Decent selection of road, triathlon, and mountain bikes. Rentals also offered along with single day and multi day tours. Road bikes and mountain bikes range from $40 for four hours to $500 for two weeks, depending on the type of bike you're renting.
Las Vegas Premium Outlets Mall North (closer to the Strip) offers a wide variety of stores with deeply discounted prices. We mention it here because among the many traditional clothing retailers are also factory stores from Nike, Adidas, Reebok, Asics and Puma.
Performance Footwear stocks New Balance shoes and other top athletic brands. The store is about 8 miles from most of the hotels on the strip.
One of the best pure run stores in Las Vegas. Top shoe brands are offered here (Asics, Brooks, Adidas, etc.) and plenty of apparel too. Check out the shop's website for more deets and directions.
