At GSER, we love our Trail Crews almost as much as we love our runners. You’re the most colourful, the loudest, and absolutely essential to the incredible atmosphere of race weekend!

But you’re not just there to cheer – you’ve got a mission: get your runner to that finish line.

Step 1: Know the Plan

Your first job? Read the Support Crew section in the GSER 2025 Runner Guide, released one month before the race. It’s packed with key details you’ll need for a smooth, successful day.

Step 2: Check the Crew Page

Want to know where to go, how to get there, and what to expect? The Trail Crew page is your best friend—loaded with crew-specific info, maps, and tips.

• (P) = Pacer access and (C) = Crew support is allowed at that Aid Station.

It has to be one of the most iconic ultramarathon distances: 100 miles. Some of the most famous ultras in the world are 100-milers (such as the UTMB® –  Western States Endurance Run and GSER), so it’s easy to see why the distance captures the imagination of so many runners.

Running 100 miles is no small undertaking, so as with any other running goal, it’s crucial to have a plan.
That’s not just a great training plan (more on that in a minute), but also a plan for hydration, fuelling, sleep, strength work and general self-care.

We’ve asked international athlete and UKA-certified coach Sarah McCormack to write a training plan to help you prepare for GSER 100-miler. The plan is aimed at experienced athletes, who have previously run an ultra – although it doesn’t matter whether you’ve run a 100-mile race before.

We hope you enjoy it and that you race strongly – happy running!

BEFORE YOU START