Why It's Time to Stop Counting Mileage

Why It's Time to Stop Counting Mileage

Most runners use the same basic measurement to determine their running progress: “How many miles did you run last week?” Despite dozens of new tracking products on the market, runners still use this old-school method.

However, a new study in the Journal of Orthopaedic & Sports Physical Therapy  has found that purely evaluating mileage may not be the best or healthiest way to look at running ability. The authors are credible scientists, physical therapists, and coaches, and runners on their own.

The researchers emphasized that running distance is only one aspect contributing to training stress, and they believe it’s important to look at alternative approaches to quantify and monitor training stress.

Why Mileage Doesn’t Tell the Whole Story

The paper first addresses why mileage isn’t a complete way to look at running progress or ability. The reasons is that the distance you cover does not always account for how much stress you’re putting on your body. An easy 5 mile trail run is very different from 5 miles worth of sprints on a track. Plus, that 5 mile run could be much harder on your body if you’re tired from previous training, compared to when you are fresh.

The researchers discuss how training stress is “influenced by external (i.e., application of mechanical load) and internal (i.e., physiological/psychological effort) training load factors.” Common external load factors include volume and pace, while physiological internal load factors include session ratings of perceived exertion, heart rate, or blood lactate level.

In order to really understand how much stress you’re putting on your body and how much fitter you’re getting, you need to calculate all factors. Wearable technology that quantifies external load metrics can help you gain a better understanding of how your body is performing.

The paper compares three different scenarios that each involve 10K of running: an easy run on a soft trail in cushioned shoes when fresh; a similar easy run when tired; and a track session of 10 x 1,000 meters in rigid spikes. The paces represent an elite runner: 6:00 miles for the fresh easy run, just under 7:00 miles for the tired run, and 2:45 per kilometer (4:25/mile pace) for the intervals. For the tired run, the runner’s average cadence drops from 180 to 177, but the total time is greater, meaning that he takes more steps in total. For the track session, cadence jumps to 198, but the time elapsed is way less. 

Looking At Overall Running Effort Can Reduce Injury Risk

When runners are obsessed with hitting mileage goals, and don’t take into consideration the stress they’re putting on their body, they put themselves at higher risk of injury.

A more holistic view of running effort and stress will allow runners to be more thoughtful in their body’s limits and not perform risky training behaviors.

Instead of focusing on hitting 50 miles per week, for example, runners should evaluate how many of those miles are intense training sessions, and how many are gentle runs.

In an evaluation of this study from Outside magazine’s Sweat Science column, author Alex Hutchinson explains that more studies need to be done to create a better method for runners to understand their force and stress. Wearable tech has advanced so much in recent years that it’s possible to get detailed biomechanical information from ordinary consumer devices. And with further development, these devices may be able to narrow it down and estimate the load on individual parts of the body like shin bones and Achilles tendons. 

Do you calculate your weekly mileage? If you’re looking for ways to improve your mileage, or to better understand how much stress you’re putting on your body, schedule a telehealth appointment with Oregon Running Clinic. Dr. Davis can help you understand your gait and force, and recommend exercises to help you strengthen key muscles and improve your running ability./