Running app Runna has launched a new feature that automatically adjusts training sessions based on local heat and humidity, aiming to help athletes cope with increasingly extreme summer temperatures. Called Adapt for Heat, the tool typically reduces recommended running speeds when conditions become uncomfortably hot, using an algorithm personalised to each user's existing training plan and prior performance data.

The feature also includes a colour-coded hourly weather forecast, helping users spot the coolest and hottest parts of the day to better time their workouts. It is available immediately to all subscribers. Runna, which was recently acquired by Strava, is also preparing two further updates for August: "Upcoming Plans", allowing users to schedule multiple training plans up to a year ahead, and a revamped "Post-Race Recovery Plan" offering structured, personalised recovery guidance after races.