Exercise is not good for longevity.

[Sibiriak]

Todd makes some excellent points about the limitations of this study.   As he mentioned,  there has already been some interesting and detailed discussion on the  CR/bone health issue by Dean P., Michael R. and others.   I personally  don't practice severe CR, so  I'm not inclined to spend the time to dig up those posts at the moment, but for those interested in the topic,  I suggest they do so.

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Todd Allen:   I wasn't able to get the full paper through scihub but my expectation is variations in diet and exercise could play a big role in the outcome I doubt this single study thoroughly examined all factors.

Yes, it's hard to say anything concrete without access to the full paper.   I would certainly like to know more about the regular diet (RD) used in the study.

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There were four groups of mice in all—a group on a regular diet (RD), a group on a calorie-restricted (CR) diet, a RD group that exercised, and a CR group that exercised. Mice in the CR group ate 30 percent less than what RD mice ate.

For context in humans, according to the United States Department of Agriculture (USDA), a 'moderately active' woman around the age of 30 should consume 2,000 calories per day. A 30 percent reduction would equal a diet of 1,400 calories per day, which is around the amount suggested to most women trying to lose weight at a rate of one pound a week.

https://medicalxpress.com/news/2019-09-restricting-calories-bad-bone-health.html

Does that suggest that the CR diet was a very serious weight-loss diet (for six weeks),  not necessarily analogous to a long-term, steady-state CR diet?  Again, I haven't read the paper, and on top of that,  I'm not an expert at all in the design details of CR mouse studies like some of the other posters here are.

Edited September 13, 2019 by Sibiriak

[Mark Nederland]

I agree with you but today I read the book "The longevity code" and they talk about hormesis and I was thinking about your post. What do you say about this?

"Exercise is also a form of hormesis. The most important reason why exercising is healthy is because it damages the body. An hour of cycling or swimming makes our cells work much harder than they usually do. They become overtaxed and slightly damaged, which you can feel the next day when you wake up with sore muscles. However, this damage shakes our cells awake and prompts them to repair and better protect themselves for the next time you go for a bike ride or dive into the pool. As the cells keep arming themselves against that kind of damage, they are then also better protected against other kinds of damage, such as that caused by aging processes."

 

Edited September 17, 2019 by Mark Nederland