Treadmill running

The treadmill is a good substitute for running outside. Set the incline to 1 % to make up for the missing air resistance and match outdoor effort.

• The 1 % applies from about 10 to 18 km/h; at slower speeds it makes little difference.
• The same pace often feels harder indoors because of the heat: use a fan, drink, and run by effort or heart rate.
• It is ideal for intervals at an exact speed, and for climbs: 4 to 8 % incline imitates a hill.
• Don’t hold the handrails, and look ahead rather than at your feet.
• Indoors, the Apple Watch estimates distance from your movement, calibrated by your outdoor GPS runs, so it can differ a little from the treadmill’s display.