If Kipchoge's 2:00:26 dosen't count as any sort of record; does it count as a personal record?

Each person gets to decide what they count as their PR. Ry Guy Hall probably considers his wind tunnel Boston as his 'thon PR.

Every other Olympic running distance is run on a bouncy track and no one says a thing, but if somone runs a marathon this way it doesn't count? That makes no sense. As long as there is no net downhill it's a record. If you think otherwise then Bekele and El Guerrouj are no world record holders.

KarlMarxist wrote:

to increase stiffness and provide a propulsion sensation.

See how careful they are not to get sued for false advertising?

The shoes had nothing to do with it. Just the pacers, steady draft from a vehicle and other support.

Yea but all the runners run on the same "bouncy" track. No one says a thing because there aren't people still running on cinder tracks anymore.

You added a second to his time.

I'd count it as a PR. People have used those shoes in other races legally. The only non-legal thing done was rotating in fresh pacers. You and I could have pacers all the way to the finish because we aren't as fast. That means his only non-legal advantage is an advantage that almost all the rest of us already can have.

Covered the distance on his own two feet counts as a PR. Official World Records? Well I guess that's for the rule makers to decide to keep things official and legit.

Positive Contribution wrote:

Covered the distance on his own two feet counts as a PR. Official World Records? Well I guess that's for the rule makers to decide to keep things official and legit.

Exactly this. It's actually hasn't even been that long since the IAAF refused to keep official marathon records at all, since all courses are different.

I think Kipchoge is sophisticated enough to accept both that he doesn't have the "by the book" record, and also that he has run the fastest marathon in human history.

sure as long as it can be marked as done with a serious wind-block and other technical assistance like the shoes

if Paula's WR was changed to a "worlds best" and then moved into it's own unique category to be called a WR again, I am fine with this effort being called a technically-assisted world's best

ddfun wrote:

Each person gets to decide what they count as their PR.

Exactly! Paul Ryan decided that his marathon PR was two hour and fifty-something. Who are we to challenge that?

zzzz wrote:

You added a second to his time.

I'd count it as a PR. People have used those shoes in other races legally. The only non-legal thing done was rotating in fresh pacers. You and I could have pacers all the way to the finish because we aren't as fast. That means his only non-legal advantage is an advantage that almost all the rest of us already can have.

And a personal Tesla with a 4m^2 board on the roof driving a couple of meters in front?

If someone told me they broke 3 hours for the marathon following a van the whole way I would call it a farce. It's similar to taking a PR from a treadmill run in the gym.

Blabla1 wrote:

Every other Olympic running distance is run on a bouncy track and no one says a thing, but if somone runs a marathon this way it doesn't count? That makes no sense. As long as there is no net downhill it's a record. If you think otherwise then Bekele and El Guerrouj are no world record holders.

What is a "bouncy" track? And why are they running every other Olympic distance on it?

Nikolai wrote:

zzzz wrote:

You added a second to his time.

I'd count it as a PR. People have used those shoes in other races legally. The only non-legal thing done was rotating in fresh pacers. You and I could have pacers all the way to the finish because we aren't as fast. That means his only non-legal advantage is an advantage that almost all the rest of us already can have.

And a personal Tesla with a 4m^2 board on the roof driving a couple of meters in front?

My impression is that the Tesla was too far ahead to provide any advantage at the speed they were going. This is based in part on experience on a bike at much higher speeds, having drafted behind things like trucks, buses, and so on when I was young. Maybe some aerodynamics experts can weigh in.

they mean a high-energy-return mondo track like they used in Rio and London

our D1 has the previous generation technology mondo used and I set PRs every time I run on it vs the road, it's fast as hell

the reason they didn't use a track for this of course is they don't sell track, they sell shoes

NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO, not a PR.

You are like the microdick guys who run a huge downhill 5K an count it as "PR".

zzzz wrote:

Nikolai wrote:

And a personal Tesla with a 4m^2 board on the roof driving a couple of meters in front?

My impression is that the Tesla was too far ahead to provide any advantage at the speed they were going. This is based in part on experience on a bike at much higher speeds, having drafted behind things like trucks, buses, and so on when I was young. Maybe some aerodynamics experts can weigh in.

That Tesla cuts the wind significantly, which the formation of pacers then ran into, causing a further increase in drafting effect.

Believe me, those 3 minutes were cut from the car and bodies, not the shoes. Nike were so confident because they could test their theory in a wind tunnel easily. All they needed was for kipchoge to maintain 2:02:xx effort.

As I (and others) suspected.

http://www.runnersworld.com/sweat-science/does-drafting-help-in-running

At marathon pace (here it is 5:22 pace per mile), over 2% of the total energy costs is in overcoming air resistance, on a still day. Kipchoge was running closer to 4:35 pace, which is actually more like 3% according to those figures.

Running at 4:30 pace 1 meter behind one single man saves 80% of this energy cost. That's significant. I wonder how much a bunch of guys and a car right in front saves, maybe 90%?

So with in excess of 2.5% of the total energy cost being saved from slip streaming, Kip didn't need the shoes.

Nikolai wrote:

zzzz wrote:

My impression is that the Tesla was too far ahead to provide any advantage at the speed they were going. This is based in part on experience on a bike at much higher speeds, having drafted behind things like trucks, buses, and so on when I was young. Maybe some aerodynamics experts can weigh in.

That Tesla cuts the wind significantly, which the formation of pacers then ran into, causing a further increase in drafting effect.

Believe me, those 3 minutes were cut from the car and bodies, not the shoes. Nike were so confident because they could test their theory in a wind tunnel easily. All they needed was for kipchoge to maintain 2:02:xx effort.

Adding the benefit of the Tesla to the pacers to the benefit to Kipchoge doesn't make sense. This isn't like a chain of NASCAR cars. That Tesla is too far ahead to benefit Kipchoge. I'm not even sure the Tesla benefited the front pacer much.

I drove cross country three times last year in my Prius. That left me plenty of time to experiment with hypermiling and a bit of drafting (though I never go so close to be tailgating). I'd watch the effect of distance behind a big rig on the instantaneous miles per gallon, and realized at even at 65 mph, you don't get much of a draft behind a big rig unless you get too close for my comfort. At 13 mph, the effect is much shorter because drag goes up by the square of speed. The turbulent air behind the draftable distance of low pressure behind the truck also quickly ruins the effect. You guys with bikes with power meters could do testing too behind a friend driving a truck at 13 mph. I doubt there would any power savings at the distance Kipchoge was behind the Tesla.

Riders at the back of a peleton save up to 40% riding at 40km/h so I'm not sure what kind of truck you were following. The savings in marathon running are way, way smaller but a 2%+ in energy savings is huge. That is drafting behind one other runner. Could be as much as 2 minutes across a marathon.

The physics is posted there, it has been tested properly using science. Your personal experience doesn't really count for much here I'm afraid.

And for the record, the Tesla car shielding the runners who in turn shield kipchoge works exactly as you said it doesn't. The vortexes coming off the back of that car with the windbreak on its roof will collide with the pacers who create another low pressure zone that remains turbulent, rather than the air returning to a laminar flow.