Riding a bike is fun. It is a great way to get exercise, it allows the rider to get a better (and often closer) view of the road and surrounding areas and it is a very eco-friendly form of recreation/transportation.
My friend Yucca Gemini likes to tell me that I ride for “sport” whereas she says that she rides for “life.” While it is true that I do not use my bike for commuting to work or to go shopping (as Yucca and millions of her Dutch countrymen do) I also ride for life. Riding keeps me fit, it helps me keep my weight down and bone density up; I have had asthma since I was a little kid and bike riding helps me maintain healthy levels of lung capacity which comes in handy when the inevitable asthma attack hits me.
I went for a bike ride on Sunday and it was a tad windy day down by the Pacific Coast Highway. Sunday’s windy conditions gave me an opportunity to use my new, handy-dandy hand-held anemometer. The La Crosse Technologies Anemometer EA 3010 is a neat little gadget that allows the user to measure current wind speed and temperature. It also allows the user to record average speed, highest speed and wind-chill factor.
Last Sunday was the first time that I had an opportunity to use the anemometer. During my 25 mile ride, I recorded headwinds of almost 23 miles per hour. The average head wind speed during my ride was a little over 10 mph. My own average speed, over the 22 mile course (using my mountain bike) was just over 12 mph.
High headwind speed. Click on image for larger view.
Average wind speed.
With these numbers in hand, I wondered what my “real” speed was, taking into consideration the wind conditions that I had encountered during my ride. Unlike climbing hills, which have definite beginnings and ends, the wind does not. The wind keeps right on whipping your face or sides -- and you never know when it might start up again (or when it might end). Unlike climbing, there is no way to plan for recovery. I just to think that riding hills was the only way to achieve bike Nirvana (otherwise known as a strong heart and a strong pair of legs); lately, however, I’ve come to realize that riding in the wind, much like riding the hills, does (and can) make you stronger.
I am not particularly good with Math and/or Science; in fact I am really lousy at both. But I do want to know more about the science of bike riding, especially as it relates to riding in the wind. After doing some research, this is what I have found.
Overcoming wind resistance (aerodynamic drag) presents the main effort for bicyclists (this is true on a windy day as well as in a calm day). The effort of pushing one’s way through the atmosphere is so limiting that most bicyclists ride in a fairly narrow speed range below 20 mph; this is true regardless of whether racing, touring or shopping.
A headwind will significantly increase pedaling effort and affect cycling performance. Aerodynamic drag is proportional to the square of relative wind-speed. The relationship between effective air speed (ground speed plus head wind speed) and the resistance to pedaling (energy needs to overcome this resistance) is an exponential one. This means that doubling air speed will MORE THAN double the Calories expended per mile traveled. For example, adding a 5 mph headwind to a ground speed of 20 mph has a much greater affect on you total energy requirements per mile than if you are riding at a recreational pace of 10 mph (with the same 5 mph headwind). In other words, assuming a constant headwind, the FASTER you pedal the more effort it requires to move the bike.
Another interesting fact that I learned from my research is that as a rider moves through the air a vacuum is created behind the rider. This vacuum has the effect of “sucking” the rider back. If you watch bike riders in action (or Formula One or NASCAR drivers) you will notice that they get as close as possible to the bike (or car) in front to ride in the front runner’s “slipstream.” This is called drafting and the effect (for the vehicle drafting) is to reduce the effort necessary to move through the wind – thus saving a considerable amount of energy and effort. Of course, this “sucks” for the rider in front; not only is the rider fighting to cut through the wind, but she is also fighting to overcome the vacuum that sucks her back.
No wonder that riding into the wind can be such a pain…in the back!
Are there any secrets to dealing with a headwind? Well, you can try getting the most aerodynamic bike possible, you can try riding in the “tucked in” position and you can try losing some weight (yes, the less you weigh, the easier it is to “move” the bike). But of all the things that a ride can do, nothing beats having a good attitude!
You can't do anything about a headwind, other than staying home and watch TV. So you might as well have a good mental attitude and welcome the wind as an aid to becoming a better rider. Think of it as a form of hill climbing (at slower speeds, each 5 mph of wind speed equals ~1% of grade i.e. a 20-mph headwind would equal a 4% hill). If you look at the wind as a training aid, then it will become a challenge rather than something to hate for part of your ride.
So go out there and ride like the wind!
L'ETAPE de TOUR
Congratulations to Arcabulle Odriscoll. On Monday, July 20, 2009, Arc completed L’Etape de Tour by riding his bike all the way up to Mont Ventoux.
Arc’s time, from the bottom of Mont Ventoux, to the top (at an altitude of approximately 1920 meters) was 2 hours and 50 minutes.
Arc’s numbers were as follows:
Time to the top of Mont Ventoux: 2 hours and 50 minutes
Elevation from bottom to top: 1920 meters (6233 feet). By comparison, Denver Colorado, the Mile High city sits at 5,280 feet (1,609 m) above sea level
Distance to the top of Mont Ventoux: 22 km (13.6 miles) at a gradient of 7.6%
Average speed over the entire course: (17.35 km/hour or about 11 miles/hour)
Participants: Over 9500 riders started the ride, only 7396 finished the ride.
Overall time: 9 hours
Course
Distance: 170 km (105 miles). By comparison, the distance from Los Angeles to Santa Barbara is approximately 98 miles.
Congratulations from your friends at BH on a GREAT ride.
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