Study Challenges 1% Treadmill Myth for Indoor Running — image accompanying Marathon Handbook's report. Image accompanying Marathon Handbook’s report; reduced and presented for news commentary with the attributed report. View the complete source report.
Marathon Handbook reports on a study comparing treadmill and outdoor running. Twelve national-level male runners tested at various speeds. Oxygen consumption and energy cost differed between surfaces. The study suggests treadmill paces may not match outdoor paces.
The study measured oxygen consumption, cost per kilometer, and energy use. Results showed overground running had a higher energetic cost. This challenges the 1% treadmill myth. The study recommends calibrating by effort or heart rate instead of a universal incline correction. Read more everyday miles coverage.
Treadmills remain useful for controlled training. But paces may differ indoors and outdoors. Runners should track progress consistently. Completing race-specific work on the intended surface is advised. The study does not suggest raising the treadmill incline further. Related: Study Finds No Performance Boost from Probiotics in Runners.
This original Runner World brief is based on reporting from Marathon Handbook. Visit the source for its complete reporting, context and any later corrections.
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Questions about this report
What should runners know about Study Challenges 1% Treadmill Myth for Indoor Running?
Research shows outdoor running costs more energy than treadmill running at 1% incline. Marathon Handbook reports on a study comparing treadmill and outdoor running. Twelve national-level male runners tested at various speeds. Oxygen consumption and energy cost differed between surfaces. The study suggests treadmill paces may not match outdoor paces.
When did Runner World publish this everyday miles brief?
Runner World published this brief on August 20, 2026. The underlying Marathon Handbook report was dated August 20, 2026.
Where can readers find the complete original report?
This summary is based on reporting from Marathon Handbook. The attributed source link in the article leads to the publisher’s complete report.
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