Your goal: five 30- to 75-minute aerobic workouts per week. Do any of the following activities.
Running or power-hiking
30 minutes, building to 60 to 75 minutes
Once a week for 30 to 75 minutes with a pack (start with 10 pounds and build to trip weight or 5 pounds more). Viesturs does this workout after strength training, but you can do it on a separate day.
Start each session with a 10-minute warmup on a rowing machine (Liljeblad’s favorite because it involves the whole body), stationary bike, or stair climber. Your goal: core exercises three times a week, upper body and legs twice a week. For all exercises, use a 4- to 15-pound medicine ball or 5- to 20-pound dumbbells, depending on your fitness level.