Appetite for construction
To meet these very variable requirements, bike wear manufacturers use different designs of jerseys. Because although there isn't one perfect shirt for everything, there doesn't have to be: the sensation of cold on the one hand and the heat balance on the other varies greatly from cyclist to cyclist. And in addition to all individuality, the daily fitness level of each individual is also taken into account. What seems to be the perfect clothing combination today may be perceived differently tomorrow, despite the same weather conditions. On top of that, it differs slightly from cycling discipline to cycling discipline.
So how do I find the right jersey?
Basically, with winter jerseys, we cyclists can choose between unlined and lined mid-layer apparel. In both cases, air is "stored" within the layer of clothing and heated by the body. With the padded textiles there is more air, with the unpadded ones less. In technical jargon, this is referred to as insulation performance.
As a rule of thumb, the higher the intensity, the less insulation I need. On a Road bike, for example, padded jerseys - worn solo or under a jacket as a mid-layer - only make sense when it is really, really cold. In the city, on the other hand, for short distances, when the body only reaches temperature shortly before the destination or when you can expect standstill times in stop-and-go situations, a mid-layer with the right padding can be quite useful. Long MTB descents after a sweaty ascent, require good ventilation uphill and windproofing downhill. Padding? Rather suboptimal.
In the field of padded gear, manufacturers rely on synthetic fibre fillings: Polartec Alpha, for example, is a filling fibre fleece that has very good insulation values in relation to the filling quantity, but at the same time only slightly impedes the removal of sweat moisture. The same can be said about certain, rather thin Primaloft linings. Basically, the thicker the layer of filling material, the better the heat retention capacity. But also the worse the water vapour transmission. In other words, if you are under increased physical strain over a longer period of time, you will end up stewing in your own juices in thickly lined clothes, which can be dangerous, because a sweaty body also cools down more. It is therefore a logical consequence that down fillings haven’t found a hold in cycling. The insulation performance of down is in a sense "too good". In addition, down virtually attracts moisture, but then clumps together - and the insulating effect stops.
Mid-layer jerseys without padding usually use a special material structure for heat retention in order to keep the desired air cushion close to the body.