Blog Archives9/1/07 Replacing what you burn
Having stated those five assertions as axioms, let's look at some postulates that can be
formed. (Incidentally, my construction of arguments is very much based on my
experience as a mathematics professor where you start with premise and work towards
conclusions - if you prefer the legal approach of stating the conclusions first and then
working back to the evidence, you could always wait a week and read my entries in
reverse.)
I need to beg one point: optimal weight trumps optimal fitness. I don't have much other
than personal experience and a few anecdotes to support this, but I firmly believe it. I
remember reading an interview with Eddy Merckx's doctor who stated that, for all his
greatness, Merckx was in a constant struggle to keep his weight down. When he'd be
eating 7 to 8 thousand Kcal/day, he'd be just a bit too heavy and it would affect his
results. If he could stick with 5-6 thousand, he'd be at his best.
Shortly after reading that, I decided to put it to the test and start paying a bit more
attention to how much I ate. My weight dropped very quickly from 178 to 172 and, much
to my delight, I was promptly upgraded to
USCF's vaunted "Cat-2" status, which is generally considered the big stepping stone
towards pro cycling. I wouldn't have guessed that 6 pounds would make such a
difference, but it did. Even now, in my purely amateur pursuits, I've found that just a few
pounds have a significant impact on performance.
The reason this point is important is that nearly all these studies on glycogen replacement
focus on maximizing the rate of resynthesis. The general consensus is that you can
completely replenish glycogen stores in 20-26 hours by eating 500-600g of carbs
following exercise. Ideally, this is doled out in doses of roughly .7g carbs/1Kg body
weight every 2 hours. That's great, but it's also 3000Kc of food in a day, and that's just
carbs. Throw in a bit of fat and protein and you're closer to 5,000. That's fine if you're
really burning that much (as most elite athletes do) but for us amateurs that's a one way
ticket to fat city.
Here's the question that never seems to get asked: why is it so important to replenish
carbs? Obviously, you want to have carb stores maxed for a competition effort,
particularly one in the 2-3 hour range. But, so what if you head out for your normal
8-mile maintenance run slightly depleted? The chance of bonking on a workout like that is
somewhere between zero and none.
I think this is a classic case of amateurs wanting to apply only the fun part of the "pro"
formula to their training. The diet of an elite athlete makes sense for an elite athlete. It
makes very little sense for anybody else. If you're going to slam 5,000Kc/day, you'd
better get out there and burn it. I can tell you from experience that that is no small thing.
Consider quitting your day job if you want to pull it off.
9/2/07 Why Atkins works
OK, I'm going to mention the name that brings nearly universal derision amongst the
athletic crowd: Atkins. Before you completely write me off as a nut, have you actually
read his book? What Dr. Atkins prescribes and what is typically practiced are two very
different things.
In a nutshell, the idea for the maintenance phase (the only phase that's of much interest
for an endurance athlete), is that you eat just enough carbs to cover your output, and
no more. Other than that, you have a pretty free hand, although he does warn against
eating too much red meat or other fatty foods (a warning often ignored by those
practicing the diet).
In light of the first axiom (eat what you burn), I'm not sure why that is regarded as so
radical. If you are burning 500g of carbs a day, go ahead and eat that many. But how
many people really do that? 500g of carbs is over 2000Kc. Depending on intensity that's
somewhere between 2 and 4 hours of effort. However, not all of that will come from
carbs. In fact, given that it's a long effort, most will come from fat. To actually burn
2000Kc of carbs, you're probably looking at 5 to 7 hours of effort.
That's not to say that you'll gain weight if you eat 2,000Kc of carbs and burn 2,000Kc of
mixed carbs and fat. You won't. The problem is that you'll probably eat a lot more than
that because a 4-hour workout leaves you pretty hungry. That's the "secret" to Atkins: it
addresses the hunger issue rather than the supply issue. Eat enough carbs to cover your
needs and then eat protein and fat to cover your hunger. You eat less and maintain the
weight you want. It ain't rocket science.
9/3/07 Just enough
Maybe you're the type who can step back and objectively say, "I burned 1,000Kc
working out and another 2,000Kc in basal metabolism today, so I'll just eat 3,000Kc
today." Rarer still, maybe you can actually do it. If so, you don't need my advice; you
should be at optimal weight already.
Now, let's talk about the rest of us. Working out makes you hungry. The human body
does not particularly like being starved down to 2-3% body fat. Most people need some
help to maintain such a level. That's where monitoring carb intake can pay big dividends.
If controlling appetite is an issue for you, read on.
Fat is a natural appetite suppressant. By limiting carb intake to just what's needed, you
free up the rest of your intake for eating stuff that leaves you less hungry. No, I haven't
forgotten about protein - you need some of that, too - but (axiom 3) not that much. It's
quite possible to maintain a good weight on a diet where nearly 50% of the calories come
from fat. Eating that much fat will leave you much less hungry and thus make it that
much easier to maintain optimal weight.
Some care needs to be exercised that the fat sources are not detrimental in other ways. In
particular, red meat presents some real problems, not the least of which being excessive
amounts of saturated fat. However, nuts, fish, olive oil, and the like are great sources of
satiety without clogging your arteries. In fact, the most current research indicates that
most people are suffering from not enough of such fats rather than too much.
9/5/07 When to eat
Aside from quibbling over the exact amount of fat and carbs in the diet, nothing I've
stated so far in this series is particularly controversial. Here's where I start to diverge
significantly from conventional wisdom: I prefer to train while partially depleted. I've
always done this, even back in my 20's when I was eating carbs by the bushel. My
M.O. has always been to train first and then eat to replenish.
Now, I'll concede that this appears to be a personal constitution thing. Some people
simply can't train on an empty stomach. My problem has generally been the opposite: I
have difficulties if I've got a bunch of food in my system. However, if you can do it,
there are some real benefits to be had.
First and foremost, your body will adjust the ratio of fat to carbs burned during exercise.
It will do this without a detrimental effect on performance. If you consistently
train when your liver glycogen levels are just a bit low (not depleted, but not maxed out
either), your body simply gets better at burning fat. It will still burn as much glycogen as
needed to maintain the desired output level, but it won't burn a lot more than that.
Why is that so important? Well, it's not if you are really conscientious about keeping
your liver glycogen levels high. But, suppose you have a 5AM start for an adventure race
and the first discipline is a 2-hour trek on hilly trails that ends with a ropes section. If you
don't want to be stuck in a long line at the ropes, you're going to have to push it on the
trek. Your body doesn't know there are 22 more hours of racing to go, it just knows that right
now you're asking it to go hard, so it will blast through glycogen at a rate
more common to a 4-hour race. It's great that you didn't have to
wait for the ropes, but you've burned up half your glycogen stores in the first
10% of the race.
You could fix this by getting up a 3AM and eating a good sized breakfast, but now you're
racing on very little sleep. You could eat right before the start, but that might upset your
stomach. You could slam carbs during the run, but that can lead to some nasty digestive
problems later in the race as well.
On the other hand, if getting out of bed and running 20 miles without eating is something
you do a couple times a month, your body will be used to providing the bulk of the
energy from fat, even at higher outputs. You will get to the ropes with your glycogen levels lowered, but not by much.
Unless you're going anaerobic on the trek (not advisable in a long race for many reasons),
you can go just as fast burning fat and you can get your glycogen levels back
quickly by eating at your normal rate during the trek and a bit extra while watching your
teammates tackle the ropes. Don't forget to shout encouragement between bites.
Outside of competition, by training your body to rely more on fat, you increase your
ability to maintain optimal weight. If you need fewer carbs, you can eat fewer carbs,
which means you can eat more fat, which controls your appetite and helps you keep your
total caloric intake where it should be.
Training your body to run primarily off fat also makes your training more efficient. It's a
well known maxim that you need to train at least 2 hours to force adaptations that improve
endurance. This is because it takes a couple hours of exercise to deplete the glycogen levels
to where fat burning is increased. However, if you start the workout with less glycogen in
your system, you'll get to that point quicker and more of the workout will contribute to
improving endurance.
Finally, by eating after working out, you are targeting your replenishment window.
Recall that one downside of restricting carbs is that you can't always get your liver
glycogen levels fully restored before the next workout. This will still be true, but
less so if you time your carb intake to coincide with the time when your body does the
fastest replenishment. This is during the 2 hours immediately following exercise. Try to
get in .7g carbs/Kg body weight during this period if possible.
Incidentally, it's generally agreed that simple sugars are processed faster than complex
carbs during this window, so if you have a sweet tooth, here's your chance to scarf down
something yummy and help your training at the same time. Don't go overboard, though.
Fifty grams of carbs isn't as much as you might think - 2 cookies from
Subway will do it.
9/6/07 The plan
To review: we're looking for a diet that matches intake with output, adequately
replenishes carbs, and controls appetite. Here's what I do.
First, the carb calculation. I seem to get by just fine on 100g of carbs a day, plus another
50g for each hour of exercise. I'm not too strict about that, some days I'll be considerably
over or under. However, if I average out to that, I have no trouble completing workouts,
including some that are both long and hard.
To maximize replenishment, I eat the 50g doses every 2-hours after the exercise. For
example, if I run for two hours, I'll eat 50g right at the end of the run and another 50g a
couple hours later. The 100g base gets spread out however it best fits in.
Next is total caloric intake. My base here seems to be around 2,000Kc/day plus whatever
I burn exercising. Again, I don't try to match this exactly each day, but if it averages out
over a week, I'm usually the same weight at the end as when I started.
Other than that, I pay some attention to cholesterol, not so much because I'm worried
about it, but it's generally a good indicator of whether the type of fats you're eating are
good or bad. I try to keep the total to under 200mg/day, but I'm not very strict about that
at all.
There are some practical considerations that I'll get into later, but it's a pretty simple plan
and it's worked very well for me.
9/9/07 Practical considerations
Being an aerobic athlete on a restricted carb diet does require some modifications to the
normal training routine. Again note I didn't say low-carb; you have to eat enough carbs,
you just don't eat more than enough.
The biggest adjustment I've had to make is lengthening my warm-up for workouts. I
always was one for a long warm-up before races but, I would typically get hammering
pretty early on in a workout. I now find that I need at least 20 minutes before I can really
hit the gas. This is no surprise, since 20 minutes is about how long it takes for you body
to ramp up fat burning. If you do a lot of 30-minute workouts, this diet will kill your
training. Almost all my sessions are significantly longer than that, so it's really no big
deal for me. If I'm out for less than an hour, it's an generally an easy maintenance
workout, not something that requires efforts near VO2Max.
Because a long workout will leave me very depleted and I won't be slamming carbs to
get levels back, I have to schedule a pretty easy day after any long day. Combined with a
respect for the 36-48 hour recovery window, that means a long workout takes a full 2
days out of my training schedule. I should note that I'm only talking about genuinely long
workouts here - 4 hours or more. On this regime, a 2-hour workout is no big deal because
your body is getting so much of its energy from fat. Therefore, I only have to schedule
around this 2-3 times a month.
My eating schedule has also needed some adjustment. Because it's important to
maximize the replenishment of what carbs I do eat, I have to be more conscious of
getting around 50g of carbs every 2 hours after a workout until I'm up to my limit. The
only time that's a problem is if I finish a long-ish workout late in the evening. In those
cases, I'm back to having to schedule some light work the following day.
None of this has been much of an inconvenience to me, but it might bug some folks.
There are, however, some very real concerns that anybody considering this approach
should take into account. I'll get into those tomorrow.
9/11/07 Caveat emptor
I said at the outset of this series that my practices are based on what I've read and what
I've experienced. I've shared the upside. Now, here's the other side of the story.
What I've read. The long term effects of a low-carb diet are not well understood. There is
concern in the medical community that such diets could lead to problems with kidneys,
liver, and blood sugar levels (hypoglycemia). Also, if care is not taken to avoid the wrong
types of fat, there is an elevated risk of heart disease.
What I've experienced. I recently had my gall bladder removed after routine tests
detected liver enzyme levels that were off the charts. The gall bladder was full of stones.
The physician felt that my very low body fat was also a contributing factor. A year ago I
tested borderline high for cholesterol for the first time in my life. This was due to very
high levels of "good" cholesterol, but still something to watch. I have since corrected this
by being a bit more careful with my saturated fat intake. Finally, for the past year or so,
my blood sugar levels have been hypoglycemic, albeit just barely. That doesn't seem to
bother me any, although it could help explain why I need such a long warmup.
None of the physicians I've consulted with are willing to draw direct causation between
my low carb intake and these other issues, but they don't deny that it could be a factor.
They also agree that the more careful application of the diet over the last six months is
less likely to cause problems.
When I started restricting carbs in 2003, I weighed 205 pounds and had not turned in any
significant results since retiring from cycling 10 years earlier. Since then, I've dropped to
under 170, set a significant PR at marathon distance, placed in the top 5 at USARA
nationals, and won an age-group championship in orienteering. Hell, yes, I'd do it all
again. But, I'd be a bit more careful about it. Most of my internal organs are not
expendable.
9/12/07 Frosty
Just two weeks after struggling to keep my hydration up while training in 100-degree
weather, it was so cold this morning that I regretted not wearing a long-sleeved jersey and
tights for the ride into work. I can't say I'm at all unhappy about this development
(temporary as it is - tomorrow is predicted to be back in the 80's), but it sure took me by
surprise. I got into work about 10% quicker than usual because I was spinning
fast to generate some body heat.
9/14/07 Back on track
I ran intervals on the track yesterday. I've done almost no track work since the marathon
because I've been doing my quality work in the terrain. I think that's preferable, but
there's something to be said for the objectivity of the track. Now that I'm in buildup
rather than base, I'll be doing more quality work. I'll try to get one of the sessions on the
track each week.
9/15/07 Tour of Missouri
Very busy day today and no time to write, but I'll just quickly say that the centerpiece of
the day was watching the Tour of Missouri roll
through. David, Doug, Jeff, and I rode out to Augusta where we met Vicky, Carrie, and
Ken DeBeer at a winery. Then we went to the King of the Mountain climb out of Augusta
to cheer them on. Strangely, it's the first time I've ever watched a road bike race that I
wasn't also participating in. It was a great time. Thanks to Jim Stroup for the photo.
9/16/07 Kirkwood Night-O
SLOC held its annual Night-O at Kirkwood yesterday. It was fun, despite being a bit
toasted from all our riding during the day to watch the bike race. That's less of a problem
in a night event because you generally have to move a bit slower to stay in contact with
the map. That said, there are few things more fun than really blasting a night event. I ran
reasonably well tonight, but in other years I've really pushed hard in this one. That's
exciting because mistakes are really expensive at night, so you know you're taking a risk.
9/18/07 Burrs
I more than a few minutes this evening pulling burrs out of the socks I wore in the woods
yesterday. It's just one of those things you do around here in the fall if you want to go off
trail. I've heard many people gripe about this fact. I'm not sure why that is so. I never
hear people complaining about having to lube their chain after mountain biking or
recharge their batteries after a night workout (although some are negligent about doing
such things). It's just part of maintenance and certainly no excuse for not getting out there
and training.
9/20/07 Last sprint
We held the last of the Carol's Team Third Thursday Sprints for this year today at West
Tyson. We had a decent turnout despite the fact that many of the regulars couldn't make
it. Nice to see new faces. I'll have a meet report with the map soon. In the mean time the
highlights are that David Frei scorched it in 12:16 and it was getting really dark
by the time everybody was in. Fun times had by all.
Next month we start the Adventure Runs. These are a cross between trail running and
orienteering. Everybody starts at once and the course is designed so that the preferred
route is trail (through you can cut corners through the woods if you want to). It will
definitely be dark, so bring a light. Details will be posted soon.
9/21/07 Results posted
Results from yesterday's sprint as well as information on the adventure runs is posted on
the
Third Thursday page.
9/22/07 Tactics
Orienteering and adventure racing generally don't call for much in the way of tactics.
Getting through the course as quickly as possible is almost always your best plan,
regardless of what your opponents are up to. Coming from a bike racing background, I
miss tactical races. Today, I got a surprise opportunity to engage in a tactical race.
The New Town Blast 5K is a small running race held in St. Charles. At last year's
inaugural running, I finished third, which is a lot closer to the front than I usually am. I
figured the field would be a bit stronger this year and my fitness is still a bit off from the
surgery, so a podium spot was unlikely. So, I turned my focus to the 40+ class. I wasn't
sure where my fitness was, so I decided I'd just match the top 40+ runner(s) and see what
happened.
What happened was a really fun race, and one that resulted in a decent time as well. In
the first mile, five runners jumped out to a quick pace followed by a larger group that
included the 40+ leaders. I quipped that this was the "old man" pack. I took up position
on Dennis Guyon's shoulder. He usually runs mid-18's for 5K, so I figured I wasn't
going too far out on a limb. The pace felt stiff, but doable.
At half a mile, Horacio Maluf surged ahead and got a gap of about 20m. I didn't want to
go too deep just yet and stayed with Dennis. Horacio hit 1 mile at 5:55, three seconds
ahead of Dennis and I. We were about to turn into the wind which presented me with my
first important decision: stay with Dennis, or get up to Horacio. I decided to surge across
the gap and got on Horacio's shoulder shortly after making the turn. At 1.5 miles we had
the wind at our backs again and I was feeling pretty good about the pace. I decided to
launch another surge, hoping to catch one of the young-uns before we turned back into
the wind. I succeeded in getting across the gap (going through two miles at 11:59), but
the fifth-placed runner, Michael Duvall was fading so I had to go by and take the last
headwind section alone or risk getting caught by Dennis or Horacio.
Having fully committed to the move, I hit the headwind section with what little reserves I
had left. Mercifully, the last half mile was downwind again, and I was able to finish with
a respectable 18:32 for fifth place overall and the Master's win. Given the rather paltry
speed training I've done lately, I wasn't at all displeased with the time, but what really
made the race fun was the head-to-head battle. While it's a good practice to enter and get
trounced in a "big" race now and then so you don't get thinking too much of yourself,
trying to win one of these little local affairs is certainly more entertaining than just
checking your pace every time you pass a mile marker.
9/23/07 Night speed
A week ago I wrote that you generally move slower at night to stay in contact with the
map. That's both true and false. It's true that most people move slower at night so they
can stay in contact with the map. What's false is the notion that staying in contact at night
requires you to go slower than staying in contact during the day. It doesn't. The
difference is that all the little sections where you run with loose or no contact during the
day tend not to bite you as hard as at night because relocation is easier, particularly if you
have only been out of contact for 100m or so.
One of the reasons I like running my day speed at night is because it becomes much more
obvious when you are outrunning your map contact. During the day you might recognize
that you're starting to lose contact, but push on figuring you'll see something you expect
pretty soon. Usually you'll be right. You may not even realize that you were out of
contact for a bit. At night, once you've lost contact there's a pretty good chance you're
screwed.
Artificially raising the penalty for error is one of the ways to speed up the programming
of a neural net (a type of computer system that operates on the same principles as the
brain). The technique seems to work well training an actual human brain as well. I find
that I'm much more conscious about staying in contact, even if it means slowing down
just a bit, after I've done a bunch of night training at speed.
9/24/07 Hater
Shortly after putting on Team Trials last year, I got an email from Bob Lux asking
something about mapping. I don't remember the question. I didn't respond. No good
reason, certainly nothing personal (if I've ever even met Bob, I don't recall the instance),
I simply didn't feel like working on somebody else's issues just then. Anyway, for some
reason, not getting a response to an unsolicited email made Bob mad, mad, mad.
Lately, Bob's been trolling my training log on Attackpoint looking for opportunities to
make hateful comments. That's fine - it's a public forum and if he wants to represent
himself that way, he's free to do so. It does make me wonder, though, why the online
community is so prone to these vindictive attacks. I mean, check out
his latest.
As far as I can tell, the two offenses I'm indicted on are 1) arrogance and 2) not returning
his email. Well, both of those accusations are true enough, but how many enemies must
you have if that's all it takes to get on your bad side? Only someone clinically psychotic
would get so worked up over such things in a face to face meeting but somehow the web
is a "safe" place to let rip.
Ten years ago, I would have happily engaged in a flame war with Bob. An easier target
would be hard to find. He's defending an absurd position, making sweeping generalizations,
and contradicting himself. Most fatally, he's clearly emotionally wrapped up in
the argument. Arguing passionately can be a useful rhetorical tactic, but letting
passion drive the argument is never a good idea. Once you know which buttons to push,
you merely need to push them to convert a Nobel lauriate into a stupid statement generator.
But, while I am happy to trade barbs with someone like Peter Gagarin who
gets the joke and is quick to come back with something
witty (note the reference to packing a 9mm in conclusion 2), stirring up genuine hatred
(see, "my hands are shaking on the keyboard") is a pastime that lost its appeal when
Carol got sick. Life is too short to waste hating people (or worrying about people who
hate you).
9/25/07 Gear
I was packing up for my trip down to Van Buren to vet the Berryman course this evening.
It struck me that it's been a while since I've done a race or workout of this length (I'm
expecting to be out there for 10 hours or so). While I certainly won't carry a full AR Gear
list with me, I do carry a lot more for something like this than I would for a "normal"
long workout of 3-4 hours.
Here's what I consider to be a minimal gear list for a 10-hour trek solo in the woods:
- 100oz bladder
- Water purification tablets
- 1500 calories of food
- 20 electrolyte tablets
- 3" Ace bandage
- Ibuprofen
- Change of socks
- Cell phone (it generally won't work, but it doesn't hurt to try)
- Whistle
- Map case
- Light and backup light (I plan on doing all this during the day, but you can't be too
safe on this count - getting stuck out after dark with a failed light can become life
threatening real fast.)
- Compass and backup compass
And, most importantly, Jason will know exactly where I plan to go and when I plan on finishing.
Always have someone check up on you.
9/29/07 Ass Kicker
Jason swore me to secrecy, but now that the
Berryman is underway, I think I can talk about the
course without giving anything away. One thing is for sure, this year's edition will live
up to the tag line: "A real ass kicker."
It's a great course. The first trekking section is technical (at least by AR standards) and
augmented by the fact that it's in the dark. Then there's a ton of mountain biking -
something like 40 miles - almost all of it on single track. Another trekking section is not
technical, but has two really good route choice legs (and we're talking 10-15 minute
consequences, here). Then you paddle until dark and go right back into technical nav. Get
that done and hammer the bike and maybe you're in before dawn. It's good stuff and I'll
have more to write over the next few days.
I enjoyed vetting the course. If it was an orienteering meet, I might have quibbled over
some of the placements, but on such rough maps, I think everything was within an
acceptable margin of error. Jason has been putting on 5-10 races a year for the past two
years and his course setting shows it. He's really proved himself worthy of putting on the
National Championships this November.
9/30/07 Camping
Yaya and I went "camping" last night. Well, OK, we put up the tent in the back yard. The
great thing about 4-year-olds is that such lame gestures are greeted with enthusiasm that
literally surpasses words. She responded to the suggestion by leaping around the living
room for a few minutes.
I'm happy that she likes sleeping in the tent for two reasons: it's just nice to have her
liking the outdoors and it opens the possibility of taking her to an extended event like the
1000-day. Now, if I could just learn to like sleeping in the tent...
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