So... Anyone who has talked to me for any length of time since October 2012 has likely had to hear me babble about eating Low-Carb/High-Fat... I'm going to try and talk about it less and write about it more so that my conversations can be less one-sided!
My interest setting up this blog is not to profess to be an expert - I am FAR from it. Even though I have been eating this way for almost a year and a half, I am still learning about it and I'm fascinated with the science behind different ways of eating and how it can effect performance.
I am always baffled by those who claim to have all of the answers - I sure don't. To this end I will post content and links that support and contradict. Of course I will concentrate on my experience with Low-Carb/High-Fat, but my hope and intention is that this can be a resource to explore further, not a one-sided endorsement of a narrow view.
So... brace yourselves... lots of posts coming your way...
Podcast on Fasting and Exercise...
http://www.bengreenfieldfitness.com/2014/02/combining-fasting-and-exercise/
This just got posted on Ben Greenfield Fitness today - I know what I will be listening to this morning...
This just got posted on Ben Greenfield Fitness today - I know what I will be listening to this morning...
Low-Carb/High-fat eating. What is it and who is it for?
There are a confusingly huge amount of labels out there that
describe different variations of a Low-Carb diet: Paleo, Atkins, Ketogenic,
& Optimized Fat Metabolism (OFM) all describe a low-carb plan. I don’t know enough about the specific nuances of any of them
to sort out which is which so I will just describe how I eat and you can call
it whatever you like.
I get the majority (75% or more) of my daily calories from
high-quality fat. I try to eat
around 100-120g of protein a day, which accounts for roughly 15% of calories. The remaining 10% come from carbs. Depending on how many calories I burn in a particular day,
the total grams of carbs typically ranges from 30-75. Please note that this is NOT a high protein plan – the main
calorie source is FAT.
I have been eating this way since October of 2012 and it
hasn’t been hard to stay the course.
Why do I do this? - There are a few reasons...
1. It is an effective way to lose or maintain weight without much discipline.
I weighed 140 pounds in June of 2012 and
had just finished the Kettle 100, at the time it was my 5th 100
miler since 2009 (I say this just to reflect that I wasn’t sedentary). I decided to tighten up my diet
and drop gluten and sugar.
That SUCKED! I really
had to be disciplined and I CRAVED sugar!
I did manage to shed 3 pounds, but I really had to work at it. In October of 2012 I went all in
on the Low-Carb/High-Fat plan (Thank you Zach Bitter!) and have been on it ever
since. The food is satisfying, I
don’t need to count calories, and I dropped down under 129 pounds. I recently had my body-fat tested
using a Dexa scan at the University of Connecticut and it showed 6.7% - Lean!
2.
It helps promote better recovery from running
– I feel better more quickly and I can handle more miles and more intensity.
There is a lot of science that indicates
that carb ingestion creates inflammation – not only in the heart, but all over
the body. Stands to reason that
any inflammation beyond the damage of running miles just adds to the load your
body is already dealing with.
3.
Runners that are fat-adapted need to take in
little or no calories when running below lactate threshold (65% of Max VO2)
–
A runner that is fat-adapted utilizes body
fat for energy instead of relying heavily on muscle glycogen when using aerobic
metabolism (More about this here). THIS IS ONLY WHEN
RUNNING AEROBICALLY! When you run
hard (think just about every race where you are breathing hard) your body will
start burning carbs. The
harder you run, the more carbs you burn. For a 100 miler, however, the pace is slow enough that
if you are careful, you are likely metabolizing energy aerobically most of the
time. The implication here is that
the amount of calories needed to ingest to complete the race for a fat-adapted
runner is less, since their body will rely more on stored body fat instead of burning
through limited muscle glycogen stores.
Any plan that allows me to eat less gels and goos gets a thumbs up for
me!
Based on just these three reasons, I would say that a lot of
runners could benefit from exploring a Low-Carb/High-Fat eating plan. No matter what race is your specialty,
everyone will be faster when body-fat is minimized and can work-out harder and
longer with reduced recovery time.
The benefit of eating less during a race is probably only going to apply
to ultra-marathoners though. The
longer the race and the slower the pace, the more this benefit comes into play. Limitations for elite athletes
that train and race at high-intensity will temper the benefits for racing.
This all being said, Low-Carb/High-Fat is not the
only plan you can have success with – Obviously there are TONS of athletes
thriving on traditional diets that are High-Carb/Low-Fat and it is not my goal to discredit or
discourage anyone from eating this way either. Read a lot, ask questions, and find what works for you.
Unchain my heart...
Anyone
who undertakes a Low-Carb/High-Fat eating plan will likely get a lot of
questions related to their pending early demise due to heart-attack. This is a valid question if you
undertake the plan half-heartedly and eat lots more fat and continue to eat a
high amount of carbs. If, however,
you follow the plan and stay within the food lists of healthy non-processed
food, your heart-health will definitely improve.
In
September of 2012, I had my cholesterol tested and it was 229 – A little high
for a total number, but my Triglycerides and HDL were good (as was the ratio of
HDL to Triglycerides) so my doctor was not concerned – this is how it broke
down:
HDL: 66
Triglycerides: 91
LDL: 145
The
number most people (and doctors) focus on is the total cholesterol level. This is a misleading number in that a
very high HDL (“good” cholesterol) number will make your overall number higher,
even though a higher HDL is supposedly a good thing.
Ideally
your Triglycerides are under 100 and the ratio of Triglycerides to HDL is
around 1. In fact, ratios give the
most accurate picture as it ignores the total numbers and focuses on the
relationships between the numbers (A great calculator and how to interpret the
ratios can be found here )
 |
| (click on the chart to see it larger) |
Most
studies are now zeroing in on triglycerides as the most direct predictor of heart disease. Triglycerides are produced when you ingest more calories than you can use immediately - This
happens ALL the time when you are eating carbs. Your body responds to the rush of easy calories by engaging
an insulin response and storing the energy in fat cells to be used later. There is a very direct relationship
between how many carbs you ingest and how high your triglyceride levels will
be.
I had my
cholesterol retested after 3 months on the low-carb/high-fat plan (started in
October 2012) – Total Cholesterol down to 217
HDL: 77
Triglycerides: 47
LDL: 130
HDL: 77
Triglycerides: 47
LDL: 130
 |
| (click on the chart to see it larger) |
I am surprised my LDL didn’t drop more (Although it had only been 3 months) – I need to go get it tested again as it has now been more than a year. Will get that done soon and update this post with the current state of my coronary affairs!
You eat WHAT?!
You eat WHAT?! - This is a question I get a lot when someone asks about this low-carb/high-fat eating plan. It's a fair question since many of the high-fat foods are things you add to a meal instead of being the main-course. There are some good Low-Carb/High-fat grocery lists for
dietary plans out there, but weaving the lists into meals can be a challenge at
first.
I typically cook breakfast at my house and it is a meal that is pretty easy. I have eggs every day and our family easily goes through a half-dozen a day at a minimum. Lunch and dinner are a bit trickier, but fortunately, my wife is pretty creative – For example, she will substitute spaghetti-squash or fried cabbage for pasta or get meat that has more fat like a shoulder roast. (We purchased an entire organic lamb this year and it was great to have such good quality meat!) Making sure you are getting additional good-quality fats in any meal can be a simple as including sour cream or cooking in butter.
I typically cook breakfast at my house and it is a meal that is pretty easy. I have eggs every day and our family easily goes through a half-dozen a day at a minimum. Lunch and dinner are a bit trickier, but fortunately, my wife is pretty creative – For example, she will substitute spaghetti-squash or fried cabbage for pasta or get meat that has more fat like a shoulder roast. (We purchased an entire organic lamb this year and it was great to have such good quality meat!) Making sure you are getting additional good-quality fats in any meal can be a simple as including sour cream or cooking in butter.
My typical meals look like this:
Go-To Breakfast: - 3-4 Eggs & Coffee with heavy cream –
(Sometimes I add cheese to my eggs or have either bacon, sausage)
Go-To Lunch: Steam
in the bag spinach or cauliflower/broccoli mix, cheese, chicken, and heavy
cream (or leftovers from last night’s dnner!)
Go-To Dinner:
Cabbage fried in bacon lard, with ground-lamb or ground beef, sour cream, and a salad with
greens, olive oil and balsamic-vinegar.
Another dinner we like is baked chicken thighs with olives and
cauliflower. Bake the olives right
in the pan with the chicken – and the cauliflower can be mashed up with the
chicken drippings – WAY tastier than potatoes!
There are low-carb/high-fat recipes for nearly every typical meal you could eat, so you don't have to feel like you are giving up all of your favorites. A great example is almond-flour pancakes (I also substitute heavy cream for milk in that recipe). Making a version that is higher in good-quality fat usually makes it better and tastier!
Optimized Fat Metabolism
Endurance Planet posted a recent podcast with Zach Bitter regarding Optimized Fat Metabolism ... Good Stuff!
http://www.enduranceplanet.com/zach-bitter-on-nutrition-benefits-of-optimized-fat-metabolism-for-endurance-athletes-incorporating-speedwork-in-ultra-training-his-2014-goals-and-more/
http://www.enduranceplanet.com/zach-bitter-on-nutrition-benefits-of-optimized-fat-metabolism-for-endurance-athletes-incorporating-speedwork-in-ultra-training-his-2014-goals-and-more/
The impact of fueling for a race when Fat-Adapted...
I am fully geeking out on numbers as I start thinking about a fueling plan for the Mad City 100k coming up on April 12th. This is some seriously obsessive number crunching, so proceed with caution if you aren’t a fan…
Armed with some of my preliminary results from the UConn FASTER study and a little extra research, I have a plan in place for how many calories I think I will need. I thought I would share my thought process, as it illustrates a distinct advantage for competitors who are fat adapted.
The 100k distance on the road is still a speedy race and the more you push yourself past the lactate threshold, the more stress it puts on your system and the more challenging fueling becomes. Part of the advantage of being fat-adapted is that I should (theoretically) be able to do the race and ingest fewer carbs and rely more heavily on stored body fat. This is important in that needing to take in less calories will also leave more blood volume available for muscles instead of diverting some blood volume for digestion - keeping my stomach from rebelling.
During the FASTER study at UConn they were able to test the amount by grams per minute of fat and carbs that each participant was burning at various VO2 max levels. 65% of max VO2 is the level associated with lactate threshold – the tipping point level at which metabolism starts to become more anaerobic and lactate begins to build in the muscles. This would be a pace that is comfortable; conversation pace. Elite marathoners (I am not one!) race near 85% of max VO2. I doubt I will be running that close to my ceiling during the 100k, but I will assume 85% just to be safe.
To start the FASTER study, they did a VO2 max test to find the max of each participant and used the data to establish what 65% of max VO2 would be for each individual. In this way they could ensure that each participant would be operating at similar efforts even though the actual pace might vary.
It is a fact that the level of carbs metabolized gets greater the more anaerobic the effort is and this was reinforced during the treadmill test at the FASTER study. This disparity was far less pronounced with fat adapted athletes who had trained their bodies to rely on primarily metabolizing fat at lower exercise intensities. Conversely, an athlete who eats a traditional high-carb diet begins even low-level efforts by burning mostly carbs in the form of muscle glycogen.
My results were typical of the other high-fat/low carb trained participants. For example, at 65% of max VO2 on the treadmill, I was running 7:50 mile pace and at this level I was burning 1.24 grams of fat per minute and zero grams of carbs. As the intensity rose and VO2 levels got to 75%, I was burning 1.07grams/minute of fat and .95grams/minute of carbs. (Keep in mind that a gram of fat yields 9 calories and a gram of carb is 4 calories, so even at this level fat is supplying me with 70% of my metabolized energy needs). At 85%, I was burning 1.04g/fat per minute and 1.49g of carbs per minute. This amounts to 1.04 x 9cal (9.36 calories from fat per minute) and 1.49 x 4cal (5.96 calories of carbs per minute). At this level, 61% of my calories were coming from fat metabolism.
If we can assume 98 calories are burned per mile,
(http://www.runnersworld.com/tools/calories-burned-calculator)
I will need 98 x 62 = 6,076 calories during the Mad City 100k race.
61% of the 6,076 calories (3,706 calories) should come from stored body fat. This leaves 2,370 calories that will depend on carbs. These carbs can come from glycogen stored in muscles and from carbs ingested during the race. A typical male would be able to store 1,800-2000 calories in skeletal muscle in the form of glycogen. I will assume that as a smaller, 130lb. male, I can store approximately 1300 calories.
If my body has around 1300 calories of muscle glycogen on board, then I technically only need to ingest: 2,370 – 1,300 = 1,070 calories of carbs during the race.
Since I normally run in a fasted state, I would like to wait until after 20k to start taking in calories just to let my body and stomach settle a bit. If I take in 150 calories between each 10k loop starting after loop 2, I would get 8 x 150 = 1200 calories. This should average out to taking in about 200 calories per hour.
Lets think about the case of a High-Carb trained athlete and how the numbers being reversed would effect fueling:
Again: 98calories x 62miles = 6,076 calories needed.
If 61% now came from carbs (instead of fat), 3,706 calories of carbs would be needed during the race. With 1300 calories of stored muscle glycogen, that leaves 2406 calories of carbs to ingest during the race.
If I took these carbs between each loop (9 times instead of the 8 times above) that would be 276 calories of carbs per loop or 356 calories need to ingest per hour.
This is nearly 4 gels an hour, the edge of what most people’s stomach can handle, especially when trying to run hard during a road 100k. No way could my stomach take that. If the stomach does rebel, and one can’t take in enough calories, you would be forced to rely on metabolizing fat only. For an athlete who doesn’t train in fasted state and doesn’t primarily rely on metabolizing fat, their pace must slow to a lower VO2 max threshold – likely below 65%. This means a big slow down late in the race as ingestion of carbs fails to keep up with need. This is what I am hoping to avoid.
The further implication is that for a race of less intensity, say a 100 miler, a fat-adapted athlete ought to be able to rely almost entirely on stored fat for fuel as long as they stay under lactate threshold - 65% of max VO2 (In theory anyway!!). On April 12th I will see what happens when theories and reality collide! Hope it goes well…
(I’m sure I have messed up some of these numbers, so feel free to point out any mistakes!)
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