Lots of people seem to harbor the notion that training for a marathon is a healthy pursuit, what does science say about this ?

tightWeekly · 2012-05-25T17:36:25.493370+00:00

The bigger problem with running (and extreme endurance training -- see swimmers) is that there's no skeletal loading

Wait... so first you quote a guy who says most of the stress fractures come from runners, then you turn around and say that running has no skeletal loading? Well, which is it? Stress is loading.

So they don't get enough calcium. Nobody does. Still, the doctor says "most of the stress fractures he sees are in runners." So are we to believe that weight lifters get enough calcium? And the guys who play basketball down at the Y four times a week? And that woman who goes for 5-mile hikes?

I'm pretty sure the woman who hikes and the dudes who play basketball don't put the same stress on their bones as an endurance runner. A stress fracture is not the same as having osteoporosis. If it were, no teenager would ever break a bone.

He meets you halfway with the calcium bit. Calcium, though, isn't going to bulk you up to be non-competitive. What's the reason, then, competitive runners aren't taking it?

I'm pretty sure I summed it up at the end of my last post: some people are idiots.

TL;DR: Even doctors who study this aren't in agreement. But most of it's the running. Runners are addicts and want to blame anything else.

Yeah, ok. You yourself post a quote from a researcher blaming fast food and middle aged runners trying to balance too many things, then you turn around and say "But most of it's the running."

We have another doctor saying it's a combination of genetics and diet, but you still think it's running.

You even mention that the doctors who study it aren't in agreement. But you're still pretty sure it's the running.

Yeah... ok. There's a difference between something putting you at a high risk for a condition and something causing a condition. Blame has nothing to do with it.

tightWeekly · 2012-05-25T17:15:43.281567+00:00

Which arguments?

That paleolithic humans could sprint up to 30mph? So what... the slowest antelope in interior Africa sprint over 40mph. No human could ever out-sprint a quadruped.

That running slowly is for retreat from a predator? That's pretty retarded. The animal that does the killing is the one which has the luxury of selecting the time of the engagement. Prey animals must always be fast sprinters, because they must always outdistance the predator. It's the predator which can choose whether they want to outrun the prey in the short term or the long term.

That Lieberman is out of shape and therefore not a good example of a functional running body type? Aside from being a useless ad-hominem attack, the dude actually lived with the fucking Bushmen and went on persistence hunts.

That a dude who ran down an antelope for five hours would be too tired to stab it to death? Please. A modern Ironman athlete in Kona can bike a hundred fucking miles and still have enough energy to run a marathon through a lava field. They could stab an exhausted animal.

That there's simply not enough payoff for running down an animal? It takes, at most 3000 calories to run a marathon. A small male Kudu (African antelope) is about 260lbs, and even if if only yielded 100lbs of meat that would be roughly 100000 calories, not including marrow and organ meats. Yeah, a 33:1 payoff isn't worth it... ok...

What arguments exactly did you find compelling? I can't pull up his page at work, so I'm going on memory here.

tightWeekly · 2012-05-25T15:59:01.237483+00:00

I'll tell you what... summarize his argument and the evidence which you find compelling for me and we can have a civil discussion about it here.

finkicare · 2012-05-25T15:53:27.868949+00:00

I'M FAT BECAUSE MY BODY VIOLATES THE LAWS OF THERMODYNAMICS!

tightWeekly · 2012-05-25T15:50:26.713849+00:00

damn. really? and all of his reference at the bottom?

Most of his references at the bottom don't say what he thinks they do.

also, you failed to mention anything about all the other links.

I wasn't concerned with the other links. The Chaos and Pain ones were retarded.

so i presented a differing opinion and that's a bad thing? sometimes redditors are just angry ppl. who DV things they disagree w/.

People downvote things that are stupid/misinformation/poorly constructed. The Chaos and Pain links are all of the above.

aristo-crat · 2012-05-25T14:14:03.121275+00:00

I get occasionally mistaken for gay from time to time, though it's not usually used in a pejorative sense. It's part of what happens when you dress well and care for your appearance.

Some things that help:

Grow facial hair (may not be an option with your modeling job)
Let your hair be messier
Contrast your appearance and mannerisms. If your appearance is very neat and well kept (like in that picture), let your mannerisms and body language be more crude and less precise. Sit more sloppily, lean, take up more space. That helps a lot more than you would think.
If you spend a lot of time with gay men, you may be picking up some inadvertent habits that they have, in posture, presentation, and gestures. Make sure that's not the case.

Basically, you can change your appearance and style of dress a bit to help, but minor changes to your behavior and mannerisms will go a lot further. They will also let you keep dressing well without being perceived as gay, which is a plus if you're interested in women.

ronversation · 2012-05-25T12:48:03.853389+00:00

Black Tie Optional

Here's a fascinating tidbit. For an event where the dress code is "Black Tie Optional", it is considered appropriate for guests to be wearing either a tuxedo, or a well fitted black suit. We all (mostly) know that.

However, this doesn't mean that you can look into your closet and pick whichever one you feel like wearing that night.

The purpose of "Black Tie Optional" is not to make the event more casual, but to allow guests who do not have the means of owning a proper tuxedo the ability to attend.

The rule is this: if you own a tuxedo or clearly have the means to own a tuxedo, you are expected to either show up in a tuxedo or to politely decline the invitation. If you do not have the means to own a tuxedo, it is considered proper for you to show up in a black suit.

And of course, it is always considered more tasteful to wear a black suit than a rental tux.

The more you know.

tightWeekly · 2012-05-25T11:40:31.440789+00:00

Two comments ago you posted this:

Re bone density, everything I've read says exactly the opposite and that long distance running causes density loss.

Then, you post an article that's title is this:

Long-Distance Runners Risk Bone Loss

You can see the difference, right?

Look, here's another article about running and bone health. Go to page 3 and there's a researcher who has worked on this problem for a quarter of a century. Here's what he has to say about it:

Poor nutritional habits, weight restriction to improve performance, and reductions in hormonal levels (similar to the loss of estrogen in women) contribute to male runners developing the disease,

Anywhere from 50 to 80 percent of the cause comes from genetics, either having a close relative with the disease or suffering from a genetic disorder that predisposes you to the condition. We frequently see male runners who have no genetic factors at all develop osteoporosis, but they don’t take in enough dairy products or protein, and they often severely restrict their food intake to keep their weight low. We’re discovering that the combination of hard exercise, reduced food intake, and low body fat can cause a reduction in gonad function, which reduces testosterone levels, leading to thinning bones, similar to the loss of bone density in post-menopausal women.

The TL,DR: Most of it is genetics. The rest of it is explained by ultra-competitive athletes not eating enough, trying to keep their weight down for every edge in competition, even at the expense of their own health.

That's not "running causes bone loss", it's "people being ultra-competitive idiots causes bone loss."

tightWeekly · 2012-05-24T21:44:45.453654+00:00

Those Chaos & Pain articles are so ridiculously fucking stupid that I can't even think of an appropriate insult for that steaming pile of shit the author vomited upon the net.

It's like bro-science meets barely-literate-author meets wishful thinking in a shitty version of a Cracked.com but without the research or humor.

His whole argument basically consists of "people weren't meant to run because I've never heard of this before, also I don't like to run, also I can't understand science, endurance distances make me tired."

I could tear apart every single argument he's made, if I could find one coherent enough to even bother.

Your links are bad and you should feel bad.

tightWeekly · 2012-05-24T21:01:58.412878+00:00

Such as?

Fish? Possible with spearfishing and certain traps, but the rivers in sub-Saharan Africa vary considerably.

Small game/birds? Possible, since a ranged weapon can be something like a rock or a heavy stick. The problem is that small game is small, and you'd get a lot more food scavenging or foraging.

Most of the meat in interior Africa is in large quadrupeds. By large, I mean small antelope sized and bigger. Living in a world with fast predators means that the meat moves quickly. If you're trying to feed a tribe and you can't take down a kudu, you're probably better off foraging or scavenging from a time investment/payoff perspective than hunting small game.

tightWeekly · 2012-05-24T18:31:42.133783+00:00

I don't know about "often." One guy with a particular point to make about running shoes wrote a book about one present day tribe that does this in a fairly inhospitable ecosystem, and then extrapolated from there on the grounds that they are a "primitive" culture to say "our ancestors" hunted this way.

No, one guy writing a book about running pulled some ideas from several peer reviewed articles, one of which was published in Nature, about persistence hunting and its relevance to human evolution and bipedalism.

Just because you only heard about it from a book about running shoes doesn't mean that author made it up on the spot.

Maybe some did. Maybe others hung on a ledge above the popular watering hole with big-ass rocks and dropped them on thirsty deer.

Not likely.

There's pretty well recognized gap between what people think early humans did in terms of hunting and what human physiology was actually capable of prior to the advent of ranged weapons. So unless you think there was a convenient ledge located exactly above every hundred meter long "watering hole" and that animals lined up in that one spot to get a drink... well some things start to not add up.

The bottom line is that a human being just doesn't have the physical capability to get close to a large quadruped animal. You can't sprint and catch an animal that can run 40 to 50mph and stab it with a spear.

At this point there are really only two possible explanations: either early humans were primarily scavengers and not hunters at all, or we were persistence hunters.

tightWeekly · 1 day

According to that study, though, they still live longer than the average person.

MachineHeart · 1 day

7-8 minutes is pretty low for cardio. You're not going to be burning much (if any) fat doing that.

What you're trying to do is run on aerobic metabolism, which will primarily burn fat and glycogen as a fuel source.

As a beginner, you need to be pushing your cardio sessions past 30 minutes to reliably burn fat. Aim for 45 minutes to an hour. If you can't maintain it for that long lower the intensity or change the exercise. If you're a big guy, running may be pretty rough on your joints, try a stationary bike or the elliptical.

If you're only going to be doing 7-8 minutes of cardio at a time, you might as well not bother.

MachineHeart · 1 day

Be careful to limit your cardio to 45 min or less, otherwise you will risk using your muscles as energy instead of fat!

Your post is pretty good, but this part is misleading. It would take a LOT of energy burn to begin muscle proteolysis.

This study looked at 60 minute strenuous aerobic workouts in healthy males and found no increase in muscle proteolysis.

The aerobic metabolic systems run primarily on fat. When you start strenuous aerobic exercise your body will burn both fatty acids released into the blood by your fat cells and stored glycogen in your muscles and liver. Since your brain can't run on fatty acids, though, as your glycogen stores begin to get low your body will start fabricated glucose from lactic acid and some amino acids that float around in your blood. The ammonia smell that results is a sign of amino acid breakdown, which causes some people to incorrectly believe their body is catabolizing muscle.

tightWeekly · 1 day

also, youd be hard pressed to find anyone in this subreddit that thinks that distance running is better you. apparently the only form of exercise that anyone should be doing at any time is squatting heavy weights.

True story.

Unfortunately for them, the peer reviewed science points in the other direction.

tightWeekly · 1 day

Here are two articles:

Mortality and longevity of elite athletes, which finds that elite endurance athletes and mixed sport athletes live longer than the general population.

Increased life expectancy of world class male athletes found that endurance athletes on average lived longer than power athletes, and both groups lived longer than the general population.

Lastly, I noticed in another comment you posted that you wonder if the benefits of distance running are really there compared to walking.

There's a lot of modern belief that strenuous exercise will make you die young and moderate exercise is what really improves life expectancy. I think the above two studies clearly present some strong evidence to the contrary, but here's another article (an editorial correspondence) in the British Journal of Sports Medicine that reviews some of the literature: Strenuous endurance exercise improves life expectancy: it's in our genes

elmonstro12345 · 1 day

Source for that? The torque generated by a disc brake is enormous, and I remember reading that most consumer cars will have roughly 10x the braking power as the engine's peak horsepower.

terifficwhistler · 2 days

Never shot one... but I want one so bad.

cooliobean · 2 days

Wooooosh...

terifficwhistler · 2 days

I like pumps because they're simple and they almost always work.

Semi-autos, have, in my experience been finicky. With the right loads and a lot of testing you can work out any cycling issues, but it still makes me nervous.

Plus, people have a tendency to dump the contents of the magazine when shooting under stress. A pump is a bit slower, though still plenty fast and deliberate.

That being said, my nightstand gun is a short recoil operated 9mm handgun.

Just my two cents.

j_sciessere · 2 days

If you're racing and it takes two seconds to shift you're screwed.

Yah. Although ironically you'd be screwed on the straights, not in the turns.

The traction limit, which if i'm understanding correctly basically dictates how much it takes before the car loses traction, for drift cars is very low in the rear, and the car will spin out trying to take the turn normally, and it would have to go at a much slower speed than if it were to drift, isn't that right?

If the car spins out it's past the traction peak. That magical drifty goodness is basically a controlled spin-out, though. A car set up to drift will turn fastest just before the tires break free. It will look stupid doing it, but it will be faster.

Also, you sure love the millikens.

Aerodynamicist turned racecar driver turned father of modern vehicle dynamics. Not much to not like about the dude.

That and I'm screwed, you've dropped the notorious "defensive" bomb.

Hey, you were the one who kept asking me what I had against drifting. I never said anything bad about it, only that it's not the fastest way around a corner.

j_sciessere · 2 days

That's pretty cool, I didn't know that.

You're right then, a tarmac WRC stage would probably be the best demonstrator of a similar car going the fastest way around a turn.

j_sciessere · 2 days

Things is... prove this, you can't. That's why this debate still exists. Saying it's "simple vehicle dynamics" doesn't make it "simple vehicle dynamics."

[...] Something else I might add, this is all on the premise that having traction is the fastest way to navigate a turn. This is a statement that isn't proven one way or the other.

These two are related.

Yes, it is simple vehicle dynamics, and yes I can prove it.
Yes, it is... because what you have to understand is that traction is what makes a car move at all.

The basic fundamental concept of modern vehicle dynamics, as pioneered by W.F. Milliken and his son Doug Milliken, is that all forces which act on a car (aero aside) act on it through the tires.

Acceleration, braking, and turning, all can only happen via the car pushing on the car through the tire contact patches. This is traction, and thus, TRACTION becomes the basic currency and limiting factor for making a car change direction and speed.

If you look at the data from a 6DOF tire testing machine, you will see that there is a traction peak, after which additional forces on the contact patch cause the tire to lose traction. This peak can be passed by overloading the tire via braking (locking the brakes & skidding), turning too sharply (understeer or oversteer out of a turn), or via the engine (spinning the drive wheels).

The mathematically fastest way to get a car from one dynamic state to another is at the traction limit, since the traction limit is the limit of rate of change in a wheeled vehicle system. The fastest way to get a car at 100mph to 0mph is by braking at the traction limit. The fastest way to get a car from 0mph to 100mph is by accelerating at the traction limit. The fastest way to get around a turn is at the traction limit.

This is like saying the fastest way to move information in the universe is at the speed of light. It's a simple fundamental principle of the physics involved.

Thus, drifting, in which a driver deliberately exceeds the traction peak (causing traction to drop) cannot be as fast as driving in a manner that maintains the maximum traction.

If that doesn't make sense to you... I really don't know what else to tell you, other than to recommend you pick up a Carol Smith book, or Race Car Vehicle Dynamics by the Millikens.

That's why this:

It doesn't just slide, because of lack of traction, it also pushes laterally. You're wrong about the power that makes it to the ground. Simple as that, it does matter. If you're in the power band, and you have traction, that torque and horsepower gets to the ground.

... is a misunderstanding of the physics involved. The car slides because of a lack of traction. Torque gets to the ground through traction. When the wheels have broken free and are spinning you are past the traction peak, and therefore do not have as much traction as you could have. You cannot push on the ground more than you have traction any more than you can reach your arm out farther than your bones will let you. Traction is pushing on the ground the same way that your bones are the length of your arm.

You approach the right hand turn, release the clutch, break, rev to ~6000 rpm. Release break at apex, rev match 3rd gear to 5000 rpm. 280 hp 300 ft/lbs to wheels. You approach the right hand turn, release the clutch, break, release break at apex, put in third, gas pedal down, clutch up, and now you're at 3000 rpm. Much less that 280 hp 300 ft/lbs are making it to the wheels. While both of the cars took the first half of the turn the same (pre apex) at the apex, the first scenario will have a much faster second half of the turn than the first. MUCH. So yes, so much is wasted there. Shifting technique matters, even if timed the same/perfectly/whatever. Say otherwise, and I'd have to question if you've ever driven a manual or looked at a torque/hp map.

Not only have I driven a manual, looked at a torque/hp map, studied tire load/traction curves, and done kinematic suspension analysis... but I've driven an open wheeled racecar, rigged one up with wheelspeed sensors and shock pots, and helped tune suspension setups based on the collected data.

Your example is a strawman. A botched shift is a botched shift. It's the SPEED of the shift that doesn't matter in the turn, which is what I was referring to.

The SPEED of the shift is irrelevant because there is a large portion of time during which you cannot be accelerating, because braking and turning are consuming all available traction. When this period of time is over, that's when you need to get on the throttle. If it takes you two seconds to shift, you can start shifting two seconds earlier. There's a big window of time.

It's on the straights that the speed of shift matters, not the turns.

I don't know what you're gripe is with drifters, but that shit is fast, and the reaction times need to be faster, and the amount of control needed is ridiculous. It's not just an "aesthetic" sport that just anyone is good at. Like any other form of racing, it takes an enormous amount of skill.

Yes, it's a fast sport. It's not fast compared to what the same cars could be doing in lap times if they were carving. That's not the point. I have no gripe with drifters, the original question was "is drifting the fastest way around a corner?" The answer is no, it is not, because that is not the point.

Your TLDR is accurate if you are driving a car that isn't meant to drift. I'm no professional drifter, nor am I an amateur drifter. Hell I don't even race, other than smoking the occasional hotted up Mustang GT (no match for the SRT mustangs if it's not light to light).

My TLDR is accurate for all cars. The fastest way around a corner is at the traction limit, this is again a basic principle of physics. Drifting is not about the fastest way around the corner, so while my TLDR is still accurate, it's not relevant to drifting.

I'm just a student with a 2011 r c30 that's getting its brand spankin new [1] GT3071R turbo kit installed, with a 25mm rear sway bar, slotted 300 mm rotors, and a RICA softloader tune. I also love driving it. I also love cars, clearly you do too. Just ease of the drift-hate. Gets me riled up. It's just as valid a form of driving as the next. And while you haven't said otherwise, it sure feels like you are.

That's fine dude. I'm a mechanical engineer with a graduate degree who has formally studied vehicle dynamics.

Drifting is fine, I don't know why you're getting defensive. It's just not the fastest way around a corner, and I think it has enough merits on its on that there's no reason to pretend it is.

j_sciessere · 2 days

No... that's not at all how it works. You cannot use [1] this to drift well (too sticky, you'll never slide unless you're on gravel or something), but you can use it to race very well on pristine track. There are completely different camber, toe angle, ride height, limited slip, weight distribution (big one), the handbrake, material, etc. and I'm willing to bet the torque/hp maps are extremely different between the same base models:

Look, I'm with you that a car set up to drift is very different than a car set up to road race. But look at the steady state equations of motion for a vehicle in a turn. The optimum line that a vehicle takes through a turn (this is the question that was asked) will be pretty much the same, regardless of setup. The tire composition, temperature, loading, and angle that it is presented to the road by the suspension mid-turn will determine the overall traction, and the overall traction will determine the speed at which the driver can go through the optimal line of the turn. But the line will be roughly the same.

Also, it's ABS not TCS that maintains the slip ratio.

Only while the car is slowing down. Traction control maintains slip ratio through acceleration, either by active braking, or via ignition/fuel cutoff.

Furthermore, traction control WILL change the dynamics of a turn, especially without a limited slip differential, because with no traction control, the car will let the inner wheel lose traction and spin faster than the speed at which it's moving, which may or may not be bad.

That's more of an issue of the diff than traction control. It's the diff that allows the drive wheels to spin at different rates, not TCS (depending on its implementation).

As per which one's faster, it depends on the driver, and the severity of the turn, and the amount of straights. To put it in extremes, you ask a the driver of a drift car to do go straight for a mile, turn around a cone and come back, and the driver of the same car, but tuned for turning not drifting, likely the drifter will be back sooner. However, you make that straightway 20 miles, and keep the cone, the drifter will lose (the excessive camber will affect straight line acceleration).

No car set up to drift will drift through a turn faster than a similar car set up for optimal turning will carve through a turn. That's simple vehicle dynamics.

Also, drift cars stay in gear, and (ideally) in their optimal powerband throughout the turn.

Yes, but it doesn't matter, because only a very small portion of that power is getting to the ground. The engine is not the limiting factor in a turn: the tires are, and a drifter is spinning them far past the optimal slip ratio. In fact, drifting requires this spinning, because the drop in traction that comes from spinning is what allows the car to slide in such an aesthetically pleasing way.

Taking a turn the regular way, no matter which technique you use, double-clutch, feathering, heel-toe, to keep those revs up, you've still gotta put it back in gear which will knock your rpms below your powerband briefly.

If I could draw the force vector on a tire contact patch of a car going through a turn, it would start pointing backwards (as the car begins to brake entering the turn), and then it would rotate to the inside of the turn as the car enters the steepest part of the line, and rotates forward as the car accelerates out of the turn. If the driver were perfect, the length of the vector would stay roughly the same through the turn, and only the direction would change. The length of this vector would correspond perfectly with the overall traction that tire was capable of under that temperature and loading.

A skilled driver is able to change the direction of that vector while keeping the magnitude the same by switching smoothly from brakes to wheel to throttle. This is the concept of a "traction circle". In the perfect execution, the tire's traction is maxed out through all parts of the turn... nothing is wasted, and the car moves through the turn as fast as is mathematically possible.

Thus, the shifting technique in a turn isn't important so long as it is timed correctly, because for a large part of the turn the tire's traction is maxed out with braking and then turning. As long as the car is in gear before the contact patch force vector needs to rotate forward, nothing is wasted, and nothing is lost.

Drifting's artistic, loud, gorgeous, reckless, stylish, stupid and fast.

Drifting is stylish. Drifting is beautiful. Drifting feels fast, but drifting is not fast, and wasn't meant to be.

TLDR: the suspension and tires determine the traction availible to a car in a turn. The line/path of the turn is selected to minimize the traction required by the turn. The more traction you can get from the wheels, and the less traction you need from the line, the faster you can go.

j_sciessere · 2 days

Completely different cars, tires, suspension setup, traction control, surface and circumstances.

As far as the line and the lack of sliding sideways, there isn't going to be much difference. Traction control won't change the dynamics of the turn, it just helps the driver maintain the optimum slip ratio.

The biggest change will be where the drivers start braking and how fast they can take the turn.

If you want to see what the fastest way around a corner looks like in a more comparative sense, try WRC.

I disagree. Rally is on dirt, this video was on asphalt (mostly). Vehicle dynamics on asphalt have been pretty well understood since William F. Milliken developed the automotive equations of motion and the first 6-DOF tire testing machines. Vehicle dynamics on dirt are a whole different ball game, and some limited but visible amount of sliding seems to make the split times faster. That's not the case on asphalt.

Maybe a better comparison would be the SCCA Nationals, or the better drivers in a club race.

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