What to wear

Dress as if it were about 10 °C warmer than it is: you should feel a little cool at the start, because running heats you up fast.

• Choose technical fabrics (polyester, merino wool) that wick sweat away; avoid cotton, which stays wet, chills you and chafes.
• Above 15 °C: shorts and a T-shirt. From 5 to 15 °C: long sleeves or a light layer, shorts or tights. Below 5 °C: tights, two or three layers, hat and gloves.
• Layer up: a base layer against the skin, an insulating layer if it’s cold, a light windproof or waterproof jacket on top.
• Seamless running socks and anti-chafing balm help on long runs; add reflective details after dark.