This is a simple question with a complicated answer, which is often the case in life. The answer to this particular question can be yes, no or maybe, depending on the circumstances. That's not particularly helpful if you're trying to decide whether adding fast bike workouts to your training routine will make you run faster. But here's the bottom line -- if you're a recreational runner, as opposed to an elite competitive runner, sprint cycling is likely to make you faster.
Spinning or Intervals
There are two ways to sprint on a bike. You can sprint in the gym in a spin class, where you ride a stationary bike at a high cadence with low resistance. The alternative is to sprint outdoors by doing interval training, a series of high-intensity rides over short distances with a recovery period between sprints. Either approach strengthens leg muscles, increases your endurance and fitness, and alleviates the pounding you endure while running.
If you're a recreational runner, adding spinning or interval training on a bike can make you faster, according to the Get Fit Family website. There are two fundamental reasons. First, your hip rotation when sprinting on a bike is high, since you are pedaling at a fast cadence with little resistance. Getting your legs moving fast on a bike enables you to get them moving more quickly when you run. Second, bike sprints build up your leg muscles, since pedaling uses more muscle power than a running stride. For a recreational runner, the added leg strength also helps stabilize your knees, which allows a quicker cadence without an increased risk of injury.
If you run competitively, you might not benefit from bike sprints. A further buildup in your leg muscles, which are already exceptionally strong, might result in more muscle mass in your quads and glutes and increase your overall weight. Elite runners don't need excessive weight -- it slows them down. On the other hand, runners with certain physical limitations -- for example, a troublesome Achilles tendon -- might not be able to do enough high-intensity running to improve their speed. Substituting high-intensity cycling can lead to improved performance when you run, according to the Competitor website for runners.
Cross-training is often touted as an excellent way to improve your athletic performance. You work different muscle groups, lessen the possibility of overuse injuries and alleviate workout boredom. REI cites cycling, stair climbing, cross-country skiing and aerobic dance classes as examples of cross-training activities for runners. Runner's World advocates mixing in the other two triathlete activities -- cycling and swimming -- into your workouts. If you are a recreational runner, cross-training is likely to improve your running ability. If you are an elite athlete, certain cross-training activities are likely to help your performance by giving your legs a break and helping to avoid injuries. But sprint cycling might not be the best form of cross-training for you.
Jim Thomas has been a freelance writer since 1978. He wrote a book about professional golfers and has written magazine articles about sports, politics, legal issues, travel and business for national and Northwest publications. He received a Juris Doctor from Duke Law School and a Bachelor of Science in political science from Whitman College.