Become a member to unlock this story and receive other great perks. Already have an Outside Account? Sign in All Access15% off New Year Sale $7.02 / month* A $500 value with everything in the Print + Digital Plan plus 25+ benefits including: Member-only content from every title in the Outside network like Outside, SKI, Climbing, and more Annual gear guides for backpacking, camping, skiing , climbing, and more Gaia GPS Premium with hundreds of maps and global trail recommendations, a $39.99 value Premium access to Outside TV and 1,000+ hours of exclusive shows Exclusive discounts on gear, travel, and race-entry fees Annual subscription to Outside magazine Join Outside+ Print + Digital50% Off New Year Sale $2.00 / month* Annual subscription to Backpacker magazine Access to all member-exclusive content and gear reviews on Backpacker.com Ad-free access to Backpacker.com Join Backpacker *Outside memberships are billed annually. Print subscriptions available to U.S. residents only. You may cancel your membership at anytime, but no refunds will be issued for payments already made. Upon cancellation, you will have access to your membership through the end of your paid year. More Details Videos Video loading... Alpine Fitness Save Your Knees: Poor Man's Leg Curl Share this Facebook Icon Twitter Icon Email Icon Join Backpacker Create a personalized feed and bookmark your favorites. Join for free Already have an account? Sign In Join Backpacker Create a personalized feed and bookmark your favorites. Join for free Already have an account? Sign In In this first of three videos, mountain performance coach Jason Antin teaches one exercise for preventing knee pain so you can crush the trail.