Lululemon unveils temperature-regulating Ventscape Run Vest

The new cold-weather running layer is designed to respond to changing body temperature as runners move through different levels of effort.

Published on Nov 12, 2026 by Grace Curran

Cold-weather runners know the constant pinball of layering up for a run. One minute you’re freezing, the next you’re overheating, and before long, you’re cold again.

Enter lululemon’s newest run vest: Ventscape.

With Ventscape, the company is rethinking how insulation and ventilation can work together to regulate temperature throughout a run.

Rather than simply maximizing warmth, the new construction is designed to maintain a more consistent thermal experience as the body’s needs change with exertion.

Rethinking running insulation

At the core of the vest is PrimaLoft® ThermoPlume®+, a synthetic down alternative designed to trap warm air without adding bulk. Strategically placed mesh panels complement the insulation by releasing excess heat and moisture as the body warms up.

To develop the technology, lululemon’s Product Innovation lab put the construction through more than 250 hours of testing and 2,500 kilometers of validation across laboratory and real-world conditions.

The team used digital simulations to test different combinations of insulation and mesh, helping determine where the vest needed more warmth and where it needed more ventilation. Prototypes were also tested on thermal mannequins to see how well the vest retained heat in windy conditions at simulated running speeds.

Through a carefully engineered insulation-to-mesh ratio, Ventscape is designed to balance warmth and breathability. It’s essentially a case of addition by subtraction.

All-Star Testing Team

lululemon ambassadors, including ultrarunner Leah Yingling, Olympic middle-distance runner Nikki Hiltz, and F1 champion Lewis Hamilton, voiced what they wanted from cold-weather running apparel, helped shape the vest’s fit and construction, and tested prototypes in both cold-chamber and outdoor conditions.