And as it turns out, antioxidant supplements appear to cancel out many of the beneficial effects of exercise. Soaking up those transient bursts of reactive oxygen species keeps them from signaling. Looked at the other way, oxidative stress could be a key to preventing type II diabetes. Glucose uptake and insulin sensitivity aren't affected by exercise if you're taking supplementary amounts of vitamins C and E, and this effect is seen all the way down to molecular markers such as the PPAR coactivator proteins PGC1 alpha and beta. In fact, this paper seems to constitute strong evidence that ROS are the key mediators for the effects of exercise, and that this process is mediated through PGC1 and PPAR-gamma. (Note that PPAR-gamma is the target of the glitazone class of drugs for type II diabetes, although signaling in this area is notoriously complex).
Interestingly, exercise also increases the body's endogenous antioxidant systems - superoxide dismutase and so on. These are some of the gene targets of PPAR-gamma, suggesting that these are downstream effects. Taking antioxidant supplements kept these from going up, too. All these effects were slightly more pronounced in the group that hadn't been exercising before, but were still very strong across the board.
This confirms the suspicions raised by a paper from a group in Valencia last year, which showed that vitamin C supplementation seemed to decrease the development of endurance capacity during an exercise program. I think that there's enough evidence to go ahead and say it: exercise and antioxidants work against each other. The whole take-antioxidants-for-better-health idea, which has been taking some hits in recent years, has just taken another big one.
But take heart: exercise may not be nearly as great as we've been told. It definitely helps ward off diabetes, but most of that benefit comes at very modest levels. It might have modest effects on depression, heart disease, and cancer, but it's hard to tell because of selection effects: if you stay depressed, you probably stop exercising. And it's hard to tease out the confounding factors in the other two: the exercisers are also thinner, more educated, and less likely smoke than the others. I was shocked to find out how much of the difference between women's and men's life expectancy was accounted for by their different rates of smoking, and it seems the same sort of thing may be operating here.
Oh, and exercise probably won't make you thin, either, particularly if you're the sort of person who finds it hard to lose weight. Your appetite eventually seems to increase enough to compensate.
Basically, unless you're at risk for diabetes, Kolata says there's no solid evidence that exercise will do much besides make you sweat.
Of course, my idea of exercise is biking to work, so you'd expect me to say that.
It all depends on the type of exercise, the intensity and the general choice of foods... so this argument is a bit simplistic.
There is a world of difference between low intensity jogging and high intensity sprinting or chronic exercise frequency and intermittent frequencies.
The benefits of certain types of exercise come from a greater quality of life in aging as it prevents the loss of physical capabilities and retains lean body mass in older individuals and improves hormone profiles.
Unfortunately most lab studies focus on very simplistic weightlifting programs or chronic use of treadmills which is far from ideal.
"Basically, unless you're at risk for diabetes, Kolata says there's no solid evidence that exercise will do much besides make you sweat."
Sounds like b.s. to me, however one needs to differentiate between different levels of exercise. I remember reading about a study that tracked Harvard alumni for a few decades and found that the benefits of exercise were significant, but only for those who exercised enough to burn 2000 calories or more per week. That's consistent with what I've noticed from my own experience, but researchers ought to be able to isolate the effects of exercise versus weight loss empirically: Have a control group that doesn't exercise and eats some normal number of calories per week (maybe 17,000 each, for a group of 200lb men?), and another group that eats 2000 more calories but burns 2000 calories exercising per week. I'd bet that the second group would end up being healthier than the first.
What about cardiovascular endurance -- the kind measured by the stress ECG? Looks relevant to general well-being. Exercise -- not even of a particularly regular and/or gruesome variety -- certainly makes a difference there.
Is Kolata a 300 lb couch potato?
I would also question the anti-oxidants used in the study; those in supplements or from foods?
I'd much rather eat an orange-fleshed melon than take a pill.
An I'll get my exercise growing that melon.
This seems to be a rather odd post for Megan to be making. On the one hand, health outcomes are better for people in countries with some form of 'socialized' medicine not because of the health care delivery system, but because of 'healthier lifestyles'. But on the other hand, those lifestyles, as per the post above, don't really seem to be all that beneficial. But - wait for it - on the third hand (or gripping hand), we all know that people living healthier, longer lives actually cost the health care system more, at least according to some of Megan's conservative commenters.
A wealth of contradictions, as they say.
Me? I exercise to keep my mind sharp.
Its not working for you.
Well, these are only contradictions if you interpret them as such (willfully). For example, the healthier lifestyles of many European lifestyles refers to the Mediterranean diet, which has nothing to do with exercise and everything to do with the types of fat and amount of cholesterol ingested. So 'those lifestyles' and this post have little to do with one another. Also, you added in your own adjective with people living longer, 'healthier' lifestyles. Longer lifestyles are what cost more, i.e. a family that doesn't want to let grandma pass away despite the fact that she is in a hospital on a ventilator with little to no chance of recovery. That is expensive, not older, healthier individuals living without round the clock care. So perhaps you need to exercise more so those contradictions can disappear along with the your mind's dullness
Strange - the Mediterranean diet also benefits Northern and Central Europe countries. And Canada. At the same time not doing so much for Portugal.
Yes. The only key to a healthy lifestyle is a Mediterranean diet. And there's no likelihood that living longer would result in more doctor visits. Brilliant. You should definitely exercise more.
"Oh, and exercise probably won't make you thin, either, particularly if you're the sort of person who finds it hard to lose weight. Your appetite eventually seems to increase enough to compensate."
Um, yeah, which is why in order to lose weight you have to exercise and stop eating whenever you're hungry. I used to be 345 lbs, then I started running until I was 205 lbs. I don't think it's a coincidence.
Congrats. But inquiring minds want to know: did you take antioxidants after you started running?
Nope
Hey, I'd be interested in knowing, did you happen to diet while you started your running regime? Assuming you did, and judging from my experience, I'd say you would have lost that weight regardless of whether you exercised.
Yeah, I did diet. I ate 1500 calories a day and ran like a maniac.
Maybe I would have lost weight anyway, but not that fast (90 of those pounds came off in about 6 months). I mean, it's not too hard to figure out. Exercise burns calories. Eating puts them on. Exercise more, eat less. Do only one or the other, and you won't lose as much weight. Would Helen have won "The Biggest Loser" by eating less and watching TV? Don't be silly.
With that said, I'm perfectly willing to believe that moderate exercise will have little effect on weight, just like how reading one Stephen Hawking book won't turn you into a physicist.
Damn, and that (post below without reply) was my dream for my dotage. Read Hawkins, study black holes.
For whatever it's worth, my experience. I am a distance runner who's fought bouts of over-usage injuries which have periodically put me on the shelf for a couple months at a time.
When not running 20 miles/week, my normal diet decreases from 3000 calories a day to about 2500; I just don't have the same appetite without the long runs. For the first 2-3 weeks I hold weight, but lose muscle. After that I gain weight, even with my calories reduced. Right now I've been on the shelf for 2 months, and I've gained 12 lbs.
When I get back to running, I rapidly lose the weight in a week or two. My appetite increases, and then my weight stabilizes. From there, I see very little weight loss with additional mileage; when deep in training for marathons, I don't lose more than an extra 5 lbs even though I'm burning 6000+ calories a week (and eating like a horse to compensate.)
Don't know what it all means, but it seems to me there are 3 distinct regimes. 1 - low increase in exercise (>1000 calories per week), in which I gain weight even with low calories. 2 - moderate increase in exercise (1000 - 3000 calories per week - rapid weight loss, followed by increase in appetite. I bet weight loss could be continued with a restricted diet.) 3 - heavy exercise (3000 + calories per week) - diminishing returns due to high refueling cost to prevent breakdown.
Oh, and I've always vitamin C loaded when training for marathons to keep away colds; one week being short of breath is very costly. Perhaps I'll have to try skipping that next time.
"Oh, and exercise probably won't make you thin, either, particularly if you're the sort of person who finds it hard to lose weight. Your appetite eventually seems to increase enough to compensate."
I love this statement....being written by an economist, it's startling.
You mean as the demand for calories increases (body's needs), the supply will also increase unless someone has the discipline/desire to restrain that supply?
Holy moly! :)
I've read a ton of articles like this before. I even conducted a metabolic study of blood lipds on people who ate wisely and either A. Exercised at moderate intensity for 30 minutes 5 times a week or B. Accumlated moderate intensity physical activity equalling the same as the exercise group.
There are alot of academics who collect a limited field of data and interpret it for wide-ranging implications.
As pointed out by another commenter, not only does exercise improve life in a huge variety of ways but it is prolongs the durability of the body as old age comes on. One of the declines of old age is the loss of muscle mass (Atrophy) and bone density (osteoporosis, which is thought by some to be primarily caused by a lack of stress on the bone due to muscle loss/lack of use).You lose the ability to walk around easily, go up stairs, open jars, etc....but you also increase your likelihood of falling down and breaking something like a hip.
No pill is going to prevent that; you need physical stress to first build, and then maintain, and then slow atrophy as you age. That's called exercise.
Joe
Oh, and exercise probably won't make you thin, either, particularly if you're the sort of person who finds it hard to lose weight. Your appetite eventually seems to increase enough to compensate.
Exercise burns far less calories than most people suspect. Combine that with it taking a deficit of 3000-3500 calories to lose a pound of fat and you can see why moderate exercise may not be effective. If you burn 200 calories a day exercising, that's easily offset by going out drinking and getting pizza on Saturday night. Even without that, it's only 1/2 pound a week worth of exercise. Also, as you lose weight you require less calories so you'd need to adjust your exercise or diet accordingly.
Secondly, a lot of people consider exercise things I'd never consider. I've heard people justify that they exercised 20-30 minutes today because they went to the mall shopping. I'm also wary that a lot of the people who don't exercise lie to the researcher, because who wants to admit to the researcher they were too lazy to exercise this week?
Last, taking things in pill form seems a little strange. I wonder if you get your antioxidants/vitamins/minerals by eating your fruits and veggies if that has the same effect as taking a pill.
I know people who take theirs with their beer and pizza.
I'm pretty sure one of the major benefits of exercise over diet is the increase in metabolism due to muscle mass; if you hold calorie intake fixed, but increase muscle mass, you will lose weight since muscles burn more than fat (I've read 3x, with the absolute number varying from 6 - 50 calories/day/lb muscle.)
As someone who's lost 30 lbs over the course of 2 months without exerc ise and without supplements, this study rings true to me. I used to be a gym nut, but 50 lbs of fat later, I realized that I wasn't building up muscle. The key? Starve yourself. Well, not really, it was more like eat 500 calories a day and take the weekends off. You do have to get used to being hungry though, I must admit. And it probably works better for guys, since women seem to have a problem with appetite suppression.
Running a mile at a moderate pace burns approximately 150 Calories. So running seven miles burns over a thousand Calories. Regardless, as Dickens once pointed out, the difference between happiness and misery is a few shillings. If you're ahead by even pennies at the end of the month, you can be said to be happy, or at least have no cause for complaint. Behind by a few pennies? That way lies the poorhouse.
And so it is with diet and exercise. Having a even 200-Calorie deficit at the end of the day or week means that you will lose weight in the long term. Not so the other way.
Regardless, if Megan wants to claim that diet and exercise don't lead to better health outcomes, then she can't plausibly claim that people in other countries enslaved by socialized medicine are living longer and in better health because of 'healthier lifestyles'.
You should read what Megan wrote, rather than what you wish she wrote. All she said is that it's hard to isolate the effects if exercise, since people who exercise also make other good lifestyle choices.
So while one can conclusively say that good lifestyle choices lead to good health, one can't pinpoint *which* lifestyle choices were most important.
Running a mile at a moderate pace burns approximately 150 Calories. So running seven miles burns over a thousand Calories.
This is highly misleading, if not simply untrue. For a 150 pound individual, running a mile at a "moderate" (let's say 9:00/mile) pace will burn 110 calories. If you cranked the weight up to 200 pounds and the speed up to 6:00/mile, then you might be approaching 150 calories -- but, of course, it is highly unlikely that a 200 pound individual could run more than one mile at that pace (if that).
And in any event, that same person probably would burn 200 calories an hour sitting on the couch, so the net burn from running is about 20-30 calories lower (depending on whether it is a 6:00 or 9:00 mile).
Bottom line: Assuming that 150 pound person (it is overwhelmingly more likely that someone able to run 7 miles at a decent clip will be 150 pounds, rather than 200) and splitting the difference on pace, you get a net burn of 85 calories/mile or so -- so that 7 mile run is going to burn more like 600 calories.
Me? I exercise to keep my mind sharp.
I do it because I want more children.
science journalism is notoriously lazy, so you have to go straight to the source.
first off, the title (megan's) is misleading: the authors themselves state in their introduction the entirely uncontroversial claims that:
second, human studies are notoriously hard to control, because of our diverse genetic backgrounds, lifestyle, environmental exposure, etc. this is different from inbred mice contained in a controlled environment and easily controlled. so the number of subjects (40) would be great for a murine study but is a bit trickier to draw conclusions from with humans.
here's what the authors could control for (entirely dependent on clinical history and patient honesty)
well the damn thing ate my post.
just read the original paper, it's free.
the study is interesting but doesn't make the strong conclusions that non-scientists are drawing from it.
the study is interesting but doesn't make the strong conclusions that non-scientists are drawing from it.
That sounds like virtually every scientific study, court case, or economic projection ever made.
Well, except for the 'interesting' part.
As I stated before, the type of exercise is really key. Compare a 50 year old marathon veteran with an olympic lifter, powerlifter or discus thrower of the same age and you will see a world of difference in body composition, posture and explosive strength.
The difference is that they train for explosive power and strength instead of low level endurance.
Also, the problem with all of these studies is that they look at exercise in isolation of a context and for a short term duration and almost never tap the expertise of people who have made serious body composition changes (fat loss or muscle gain) or who have helped people do the same.
People who have trained their whole lives change their routines, protocols and weight/rep/speed schemes on a regular basis as their bodies adapt to their old routines.
But if you exercise AND control your appetite (ie. less calories), you will lose weight. If you just control the appetite/calories and don't exercise, you'll still lose the weight, just over a longer period of time. But exercise and eating a hamburger that says it has anti-oxidant additives to it will still store more fat in your body thanks to the hamburger. And if you exercise but still eat crap, the exercise will be canceled out. But I have always found that if you do BOTH, you will lose weight. It's all a numbers game in the end.
There is also a difference between losing weight and losing body fat. You can change body composition without losing weight. Skinny-fat people may have a low BMI but no better health outcomes than an obese person. A better indicator of health is leanness.
David - you are the only one talking sense... Are you an Art De Vany devotee?
I should note that these exercise studies are widely misunderstood/misrepresented. The point usually is not that exercise cannot promote weight loss or significant health changes. The point usually is that the amount of exercise necessary to do so is unrealistically high for the vast majority of the population. Put simply, the studies usually suggest that 90 minutes of daily moderate exercise, or 60 minutes of daily vigorous exercise (e.g., hard running or very hilly biking), are required, and it's just not feasible to expect more than a tiny minority of people to go out and do a 10 mile run every single day of the week for the rest of their lives. But for those who ARE willing to do that, they are going to see pretty significant weight and health benefits.
I'm a pretty good example of this. I lost a ton of weight about 5 years ago through diet and exercise. I also exchanged a smoking habit for a marathon habit, and I currently run 60-80 miles a week (to make it simple, lets say 70 miles at 7:00/mile pace on average, for a total of 70 minutes of vigororous exercise every day). I eat what I want -- at 60 miles/week, that means I don't gain weight regardless of caloric intake; at 70, I lose weight no matter how much I eat; at 80, I lose weight quickly and have to supplement with shakes. I have maintained the initial weight loss throughout this time (I was 200 pounds; I fluctuate between 140 and 165 depending on where I am in training). My blood pressure has dropped from borderline high to well within normal. Cholesterol from morbidly high (280, with an 8.5:1 ratio) to the low end of borderline high (220, with a 3.5:1 ratio -- so most of the "high" part is do to HDL).
This started off as a good article by examining the vitamin and antioxidant fad, but the evidence cited against the benefits of exercise are limited at best--for example, there is nothing mentioned about the effects of exercise on white blood cell production. It's also a no-brainer that exercise without appetite control will probably not lead to weight loss, but that does not mean that exercise has no benefit.
Thank you for pointing this out, Nimed. And no, contrary to what Nola says, there have been posters here in the past who have claimed that exercising was part of those 'healhier lifestyles'. The problem with these sorts of arguments, as Nola demonstrates, is that what constitutes a 'healthier lifestyle' is a moving target. There was one poster who was very upfront about the tactic not so long ago: he claimed that not only was the burden of proof on those who advocated 'socialized' medicine that superior outcomes were not due to lifestyle choices, but that every variable had to be controlled for.
I'll give Nola a pass on this one, since he might not be aware of the history, but only if he concedes that those on his side of the aisle were wrong to make this claim.
Not also the contradictory claims above: "And there's no likelihood that living longer would result in more doctor visits." So if one lived longer due to these healthier personal habits, apparently one will end up making more visits to the doctor, which will cause medical costs to rise.
Shrug. It's not an important point. But looking here, I see that someone running a moderate pace of 7.5 minutes per mile and weighing 160 lbs does indeed burn approximately 1,000 Calories (that's a large 'C', btw; the chemists calorie is 1/1000 the dieters.) Regardless, whether it's 1,000 Calories or just 500, the point I was trying to make is that it doesn't really matter, so long as the output is greater than the input. Even - as I've already said - the difference is just 200 Calories a day or a week. Not particularly controversial, actually.
But looking here, I see that someone running a moderate pace of 7.5 minutes per mile and weighing 160 lbs does indeed burn approximately 1,000 Calories
I get 832 calories (gross) for a 155 pounder, or roughly 118 calories/mile (incidentally, this is slightly high -- most burns at that speed are estimated to be close to 110). But again, that isn't the relevant calculation -- you need to figure out how many more calories are burned vis a vis sitting on the couch. And that answer is roughly 670.
I also note that 50-odd minutes of running at 7:30/mile pace is probably going to be impossible for anyone who is not (a) already a decent runner (meaning a sub-3:30 marathoner), or (b) an adolescent or young adult male.
A decent runner, sure, but a sub-3:30 marathoner? 50 minutes running a 7:30 mile is 6 2/3 miles, or slightly more than a 10K. You don't need to be a sub 3:30 marathoner to run a 47-minute 10K.
Perhaps I overestimate the difficulty of running 7 @ 7:30 pace. Though that effort is the equivalent of a 3:32 marathon according to the running calculator I use.
http://runworks.com/calculator.html
I'm none of those things, yet I run seven miles at a pop three or four days a week at that pace. And I've been doing that for at least five years now. More: eight years ago I had a two-pack-a-day habit, menthols and regulars.
Congrats. I suspect that with three months training (a little speedwork and some long runs) you'd be a sub-3:00 marathoner or close to it.
What I love most about information that poses exercise as virtually useless is its complete disregard for the way humans are built. Yes, evolution totally shaped us to be couch-potatoes. Uh huh.
Many moons ago a fine writer, distance runner, and doctor wrote these lines...paraphrased:
"It isn't that exercise will add years to your life; it's that it adds life to your years."
It's what exercise does for the mind far more than what it does for the body.
The unexercised life is not worth living.
I would like for someone to admit that "exercise science" might be better termed "exercise art." Of course, there's science to the anatomy and physiology and chemicals and calories. But how an individual body will respond to any fitness program is more of an art. (And often includes the interaction of the psychological and emotional parts of a person, not just physical.)
I exercise to help stay fit and control my weight, because I come from a family of morbidly obese people. But the greatest benefits of exercise for me have been feelings of confidence and empowerment and learning skills like setting and achieving goals that have carried into other areas of life.
Well, if I can do it - I quit smoking the day I turned 40 - I imagine most anyone can[1]. The key is what we've all been told for years: gradualism, persistence, and forming good habits.
And my doctor, contrary to what has been posted above, thinks that aerobic exercise is very, very good for you.
[1]Like a lot of other people, I'd tried quitting several times before. The final effort involved smoking two packs of cigarettes from 6:00 pm to the stroke of midnight. Got me over that 48-hour hump that kills so many good intentions.