Comment by ellyagg | Hacker News Reader

Comment by ellyagg | Hacker News Reader

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Can you list some things that weren't controlled for that you think would lead to both increased one rep max and longer life expectancy?

As Edward Tufte says, "Correlation is not causation but it sure is a hint." That increased strength improves life expectancy should be the null hypothesis. At least at the one end, extreme frailty is a common eye test for poor health. Since this isn't a scientific journal here, but a discussion, I think most of us would agree that stronger people often have more resources to ward off disease, cope with temporary reductions in nutrient bioavailability longer, can defend themselves from threats more easily, and can avoid more dangerous falls by maintaining their center of balance. And that's not a comprehensive list.

Personally, I'm satisfied that increased strength reduces all cause mortality and I believe the link is strong enough to be actionable now. I'm an evangelist for it among my older friends and relatives. One way strength reduces deaths is by preventing common injuries, e.g., falling and breaking a hip. A recent study showed that a simple graded test of sitting on the ground to standing could differentiate mortality risk sharply. While we can't measure how much strength and how many years it adds, not least because that's just a vague question, the link here was almost an order of magnitude from the lowest grade to the highest grade for one repetition of standing from the ground.

http://www.cbsnews.com/8301-204_162-57559095/sitting-and-sta...

http://cpr.sagepub.com/content/early/2012/12/10/204748731247...

The big issue is sub populations. I work on similar large studies including genomic data and it is quite frequent to see associations of the form "central americans have a lower rate of disease x" and "central americans have a higher rait of factor y."

This produces a statistical association but, especially with genomic factors, factor y can just be something that randomly identifies the group.

Similarly in this data set you might find a group of people who have higher strength because of genomic factors that make it easier for them to build strength from the same workouts as "normall" people. These people might also come from a subpopulation (farm famlies, people of Slavic heritage who knows) that has lower rates of cancer for genomic or cultural reasons. Even a small number of such people can make the association look significant though it will disappear once you remove them.

It could also be something like a certain food or diet making it both easier to build strength and preventing cancer.

There are extremely good reasons, aside from this study, to think increased strength would improve life expectancy.

This is also true for endurance running, wine, coffee, beer, olive oil, eating lots of meat, not eating lots of meat etc.

The first example I can understand, but I am not following you with the rest.

They are all things that have been shown to extend lifespan in various studies in the past few years. Some of these studies were observational like this, some where done by giving mice ridiculous doses etc but they all got picked up by the media.

Some of these results are probably valid but if you want to scientifically extend your life you need to do so with statistical rigor.

Show me a rigorous study demonstrating that one can only lengthen their lifespan by making decisions based on evidence at the level you demand.

I don't believe you make every, or even remotely close to most of your decisions in daily life by this standard. Human brains aren't designed to and don't have the energy to do so.

No I don't...I take my doctors advise but I also exercise and eat well because I enjoy it.

However, in my job, I analyze large medical datasets. You will understand if I get a bit pedantic about such things.

Doing some strength training is a probable plus on several fronts with few risks. However if I am advising doctors or the presidential physical fitness council to recommend strength training vs endurance training vs focusing on diet on an institutional level I need to look at the evidence for each with more rigor.

Stop smoking, buckle your seatbelt, lose a few pounds and take tons of Vitamin D. Everything else is conjecture.

Except don't take tons of Vitamin D http://www.sciencedaily.com/releases/2012/05/120529102346.ht...

No, the evidence for each of those is far more limited, ambiguous, and in one case contradictory. You would not advise your parents to maintain strength enough to stand because only prospective studies link standing strength to longevity?

There was a recent study which found that running only increased life expectancy if you were running 10-20miles (or km, memory hazy) per week. More than that and life expectancy decreased again.

So endurance running, which I would guess you would categorise as marathon+ will decrease your life expectancy.

Edit: /s/will/could Depending on how much running you already do.

That is kind of my point. Everyone thought running was good but more rigorous analysis showed that it is not that simple.

Running 4 hours per week for 20 years will add 6 months to your expected lifespan. However, those 6 months will have been entirely spent running. So, plan accordingly.

Exercise demands time so in terms of increased life expectancy versus time spent exercising it's probably a wash. Speaking personally though, I feel awesome when I exercise regularly, and when I don't, I don't.

Exercise for higher quality of life and a better looking body, the longevity benefits are overrated.

You shouldn't forget to compare general health of one who runs versus one who doesn't. Not only just wellbeing, but sick days (missed on income), medical bills etc.

You are of course talking about monkey bar fighting over a pit of snakes, right?

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