Exercise On Low Carb
You can only lose weight on low carb diets, say low carb diet fans. And go on to tell us that athletic performance from running marathons to lifting weights is just as good when you say no to carbohydrates.
Scientific Evidence
But already in 1939 two Danish scientists put people on a low, moderate or high carbohydrate diet and after a week assessed their endurance to exhaustion on a stationary bike. The people on the low carb diet lasted 81 minutes. Those on a high carb diet were able to ride for 206 minutes (Christensen EH, Hansen O, Zur Methodik der respiratorischen Quotient-Bestimmungen in Ruhe und bei Arbeit. Skand Arch Physiol 1939, 81:137-71).
And in the last 71 years the pile of scientific evidence for this effect has accumulated; the latest study I am aware of that looked into it is from 2006, where scientists from New Zealand put cyclists on either a high carb or high protein diet with no difference in calories consumed. They as well came to the conclusion that a high protein diet has a detrimental effect on exercise performance.
Anecdotal Evidence
Yet we get tons of what pretty much amounts to “now explain that away!” defenses for fitness on low carb, where someone knows someone who or even himself went low carb and experienced astonishing athletic success.
What we don’t know is if that account is truthful or how the person would have performed with an adequate amount of carbohydrates. Which is why scientific research is always conducted in an environment where all factors that can come into play are accounted for.
Cognitive Abilities?
Even when low carb fans do look at the mountain of scientific research that clearly indicates a low carb nutrition is hindering exercise performance, a remarkable capability of selective cognitivity comes into play, that effectively blinds out everything that simply cannot and shouldn’t allowed to be.
An Australian study had cyclists on a low carb diet with a high carb day right before a race. They found no significant impact on fat adaption, meaning that stamina didn’t improve by the body previously having used more fat for fuel and then doing a carb-loading.
But one blog author titles his piece “Low-carb diet gives endurance athletes more stamina” and tells us:
The authors [of the study] therefore conclude that a low-carb diet is not of interest to endurance athletes. “A high-fat, low-carb diet, followed by 1 day of carb restoration, increased fat oxidation during prolonged exercise, yet, this study failed to detect a statistically significant benefit to performance”, they write. We on the other hand, not hindered by a knowledge overload, draw the opposite conclusion.
A 2004 paper (PDF) tries to make a point for moderate low carb diets, but it too has to conclude that “performance is limited by the low muscle glycogen levels induced by a ketogenic diet, and this would strongly discourage its use under most conditions of competitive athletics”. On a popular low carb forum however, we find mention of this paper in a completely different light:
I have no doubt, that you can run marathons on a low carb diet. I’ve been on a low carb diet for 1 1/2 year and I don’t think, that my endurance has decreased.
There’s also a very good scientific paper about ketogenic diets and physical performance:
http://www.nutritionandmetabolism.com/content/1/1/2
The problem is, most people won’t believe in the superiority of low carb diets, as long as all professional athlets follow a high carb diet.
It’s really strange, that nobody can tell just a single name of a professional athlet following a low carb diet. As far as I know, Lance Armstrong was not on a low carb diet, he was probably just better doped than the others 🙂
The discussion then continues and puts the blame on “carb-indoctrinated” trainers that just can’t acknowledge that a low carb diet is at least as good for professional athletes.
No Gravity
Draw your own conclusions, maybe experiment a bit and see what allows you to perform better. But the dogmatic disregard and abuse of scientific research displayed by the people above is akin to denying that gravity exists, because one day an apple might come along that just might fall upwards.
Picture courtesy of Richard Masoner.
22 Comments
Maybe low-carb diets increase the likelihood that you will exercise “selective cognitivity” in favor of low-carb diets 🙂 😀
Perhaps we should look into the neurological processes that may go hand in hand with it 😉
nice pic
This is why I think it’s paramount for any developed country to teach all their citizens how to read the abstract of a study, critical thinking etc.
I mean, it’s not like the people you cited don’t have a high school diploma? Some of them might have gone to university-level, yet they come to such false conclusions?
Alas, given how much we tolerate the “I have made up my mind, and I’m sticking to it, no matter what the evidence says”-attitude, I’m not surprised we’ve got so many people advocating this type of thing.
It is surprising how stubborn *very* educated people can become once they have made up their minds 😉
“I have no doubt, (WTF IS A COMMA DOING HERE?) that you can run marathons on a low carb diet. I’ve been on a low carb diet for 1 1/2 year (NEED COMMA HERE) and I don’t think, (NO COMMA ARSCHLOCH) that my endurance has decreased.
There’s also a very good scientific paper about ketogenic diets and physical performance:
http://www.nutritionandmetabolism.com/content/1/1/2
The problem is,(DUMMKOPF) most people won’t believe in the superiority of low carb diets, as long as all professional athlets follow a high carb diet.
It’s really strange, (VERDAMMT NOCH MAL) that…”
You shouldn’t take advice from someone who doesn’t understand the most basic rules of English grammar.
But to be fair, that user may be German in which case a comma does indeed follow “that.”
For instance, “Da ist das Mädchen, das gestern sehr freundlich war or Ich glaube, dass ich richtig war.”
Just sounds like another ignorant, illiterate American to me.
Don’t be so hard on the Americans, because I too think that user was German 😉
precede that*
Primitive humans were on a low carb diet. But they had much more endurance than us ,even if we are in a 100% carb only diet.
Now isn’t this also “scientific” ?
No.
Double no.
Funny, the strength training program I’m on right now endorses a low carb diet for most of the week with a fast day (to lower inflammation and control insulin levels) and a cheat day (to build up the glycogen stores again). I’m taking BCAAs during workouts on strength training days.
I have noticed that I tire very quickly during a workout after a few days of low carb, but can power on after a cheat day… I wouldn’t try endurance exercise at all on low carbs!! I have trimmed down a lot though, and have put on some muscle too which is all good… 🙂
Quite right, Deb. Carbs simply are the No. 1 thing that makes muscles go.
Seems to me that low carb probably works simply because if you’re willing to keep the “low carb” stipulation, it’s probably harder to eat enough food to maintain your body weight. This is all conjecture though.
My brother went low carb for two weeks and dropped ten pounds. He jogged about a mile a day, but wouldn’t really eat dinner that my mom made. He probably lost weight simply because he wasn’t eating as much. After quitting that diet, he lost over 65 pounds keeping his regular diet but simply cutting calories, and doing some home weightlifting and jogging.
I think you are on to something here; many of those diets that restrict a certain macronutrient lead to weight loss not because x or y is not eaten, but because it leads the people doing those diets to (maybe unknowingly) control their calorie consumption for the first time ever.
High carb diet. What does that mean? It can mean anything right? Carbs include whole wheat breads and pasta as well as high fiber fruits and vegetables. Low carb diet works because I have done it, but I have also lost a substantial amount of weight by eating healthy carbs with empty carbs and protein. Sometimes eating too much protein can make you have high cholesterol levels especially if your parents have heart cholesterol themselves. It is all about calorie consumption and eating a balanced diet. I just think that most Americans are just not as active as they should be and I think I had read somewhere a while back that we are one OF the fattest countries in the world.
Yes, basically it always comes down to calories in vs. calories out. No matter if low carb, high carb or whatever else – do what you are most comfortable with.
And according to what I read, we Germans are the fattest Europeans 🙂
Has anybody read “Why We Get Fat; and What To Do About It” by Gary Taubes? I’ve been doing calories in vs.calories out for two years with little result. I track EVERYTHING that goes into my mouth. I run everyday, somtimes up to 5 miles. No luck. Taubes says Carbs are to blame and sites studies that many Health and Fitness uthorites seem to have ignored. He says things are a little bit more complicated by simple math that the law of thermodynamics (calories in vs calories out) is a law of PHYSICS applied to a study of biology.
He also says inactivity and overeating are symptoms of overweight, not the cause. He likens it to a room that has too many people in it. If you ask “why are there so many people in the room?” and you get told “well, because more people entered it than left it,” wouldn’t you think that person was being a wiseguy? Of course that’s true! But it doesn’t tell you anything. WHY did more people enter than leave?
It’s an interesting book, He goes after a lot of weight loss’ sacred cows so to speak. Wondering what people think…
Well, my thoughts on Taubes are long, elaborate and rather unpleasant and Vance Lehmkuhl of the NAVS put it much more eloquently than I probably could:
The entire article is well worth a read:
http://www.navs-online.org/nutrition/dietmyths/atkinsomissions.php
Another good read, questioning the scientific framework of Taubes’ theory, can be found here:
http://www.overcomingbias.com/2008/07/gary-taubes-goo.html
I find myself here because I want to eat low carb yet I play soccer and race MTB (50 and 100km) and I am unsure if I should carb up for games / races. Although my knowledge is limited, I believe there are some problems with your argument
1. In the first study, the subjects were only eating low carb for 1 week, this is not enough time for the body to adapt to efficiently using fat as an energy source and this is the common problem with most low carb excercising studies. Only studies going out beyond 4-6 weeks are relevant.
2. In addition to not knowing the time frame of the 2nd study, low carb does not mean high protein. Fat should replace carbs, not protein. Given protein’s poor conversion to energy you dont need a study to confirm high carb outperform high protein diets. The point of eating low carb is to have the body switch to using fat as an energy source, the study needs to look at high carb diets vs high fat diets, protein remaining constant.
I have not decided what to do yet but I would really be interested to see similar studies performed between high carb and high fat diets and allowing high fat diet subjects enough time for adaption, say 6 weeks.
“1 week, this is not enough time … Only studies going out beyond 4-6 weeks are relevant.” <– This is the issue
Here’s a study that may fit your criteria – http://jp.physoc.org/content/492/Pt_1/293.
I know that 177g is not considered low-carb by anyone’s standards but a couple of observations in the study still point to deteriorated physical performance on low(er)-carb diets:
1. Note that blood ketones rose markedly in the low(er)-carb group, indicating fat adaptation to at least some degree.
2. In the eighth week when both groups ate high-carb, the low(er)-carb group’s performance increased by 18%.
Keep in mind that in most studies testing sprinting or extended periods of low Vo2max (e.g. marathon) all show deteriorated performance with low-carb. It’s actually not surprising if you know basic biochemistry.