Saturday, April 18, 2009

Cycling Climber

Before this I have wrote a post about domestique riders in road cycling race. Another role in the cycling team is the climber. Climber can be like domestique, lieutenant, or maybe team captain. Did you remember the US Postal Service Cycling Team back in 1999 to 2004. This team is the great example too see a lot of climber in on team. Their objectives was to make sure their team captain, Lance Armstrong to won Tour de France every year. Lance as Captain, Roberto Heras as Lieutenant, Jose Azevedo, Manuel Beltran, Victor Hugo Pena, Tyler Hamilton, Viatcheslav Ekimov, Christian Vandevelde, Dave Zabriskie, Levi Leipheimer were working as domestic when the Tour came.

Climbers tend to have a lot of endurance and specifically developed muscles for long hard climbs. They also tend to have a slim, lightweight physique, but some can become good climbers through concerted training. Ironically, many climbers are not very good descenders and many see their large time advantage diminished by the time they reach the bottom of a descent.

Many types of climber can be categorized. Firstly is climber can only climb a hill and sprinting at the top of hill.They have a small physiques but more power may specialize in short but steep climbs, also dubbed "sprinters hills". Examples include Paolo Bettini and Danilo Di Luca, who are able to sprint their way up the shorter climbs to win a stage or a single-day race.

Second type of climber is the breakaway specialist who can ride aggressively with many attacks and sustain their lead over ascents, descents, and flats. Famous examples include Laurent Jalabert and Richard Virenque.

Sports physiologists have attributed the advantage that small stature holds in cycling up steep ascents to the way in which body mass and body surface area scale according to height. As a hypothetical cyclist’s height increases, the surface areas of his body increase according to the square of his height whereas the mass of his body increases according to the cube of his height. The surface area relation applies not only to the total surface area of the body, but also to the surface areas of the lungs and blood vessels, which are primary factors in determining aerobic power. Thus, an equally-proportioned cyclist who has 50% more body mass (i.e. is 50% heavier) will generate only about 30% more aerobic power. On a steep climb most of the cyclist’s energy goes into lifting his own weight, so the heavier cyclist will be at a competitive disadvantage. There is, of course, a lower limit to the benefit of small stature because, among other factors, the cyclist must also lift the weight of his bicycle.

Scaling factors also account for the relative disadvantage of the small cyclist in descending, although more as a result of physics than physiology. A larger rider will experience a more powerful gravitational force because of his greater body mass, but he will not have as great an increase in the frontal area that creates aerodynamic drag. The downward force is proportional to the cube of height whereas the frontal area is proportional to the square of height. Descending exclusively under the force of gravity--i.e. not applying power through pedaling--the heavier rider will be faster.

Although these factors might seem to cancel each other out, the climber still has an advantage on a course with long ascents and long descents: adding several miles per hour on a slow, time-consuming climb is much more valuable than the same increase on a fast and brief descent. Any rider, of course, can improve his climbing speed by increasing his aerobic power and reducing his body weight and can increase his descending speed through better bike handling and the willingness to accept an increased risk of crashing.

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