For high-end activewear brands, the biggest challenge in winter apparel development is achieving the perfect balance between warmth and breathability. Consumers expect winter pieces—leggings, tops, base layers, running layers—to protect against cold weather while still allowing heat and moisture to escape during movement. This requirement makes thermal-regulating fabrics a critical component of winter activewear design for Europe, the U.S., and Canada.

In cold weather, the body needs insulation to stay warm, but during training, excess heat and sweat must escape quickly to avoid discomfort. If fabric traps too much heat, the wearer overheats; if it releases too much heat, the wearer becomes cold.

Thermal interlock is one of the most efficient materials for winter activewear because of its dense, double-knit structure. It traps warmth without adding weight, making it ideal for fitted long sleeves, base layers, and sleek winter training tops.

Many high-end brands incorporate engineered mesh zones strategically placed in heat-generating areas such as:

For winter lifestyle and athleisure apparel, brands often choose thermal fleece or soft-knit fabrics. These fabrics prioritize comfort while offering moderate breathability.

Before selecting fabrics for winter collections, brands typically evaluate:

The success of winter activewear depends on achieving the right thermal balance: enough warmth to protect against cold weather, and enough breathability to support movement. Thermal interlock, lightly brushed fabrics, engineered mesh, and soft-knit structures all play unique roles in building well-rounded winter assortments. Brands that combine these fabrics strategically are able to deliver winter apparel that feels warm, dry, lightweight, and polished.