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Vol.
XXVIII No. 34
August 22,
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Olympics
And The Limits To Human Performance
Amit
Sen Gupta
THE
greatest sporting spectacle is now underway in Athens. The Olympic games are a
test of the limits to which the human body can be made to perform. The motto of
the Olympic Games Faster, Higher, Stronger is symbolic of this quest for
excellence, the quest for trying to reach the absolute limits to which the human
body can be pushed. Over the last century athletes competing in the Olympic
games have pushed their performance to higher and higher levels. That brings us
to the obvious question are we nearing the limit of human performance?
The simple answer to the question would be: not
yet, but records are being broken by ever narrower margins. When we plot a graph
showing how the best performance in a given event changes over time, we see the
graph leveling off. Theoretically, an absolute limit to how far or fast the
human body can go does exist, but it is impossible today to accurately predict
that limit. Perhaps the only way we will be able to recognise the ultimate
performance will be retrospectively, after a record has stood for years.
Some
experts have tried to calculate the absolute limit of performance. They take the
highest value for each crucial physiological factor ever recorded in an athlete,
such as the maximum oxygen uptake, the greatest efficiency with which energy is
burned and the best stamina. Then they figure out how fast someone might go if
these were all combined in one body. By these calculations, we may one day see a
sub-two-hour marathon or even a three-and-a-half-minute mile. But the
probability of finding someone with these exceptional abilities is pretty low.
WHAT
DRIVES PERFORMANCE?
Let
us examine what are the factors that drive performance in athletes. Much of the
increases in performance, especially in the early part of the modern area, came
from improved nutrition and improved training techniques. In developed countries
the advantage of these two factors has tapered off, even disappeared. But they
are now coming into play in the improved performance by athletes from developing
countries.
In
the last 80 years, on an average, records related to disciplines that involve
running have improved by about 10 per cent. In contrast, the triple jump record
is over 30 per cent longer, for high jump it is 35 per cent, and for long jump
it is 41 per cent. For the more technical pole vault event, the record is over
80 per cent higher than in 1896. This illustrates the fact that there has been
greater improvements in events that are more technical or where an improvement
in the apparatus makes a major difference in performance. The application of
scientific methods in training has also helped stretch the levels of attainment.
Much of Olympic sports involves mechanics and an application of the principles
of Physics has helped boost performance. The sportswear company called Speedo is
promoting the use of its sharkskin swimsuit that covers almost the entire
body. The suits are designed to simulate the skins of sharks and minimise
drag that is the resistance that swimmers feel in the water. In the jumps,
improved techniques (like the Fosbury Flop technique for high jump introduced in
1968) have contributed to advanced performance levels. In Pole vault the
introduction of the new pole made of fibreglass revolutionised the sport. Such
improvements, based on better equipment also took place in throwing events such
as discus and javelin, as well as in events such as archery and shooting.
However,
the advantage conferred by technology and improved training techniques is now
tapering off. Today, there are two important factors that continue to drive up
Olympic records. First is the fact that more people are competing today than
ever before. Statistically, that must lead to improved records. We see today the
entry of new nations that are doing well in the Olympics. They are able to do so
because of a minimum level of health and nutrition that they are able to provide
to the general population, and basic facilities for sports that a large number
of people can avail of. The performances of Chinese and Cuban athletes, for
example, have shown tremendous improvement in the last two decades. When a
country like China is able to compete on equal terms with the rest of the world,
it means an addition of one-fourth of humanity to the pool of possible
competitors.
Secondly,
those who excel are really the exceptionally talented or gifted whose
performance level is way beyond the average for the population. While improved
health, nutrition and training can and do improve the abilities and performance
levels in a general population, those who truly excel in modern day competition
are possibly also gifted with a physical and physiological advantage to start
with. Better facilities and nurturing helps to bring out this advantage.
PHYSIOLOGICAL
AND PHYSICAL ADVANTAGES
Let
us look at what these advantages could be. First is the oxygen carrying capacity
of the individual. Remember that oxygen is vital for any physical activity, as
the body burns oxygen to produce energy. The way athletes use energy differs
long distance runners require a steady supply over extended periods while
sprinters need very high volumes over a short period. The ability of the body to
deliver oxygen is determined by the lung capacity i.e. the volume of air
that the lungs can hold, as well as on the oxygen carrying capacity of blood.
Sporting performance also depends on muscle mass, and crucially on the kind of
muscle fibres that are present. Skeletal muscles, that is muscles in our body
that we use for physical exertion, have two types of fibres, categorised on the
basis of the speed at which they contract: type I, or slow-twitch muscles, and
type II, fast-twitch muscles. There are two kinds of the latter: type IIa,
intermediate between fast and slow; and type IIb, which are superfast-twitch.
Long distance runners tend to have mostly type I fibers, which have more
extensive blood supply and are packed with mitochondria, which deliver sustained
levels of energy. Sprinters, on the other hand, have mostly type II fibers,
which hold lots of sugar as well as enzymes that burn fuel in the absence of
oxygen.
Another
physiological advantage that athletes can have is a larger lung capacity and a
higher oxygen carrying capacity of the blood. This is seen typically in
populations who live in higher altitudes they need the high lung capacity as
the air they breathe has less oxygen. They also have higher oxygen carrying
capacity in the blood a larger number of red blood cells that carry the
oxygen. This explains why many of the greatest long distance runners have been
from such regions the great Finnish runners like Pavo Nurmi, Lasse Viren and
more recently the legendary Kenyan runners like Kip Keino.
DOMINATION
BY KENYANS & WEST AFRICANS
The
Kenyan runners who have dominated modern day distance running in the last 30
years are a unique phenomenon. Kenyan men now hold world records in distances of
3000-metres, 15-kms, 20-kms, and 25-kms, the half-marathon, and the marathon.
Kenyan men have won 13 of the last 14 Boston marathons. Kenyan women hold half
of the top 10 marathon times and world records in 20-kms, 25-kms, and 30-kms
distances. What is even more remarkable is that most of these athletes come from
a small area in Kenyas Rift Valley, from a group of tribes called the
Kalenjin who number little more than 3 million people.
A
major physiological advantage that the Kenyans seem to have is their ability to
withstand fatigue and sustained physical exertion over long periods. Studies now
show (reported in Science: Vol.35 July 30,
2004) that Lactate,
generated by tired, oxygen-deprived muscles, accumulates more slowly in their
blood. Accumulation of lactate leads to fatigue and diminished performance of
muscles. They have higher levels of an enzyme that breaks down lactate. As a
result it is calculated that they are able to save about 8 per cent energy per
kilometre a huge advantage at the highest levels of competition.
The
Kenyans have their counterparts from the other side of the continent West
Africa. Scientists are trying to unravel why athletes whose ancestors come from
the region have emerged as the worlds fastest sprinters. Initially almost all
of them represented the United States (descendants of those forcibly brought to
the country to work in plantations 200 years back), but now represent a number
of other countries like the UK, Canada, Jamaica, France, and others. Today, they
monopolise virtually all the short distance running events 100 metres, 200
metres, 400 metres, the 100 and 400 metre hurdles. They
hold 35 per cent of all top 900 times in the running events, concentrated
entirely in the sprints. An even more staggering statistic: all of the 32
finalists in the last four Olympic men’s 100-meter races are of West African
descent. The last time a person with an ancestry from outside that region set
the men’s world record in the 100-meter sprint was in 1960! The answer to this
phenomenon also possibly lies in the physiological advantage that athletes from
this region have because they have a higher proportion of type II muscle fibres,
i.e. the fast twitch fibres.
Are
we then suggesting that genetics determines the level of performance in modern
athletics? Not really. Genetic make up may provide a slight advantage to a group
that share certain physiological characteristics that are beneficial in a
certain sport. But this advantage is extremely small and expresses itself
only if the advantage is allowed to be nurtured. Thus,
while it is now being posited that Black sprinters have that critical edge, they
were not a significant force in world athletics before the sixties. It is only
when the conditions of Blacks in United states and other Northern countries
improved that they started dominating the sprint events. Even today those
who live in West Africa, and would presumably have the same advantage, do not do
well at the world level. So environment and training do play a very important
and critical role in the expression of the physiological advantage that people
may possess. It is entirely conceivable that in our country, with a population
of 1 billion, there are people who do have special abilities. Unfortunately our
people are still denied of the enabling environment that can help express these
abilities.
MODERN
DAY GLADIATORS?
Unfortunately,
no discussion on Olympics and records can be complete today without mentioning
the bane of doping that is the use of artificial performance enhancing
substances. Doping first started with the use of synthetic hormones called
steroids that help build muscle mass. It soon spread to include other drugs
specific to the demands of a particular sport. It included drugs that help
eliminate tremors in disciplines like archery and shooting, drugs that help
loose water to reduce weight suddenly in disciplines like weightlifting, etc.
Testing for such substances was introduced in the 1972 Munich Olympics. Since
then its been an even game as testing techniques have developed drug cheats
try to stay a step ahead by introducing drugs that are more and more difficult
to detect because they mimic the effects of naturally occurring hormones. The
huge problem of doping has put a major question mark on a number of records that
are being set today.
Sadly,
we are increasingly seeing a world population marked by regression towards
physical sloth and mediocrity that amuses itself by watching a very few
extremely genetically gifted, technically trained and sometimes artificially
enhanced “gladiators.” The Olympic movements biggest challenge
today is to make sure that it is a measure of true human endeavour. Further,
that it provides every woman and man a fair chance to compete on a level playing
field.
