Thursday, August 9, 2012

Am primit acest news letter de la 'stiintificii lumii sportive', iar subjectul m-o trimis cu gandul la prof. Victor Mociani si confratii sai (Coca Florescu +, Dany Popper, inimoasele Arety si Emilia de la Edc. Sport-Turism, C. Vlase, Dinamo s.a.); ei sunt primii care au descifrat+formulat tainele efortului ciclic propriu canotajului academic si apoi, acest val de stiinta sportiva, s-a raspandit, intai la cei de la Caiak/Canoe, apoi la noi la Inot si in mod ciudat - la rusi [ in 1983, la un cantnament comun la altitudine (Tzahkadzor, Armenia, 2000m) 'nacialnicii' au fost intrebati, evident de cine... de mine, 'care este zonarea efortului' etc.; dupa clipa de surprindere, rusii s-au consultat si au promis ca a 2-a zi voi avea intreaga documentatie - asa a si fost, doar ca la cap. explicatii, ei au relatat ca conceptul zonarii efortului il au de la canotorii lor ...., si adaugand, 'aia' l-au luat de la canotorii vostri ... m-am gandit 'adanc'..."ce mica-i lumea" !]
Si iata ca subiectul apare din nou, pe 'tapet', in sarcina specialistilor occidentali, deja in mare fierbere cu tot ce se leaga de JO 2012, Londra.

Dar spre deosebire de graficul oferit de 'stiintificii lumii'....., glumesc..., 'N' la 'noi' este un 'U' asa cum este conceput de scormonitorii efortului ciclic (Mociani, Florescu, Popper) si chiar de subsemnatul, independent de ei.. dar cu ajutorul Dr. Mircea Razush /'pe unde o mai umbla acest fanatic cercetatoor...'?
Deh, asa se scrie istoria si acum multi vitezi se arata.... ; pacat de noi, romanii, modesti si lipsiti de sprijin autentic - le-am prescris natura efortului inca de acum 30-40 de ani..... Of Doamne...?!

--- On Sat, 8/21/10, Mircea Olaru wrote:

From: Mircea Olaru
Subject: Fw: Delays and canoe sprint world champs from Poland
To: "victor mociani"
Date: Saturday, August 21, 2010, 6:10 AM

iata ceva care te-ar putea interesa .....
stiu ca ai 'fobia' canoistilor ....
dar se merita, asa ai sa fii la curent cu noi info....

hai pa
ti-a placut ds. 'Helicopterul din Bucegi'..?

Bucuresti, Romania ++40722476223 = noua adresa a blogului

----- Forwarded Message ----
From: The Science of Sport
Sent: Sat, August 21, 2010 4:07:31 PM
Subject: Delays and canoe sprint world champs from Poland

The Science of Sport

Delays and canoe sprint world champs from Poland

Link to The Science of Sport

Posted: 21 Aug 2010 03:11 AM PDT
The Sprint Canoe World Championships in Poland - poor pacing costs golds

Well, it's been a long time between posts, please accept my apologies. I will blame:
a) burn-out (leading to writer's block!) after the Tour de France and FIFA World Cup,
b) A backlog of work after the Tour de France and FIFA World Cup,
c) a relatively quiet period for global sport, at least in terms of insights and analysis

and not necessarily in that order...

Canoe Sprint World Championships

Then most recently, and as I type this, I am in Poland, specifically a town called Poznan, where I am attending the International Canoe Federation (ICF) Canoe Sprint World Championships. I've been fortunate enough to be assisting a small group of our SA sprinters, first to help set up at high performance system, then helping where I can with physiological preparation and overall high performance strategy, and I've come over here to get a feel for the regatta in the lead-up to the main goal, the London Olympic Games of 2012.

So far, so good - an A final in the K2 500m tomorrow, and the heats and semi-finals in the K2 200m later today. For those interested in reading more, the coach, Marcus Melck's site can be found here, and our two top sprinters, Shaun Rubenstein and Mike Arthur, have their own websites, which you can read here (Shaun) and here (Mike), respectively.

A great deal has been done for these guys in the last 12 months, from the laboratory, onto the water, back into the labs, and much still has to be done between now and the Games. Perhaps when it is over (with a medal the result, I hope!), it will make a great case study for high performance sporting systems in an environment (South Africa) where support and HP expertise from the top is minimal, and in a sport where resources are scarce.

Also, sprint kayaking offers plenty of fascinating sports science applications, ranging from hydrodynamics to technique, biomechanics, pacing strategies, strength and conditioning and performance analysis, so it has been a very stimulating year, culminating here in Poznan on route to London!

Insights from Poznan - kayaking off the pace as a commercial entity

I've gained some really important insights over the last week, and have a number of thoughts on topics ranging from marketing and commercialization of the sport of kayaking, all the way to physiological preparation.

Sprint kayaking has a personality crisis, because it has never succeeded at making its stars accessible to sports followers outside of a small circle of enthusiasts. For example, if you are reading this in South Africa, you either now Shaun and Mike as Olympic medal hopefuls, or you've never heard their names. The only factor that determines which camp you fall into is whether you yourself are a paddler - those who paddle, know, those who do not have probably stopped reading!

And this is a failure of marketing. Now, having experienced a regatta, and one which is supposedly at the very highest level (it is the World Championships, after all), it's clear that the problems are related to a myopic approach from within the sport. There are barriers, certainly - 80% of a 1000m race is virtually impossible to watch as a spectator, so the competition doesn't come alive nearly enough. The distances between fans and athletes makes identification and interaction with paddlers difficult.

However, I've been very fortunate to have attended other big events, and experienced them from both 'inside the ropes' and 'outside the ropes', and the ICF would do well to learn from events like the Tour de France, and most notably in my experience, Sevens Rugby, in terms of how the competition provides a platform for a bigger entertainment event and for its athletes. The TV coverage is narrow and poor, and resembles what other sports were doing in the late 1980s, and this restricts media coverage, sponsorship potential, and spectator interest. But enough of that, that is a topic for marketing discussions some day.

Pacing strategy - how good pacing wins gold medals

Of more interest scientifically is an observation on the pacing strategy adopted by the very best paddlers in the world. This is a topic "straight out of the oven", because I've just watched the final of the Men's K1 1000m event, one of the premier events at the regatta.

Take a look at the graph below, and then we'll chat about the very, very different strategies employed by the eventual gold medalist, Max Hoff (the blue line), and the silver medalist, Tim Brabants, of the UK, shown in red. Bronze medalist Aleh Yurenia is shown in green.

So the race was won by Max Hoff of Germany, in a time of 3:29.544, only 0.5s ahead of Tim Brabants. But the real story was Hoff's comeback over the final quarter of the race. I was standing more or less 100m from the finish line, and I can assure you that Brabants was still in the lead at that point. The light blue text boxes show the gap between Brabants and Hoff for each 250m interval.

Brabants led at 250m, a full 0.88 seconds ahead of Hoff. The fast start is typical of the event, and recent research backs this strategy as optimal for events lasting about 3 minutes. The Belarussian was in 9th at that point, over 2 seconds down.

Then, Brabants' lead grew by 0.32s up to halfway, which he hit in 1:42.19, compared to 1:43.39 for Hoff (1.2 seconds down). From 500m to 750m, Brabants continued to pull away, adding a further 0.78s to his lead. By now, with 250m left to race, he is 2 seconds clear of Hoff, more than a boat length (see video later).

Hoff's finish, Brabants is finished - pacing pays at the end

All the while, paddlers I'm standing with are saying that this is typical of Brabants, who always goes out very hard and then hangs on. In terms of pacing, however, it is foolish. The problem is not necessarily a fast start. In fact, a recent study by Andrew Jones found that in events lasting 3 minutes, a fast start optimizes performance, possibly through its effects on oxidative energy contributions, which spares glycolytic energy supplies for the end-spurt.

Rather, the problem is the interval from 250m to 750m, where Brabants pushed on, opening a lead over all the rivals - watch the video below and you'll see this.

Now, we know that in virtually every single type of sport, as soon as the event lasts between 3 and 5 minutes, the optimal pacing strategy is a fast start, then a slowing in the middle and an increase at the end, so that the two halves are close to even, but there is an "inverted U-shape" (which you see Hoff and Yurenia achieve in this race above, whereas Brabants gets slower and slower. You may not think it's much, but he loses by just 0.5 seconds - it's plenty). This is why the first and final laps of mile and 1500m world records are significantly faster than the middle two laps.

When races are short, like a men's 400m or 800m run, or the men's 200m or 500m kayaking event, then it's different - the best strategy then is to go out hard and accept some kind of deterioration at the end of a race. Longer races, like men's 5000m and 10000m running events, the marathon, the Tour, all benefit from even pace, or even a slower start, with an 'endspurt' in the final kilometer. It's not co-incidence, for example, that in 24 of 25 World Records over 10,000m, the fastest kilometer has come at the very end of the race!

But for an event lasting 3 to 4 minutes, like the 4000m cycling pursuit, a 1500m run, or this K1 1000m kayak event, the optimal way to race is to hold reserve over the first half and then finish almost as fast as you begin.

Brabants did not - his first 250m was 4 seconds faster than he was able to achieve at the end of the race. The eventual result was a first half that took 1:42, a second half that took 1:48 (six seconds positive). Hoff, meanwhile, cut the race into a 1:43 and a 1:46 (3 second positive split).

These are tiny margins for error, of course - 1 second over 500m, but I have little doubt that had Brabants conserved even 1 second on the second or third 250m split, he would have greater reserve capacity that would have allowed him to hold on over a fast finishing Hoff. The strategy above is simply not the way that physiology says one should race. Why then would it happen? Because individuals have preferences for how they race for psychological reasons, they like to "front-run", or they prefer to chase.

But at this level, errors in pacing are so costly that this has to almost be trained out of the athlete. Brabants did not need a boat-and-a-half lead over Hoff with 250m to go. He perhaps needed (or wanted) one boat length, and the energy conserved by that second might have made the difference to the colour of the medal he received only 30 minutes ago.

Hoff, meanwhile, did it exactly right. And here's the thing - the Germans are all racing this way. Every single race featuring a German paddler sees them move through the field, while seemingly everyone else is producing enormous positive splits. Are they the only ones who have figured out how to pace a race? From what I've seen here, it would seem so...And we are not so different that each individual has an optimal pacing strategy. Yes, some are better at sustaining faster starts than others, some are better at kicking later in races. Much of this is psychological, I feel, but there are likely physiological reasons too. But these physiological differences are not so large that anyone can get away with vastly different strategies. For some reason, Germany have figured this out and are winning races that physiologically, they might otherwise have lost.

The video of the race is below - apologies for the language, I can't find an english one. But note the gaps that Brabants builds from 250m to 750m, and then at about 3:00 into the race, watch how the stroke rates change, as Hoff builds and kicks, Brabants begins a slow decline that almost sees the Belarussian take silver.

Pacing pays...ask Max Hoff.

More to come in the next few days!


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----- Forwarded Message ----
From: Victor Mociani
Sent: Sat, August 21, 2010 5:34:42 PM
Subject: Fw: Delays and canoe sprint world champs from Poland


Multumesc pentru"noutatile stiintifice" .....ce le-am elaborat la inceputul anilor '70 si datorita acestei "gaselnite romanesti" - FISA a introdus cronometrajul intermediar pe distanta de concurs.

Noi, canotajul academic, am abordat un mod logic de parcurgere distantei de concurs rezultat din determinarea resurselor energetice care asigura deplasarea pe distanta de concurs.

De aici si modelul "cele cinci degete"pe care le-ai scris si in cartea ta.

Modelul determinat pentru canotaj am facut-o printr-o speculatie matematica "proiectia inversa acurbei logaritmice a lui Zatiorski"din punctul in care este situata proba de canotaj. De altfel aceasta este valabila la toate sporturile ce se deplaseaza in timp si spatiu, deci si la voi, la inot ....

Curbele aratate corect ar fi sa arate ca un "U" si nu ca un "N", asa cum este prezentat in materialul pe care mi l-ai trimis.

Pe axa verticala de jos ar trebui sa inceapa cu timpii cei mai slabi si spre varful ei timpii cei mai atunci se poate vedea ca:

- la primul 1/4 al cursei se inregistreaza timpul cel mai bun,

- la 1/2 mai slab,

- la 3/4 egal sau putin + ori - fata de 1/2,

- iar la sosire din nou se apropie de valoarea primului 1/4.

Inchipuieti un lighean de spalat taiat in doua marginea la taietura arata ca un "U" ceva mai desfacut. Acest lucru este determinat de intrarea in actiune a diferitelor resurse energetice de care dispune sportivul sau care pe parcursul distante se resintetizeaza... dar nu e cazul sa tin acum o expunere pe acesata tema.

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