You may be tempted to be an MS Challenge Walk speed demon, but in the long run (no pun intended), you need to go at your own pace.
When you set out on the MS Challenge Walk, you'll be in the company of hundreds of other walkers. Sometimes someone will zip up from behind you and leave you in their dust; other times, you'll come up to someone and politely pass them as you go on your merry way. In either case, there's a lesson to be learned: no matter what everyone else around you is doing, you need to go at a pace that suits you.
The average walking speed is 3-4 MPH, which doesn't sound like a vast range, but consider: between the lower boundary and the upper one is an increase of 33%. If your boss asked you to work 33% harder, or to work an extra 13 hours a week, you'd rebel! And so will your body if you make it work harder than it wants to.
I learned this lesson the hard way. I got to the Hyannis Village Green too late for the opening ceremonies and thus started the walk at the back of the pack. Determined to make up the time and catch up to my fellow walkers, I set myself an ambitious pace. As a result, the first night of my third MS Challenge Walk was the first time I'd ever thought to myself, "I might not be able to finish this." My body was that sore.
If you're concerned about finishing the walk in a certain time, don't be. It's not a race, and there's no prize for finishing first. If you start your walk as soon as the route opens, there's plenty of time to complete it at a comfortable speed before the support crew closes up shop and brings everyone home.
Marathon runners learn to set a pace, saving their energy for the long haul. The same is true for walkers. One definition of "marathon" is "any contest, event, or the like, of great, or greater than normal, length or duration or requiring exceptional endurance." Given the undertaking you each have dedicated yourselves to, I think it's entirely appropriate to wish you a successful and safe MS Challenge Marathon.