Treadmill Miles Vs. Road Miles

If you enjoy running and are considering trading in your road miles for some distance on the treadmill, be aware of the differences between each activity. Road and treadmill workouts have different benefits in terms of the improvements to your health and running performance.

Function

When you run on the road, your legs create propulsive forces in order to carry your center mass forward, but on a treadmill, your legs, which are in essence moved by the belt, constantly reposition themselves. During treadmill running your legs are not used to generate propulsive forces, but rather to maintain balance and keep your center mass static.

Significance

As Paula Coates observes in "Running Repairs: A Runner's Guide to Keeping Injury Free," some runners claim that treadmill running allows you to hone in on certain aspects of training with precision, including maintaining a consistent pace or setting the exact inclination of a hill climb. Though these claims hold some truth, the reality is that, for the competitive road runner, you have no better way to improve your distance or speed than by pounding the pavement.

The Facts

In a study led by British physiologist L.G. Pugh that measured the relationship between running speed and energy expenditure, track runners showed a significantly higher level of oxygen consumption than that of treadmill runners. This was attributed to needing more energy to overcome the effect of air resistance, especially at higher speeds.
In a study conducted by the American College of Sport Medicine that investigated the relationship between temporal factors and vertical and horizontal velocities of the center of gravity, findings showed that treadmill running at higher speeds not only increases stride length--as runners attempt to keep their feet on the belt for longer in order to maintain stability--but it also lacks the physical demands associated with propelling the body forward when running on road. Thus treadmill training might in fact have adverse effects on road running technique.

Considerations

While these studies provide evidence that treadmill training is not as effective as road running for the competitive runner, it's physical and health benefits should not be overlooked. According to Rick Morris, author of "Treadmill Training for Runners," not only does it stimulate cardiovascular and aerobic activity, it's also less damaging to your joints because most treadmill surfaces are softer than those of asphalt or concrete.

Solution

If you're looking to improve overall health and physique, or wanting to add another drill to improve your leg speed and reflexes, then use a treadmill. If you wish to focus your efforts on boosting your running performance, stick to the road. Indisputably, road miles will give you more of a workout for the time committed to your training, particularly developing your calves and hamstrings more effectively.