Really, I have to remind myself often that most people (even slashdot nerds) are simplistic binary thinkers. They latch onto a certain way of looking at something (ooh, I'm all sciency!) and try to hit everything with the same hammer.

What we are having here is not a scientific study. Nor is it a debate. What we are having here is a discussion. This being a discussion forum. When I bring up something anecdotal, it doesn't mean I am basing a decision or opinion purely on that anecdote. It just means I find it interesting and possibly indicative of a truth. I look at all sorts of anecdotes around me, I look at scientific studies, I look at statistical reports (statistics alone are not science), and I also like to use logical inference when I examine ideas (again, this is not science). When a broad preponderance of different types of evidence points me in a certain direction, I tend to give it credence. It's not an absolute, any more than science itself is a set of absolutes.

Here's an example of empiricism: every damn person on the planet knows that if you want to strengthen a muscle, you have to exercise it, and in general the more intense the exercise, the greater the gains. Of course there are limits after which too much exercise will be counterproductive, blah blah blah, but the core truth is there. Don't need a scientific study to prove that. It is part and parcel of everyone's experience, just like everyone knows you have to breathe in order to stay alive. When the variables get more complex of course it's not always so clear, but one has to be a particularly obtuse person not to agree that in general exercise leads to better health. By logical inference, better health would obviously lead to the likelihood of living longer. Where scientific studies help is in identifying just what the upper and lower bounds are to these benefits. But I'm not here to do your work for you. I'm just shooting the breeze on a Sunday afternoon. If you want that sort of information, complete with box plots, scatter charts, and explanations about sample size and selection bias, well you have access to the same information I do. Get to it.

My overall takeaway from years of reading on the topic is that variety is key. Note that the cardiologist wasn't saying "only lift heavy", but just saying that it's a "should" (I.E. make it part of your routine). If you never lift heavy--as in pushing your body up to and past plateaus--your body never experiences certain types of hormesis. And heavy is relative. I wouldn't recommend some 70-year-old woman be deadlifting 300lbs, but there should be a certain amount of strength exercise that actually...exercises the muscle instead of just fatiguing it.

My routine is a combo of calisthenics, weights, general outdoor work (living on 2 acres), running on occasion, and sprinting on occasion. Let's just say my health and mental attitude have seen an absolute turnaround from the age of 45-49 as I implemented all this. Currently deadlifting up to 345lb and I can tell I'm nowhere near my limit yet.

No. Hell no. You don't understand empiricism at all.

Exactly what anonymous said. Anything can be overdone, and this tends to happen when people go on crazes. The jogging craze was last generation's example. Jogging can be an excellent part of an exercise regimen, but when you do it to the exclusion of all else, for 2 hours a day... you're courting disaster. Ditto for the current "crossfit" craze, where people with zero experience are jumping around in the gym, lifting (or even throwing!) heavy weights with zero ramp-up and zero instruction on good form, and once again you're courting disaster

And how does this have any bearing? I was responding to a claim that any lifespan gained would be spent in exercising. Which isn't the case unless you are way overdoing it.

Yeah, and my experience is that a) most doctors are physically lazy and have abominable fitness, and b) they are stuck on years or even decades-outdated studies of fitness and diet. And, c) they tend to favor medical and pharmaceutical intervention rather than lifestyle changes. This is a natural outcome of how their money is made and their social position in Western society. Which is why I don't have *blanket* trust in their fitness recommendations as a majority. This particular cardiologist was doing his own original research, which is why he came to these conclusions.

I come from a family of doctors and medical people, BTW. I have no axe to grind. I just try to observe as clearly as possible.

Yes really. Anecdotal evidence is still evidence. Consult a dictionary. You asked for citations, which I did not have at hand, but directed you to a couple sites that have lots of them. Knock yourself out.

There is no such thing as conclusive proof in any of these areas. I tend to prefer empiricism and general pattern-recognition to theory-directed research because in the area of health it is so fraught with false positives, statistical failures, presuppositions and downright fraud due to industry influence. But if you browse through PubMed or PLOS for research in these areas, you will be hard-pressed to find negative implications for weightlifting or strength training. Positive implications abound.

BTW back on topic, my point about hormesis/recovery also applies to saunas. Extreme heat puts a certain amount of stress on the body--especially the skin, which if done on moderation produces recovery benefits.

Explain Jim fix?

Easily. Not all exercise is created equal. The jogging craze of the 70s/80s should be dumped into history's dustbin along with the low-fat diet. Also, too much exercise is almost as bad as too little. See my other responses in this thread for more.

There have been many, many studies on this matter over the past couple decades. A couple of my favorite meta-aggregators of these studies are Rogue Health and Fitness and Mark's Dailly Apple (yeah, he's a paleo advocate, but he's also a former top competitive runner, Ironman winner, and currently a sculpted buff dude in his 60s -- and his wife only a few years younger looks like a fitness model). Even more interesting, look into guys like Art Devany. He and his wife are in their mid-70s, yet fitter than most people in their 40s.

Basically, the health promises of the 70s-80s were found to be false along several axes. The most notorious being recommendations for the low-fat, high-carb diet, but also the whole jogging/aerobics craze that started in the late 70s has been found to be empirically a failure. This is what led to the renewed interest in weight-lifting and other strength training. Long-duration, plodding exercise really isn't ideal to longevity. Running 10 miles a day used to be thought the peak of fitness, but really it results in muscle atrophy, heart strain, joint problems, etc...

And the problem with focusing on athletes is generally that they overdo it. Athletes are people singularly focused on *winning* not on health and longevity. Athletes will gladly trade a decade of life for a short-term competitive edge. This is what Mark Sisson (Mark's Daily Apple above) found. His competitive running had him constantly sick and/or injured. He scaled his workout way back, stopped the long-distance running, and focused more on short-duration high-intensity exercise to stimulate the hormesis/recovery cycle, and specifically worked on gaining muscle mass.

There is sort of a golden mean to exercise, recovery, muscle mass, strength, etc... And generally it looks about like the "fitness model" ideal for women and the wrestler physique for men. Muscular but not freakish. Slim but not skinny, low body fat, but not veins showing everywhere... you get the idea.

Side note: I was flying back from SCALE 13x last week, and ended up sitting next to a cardiologist who has been doing research in these areas. His synopsis: we should all be lifting weights, and lifting *heavy*.

Not at all the case, actually. I did the math on this once, based on the most conservative estimate of years added to live for moderate-to-intense exercise.

For one thing, it turns out that the best exercise is of fairly short duration. You can get all the strength training you need in 1 or 2 hours a week. Add another hour a week for some moderate aerobics and, make a few other "life hacks" such as a stand-up desk, and you have every likelihood of adding at least 5 years to your life. And we're not talking about those painful last 5 years where you can't do anything, but 5 years of vitality to your productive mid-life. And a good deal more mobility and independence during your last 10 years.

And let's just say you exercised at 3 hrs/week for 50 years, starting at age 30. By the time you are 80, you have burned up a grand total of 1 year exercising. Those other 4 years are gravy.

How about that? the 80/20 principle at work.

Agreed. It really is depressing. At the moment one of my elder extended family members has been rendered completely disabled due to brain trauma and a few other horrifying incidents, so she must be fed through a tube. The tins of liquid diet recommended by the hospital turned out to be primarily high fructose corn syrup (!). That's the recommended diet for someone in constant bed rest (save a few exercises by therapists), and who CANNOT EVEN TASTE THE FOOD, so why would taste even be a consideration in choosing a high sugar diet? The Big Ag and food industries just have so much corn byproduct that they have to find a market for, so they push it everywhere.

There have been some studies lately suggesting that genetics are not quite the set-in-stone-for-life thing that we once thought: in fact optimal diet and exercise does improve one's genetics to a small degree. WHICH, has interesting societal implications over the long haul...

Actually, it's not even good policy for elite sociopaths if they want to reduce costs. Fact is, life expectancy is still high... we can keep sick and unhealthy people alive for decades, due to the incredible diversity of drugs and surgical procedures, paid for by insurance or medicare. In that sense this policy has created a HUGE drain on our society.

So, the only psychopaths this policy really benefits are the subset who own or are bribed by Big Pharma, and to a lesser degree the armies of cardiologists and dieticians who service this system. We are living in an age when heart disease is the #1 cause of early death. This and several of the other top causes are all directly related to a high-carb, high-sugar diet and lack of exercise. Almost 50% of American adults are on some medication permanently, and 20% of American children are on meds. It is pure insanity. Everything is an intervention rather than a prevention. Take, for example diabetes. You can get rid of it simply by a temporary crash diet (600 calories a day--preferably fats, proteins and vegetables), regular exercise, and then gradually moving back to regular caloric intake, punctuated by some intermittent fasting. In fact, we are finding that intermittent fasting is probably good for everyone. But there's very little money in this sort of cure, so instead we pump people full of meds and send them home to sit and watch TV or play video games.

I fume about this topic, because it is the overriding irrationality of our age. Mathematically speaking, our bad diet and lack of exercise is more dangerous to us than forgetting to wear seatbelts, drinking and driving, keeping loaded guns laying about, and dancing on our roofs during thunderstorms, yet we go on about these ways like unthinking cattle.

Oh. Weather might suddenly become unpredictable? I can't believe it! After these aeons of weather being so predictable and dependable... whatever shall we do???

The idea that weather will suddenly become way more unpredictable than before (whatever "before" is) has zero basis in science. Pure fearmongering. The world has always had unpredictable and changing weather, as well as changing landscapes. Which is why only an idiot (or a modern factory-farming civilization) plants only one kind of crop, and bets the farm (literally) on that crop.

I live in north-central Florida, which is sort of a nexus between subtropical and temperate zones. On a good warm year, I can grow bananas and pineapples. On a good cold year, apples and peaches. With short-term crops like vegetables, I keep an eye on which way temperatures appear to be leaning, and plant accordingly.