Hey Thumper, good luck on those three day walks! Great cause to support and you get the added health benefits of working out. Sounds like a win-win to me. My kids are competitive racewalkers (believe it or not, it's an Olympic sport) and I'm a former cross country coach, so I'll give you some ideas to get you started, but if you have any questions, just holler. Are you starting from scratch or do you already walk?
Focus on getting at least one longer walk (15+) in every week, but build up to it gradually. General rule is your weekly mileage should only be 10-20% more than the previous week, but what amount that is depends on where you're starting from and how much time you have to prepare. Moderate length to short walks the other days of the week, with one or two days off from walking. You could run, rather than walk, if you want to get done more quickly. Running uses more lower leg muscles (arch of the foot, calves) and running will employ your upper leg muscles (quads, hamstrings) more - but the cardio benefit will be the same. Bicycling or elliptical will give your walking muscles a rest, but also give you a good cardio benefits.
Core exercises (planks, crunches) will help stabilize your body and make you a more efficient walker. Some upper body weights (low resistance, high reps) will keep your arms from tiring over the distance. 2-3 times a week for these two things is ideal, but time becomes a factor when you start adding additional training and it'll be the walking that should be your priority.
Since I'm guessing you're not going for time, the important thing is to gradually build up your endurance - that way you won't have ginormous blisters on the big day or have muscles that are screaming at you to stop by the second day. Building up and maintaining a distance base will also help prevent injury.
Good shoes = very important. When they lose their cushioning or support, it's time for a new pair.
Focus on getting at least one longer walk (15+) in every week, but build up to it gradually. General rule is your weekly mileage should only be 10-20% more than the previous week, but what amount that is depends on where you're starting from and how much time you have to prepare. Moderate length to short walks the other days of the week, with one or two days off from walking. You could run, rather than walk, if you want to get done more quickly. Running uses more lower leg muscles (arch of the foot, calves) and running will employ your upper leg muscles (quads, hamstrings) more - but the cardio benefit will be the same. Bicycling or elliptical will give your walking muscles a rest, but also give you a good cardio benefits.
Core exercises (planks, crunches) will help stabilize your body and make you a more efficient walker. Some upper body weights (low resistance, high reps) will keep your arms from tiring over the distance. 2-3 times a week for these two things is ideal, but time becomes a factor when you start adding additional training and it'll be the walking that should be your priority.
Since I'm guessing you're not going for time, the important thing is to gradually build up your endurance - that way you won't have ginormous blisters on the big day or have muscles that are screaming at you to stop by the second day. Building up and maintaining a distance base will also help prevent injury.
Good shoes = very important. When they lose their cushioning or support, it's time for a new pair.
