If you haven’t run with a pacer before, they're hard to miss.
Look out for the runners with brightly coloured flags displaying their target finish times on their backs in your start wave.
Big Half veteran Amber French (pictured above on the right) will be leading one of the 2:30 pace groups. She will be on the Start Line for the fourth time, but with one important difference: this will be her first year as a pacer.
Amber trains with Runners High, an inclusive London-based running community for women and non-binary people. The Big Half is her favourite event on the running calendar, thanks to its unbeatable atmosphere and route that gives runners a taste of the TCS London Marathon.
We caught up with Amber to find out what you should look out for on Event Day.
“I love the course. The vibes are always amazing and it gives you a flavour of the London Marathon,” she says. “Running across Tower Bridge is incredible. You can’t really get that experience anywhere else unless you're running the marathon. As someone who avidly follows athletics, it's exciting to think that runners like Alex Yee and Sifan Hassan have raced on the same streets.”
If it’s your first Big Half, Amber is quick to reassure anyone worried about the course profile.
“Don't get put off by the little hill at Mile Two. The first time I did it, I remember thinking, 'Everyone said this was flat!' But honestly, that's basically the only hill, and it's over within a few kilometres.”
The course is largely flat and fast, with a total elevation gain of 218 feet. There is a gentle incline before Tower Bridge and another slight rise in the final 500 metres before the Finish Line.
Meet the run crews joining you on Event Day
Also, don't be alarmed if your watch starts behaving strangely between Miles Four and Six.
“There's a section around Canary Wharf where GPS can go a bit funny,” says Amber. “Following a pacer will keep you perfectly on pace the whole time. It is really reassuring.”
After Canary Wharf, be prepared for a short cobbled section in Wapping. By this point, you'll be closing in on Amber's favourite moment of the course: Tower Bridge.
“Definitely soak up the atmosphere on Tower Bridge,” she says. “It's around the halfway point and the crowds are always amazing. It's one of those moments you really want to take in.”
Last year, Amber followed Pace Team Co-ordinator Akram Shalabi's group, and what stood out most wasn't the pacing itself, but the support that came with it.
“The pacers were giving little bits of advice throughout, reminding us to hydrate and stay relaxed. When you're aiming for a goal time, it's such a nice feeling to think, 'OK, I'll just trust this person and follow them.'
“You get to run in this little pack of people who are all working towards the same goal,” she explains. “A lot of your training is done on your own, so events can feel really special when you're all in it together.”
That sense of camaraderie is what made the experience so memorable for Amber.
“Everyone was encouraging each other, especially because it was a warm day. At the finish, people in our group were hugging each other and we had never met before. You get so much more than just achieving your time.”
Amber says pace groups can be especially valuable for runners attending on their own.
“At big events, it can feel like everyone else has come with friends or a running group.
“A pacer gives you someone to chat to at the Start Line and people to share the experience with. Even if you're someone who prefers to put your headphones in and focus on your own pace, it's nice having someone you can trust to follow.”
There will be pacers covering finish times from 1:30 to 3:50 at the Big Half. More details will be included in the Participant Guide, which will be available several weeks before Event Day.