Cold knees when cycling in winter: Shorts or not? - Are knees at risk of getting cold when riding a road bike?

Question from TOUR reader Benedikt J.: Even in winter, I'm always warm. My toes, fingers and neck need protection, of course, but to make sure I don't get too warm overall, I ride in shorts. A colleague told me that it's not good for my knees. But I've never had any problems with my knees. Are your knees at risk from the cold?

Answer from Dr Christian Merkl: If body tissue is exposed to the cold for a longer period of time, the core body temperature and the temperature of the peripheral limbs will drop depending on heat loss and heat production. If you ride in cycling shorts even at low temperatures, you risk not only peripheral damage to the knee joint region, but also hypothermia of your entire body. The knee joint in particular, which is poorly covered and insulated by muscle mass, is exposed to cold, wet conditions and wind (wind chill effect), meaning that initial damage can be expected even after short training rides.

Without wanting to describe the complete process of frostbite: If the tissue temperature drops, this first leads to reduced blood flow in the affected tissue - less blood means less oxygen, which in turn reduces performance. In the next phase, cold shivering occurs and the hypothermic tissue consumes more oxygen and energy. In the area surrounding the unprotected knee joint, inflammation can develop at the tendon insertions (above and below the kneecap, quadriceps/patellar tendon) and the knee joint capsule. I have often seen chronic inflammation of the tendons (e.g. patellar tendinitis) as a result. From temperatures below ten degrees, I can only recommend long trousers, especially at higher speeds. If you want to adapt flexibly to the temperature, you can opt for the "onion look" and carry leg warmers, arm warmers or even additional clothing in your rucksack. After all, if you are hypothermic and/or suffer initial localised cold damage, you risk a longer training break due to colds or localised complaints.