At the moment this post goes live (at 5:30 a.m. ET on Saturday, August 4th), I’ll be joining 5,500 kindred spirits on an amazing and long two-day bike ride. And I’ll be asking myself, Why am I doing this again?

Living in Massachusetts, it doesn’t take long before you run into the Pan-Massachusetts Challenge. Thousands have ridden it, volunteered for it, or cheered it on. Last year, more than 230,000 people made individual donations to the Dana-Farber Cancer Institute through the Pan-Mass Challenge, with 100% of the donations going to the DFCI (it’s the most efficient athletic fundraiser possible). The first weekend in August, many roads in Massachusetts fill with cyclists and cheering crowds as the riders roll through. The most recent extension of the event has been Kids  Rides, where tykes — from toddlers to early teens — can ride and raise money throughout the spring and early summer. These kids raise a few hundred thousand dollars each year, and are amazingly intense in their efforts both on and off the bike.

So at 5:30 this morning, I’ll begin riding my 11th consecutive Pan-Mass Challenge. The full route is a two-day, 192-mile ride from Sturbridge to Provincetown. The goal is for the 5,000+ riders to raise $36 million for the Dana-Farber Cancer Institute. (If you donated this year, thank you!!) It’s an amazing cause that extends far beyond the weekend of the ride. A stream of related events involve patients, families, and riders throughout the year in a virtuous blend of sport, hope, work, funding, and determination.

During this past decade, my sister has overcome breast cancer; I’ve ridden for a number of Pedal Partners (kids with cancer); and I’ve seen friends overcome and fall prey to cancer. Cancer patients now face a vastly better set of odds than they did when the Pan-Mass Challenge started in 1980. The ride has raised $338 million to fund cancer care and research so far.

So why are we doing this again? Is it for the friend and fellow rider who just relapsed? Is it for the relative who was just diagnosed? Is it for the kid who will be a cancer survivor for many decades now?

We ride for them, and for thousands of others. We ride for all the reasons you’ll see in this video.

Have a great weekend. See you Monday.