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262
INVITED COMMENTARY
International Journal of Sports Physiology and Performance, 2010, 5, 262-267
© Human Kinetics, Inc.
De Koning is with the Research Institute MOVE, Faculty of Human Movement Sciences, VU-University
Amsterdam, Amsterdam, the Netherlands.
World Records: How Much Athlete?
How Much Technology?
Jos J. de Koning
The quality of performance during international competitions such as the Olym-
pic Games and various world championships is often judged by the number of
world records attained. The simple fact that world records continue to improve
is evidence that sports performance is progressing. Does this also mean that ath-
letes are improving? Is the continual progression of world-record performances
evidence that contemporary athletes are superior to the athletes who performed
in the past? Technological developments may obscure insight into the athletic
enhancement made by athletes over the years. This commentary tries to separate
technological and athletic enhancement in the progression of world records by
the use of a power balance model.
Keywords: performance, modeling, innovation, athletic equipment, speed skating
At the Olympic Winter Games of 1956 in Cortina d’Ampezzo, Italy, the gold
medal in the 1500-m speed skating event was won, jointly, by the Russian skaters
Yevgeniy Grishin and Yuriy Michaylov, with a world-record time of 2:08.6. They
skated on a rink prepared on Lago di Misurina, at an altitude of 1754 m. At present,
15 Olympic Winter Games further in time, the world record has progressed (Figure
1a) and currently is held by Shani Davis from the United States in 1:41.04, skated
at the Utah Olympic Oval, Salt Lake City, Utah, at an altitude of 1423 m, in a venue
with many other world records. Is Davis really that much superior to Grishin and
Michaylov? Historical images and lm footage show that not only skating equipment
has changed, but also skating style and the intensity of racing. A part of the 27.56-s
improvement is clearly attributable to technological development. Presumably, a part
is also attributable to the athletic enhancement of the skaters. Obvious technological
improvements in speed skating include better preparation of the ice surface, aerody-
namic racing suits, and the introduction of clap skates (Dutch, klapschaats).1,2 The
effect of these technological innovations can be at least partially accounted for by
modeling with power equations, which makes it possible to estimate the inuence of
each of these improvements on performance.3,4 An adjustment of past performances
can thus be done to estimate what historical performances would be if corrected
for technological improvements. In this way, the progress of world records can be
evaluated with the current technological status as reference.
Modeling World Records 263
The Model
The velocity of a skater is related to the power produced by the athlete and the
power lost to the environment. The power produced is the aerobic and anaerobic
energy systems adjusted for the efciency of power transfer to propulsion. The
power losses consist of losses to air and ice friction as well as changes in kinetic
energy.1,4 The relation between velocity and power needed to overcome the air
frictional force is nonlinear and depends on the aerodynamics of the skaters and
their garments as well as on environmental circumstances. Studies on the aerody-
namics of speed skating1 have elicited detailed information on the effect of skating
posture, anthropometry, type of clothing, altitude, and net air motion at the venue
(eg, wind). These factors, except air motion at the venue, can be lumped together
into the aerodynamic coefcient. The relation between velocity and power to
overcome ice resistance is linear.5 Ice resistance depends on ice temperature, the
method of ice preparation, and the type of skate blade used, and is accounted for
in the coefcient of ice friction.
At a given magnitude of these coefcients, we can calculate the power demand
for any skating velocity. Taking coefcients that belong to the contemporary situ-
ation (indoor oval, high altitude, aerodynamic suits, excellent ice preparation) and
calculate the power demand to skate the world records that were set during the last
15 Olympiads (Figure 1b), we get an underestimation of the actual power output
necessary for skating each record. Technological development has reduced the
values for the aerodynamic coefcient and the coefcient of ice friction over the
years, so a correction of these coefcients needs to be done to estimate the real
power demand that belongs to each record. The altitude at which each record was
skated also needs to be taken into account. With these values accounted for, the
power output required to achieve the performances at the moment they were set
can be estimated (Figure 1c).
With historical information about the location and altitude of world record
rinks, the coefcients can be adjusted and the probable power output necessary
to skate each record can be estimated. This power output can then be used as
the basis for a recalculation of the historic 1500-m race with the power balance
model to estimate the virtual time of historic world records, as if they were skated
under the same circumstances as when the current world records were set. The
progress from the corrected world records calculated with this procedure, reect
the technology-independent enhancement that the athletes have achieved (athletic
enhancement; Figure 1d).
Technological Developments Made
During the Past 50 Years
In the 1950s and early 1960s, speed skaters were dependent on Mother Nature when it
came to ice conditions. International speed skating competitions were mainly held in
Nordic countries, the United States, or Soviet Russia, often at altitude. Although natu-
ral ice can be very fast, the absence of articial freezing made the preparation of the ice
rink unpredictable. The introduction of refrigerated 400-m ice rinks and ice resurfacing
machines reduced the coefcient of ice friction considerably (from 0.006 to 0.004)1,5.
264
Figure 1 — (a) Progress in world-record 1500-m speed skating for men. Vertical lines indicate technological developments. (b) Estimated power
output for the world records assuming contemporary technology and circumstances. (c) Corrected power output based on modeling results for tech-
nological developments. (d) World records corrected for technological developments.
Modeling World Records 265
A further reduction in the coefcient of ice friction (from 0.004 to 0.0035) was
made possible by the introduction of fully covered 400-m ice rinks in 1987. From
the mid-1990s, skaters had the availability of skate blades made from powdered
metallurgic material. These skate blades reduced ice friction by another 30% (per-
sonal observation), to a contemporary value of 0.0025.
In the early days, speed skaters used knitted jerseys, tightly tted pants, and
often a woolen cap. This outt was replaced in 1974 by one-piece suits made of
Lycra-like material, form tted to the body. These suits were improved in 2002
with the addition of selected smooth and rough patches for further reduction of air
frictional forces. The traditional garment caused a 10.5% larger air friction coef-
cient than the current suits, and the latest improvement caused a reduction of 2%.1
In the mid-1980s, the Dutch scientist Gerrit Jan van Ingen Schenau invented
a skate with a hinge between the boot and the blade.1,6–9 The aforementioned clap
skate is the most signicant innovation in speed skating to date. With this skate, the
athlete is able to generate a higher power output (12%) due to improved efciency
(for details, see refs. 7, 8, 9). When elite speed skaters began using this type of
skate, every world record improved at least once within the rst year of the intro-
duction of the clap skate.
Model Calculations
With the knowledge of the above-described technological developments and the
use of the power balance model, it is possible to estimate what the world records
would have been if they were all skated under the same circumstances. Figure 1a
shows the historic progress of the world records on the 1500 m; Figure 1b shows the
power output required had they been skated with contemporary technology. These
power output values are an underestimation of the power output of the skaters during
historical world-record races because not all these innovations were available at the
time of the races. Figure 1c illustrates the model estimations for the power output
that the athletes must have produced at the time of their world-record performances.
If this power output is then applied to contemporary conditions, Figure 1d would
have been the current time for the historic world records.
The progress in performance illustrated in Figure 1d could then be seen as real
athletic improvement of speed skaters over the last 15 Olympiads. This observation
suggests that roughly half of the progress in world records comes from technology
and the other half from real athletic improvement. However, published values of
muscle power output and/or VO2max in elite skaters have not changed meaning-
fully over this time period.2,10–13 Accordingly, it must be assumed that skaters have
become more efcient over the same period of time, so that the net skating power
output has increased despite little change in the biological power output. This
seems to be reasonable in terms of the increase in the amount of specic skating
training undertaken by contemporary skaters. The advent of professional teams and
the availability of year-round indoor ice rinks have massively increased the total
number of specic training hours. In the 1950s, it is likely that skaters could only
skate during 3 mo of the year (approx. 60 skating days per year, often with practices
abbreviated because of very harsh weather conditions). By 1980, with the advent
of articially cooled ice rinks, the number of skating days per year had perhaps
increased to approximately 100 per year. Contemporary skaters rarely go a week
266 De Koning
without skating and probably have >200 skating days per year. Specicity of training
is probably a critical element, as speed skating is a highly complex motor task that
must respond favorably to more specic training. The crouched position of speed
skaters has a large inuence on the blood ow and oxygenation of the leg muscles.13
Specic training could have an inuence not only on the effectiveness of motor
coordination patterns, but also on physiological adaptations. Traditionally, speed
skating was a seasonal sport with a large amount of nonspecic summer training
(running, weight lifting, plyometric exercises, and cycling). With the introduction
of refrigerated and covered skating rinks, the amount of specic training has sub-
stantially increased. In addition, short track speed skating and in-line speed skating
have become training modes and sources for an increasing talent pool. As recently
as 1990, long track speed skaters would have scoffed at the concept of skating short
track in the summer as a means of technique improvement. It can be assumed that
these developments have inuenced skating efciency positively, although historic
measurements of skating efciency are not available for comparison. However,
even the experimentally determined efciency of contemporary elite speed skaters,
values around 0.172,7 are still low compared with cycling.
The increasing speed of the skaters through the years also inuenced the skat-
ing style and racing style as well. Contemporary skaters bend their skate blades
slightly for better skating in the turns, and their race strategy has a more all-out
character. Because they are going faster, they can afford to go harder early in the
race. Accordingly, the 1500-m race has become a long sprint. The luxury of using
this all-out strategy has further contributed to the advancement of world records.
Some limitations in the way the model is used deserve mentioning. In the
presented estimations, the individual variation in skating style was not included.
Theoretically it would have been possible to include this if data on anthropomet-
ric parameters and skating position were known. Unfortunately, historic archival
material is very limited, so it is difcult to adjust the model for these factors. The
same holds for historic meteorological conditions. It must be assumed that during
all world-record performances these variables were close to optimal. However,
fans of skating can point out many examples of world records that occurred in less
than ideal climatic circumstances, which suggests that our estimation of how fast
historic athletes might have gone is still underestimated.
The corrected world records in Figure 1d show some extraordinary perfor-
mances. The world record set by Gulyayev in 1987 (1:52.70) and the world records
set by Ritsma and Koss in 1994 (1:51.60 and 1:51.29) corrected for technological
developments are performances (1:42.3, 1:42.6, and 1:42.3 respectively) in the
range expected for contemporary Olympic athletes. On the other hand, some records
set in 1997, immediately following the introduction of the clap skate, turn out to
be nonrecord performances when corrected for technological advantages. These
skaters were perhaps lucky to be the rst skaters of international level who dared
to take advantage of innovative developments. However, in high-level sports, the
courage to try innovative equipment is an admirable quality in its own right, so no
disqualifying comments are intended toward these athletes.
In summary, it can be stated that the progress in 1500-m world records during
the last 50 y can equally be attributed to technological developments and athletic
improvement. The athletic improvement represents an approximately 25% increase
in power output. However, when one considers that the increase in specic training
Modeling World Records 267
time has also increased markedly over the last 50 y and that estimates of skating
efciency are hard to correct for, it may not be unrealistic to suggest that the historic
champions would compete very effectively under contemporary conditions. The
present analysis was limited to responses in speed skating. However, we believe
that the principles presented in this commentary might allow similar correction for
historical performances in other sports.
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