Pete Swenson, coach of the U.S. Ski Mountaineering team, provides a cross-country skiing workout to burn over 700 calories per hour. The workout focuses on core exercises like crunches, upper body exercises like lat pulldowns, and 30 minutes of cardio like treadmill sprints. Swenson recommends proper technique of bending at the waist and pushing through your heel to transfer weight efficiently with each stride. The summary highlights the high-intensity cross-country skiing workout targeting the core, upper body, and cardio to burn fat effectively.