from lance to chimps via godzilla...

As I was taking a walk a peloton of perhaps 30 bikes whizzed by in relative silence.  Everyone was dressed in the lycra uniforms that cyclists seem to prefer and each bike probably cost well north of $5,000.  There are several groups of serious amateur cyclists around here.  You rarely see people commute on bikes, but there is a small racing culture.

 

The train wreak that is Lance Armstrong made me think of how cycling has changed over the years.  When I was young that's how kids got around - cheap transportation that offered freedom.  In college I took up riding to unwind on weekends along with commuting as I didn't have a car.  I joined a club that regularly took 100 mile rides - centuries - and found them to be an ideal way to unwind from the pressures of school.

 

There wasn't any lycra, helmets were rare and most of the bikes were inexpensive Schwinns.  The lack of proper kit didn't make any difference.  None of us followed racing.  Bicycles were simple transportation.

 

Somehow biking faded.  There was a resurgence for awhile as "mountain" bikes appeared, but it was a fad for most people.  But then this guy named Greg LeMond won the Tour de France.  Greg was an American - an American who managed to break down a barrier by winning a quintessentially European race.  People took notice and amateur athletes took up cycling.  Then a more remarkable series of events - Lance Armstrong came along winning several consecutive Tours.  His performance was nearly super-human with a power output in the mountain stages that was freakish - fewer than one in a billion people would have that sort of capability.  Not to mention he was a cancer surviver.

 

Amateur cycling in the US became a big thing.   Cycling for commuting and for the fun of it was still fading, but a visit to a bicycle store revealed serious exotica.

 

My cycling club in college had an interesting connection.  Paul MacCready had developed an interest.  Not in cycling, but in cyclists.  He was mounting a challenge to the Kremer Prize - £50,000 to the first person who could take off, stay at least ten feet above the ground and complete a figure eight around two pylons separated by a mile and a half.  Many had tried, but materials had changed and Paul happened to be a serious boffin when it came to aerodynamics and aircraft design.

 

Finding the right engine was important.  I can't quote the exact numbers, but something around 400 watts were needed for takeoff and perhaps 250 watts for cruising - assuming the pilot was *very* light.  Bryan Allen was an amateur cyclist who could develop enough power while not weighing much - probably under 130 pounds.  To cut a long story short they not only won the prize in August of 1977, but went on to cross the English Channel with an improved airplane.

 

If you've ever been around a group of world class cyclists you are struck by their size.  They are rarely over 5' 9 and tend to have amazing leg development while having very little muscle in their arms - not terribly surprising.  The rules of many sports conspire with physics and physiology to give world class athletes in a given event very similar body types and sizes.  A great luxury of just doing a sport for fun is hard work and passion can produce results that are good enough to keep you going, but as the level of competition increases there is a selection driven by genetics - you won't see 6' gymnasts or 5' 5 basketball players in Olympic competition.  Even with freakish athletic abilities physics gets in the way.

 

For some sports "bigger is better" doesn't hold.  Some sports favor the ability to change the direction your body - or part of it - is traveling.  Others require pure strength.  For those you either need the largest possible muscle or create special classes to allow athletes of a range of size to compete.

 

Here is where scaling comes in ..  if you scale up a body by some amount, how much does his or her strength change?

 

The strength of a muscle depends on how many muscle fibers are pulling together - strength increases as the cross sectional area of the muscle.  A person's cross sectional muscle area changes as the square of their height.  Their weight, on the other hand, increases as the cube of their height.¹  What is important to note is their strength to weight ratio changes as the square of their height divided by the cube of their height.  The chart shows a reasonably good correlation between the olympic records for the "clean and jerk" and the weight of the athlete to the two thirds power.   The smallest class of weight lifter can have lift three times his own weight while the largest class world record holder can only lift about 1.7 times his own weight.

 

There are some interesting consequences.  This limits the size of animals.  Scale up an animal and you reach a point where it is simply too heavy for its muscles to move around.  Scale down an animal and its strength to weight ratio increases dramatically. Godzilla wouldn't be able to move.²

 

Some sports like discus and hammer throwing don't have weight classes, so only pure strength is valued and the largest athletes have an enormous advantage.  Other sports, like cycling, have more complex interactions dictating ideal size and weight.³

 

This brings up back to the elite of the elites.  There are some sports where you need genetics that are one in a million or even one in ten million to compete at the highest level.  Someone like Lance Armstrong recorded such freakish performance racing in the mountains that it was more like one in a billion - or even rarer.  The problem with cycling is there are perhaps fifty cyclists at least one in hundreds of millions ... an indication of foul play.

 

Doping of one form or another exists in some sports.  Much of this is dangerous, but where do you draw the line?  Caffeine has been shown to enhance some types of performance as an example.  What is the acceptable normal for a human and what are we comfortable with kids emulating?⁴   Already we have seen debate over "handicapped" athletes like Oscar Pistorius in the London Olympics  We are nearing the point where an elite athlete might have an advantage by amputating limbs replacing them with artificial limbs that use exotic materials. There are advantages for runners as well as cyclists.  And we are on the verge of manipulating genes - some of the modifications may be unhealthy, others may prove to be neutral or even healthy.  It comes down to the fundamental question of what competition means and where we draw lines.  Many sports at the most elite levels have become entertainment with the potential for great financial reward.  We've seen many athletes trade the increased chance of a shortened life for short term rewards.  Watching the Lance train wreck play out and seeing if it changes cycling may be an indicator of what we tolerate - at least for the present.

 

The good news is most of those who play amateur and school sports are not playing at the elite level and don't need to be in order to be happy.  Doping and body modification, along with a need to be an Olympian, are just not important.  Short people can participate in sports that favor height and make up the difference with training and passion.  Tall or short people can cycle.... the list goes on and on.  

 

A few years ago I spoke with the athletic director of an academically elite school.  They require three semesters of physical education for all undergrads. They participate in N.C.A.A. Division III, and their record happens to be at the bottom of the barrel.  What impressed me was the school's attitude towards sport.  Their goal was to allow students to find physical activities that they liked well enough to continue on their own for life. The goal was to provide counterpoint to what was likely to be a sedentary work style and promote health over the long term.  They saw themselves as having a mission to act as a personal trainer.  Team sports and competition are a driver for some of their students, so they participate.⁵

 

And that leaves chimps.  An adult chimp is seriously stronger than any human - their strength to weight ratio is off-scale relative to ours.  This seems odd as they are close relatives sharing about 99% of their DNA with us.  The trick is they lack fine motor control - their muscle fibers are wired to contract in large groups where ours contract in much smaller groups and we can't contract the same percentage of muscle fibers as they can.   A chimp baseball player might have a wicked left hand, but their ball control would be seriously lacking and their handwriting would be awful.

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¹ Assuming their body shape and density remains the same.  A good first order assumption for very elite athletes in a given sport.  Area will increase as the square, volume as the cube.

Specifically if the length of an object with an area of a₁ changes from l₁ to l₂ the new area a₂ will be 

a₂ = a₁(l₂/l₁)²

double the length and the new area increases by a factor of four, triple it and it increases by a factor of nine. 

The volume will increase by the cube of the length.  

v₂ = v₁((l₂/l₁)³

Now doubling the length increases the volume by a factor of eight, tripling increases the volume by a factor of twenty seven. 

Since strength is proportional to the cross sectional area of a muscle and weight is proportional to their volume if everything is scaling uniformly, a person's strength to weight ratio changes as the square of their height divided by the cube of their height.  Or as their weight^2/3

It is important to stress that this ratio only holds if everything is scaled.  My friend Colleen, at 6'7, is about 23% taller than the average adult female.  Appling simple scaling, you would expect her to weight 86% more, but she is both thinner and more muscular and her ratio of leg length to height is much greater than the average female, so the rule doesn't hold.  Simple scaling breaks down when body proportions change and variation is common with extremely tall and short adults. What is true is she is quite a bit stronger and heavier and the length of her limbs means she can't accelerate them as quickly as a smaller person.  The rules of volleyball give her a great advantage in many positions, but less where quick movements are necessary.  This means she needs a teammate who is significantly smaller and capable of greater accelerations.  Woman's beach volleyball seems to favor those with a height of about 6'0 to 6'2 and a slim build.

² Not only would Godzilla not be able to move, but his bones wouldn't be able to support his weight.  Note that elephants have to have much thicker bones proportional to their size than smaller animals just to deal with the extra weight.  

³ It would be fascinating to make a composite representation of the measurements of the top ten athletes in every sport (accounting for specialists in team sports) and make a chart of the silhouettes ranging from the smallest gymnasts to basketball centers.  There is a lot of physics going on!  

⁴ I couldn't find the reference, but someone published the weights of line backers on top ranked high school football teams in Texas over the past fifty years.  The increase was greater than you might expect for recruiting very large boys and giving them enormous amounts of weight training.  There is a chance that doping is taking place.

⁵ The school is Caltech.  Oddly enough they managed to violate the N.C.A.A academic eligibility requirement. Very strange as Caltech may be the most selective school in the nation.

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Recipe Corner

 

I'm a big fan of garlic and of pressure cookers.  Why not use to pressure cooker to cook garlic?  You'll need a trivet for your pressure cooker and a small steamer basket.  Most pressure cookers come with trivets.

I'm still exploring my pressure cooker and am finding it extremely useful - you can save a lot of time and energy plus modern cookers are very safe.  I use a Kuhn Rikon - a bit spendy, but well-made and recommended by every experienced user I talked to.

 

Roasted Garlic

 

Ingredients

 

° 3 large garlic bulbs (see if that will fit in your steamer)

° a bit of high quality extra virgin olive oil

 

Technique

 

° chop the top quarter or so off the top of the garlic bulbs - keep the top section for your future garlic needs

° pour about a cup of water into your pressure cooker and place the bulbs cut side up in a steamer that sits on a trivet  

° cook for about 5 minutes on high pressure and then let the cooker come back to atmospheric pressure naturally - e.g. - just move it to a cold burner and let the pressure come down by itself

° remove the bulbs with tongs, place them in a heat-proof dish and drizzle the olive oil over them.  Broil on the top rack of your oven until they are nicely caramelized - about five minutes in my case.

° yum!