Any mountain sport like hiking or skiing is basically a controlled fall down during descent. This is the opposite of the type of muscle contraction performed while climbing or ascending. Understanding this is critical to the preparation for these mountain activities. Eccentric training has been termed “negatives” in the gyms and weight lifting communities for decades. When designing strength and conditioning programs for athletes we expose them to multiple types of resistance speeds, resistance loads, and put an emphasis on concentric (positive) and eccentric (negative) muscle contraction. To provide a basic example, while you’re slowly lowering toward the ground during a basic squat, your muscles are lengthening in an eccentric contraction. When standing back up with the load, your muscles are shortening in a concentric contraction. When skiers or hikers only train concentrically they fail to accomplish the basic sports specific training required to be successful. They pay the price with fatigue and knee pain after descending and are left wondering why this happened.