Focus: cardio + plyometric strengthening
Find a long section of trail with a steep incline. Start with 15-second intervals followed by 1-minute rests. Jump up the trail six times as if you're doing a standing broad jump. Rest. Drop into a tuck; shuffle left, shuffle right (watching out for logs, rocks, and such). Rest.
For each interval, try something different: bounding uphill, jumping on one leg, tuck jumps, or frog jumps. Davenport builds to 45 minutes, doing intervals of 2 minutes with 4-minute rests. "You're making multidirectional changes in space and absorbing gravity and pushing up against it, says Keller. "That's how you enhance and increase agility on the slopes.