QUESTION: I run with bare legs when it's in the 30s, but all the experienced riders around here wear tights even when it's much warmer. What's the rule for covering up? -- Blaise P.

COACH FRED: A cyclist's knees are directly exposed to cold air. The danger is much more pronounced compared to running because the bike's greater speed generates more wind chill.

The standard advice is to wear tights or leg warmers whenever the temperature is below 65 degrees. Covering up protects your knees and keeps your muscles warm. There's no downside -- it's not the time of year to work on your tan, anyway

Be especially careful during warm spells after early-season snowfalls. The thermometer may say you don't need to cover your legs, but snow on the roadside creates a microclimate of colder air at knee height.

If in doubt around the mid 60s, roll up a pair of knee warmers and carry them in your jersey pocket. Pull them on if the temperature drops or you encounter a long descent where high speed increases the wind chill.