This is from the Virtual Trainer Email... ;)
Cross Training can be a helpful addition to your 3-Day training program. It allows you to build muscle endurance while decreasing overuse injuries. Remember the 10% rule: you should increase your activity 10% each week in order to give your body time to recover between your training walks. It is possible to do too much, too soon. Pace yourself and pay attention to how your body feels at all times.
While walking is the most important preparation, other types of training that will help increase your stamina and strengthen walking muscles include:
• Elliptical Trainer
• Stair Stepping
Strength training through resistive bands or low weights is also an important part of your training program because it can build muscle. Muscle increases your endurance and burns fat better than fat does. It need not be an extensive weight lifting program. Interval or circuit training (i.e. Curves classes) alternate aerobic activity with strength exercises. They can be an efficient complement to your training program.