Bicycling for transportation health and competition

By Sun Advocate

The bicycle is a tremendously efficient means of transportation. In fact cycling is more efficient than any other method of travel–including walking!
The one billion bicycles in the world are a testament to its effectiveness. The engine for this efficient mode of transport is the human body. Because bodies are fueled by food, diet plays an important role in how the body performs. Different muscle groups and types provide the power. Genetic inheritance, intensive training, and a competitive drive help top athletes push the boundaries of endurance and speed on the bicycle.
In the United States many people still consider cycling only a recreation or professional sport. But millions of Americans have found that cycling is a great way to get to work or get around town. Some cyclists are banding together and forming organizations and events advocating issues important to cyclists.
The bicycle has had a great impact on popular culture as well. In fashion, the bicycle was largely responsible for changing women’s clothing in the late 1800s. Restrictive corsets and long dresses made way for bloomers and later trousers.
It takes less energy to bicycle one mile than it takes to walk a mile. In fact, a bicycle can be up to five times more efficient than walking. When comparing the amount of calories burned in bicycling to the number of calories an automobile burns, the difference is astounding. One hundred calories can power a cyclist for three miles, but it would only power a car 280 feet (85 meters).
Unlike automobiles, which require fossil fuel, cyclists are fueled by food, a renewable energy resource. The type of food a cyclist eats can affect performance. All humans require water, protein, carbohydrates, fats, vitamins, and minerals to stay healthy. For top athletes, maintaining a proper balance of these nutrients is extremely important. During races many cyclists will use high-carbohydrate drinks, bars, or even gels for instant energy.
The human body is made up of mostly water, so even losing as little as 2 percent of the body’s fluid through sweat can adversely affect cycling performance. Athletes riding in hot conditions for extended periods need to be careful. Severe dehydration can cause heat exhaustion or heat stroke and in even in some extreme cases, death. Cyclists are instructed to drink a few cups of water before riding and then to drink often during exercise.
A cyclist’s legs provide the power for cycling. Muscle attached to the thighbone (femur) and the shinbone (tibia) do the majority of the work. The thighbone works like a lever and if it’s longer than your shinbone it will provide extra leverage on each stroke of the pedals. The length of a persons thighbone is determined by genetics. The length of the thighbone is not the whole story, though–it takes muscles to move those bones.
Thousands of thin spaghetti-like fibers make up muscle tissue. These fibers receive messages from the brain, causing the fibers to contract. The main muscles at work in cycling are the quadriceps and hamstrings in the upper leg, and the gastrocnemius and soleus in the calf. These muscles contract in a sequence that creates the pedaling action.
The quadriceps and hamstrings do most of the work when you ride a bicycle.
It’s one thing to have the brain send a message to the muscles, but what fuels the muscles during the thousands of contractions that occur during extended cycling? This has to do with the terms aerobic and anaerobic. These terms describe two ways in which muscles get energy.
In aerobic exercise, muscles draw on oxygen as well as the glucose and fatty acids carried in by the blood to produce adenosine triphosphate or ATP. ATP is the energy source that enables muscles to contract. The ability to keep exercising aerobically depends on the delivery of oxygen and fuel molecules (glucose and fatty acids) to the muscles. And that depends on circulation and respiration, provided by the heart and your lungs.
When exercising anaerobically, muscles are drawing on stores of glycogen (which is formed from glucose) and converting them to ATP. During this type of high-intensity exercise the muscles are producing energy without oxygen–the cardiovascular system is unable to keep up the demand. There is a price to pay for exercising anaerobically, as a waste product called lactic acid builds up. This is what causes the burning sensation in muscles and causes them to fatigue more rapidly.
In competition, riders are very aware of their own physical limits and try to use their more limited anaerobic capacity strategically.
Every muscle is made up of two types of fibers. Fast-twitch fibers move 2 to 3 times faster than slow-twitch fibers, but they tire more easily. Fast-twitch fibers, logically, are used for sprinting and quick ascents. Inversely, slow-twitch fibers are used for long rides of moderate intensity.
Most people have half slow-twitch and half fast-twitch fibers in their muscles. However, genetics again plays a role. Some long-distance runners have as much as 80 percent slow twitch fibers, while sprinters tend to have more fast-twitch fibers.
While genetics can certainly play a role in deciding whether a cyclist will be a champion or not, the drive to win and compete also has to be present. Long hours of training and intensive competition require the cyclist to be extremely determined. In addition, competitive cycling requires adherence to details and to finely tuned techniques.
People who commute by bicycle or ride recreationally may not have the extreme determination that a pro cyclist has, but nevertheless cycling provides challenges and rewards to everyone who rides. Most cyclists agree that cycling not only improves their physical health but their mental outlook. A sense of accomplishment and a feeling of independence are feelings every cyclist shares. Perhaps that’s why cycling for many is more than a sport or even a mode of transportation–it’s a passion.