The 1% Rule: Incline on Treadmills Explained — image accompanying Canadian Running's report. Image accompanying Canadian Running’s report; reduced and presented for news commentary with the attributed report. View the complete source report.
The 1% rule suggests using a one percent incline on treadmills to match outdoor running energy costs. This stems from a 1996 study, which found a four percent lower energy cost on treadmills.
Brittany Moran, a marathoner and coach, explains that wind resistance outdoors increases energy cost, making treadmill running feel easier. For faster paces, a two percent incline is recommended. Read more culture coverage.
The rule applies to paces faster than 5:42 per kilometer. It doesn't replicate all outdoor demands, so varying incline and pace can help. For race training, inclines help match outdoor conditions. Related: Osteoarthritis Diagnosis Doesn't Necessarily End Running Career.
This original Runner World brief is based on reporting from Canadian Running. Visit the source for its complete reporting, context and any later corrections.
Reader questions
Questions about this report
What should runners know about The 1% Rule: Incline on Treadmills Explained?
Understanding the science behind treadmill inclines for runners. The 1% rule suggests using a one percent incline on treadmills to match outdoor running energy costs. This stems from a 1996 study, which found a four percent lower energy cost on treadmills.
When did Runner World publish this culture brief?
Runner World published this brief on September 15, 2026. The underlying Canadian Running report was dated September 14, 2026.
Where can readers find the complete original report?
This summary is based on reporting from Canadian Running. The attributed source link in the article leads to the publisher’s complete report.
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