Can you help me with a review of this article on exercise and calories burned?

[Wigberto Marciaga]

Hi, blessing in the name of Yeshu. (It's my way of greeting, it's not exactly procelytism)

I have been analyzing an article published by a man called Shaun Ward which is a response to studies on the Hadza by Herman Pontzer. I'm not very good with mathematics, I admit it. I do not rule out that there could be some errors in the text I published.

url deleted

In the first link of the article is the study I used, which is one of the oldest published by Pontzer on the subject. In that study there is a table with the percentages of body fat for each group.

The conclusions I reached are that the amount of calories burned with exercise is very low, but it seems that it would not be zero as I understand Pontzer has suggested.

However, I mention here (although it is in the analysis I do in the article) that I saw the basic data to question Pontzer's version of daily energy expenditure in the article published by Shaun Ward. However, it seems to me that there is a lack of data to be able to determine the matter more precisely, so it cannot be assured that H. Pontzer's position on the matter is wrong.

If you could help me by reviewing my analysis, if you want. It's not that extensive. 

[swansont]

!

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[Wigberto Marciaga]

Sorry, I must be more careful next time.

Now maybe I'll go to sleep, so I would put the data that I consider relevant, God willing, or maybe a copypaste.

[Wigberto Marciaga]

I tried to edit the previous comment, but it didn't work. I think that with this data you will be able to verify the matter:

1. https://mynutritionscience.com/exerciseweightloss/ (26% extra adjusted to the proportion of body mass discarding fat-free mass.)

2. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0040503 (The study in question. Find fat percentages in graphs (table)

What I found is that the difference could be explained by the greater proportion of muscle mass of the Hadza, although there is the possibility that there is an extra expenditure for exercise of approximately 8% of the total calories burned in 24 hours.

https://www.unm.edu/~lkravitz/Article folder/metabolismcontroversy.html (I used this information for the rough estimate)

It seems to me that there is a lack of data to reach a more concrete conclusion. But, the evidence seems to point more to the version of Pontzer's studies.

Regarding exercise, I have maintained that it helps you lose weight, but not necessarily because it burns more calories. But because long-term cardiovascular exercise, like that of the Hadza, induces catabolic processes and net burning of calories through oxidation of adipose tissue.

[Wigberto Marciaga]

I insist, I can't edit.

I summarize: My idea is to adjust the fat percentages that appear in Pontzer's study (13.5% Hadza, 22.5% Western, on average).

The other fact is that a man with 20% body fat would burn 20% calories from muscle and 5% from fat.

The goal was to determine how much of the 26% extra calories that Shaund says the Hadzas burn by adjusting for fat-to-muscle ratio instead of fat-free mass as Pontzer had done in the study.

Please remember that these are all approximate figures.

I calculated that of the 26%, only 8% of total caloric expenditure could not be explained by the greater percentage of muscle of the Hadza. But that 8% would be subject to determining what values were used to estimate 26% of Shaun's items.

I hope that now I have made myself explain this. There is more, but the matter would be somewhat more extensive.

Blessing.

Edited April 19 by Wigberto Marciaga

[CharonY]

18 hours ago, Wigberto Marciaga said:

What I found is that the difference could be explained by the greater proportion of muscle mass of the Hadza, although there is the possibility that there is an extra expenditure for exercise of approximately 8% of the total calories burned in 24 hours.

The TEE is dependent on fat-free body mass and Hadza adults are not only leaner, but are also smaller. Specifically the component relating to fat-free body mass is the BMR. In the cited study TEE was measured, but BMR was calculated based on equation given by a paper by Henry (2007), which include age, body weight, height and sex. Physical activity was estimated as TEE/ calculated BMR. So body fat is not measured or otherwise included, from what I can tell. 

 

 

[Wigberto Marciaga]

1 hour ago, CharonY said:

The TEE is dependent on fat-free body mass and Hadza adults are not only leaner, but are also smaller. Specifically the component relating to fat-free body mass is the BMR. In the cited study TEE was measured, but BMR was calculated based on equation given by a paper by Henry (2007), which include age, body weight, height and sex. Physical activity was estimated as TEE/ calculated BMR. So body fat is not measured or otherwise included, from what I can tell. 

 

 

The study adjusted for weight, so that variable being the same from Shaun and Pontzer's point of view, I simply discarded it and was left only to check the fat-muscle ratio and its impact on energy expenditure, which is where Shaun differs. with Pontzer who conducted the study adjusted for fat-free mass.

The TEE would depend on fat just like the BMR, since one is total energy expenditure and the other energy expenditure at rest. The thing is, Pontzer was limited only to energy expenditure adjusted for fat-free mass, and that's what Shaun says was wrong in his study.

Edited April 19 by Wigberto Marciaga