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Saturday, August 16, 2008

Beijing 2008: Men 100m report

9.69 seconds - World Record

For RACE ANALYSIS, including split times, and average speeds for Usain Bolt's world record: Click HERE

Usain Bolt delivered. Nobody else stood a chance. It was quite simply the most devastating display of 100m sprinting I have ever seen. The "race" that everyone (including us) had predicted never materialised - Bolt was just too good (and Powell bad, it has to be said).

The world record in the 100m is always a special occasion. When it comes on the biggest stage in world sport, the Olympic Games, it's that much more spectacular. And it does not get much more spectacular than the sight of a man destroying the next seven fastest men in the world, celebrating about 20m from the finish line, pumping his fist against his chest with 10 m still to go, and still breaking the world record by 0.03 seconds. Truly incredible.

A race of surprises...except for the world record

The only thing about this race that was NOT surprsing was that the world record was broken. Everything else was something of a shock. Those shocks began in the semi-final, when Tyson Gay, the world champion from the USA failed to qualify after finishing fifth in his heat. That meant that the much-anticipated showdown between the three giants of world sprinting - Bolt, Asafa Powell and Gay - failed to materialize (it also made something of a mockery of my earlier pre-race prediction, which was done BEFORE the semi-final! I'm going to claim that at least I picked the winner, and almost got the winning time right too...!)

In any event, Gay's presence in the final would hardly have made a difference, so dominant was Bolt. But it is a great shame that he hurt himself in the US trials, because perhaps he might have pushed Bolt a little harder and we'd have seen a 9.65s time, so comfortable was the Jamaican in the absence of any rivals in this race.

Powell fails - slower in the final than the semi

The next big surprise was the failure of Asafa Powell to deliver in the final. The big Jamaican, who had beaten Bolt earlier this year, was completely unable to raise his game when it mattered, and finished a very disappointing fifth place. His time in the final? 9.95 seconds. His time in the evening's earlier semi-final? 9.91 seconds. Which means that, for the second big championships in a row, he actually ran a slower race in the final than in a qualifying heat. That performance will serve only to re-inforce the perception that Powell is not a big-race runner. Last year, we mentioned the word "choker", which is a little harsh, of course, but Powell has tried for the past year to shake that particular title. Tonight, he failed, and the title fits a little better. On second thought, perhaps his performance wasn't such a surprise, after all...

Thanks to Powell's disappointing run, the minor medals were won by Richard Thompson of Trinidad and Tobago (silver in 9.89 s) and Walter Dix of the USA (9.91 s for bronze), which was the third big surprise. Both are PB's, which is as much as one could ask in a big final like this. Fourth went to Churandy Martina of Netherlands Antilles, in a national record, which would have been their first medal - 0.02 seconds denied them that glory.

Bolt - the star of the show, a magnificent performance

But the star of the show was Bolt. The race was expected to be close, fast and exciting. It was two of the three, but "close" is not a word that fits this final. In fact, the much anticipated "race" never materialised, thanks in part to Gay's semi-final exit and Powell's "no-show". But the main reason was that Bolt was ridiculously fast.

His start was, as usual, not particularly spectacular. After about 30 m of running, he was mid-pack, with Thompson in Lane 5 slightly ahead of him. Powell also got off to a good start. But after about 30m, as Bolt's head came up, he took control of the race and the men who up to that point had looked competitive suddenly looked very ordinary.

There cannot be a runner with this kind of acceleration from 30 m in the history of the event. Of course, every generation has runners who are dangerous in the latter half of the race, but Bolt, running 9.69s, moved away from men running 9.89 s and created a 0.2 second lead by the finish line. It was astonishing sprinting.

When the cameras showed the race from the front, you could see Bolt actually glancing across to his right, where he knew the big threats would come from. Bolt virtually ran the 100m Olympic Final as a tactical race - he knew where his rivals were, he created a lead between 30m and 80m, and then he celebrated.

About 20m from the line, his arms dropped to his side. About 10m from the line, he leaned backwards, and gave himself a chest thump with his right hand. He crossed the line and kept running, bouncing all the way to the back straight as the crowd erupted. That celebration cost Bolt some time - who knows how much? Perhaps he was capable of 9.65 seconds had he continued at the same rhythm.

In the end, it didn't matter. Bolt had the time to celebrate mid race, to look natural and easy running 9.69 seconds.

Usain Bolt - a new "breed" of sprinter

Bolt is a different type of sprinter - previous champions, like Maurice Greene have been muscular, powerful, strong men, who burn up the track with the sheer force of their running. Bolt is different - he bounces, flows like water, and looks incredibly easy running faster than anyone else has ever been able to. I would love to see a biomechanics analysis of the race, but for a basic illustration of the difference, consider that Bolt took 41 steps to run the race; everyone else took 44 steps.

What is the physiology that underlies this advantage? Very difficult to say...explosive muscles, certainly. Muscle power, yes. But there's something there that no scientist can measure. I believe the big difference is neurological. It is the ability of the brain/central nervous system to control and co-ordinate the muscles, creating the spring. There is something called the stretch-shortening cycle, where energy that is stored on landing is harnessed during the push-off phase, so that the muscle-tendon unit acts like a spring.

It's possible to measure this stretch-shortening cycle activity, but not during sprinting like this. I believe (and this is a bald assertion, admittedly) that what sets Bolt apart is his muscle tendon unit, and the ability of the brain to co-ordinate the timing and sequence of muscle activation. Science can't measure this, but the next time you see a repeat of this race, watch Bolt compared to the men either side of him, and you can see it. And so just watching Bolt allows us to appreciate what it takes to be the world's fastest man.

In all of 9.69 seconds.



Anonymous said...

Does anyone know, how fast did he actually run (in km/h)? And what about the 10 m splits?

Ross Tucker and Jonathan Dugas said...

Too early to know. I suspect that in the next few days, maybe weeks, that info will be revealed, if at all. But for now, that detail is beyond us...

If it does come out, we'll put it up!


david said...

Hi Ross, Bolt's reaction time was the 2nd slowest in the race. Your take on that and WR progression over last 40 years:
9.69 U Bolt, Beijing 2008
9.72 U Bolt, New York 2008
9.74 A Powell, Rieti 2007
9.77 A Powell, Athens 2005
9.79 M Greene, Athens 1999
9.84 D Bailey, Atlanta 1996
9.85 L Burrell, Lausanne 1994
9.86 C Lewis, Tokyo 1991
9.90 L Burrell, New York 1991
9.92 C Lewis, Seoul 1988
9.93 C Smith, Colorado 1983
9.95 J Hines, Mexico 1968

what's your prediction for the next 10 years? Well done on a Great site.

david said...

Sorry Ross, I should have identified myself it's DAVE SPENCE

Anonymous said...

Here it is:

RT 0.165 s.
10m 1.85
20m 2.87 (1.02)
30m 3.78 (0.91)
40m 4.65 (0.87)
50m 5.50 (0.85)
60m 6.32 (0.82)
70m 7.14 (0.82)
80m 7.96 (0.82)
90m 8.79 (0.83)
100m 9.69 (0.90)

0.82 equals 43.90 kmh! someone on Track and field forum stated, that he reached over 28 mph (47.4 kmh)...

Seb said...

Found this here:

RT 0.165
10m 1.85
20m 2.87 (1.02)
30m 3.78 (0.91)
40m 4.65 (0.87)
50m 5.50 (0.85)
60m 6.32 (0.82)
70m 7.14 (0.82)
80m 7.96 (0.82)
90m 8.79 (0.83)
100m 9.69 (0.90)

Amazing, how in the 50-80m range, he keeps 12.2m/s average top speed. With a little pushing wind, he probably might break 9.60.

And what about breaking 19s on 200m??

Seb said...

I was just scooped while editing my comment. Damn!

Andrew said...

If the stretch-shortening cycle can explain Bolt's advantage, why doesn't it help him in the first 30m?

I can't wait to see the 200m!

Anonymous said...

I would agree with your rationale that neurological factors (e.g. SSC) are likely at the root of Powell's running prowess. I just recently saw Peter Weyand and Matt Bundle present some research on how sprinters modulate the "stiffness" of their musculo-tendon units during different phases of the sprint cycle. If I remember correctly they suggested that in order to run at high speeds the sprinters need to make effective use of the SSC, which appears to be done by modulating stiffness during the eccentric impact phase.

Anonymous said...

With 41 steps for the race, Usain's step rate was a lofty 254 steps (127 strides) per minute. He covered an average of 4.88 meters per stride. Is his average contact time known?

Ross Tucker and Jonathan Dugas said...

Hi Dave

THanks for the information and the visit, good to hear from you! Trust you are well! Thanks for the compliments on the site too, it's great to hear positive feedback from you especially!

I'm not sure where this world record is headed. As usual, the non-athletics media (and some within the sport) are getting very carried away with their projections. I see Bolt as having maybe another 0.1 seconds in him, and so it's quite conceivable that the record will drop to a 9.59s in the next 2 years. His biggest challenge will be to remain grounded and injury-free, but that's probably going to be his contribution (assuming he is drug-free, of course!).

The event is in a golden age at the moment. After 1996, when Bailey ran 9.84s, there was something of a downturn. Of course, Greene did lower the record a little, but what we've seen in the last 2 years has been remarkable. That's why one has to wonder a little about it...

But anyway, let's remain hopeful for now, and say that by 2020, the record might be 9.55 seconds. There was some research earlier this year out of France that suggested that 9.5 seconds was about the limit, after which time we'd have to resort to measuring times in the 1/1000th of a second. Perhaps that will come sooner than they projected.

Whatever happens, I reckon Bolt is a sub 9.60s man, but this talk of him running 9.5 if he just "tried" is wrong. Our latest post with his 10m times shows that he lost at most 0.09 seconds thanks to his celebrations. More likely it's about 0.05 seconds, and he'd have run 9.64. Taking another 0.05 secs off that, to break 9.60 is a tough, tough ask...


Ross Tucker and Jonathan Dugas said...

Hi Andrew and Seb

Thanks for the feedback on this one. Sorry I'm tardy in replying, but keeping up with the Olympics is a tough ask...! Too many events at once!

Andrew, I think Bolt's starts suffer from his height. He has a pretty tough time getting out the blocks thanks to his higher centre of gravity - the shorter, stocky sprinters are always first away. once into his running, his stride length is extra-ordinary, as seen from the simple calculation provided in this discussion thread.

Seb, thanks for the split times. I've responded to some of your and Andrew's other comments in that thread, so you can check them out there!

Finally, to Educate runner, you'll find that the other guys have even higher stride rates - they took 44 or 45 steps in more or less the same time. So Bolt's advantage is the stride length, which is small, but significant one.

I don't know if anyone has contact times - I'd be very sceptical of the accuracy, because to get good data there you'd have to plan the study carefully and actually be going out to get contact times. Measuring them on TV must create too much error, given how short they'll be. But we'll see, someone might come up with them yet.


Anonymous said...

About the stride length, I noticed on replays how much forward pelvic tilt Usain Bolt used compared to the other sprinters, and how explosive this movement was. Could this be one of the crucial differences (along with his height and limb lengths)?

I also remember vaguely Michael Johnson's much hyped back hyperextension in running 19.32 back in 1996. Might it be a similar situation?


Anonymous said...

"Minor" medals?
Scientific detachment is good but please don't fall into the corperate and mob "gold or nothing" mentality. The extraordinary effort to reach these performance levels deserve more. And even Bolt would not be reaching his speeds without competition.
I thoroughly enjoy your site (wouldn't have bothered writing otherwise). Thanks!


Anonymous said...

Nobody seemes to be awed by the fact that this guy accelerates a 6-5 frame from 0m to 30m just as rapidly as the best sprinters in the world - men who are on average 7inches shorter than he. That to me is phenomenal.Swaggs

Ross Tucker and Jonathan Dugas said...

Hi Mike

Thanks for the mail and for reading the site. Much appreciated.

The term "minor medals" in no way betrays a "mob mentality" towards silver and bronze. I think you've over-interpreting it a little. Fact is, they are the minor medals, that's why the gold medallist stands on the top step of the podium, with the silver and bronze on lower levels. Gold is the major one, the first prize, and the others are not...

So while I agree with you that the silver and bronze are fantastic achievements, the term minor medals doesn't denote any belittling of the achievement - it's just a description of fact. Had I said "only" then it's another story...


Anonymous said...

If Thompson and Dix (the silver and bronze medalists) truly took 44 steps to cover the 100 meters, their stepping rate was about 267 steps per minute - 5-percent higher than Bolt's. But, the distance covered by Thompson and Dix per step was just 2.27 meters - 7-percent shorter than Usain's 2.44 meters. That 2-percent difference (7 minus 5) in effect gave Bolt his 2-percent victory over Thompson (9.69 vs. 9.89).

Anonymous said...

From what I can see in the replays Bolt hit 100 in 41 steps, and the others in 45-46. His stride length is that much longer! However, it is amazing that his turnover is equal to (or faster) than the others when he hits his top speed of 0.82 seconds/10 meter. That is a huge lever to be turning so quickly!

Next: Anyone know how many steps Johnson took in his 19.32? I have been looking at replays and the best I can figure is he needed 44 in the curve and 40 in the straight. The question being can Bolt break it? I think his long stride has got to work against him in the turns.

Anonymous said...

Normally, YES, a long stride can work against you in the curve, but fortunately, Bolt is a 200m Expert and I suspect his coach has informed him that speeding up stride cadence through the corner is key in running a curve fast. Essentially it's the difference between winning Gold and finishing 4th. GO BOLT !

Anonymous said...

The one remarkable stat here is the split time between the 80m-90m segment of the race. Bolt started celebrating 15m from the finish line, and despite that, he lost only a .01 of a second in that 10m segment, recording a .83 after posting 10 meter splits of .82 in three consecutive segments. This tells us that his celebrating did not actually cost him as much as predicted originally in that 5m stretch. His last 10m segment shows a .90. I highly doubt he would have continued a .82/.83 split times in the last segment even if he had run straight through. So the projected 9.59 is slightly a stretch. A 9.65 would be a more accurate projection. That said, he definitely may break 9.60 at some point in his career. It would have to come on a very fast track. His next race at the 100m is next Friday at Zurich supposedly. But that track won't allow a 9.59 unfortunately. It's a fast track. But it's not that fast.

Anonymous said...

One thing that everyone has to understand is that Bolt's 100m time was done with a wind speed of 0.0 m/s. When he ran his first world record of 9.72s it was with a tailwind of 1.7 m/s.

Therefore if he had run his 9.69s race with a tailwind of say 1.7 m/s, then his time could have been approximately 9.64s.

In addition, appart from his slight slowing down at the end which other analysts have approximated at costing him 0.05s, he also made a mistake at the start. In making his second step from the blocks his foot hit the ground (he stubbed his toe!) prior to the completion of the stride. He lost time here. In addition, he had to "recover" from that error. He therefore probably lost more time here too.

In summary, if he had run this same 9.69s race with an error free start, no celebrations and a 1.7 m/s tail wind (remember the legal limit is 2.0 m/s) the time could have been 9.59 or 9.58.

Bear in mind that this is not his best event!

The scientific limits quoted in other comments are way off base.

tim newman said...

interesting point about the 41 steps versus 44 steps.

simplistically that means Bolt turned over at 41/9.69 = 4.23 steps per second.

And Richard Thompson 44/9.89 = 4.45 s/s.

i.e. thompson's was 5.2% faster.

Yet Bolt took 7% less steps to cover the distance.

Strangely enough- using this basic division and the fastest of the 44 step runners, this gives Bolt a 1.8% lead. Or a time of 9.71 seconds.

We know now that Bolt did better than that, at 9.69..and couldve gone low 9.6s.

So the difference beyond stride length and cadence must be the speed generated..and there's an extra 1% there.

I'd be keen to see the bodyweights and bodyfat % of each of the athletes to see who's carrying weight and who isnt...and furthermore, where its being carried (in muscle)


Anonymous said...

I read an article some time ago about the mechanics of 100m sprinting [the reference of which I have lost]. It postulated that essentially the acceleration of the athletes was result of two opposing forces; (1) a forward force applied by the athlete to the ground and (2) an opposing “stopping” force caused by this contact. It seemed to suggest that once the athlete reached a certain velocity, these forces were equalised and consequently the acceleration of the athletes tended to zero. The split times of the world champions seemed to confirm this view. Does any one know of the factors that cause this stopping force.


Michael said...

Prior to Bolt's Berlin run I inadvertently guessed his winning time in that race by amending the result from his win in Bruxelles on the 5th September 2008 to a positive wind assistance reading, approximately +1.0m/s.
9.77 seconds against -1.3m/s wind is approx. equal to 9.58 with +1.0m/s wind.
I have also estimated his best ever 100m time by taking his best 10m splits from Beijing & Berlin, also including what could be his best ever legal start (0.100secs), & then I have taken off 0.01secs for each of his best splits to allow for future improvements, & I have come up with the following times. If the wind were in the range of 0.0m/s to +1.0m/s, the splits would be-

10m 1.79
20m 2.77 (0.98)
30m 3.66 (0.89)
40m 4.50 (0.84)
50m 5.32 (0.82)
60m 6.13 (0.81)
70m 6.93 (0.80)
80m 7.74 (0.81)
90m 8.56 (0.82)
100m 9.38 (0.82)

If the wind were at the maximum +2.0m/s, the splits would be-

10m 1.79
20m 2.76 (0.97)
30m 3.64 (0.88)
40m 4.47 (0.83)
50m 5.28 (0.81)
60m 6.08 (0.80)
70m 6.87 (0.79)
80m 7.67 (0.80)
90m 8.48 (0.81)
100m 9.29 (0.81)

I speculate that although he may never run a 9.29, he will run into the 9.3's electronic.
I say.. watch this space!!!


Michael said...

In an earlier post I suggested a time in the 9.3 electronic range would be possible by Usain Bolt. I now believe this may be somewhat simplifying the whole effort to run a 100 metre race at the optimum on any given day, & with the right conditions, for record purposes. Usain himself has admitted that 9.4 is possible. I just wonder if a time in the 9.3 range would be possible with the right improvements in strength, technique & stamina. N.B. a split of 0.79 secs for 10 metres = 12.66m/s = 45.57km/hr = 28.31mph.