From The Ergoweb® Learning Center

Biking Biomechanics- Fitting Task and Equipment to the Rider

Biomechanics is the study of the mechanics of a living body, especially of the forces exerted by muscles and gravity on the skeletal structure. In occupational ergonomics, biomechanics is used to improve the design of work tasks and areas to better suit human abilities. Outside of the workplace biomechanics is big business, especially for sporting equipment manufacturers who are looking to offer their customers even the slightest competitive edge.

So, what do biomechanics and ergonomics have to do with making a faster bike rider? A whole lot, according to bike manufacturer, Softride. Ergonomics is about fitting the tasks and equipment to the user, not the other way around. In the case of biking, the environment would be the type of biking someone wanted to perform. This might be road racing, mountain biking, casual riding, or multi-sport riding. Just like in the workplace, it is important to identify what the environment will be so that appropriate tools and equipment can then be implemented. The equipment, in this case, would be the actual bicycle. To have the best performance, the rider needs to have a bike that fits his or her body. A good fit on a bike will equate to a better and safer performance with less fatigue. A hand tool that fits a worker will also produce the same results.

The best way to have a tool or piece of equipment fit a user would be to have it custom made to that person’s anthropometry and ability levels. Unfortunately, customization is usually too expensive for most workplaces and all but the most die-hard bike riders. If customization is ruled out, the next cost effective option is adjustability.

As workplaces have become more aware of ergonomics in design and the significant cost of musculoskeletal disorders (MSDs), we have seen more adjustability present in working areas, tools, and design. But, is buying a tool in different sizes enough? How much adjustability does it take to see increased performance? When the human body is concerned, adjustability can be measured in just a few centimeters or degrees.

To give you an idea of the precision fit we are talking about here, research at Softride showed that adjusting the angle of one bike seat more than about 5 degrees (between 76 and 81 to the horizontal) would negatively impact a person’s performance. Likewise, performance can be enhanced by adding or decreasing one centimeter increments in the handlebars.

While we are not likely to see this degree of adjustability in the workplace, it is encouraging for all ergonomists to know that adjusting a back posture by 15 degrees to make it more upright can produce results. Likewise, while a foreman or supervisor might not immediately see the difference between a small and large sized tool, the operator using it most likely will.

Read more about Biking and Biomechanics in the April, 2002, edition of The Ergonomics Report