Dr. McDougall's Online Discussion Board

New evidence that exercise, while important for health, is *not* a good way to lose weight comes from today's NY Times.

An anthropologist studied kids in Ecuador, one group living out in the countryside, the other in the city:

"The in-depth study found that the rural children, who run, play and forage for hours, are leaner and more active than their urban counterparts. But they do not burn more calories day-to-day, a surprising finding that implicates the urban children’s modernized diets in their weight gain." (my emphasis)

One explanation offers an evolutionary perspective:

"Dr. [Herman] Pontzer concluded that, during evolution, we humans must have developed an innate, unconscious ability to reallocate our body’s energy usage. If we burn lots of calories with, for instance, physical activity, we burn fewer with some other biological system, such as reproduction or immune responses. The result is that our average, daily energy expenditure remains within a narrow band of total calories, helpful for avoiding starvation among active hunter-gatherers, but disheartening for those of us in the modern world who find that more exercise does not equate to much, if any, weight loss. (Dr. Pontzer’s highly readable new book on this topic, “Burn,” will be published on March 2. )"

Full article:
https://www.nytimes.com/2021/02/24/well ... mazon.html

Thanks

Just to put this in perspective, it’s not exactly “new” info.

A few examples....

- There is a reason why the McDougal Programs motto is “It’s the food,” why I have always said, “you can’t outrun a bad diet” and why our main recommendation is to not be sedentary and just aim to be moderately active for about 30 minutes per day.

- Many other experts have said that diet is at least 80-90% of the equation

- there’s an excellent book called The Exercise Myth (published in 1984, 37 years ago)
https://www.amazon.com/dp/0553257315/re ... HDDHYWY05N

- the famous debate between Nathan Pritikin and Jim Fixx who thought his exercise would save him from his bad diet goes back to the late 70’s, early 80’s. Jim Fixx died while jogging in 1982 at the age of 52.
https://www.nytimes.com/1984/07/22/obit ... as-52.html

Also, if you are interested, I have a thread that has been following Pontzer’s work on his “exercise paradox” for some time
viewtopic.php?f=22&t=57403

In Health
Jeff

Diet is the most important thing IMO but there is some debate that says Jim Fix would have probably died sooner than he did if not for the exercise, but IDK. He was overweight, smoked, and had a horrible family history before he took up running, so you decide.

The body definitely seems determined to adapt to keep things the way it prefers. I would imagine that this is true for the calories that come from food as well. If we create a deficit with food, the body will adapt by lowering calorie burning in other areas. It seems that the only way to keep the body from adapting is to adjust your food and exercise every couple of weeks, before the body begins to adapt. Is this correct?

Susan5 wrote:The body definitely seems determined to adapt to keep things the way it prefers. I would imagine that this is true for the calories that come from food as well. If we create a deficit with food, the body will adapt by lowering calorie burning in other areas. It seems that the only way to keep the body from adapting is to adjust your food and exercise every couple of weeks, before the body begins to adapt. Is this correct?

For most everyone, the issue is energy balance and diet is the most important factor. Understanding calorie density and satiety allow us to lower calories without going hungry or starving.

There is a relationship between your total mass and your RMR (covered in other threads on metabolism). So, if you were 200 lbs and had a RMR of 2000 and lost weight and went to 175 lbs, your RMR would be about 1,750. I give an example of this in the thread on plateaus, which are really just points of metabolic equilibrium, not adaption.

The concept of the “starvation mode” as discussed and applied to overweight and obese people is a myth and there are 3 or 4 threads on it where i cover the issue. You can't eat more calories to lose weight.

However, when we truly hit the stage of starvation (not starvation mode) and our reserves of body fat go below the level of essential need (about 5% for men and a little higher for women) the body adapts to try and conserve energy as one must eat or they will starve to death fairly soon. They must eat to gain weight and not die.

viewtopic.php?f=22&t=17541&p=160647

The exercise paradox is an adaption to high levels of energy expenditure which we would not see at the recommended levels of 30-60 minutes per day, which is where we see the greatest benefit.

Jeff

What about the "muscle confusion" that individuals who lift weights talk about, to keep the body from getting used to (adapting) a particular work out? Is that not a real thing, or am I confusing two different concepts?

Susan5 wrote:What about the "muscle confusion" that individuals who lift weights talk about, to keep the body from getting used to (adapting) a particular work out? Is that not a real thing, or am I confusing two different concepts?

Different concepts.

However, "starvation mode" and "muscle confusion" do have one thing in common, they are both myths

In Health
Jeff

Ahh, okay, good to know. Thank you!

Absolutely. Exercise is VERY important, but too often people think they can live at McDonald's as long as they exercise. Sadly, I see a LOT of overweight people running in the park where I hike with my dog (we do 4-6 miles most days). I've seen the same folks for a year--they are not losing weight. I wish I could tell them how to do it!