Moisture-wicking shirts pull sweat away from your skin and spread it across the fabric surface so it evaporates faster—helping you stay drier, cooler, and more comfortable during training and daily wear. Synthetics like polyester and nylon excel at wicking and quick-dry performance, while merino wool blends add natural odor resistance and comfort. For a primer on how wicking works and choosing fabrics by activity and temperature, see REI’s base layer guide (synthetics wick and dry fastest; merino shines for odor...