Bicycle commuting

Bicycle commuting is the act of commuting to a place of work or education by bicycle, a common form of utility cycling. Bicycling is the dominant mode of commuting in countries such as India and China and is also common in many European countries (though rare in most parts of the United States).

In the West it is common to combine bicycle commuting with public transport (also known as mixed-mode commuting). Folding bicycles are used if space, fees or restrictions interfere with taking full size bicycles along. Another alternative is to have a bicycle parked at a station.

Worldwide the bicycle is probably the most common commuter vehicle, and the second most common form of commuting after walking. While the absolute number of bicycles in existence globally may not be known, it is clear that significantly more (about twice as many) bicycles are produced than automobiles.

While different hardware serves different users in different countries, the following features are useful to many: a rear rack or panier, lights (preferably driven by an axle dynamo), disk brakes, fenders (also called mudguards), a chain guard, Hub gears, and an upright sitting position.

http://en.wikipedia.org/wiki/Bicycle_commuting

Bicycle (Health)

Bicycles are often used by people seeking to improve their fitness and cardiovascular health. In this regard, cycling is especially helpful for those with arthritis of the lower limbs and are unable to pursue sports that cause impact to the knees and other joints. Since cycling can be used for the practical purpose of transportation, there can be less need for self-discipline to exercise. Interestingly, it has been found that despite toning the leg muscles, cycling actually causes buttocks to lose tone and muscle.

Cycling while seated is a relatively non-weight bearing exercise that, like swimming, does little to promote bone density. Cycling up and out of the saddle, on the other hand, does a better job by transferring more of the rider's body weight to the legs. However, excessive cycling while standing can cause knee damage. It used to be thought that cycling while standing was less energy efficient, but recent research has proven this not to be true. Other than air resistance, there is no wasted energy from cycling while standing if it's done well.

Cycling on a stationary cycle is frequently advocated as a suitable exercise for rehabilitation particularly for lower limb injury due to the low impact that it has on the joints. In particular cycling is commonly used within knee rehabilitation programs.

Excessive saddle height can cause posterior knee pain, while setting the saddle too low can cause pain in the anterior of the knee. An incorrectly fitted saddle may eventually lead to muscle imbalance. A 25 to 35 degree knee angle is recommended to avoid an overuse injury.

http://en.wikipedia.org/wiki/Cycling