How much running is too much? A new take on injury risk for runners

Why is this study important?

Running continues to grow in popularity worldwide—celebrated for its health benefits and accessibility. Although it also comes with a downside: the risk of injuries. Up to half of all runners report an injury each year, many of them overuse-related. Traditionally, clinicians and coaches have focused on gradual increases in weekly mileage and workload ratios (like the acute:chronic workload ratio, or ACWR) to reduce injury risk.

However, these traditional approaches are overlooking something crucial. Despite widespread use in science and wearable technology, these weekly-based calculations may not accurately reflect the moment-to-moment load decisions runners actually make. In practice, injuries may strike more “suddenly” for instance after a single ill-judged running session that is longer than usual. Equipped with this novel hypothesis, the present study offers a paradigm-shift by focusing on single-session spikes in running distance, rather than week-to-week trends.