus only have a light breakfast, affected things more than I thought.  True, I haven't been running much in the past month - but the pace and corresponding HR were a little more out of whack than I'd suspect.  By the end of the run, I was having a hard time keeping the HR down, so I knew that I was pretty much done.

When I returned home and saw my average HR of 154, I was pleasantly surprised - I was concerned it'd be over 155.  Then, the secondary concern was whether 154 was low enough to be considered 'easy'.  After writing up yesterdays post and seeing the ranges for easy based on my performance, I saw that 138-157 fills that range of 65-79 %HR, so I just barely squeaked in.  However, I don't like cutting it that close. 

Later on that day, I started noticing a return of some right upper lateral calf soreness.  I felt it in the same spot after last weeks run (which was one indication that I needed to build up again), but it went away after a day or so.  Additionally, the top of my right foot started aching again.  I popped a few advil later that afternoon (after the ice bath), and this morning both are improved, though not totally gone.  I was hoping that with being off work this week, I'd be able to run a couple times - but those plans will have to be put on hold for the time being.  A yoga class or two should clear things up pretty quickly, and I hope to be able to get in a 5 miler or so during the middle of the week, and a 9-10 miler on the weekend.