Icon Health & Fitness has bought Altra Footwear, a developer of minimalist shoes, for an undisclosed amount. Altra Footwear was founded in 2009 by runners, and claims to have created the first “zero-drop” footwear line, meaning that the heel is the same height as the toe. Most running shoes have a heel twice as high as the toe, and Altra alleges that running in these “high heels” can be damaging to the feet. Altra's core running shoes, outdoor shoes and minimalist shoes are fully cushioned and gender-specific. The new line was unveiled at the Outdoor Retailer show this month in Utah.