Hopefully each crew member has been exercising on a regular basis, at least three times a week for no less than an hour each session. If they have not, try revisiting the crew member contract that was discussed in part one of this guide. Once you have built up your aerobic/cardiovascular ability, weight lifting is a good next step to build strength needed for hauling a 45- to 55-pound pack around rugged mountainous terrain. Again, lower body muscles are more beneficial for backpacking than upper body but a strong core/abdomen will help your entire body stay strong and help prevent injury on the trail. Some core exercises include crunches and sit-ups and doing these for 20 minutes three times a week will help you get into great shape for your Philmont trek.