didn't see compression in top NYC Marathon runners (Page 3)

That analogy doesn't fit because they are both going the same distance. We are talking about two people running for 2.5 hrs. One covers 26 miles, the other 16. They each put out the same amount of effort/work regardless of fitness.

Like I said, this doesn't have much to do with anything, especially those dorky-looking compression socks Seriously, if they were stripped like Salami and the rest of the Carver High School basketball team's socks on the White Shadow, I would maybe wear them.

In people with superficial venous insufficiency (reflux) compression stockings improve circulation. I doubt people with normal circulation have much benefit.

No.  The amount of work required is a function of force(moving your weight, overcoming friction) and distance.  Time doesn't enter into it.  

It does though. We are talking about two people asked to run at certain effort for 2.5 hours. The same amount of force over that set time moves one person (lighter, more efficient, etc.) 26 miles, but moves the other (heavier, less efficient) only 16 miles. Same amount of work, though, right?

...curse you high school physics...

If the "amateur" weighs 26/16ths of what the pro weighs, then you are correct.  

However, "time" still has no effect on work.  Force times distance.... that's all.

Quantitatively?  No.  Qualitatively?  Absolutely.

makes sense. thanks. i appreciate it.

You may want to revisit your equations; work is not force times distance, it is force dot distance which is very different.

Shane

I'll see your dot product, and raise you:

"Distance" is a scalar, and cannot participate in a dot product.

Work is Force dot Displacement.

lol, this thread is going to get shoved into CoJ before too long!

Good catch - must proofread a little more closely I guess.

However, the dot product invalidates your 26/16 analysis as weight plays only a minor role in the amount of work that is done in running.

Shane

Oww...brain hurts................

At the risk of being labeled a sexist ***, I have to say that Desiree Ficker (far right) is one of the few endurance athletes who looks fabulous in the race - even better than her non-racing pictures. (I certainly look like garbage in my race pics - suffering too much!)

Ok back to regular programming. 

Is it weight, or mass that is important?  What about the additional drag with the bigger athlete?  What about aero visors?

Physics is only one component of physiology. In physiology you have to take efficiency into account as well.
Hold two 20 pound dumbells out in front of you without letting them drop. How long can you hold them? You shouldn't get tired because if they arent moving you aren't doing any work, right? Holding those dumbbells up takes muscular effort which doesn't result in any forward progress or measurable work output (the physics of the equation), but it's consuming energy/calories to keep them there. So it's a very inefficient exercise.

running on the otherhand does produce forward movement, which can be measured in workoutput. (or on a bike, you can measure the power out put) The part of the equation that we cannot see is how much work the athlete is putting into the effort and what the relationship is between the two. (work input and work output) Pros are much more efficient because of their training loads, so for a pro to run the same distance as an amateur, they are using less work input for the same work output.

Cycling is one of the most efficient exercises, and a good cyclist is about 25% efficient. 25% of the work that goes into the bike results in forward movement. The rest is lost as heat. Swimming is a great example of this. Average swimmers are about 3% efficient...only 3% of their energy used to swim goes into forward movement. (No wonder I'm so slow!). Michael Phelps is about 9% efficient! So not only can he put more work INTO his swimming effort (because of his general conditioning), but he gets much more work out of it as well.

I don't know the %ages of running off the top of my head, but it's likely somewhere in the 20% range

As far as distance and recovery, pro marathoners run upwards of 150 miles per week. Their conditioning allows them to push hard and recover easily, and feel great after training loads that would make most of us crumble. So if I sent out Meb and an average Joe here from BT on a 2 1/2 hour running time trial tomorrow, who will feel better on Sunday? Who will get up and feel ready to run again, or even go out and run more a few hours after the time trial, you know, as a "cool down" run? THe BTer probably didn't cover as much ground, and possibly didn't use as much energy input...but they are less efficient then the pro, do not ahve as big of a training base over the years and recent training is probably 1/5th or less of what the pro marathoner is doing.

Not sure if anyone really cares at this point anymore, but if you are going to use the physics analogy to bicker over (not you pshorty, others here), then you need to get the work input part of the equation sorted out as well.

JSNRLOL

This was early on in the race.  There is still a noticeable pack.  By mile 20 there were only around 5 of them together.

What is funny is that Paula and Desiree are both in that 5'-4" - 5'-6" range and they absolutely TOWER over the other women in the field!  I noticed that at the US Olympic qualifier last year in Boston where Desiree was like a head taller than everyone else.

Radcliff is 5'8" and  Ficker is 5'7"

maybe has more to do with what their sponsors want to market lately?

So I was 1 - 2" off .... sue me.

They are still 8" + taller than everyone else in the lead pack.

Sorry but that pic makes them look huge. Tulu, on Radcliff's right is 5'3".