Cycling is a great way to stay active and healthy at any age.
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Choosing the right frame size for a bicycle is based on your body's proportions, not your age. Still, age is an important consideration when sizing a bike, since older riders and children often ride bikes with different frame measurements than bikes for an average adult rider. Some bicycle frame styles are sized to place you in a more upright and comfortable position than others by using a shorter top tube and higher head tube, which is ideal for older riders. A young child also needs special frame measurements, since children's bicycles follow a different measurement system than adult bikes. Use your proportions to determine the right bicycle frame size, but keep age in mind when selecting the ideal frame style.
Selecting the Right Frame Size
A bicycle's frame is sized to your proportions by matching your pubic bone height to the seat tube height of the frame. Your pubic bone height is the distance from your pubic bone to your heel, measured along the inside of your leg. When you take this measurement, wear the shoes you intend to wear while cycling. Once you have your pubic bone height, you can match it to its corresponding frame size using a manufacturer's sizing chart. The top tube height and head tube height can also correspond to your proportions, but usually only custom-built frames allow you to get specific top tube and head tube sizes.
Determining Seat Height
The best way to get fitted for a bicycle at any age is to visit a professional at a bike shop. If you can't visit a bike professional, you can determine your ideal seat height by mounting the bike and leaning up against a wall. Place your feet on the pedals and drop one foot down so that the pedals are perpendicular to the floor. If your leg is perfectly straight, your seat is at the right height. If your seat is too low, it can cause a painful burning sensation in your knees, especially for older riders with more sensitive joints. Take your time getting this measurement just right.
Determining Stem Length
Now that you've got your seat set at the right height, you'll need to select a properly sized stem, which connects the handlebars to the bicycle's frame. A shorter stem will place you in a more upright and comfortable position, since you won't have to reach very far forwards to hold the handlebars. Shorter stems are best for older riders with weaker lower-back muscles. If you can't determine what stem size is ideal for you, get a stem with a hinge so you can adjust the position of the handlebars until you find your ideal position.
Bikes for Older Riders
Some frame styles are better suited to the ideal position an older individual needs to be comfortable. Hybrid bicycles and comfort bicycles are designed with the short top tubes and upright riding position that is most beneficial for low-speed riding. There are also frame styles that make it easier to get on the bike. A mixte or step-through style frame gets rid of the top tube entirely, allowing you to easily get one foot on either side of the bike so you can get on without a struggle. Finally, recumbent and semi-recumbent frames let you sit back and relax while riding, which is much more forgiving to riders who struggle with a traditional bicycle seat.
Bikes for Younger Riders
Children's bikes are much smaller than adult bikes and have a different measurement system to match the smaller proportions of young riders. Since children grow quickly and vary in proportion, children's bike sizes are based on the size of the wheels. These wheel sizes are 12, 14, 16, 18, 20, and 24 inches. As children grow, they progress to bikes with larger wheels until they're ready for the smallest adult bicycles. Since most children can't ride as far adults, a bicycle frame that is close in size will be good enough, even if the proportions aren't perfect. Getting the largest size that your child is comfortable riding is a good way to account for the amount he or she is going to grow.