Steep hills, with a 10 to 15 percent gradient, have a bigger strengthening effect but are more stressful on calves and Achilles tendons. Start on hills of 4 to 8 percent before progressing.
Credit: Getty Images
Powered By ZergNet
Sign up to receive the Men’s Journal newsletter and special offers from MJ and its marketing partners.
56 Perfect Things
Tech, Tools, Toys, & the Hottest New Gear
Plus: The Deadly Thrill of BASE Jumping
ON NEWSSTANDS NOW