From 25 Dec 2024 to 5 Mar 2025

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Our One Slam virtual event is back for the fifth time in 2025, once again encompassing Christmas week to give everyone a running head start into the new year.

The event takes place over a 10 week/ 70 day period: 25th December 2024 - 5th March 2025. Runners have a choice of distances that they can aim to complete within that time. The option to step up to the next level, or down if it becomes too much - is there at any time, just keep going! The event is for everybody, anywhere in the world. The targets are as follows:

50 Miles (5 miles per week)
100 Miles (10 miles per week)
200 Miles (20 miles per week/ The equivalent of the 50 Mile Grand Slam)
300 Miles (30 miles per week)
400 Miles (40 miles per week/ The equivalent of our 100 Mile Grand Slam)
500 Miles (50 miles per week)
600 Miles (60 miles per week/ The equivalent of our Double Slam)
1000 Miles (100 miles per week)

Part of the One Slam focus is helping our Centurion runners start the year on the front foot, but not just by encouraging consistent training, but also good opportunities to learn as well. As part of your One Slam entry you will have access to fortnightly webinars from our coaching team, on subjects such as training, nutrition, kit, racing and more. As well as open time for questions after each. These were popular in 2023 and 2024 and will return in 2025. 

We will also be including a One Up Week - with awards - which as an entrant to One Slam you will be able to enter for free. One Up will take place 17th-23rd February 2025. See below for further details.

Here is a link to the 2022 Results/ Report2023 Results/ Report and 2024 Results/ Report to get a picture of what sort of targets our runners are aiming for.

General Info

What is It 

The challenges are once again based around our traditional Grand Slams - spanning a time frame of 70 Days. Runners will have between December 25th 2024 and March 5th 2025 to take on their chosen distance. Kids can enter and compete on bike or scooter if they wish.

You can also register for the canicross event - Simply select 'yes' during registration to 'running with a dog?' and you will appear in your age group but also the canicross category (medals are not provided for our canine friends but you can give them your one!).

All you have to do is run whenever and wherever you like, then submit your distance to the database. You can do this automatically, by syncing your entry with strava or by just manually entering how far you ran, each time you do so. The system will then calculate your total distance and update both the results table and your position on our virtual map. It will add together your cumulative run distance only. 

The results for each event will show in order of cumulative distance only. Remember this is not a race, the primary objective is to complete the challenge you set for yourself and to engage with your friends, family and the Centurion Community by sharing your journey. 

Beyond the results/ leaderboard this is about community engagement. We want you to share the journey to your own finish line via any and all social media channels. You can tag us on facebook, twitter or instagram under the hashtag #centurioncommunity. Photos are strongly encouraged! We will share what we can and award spot prizes to the best uploads and engagements over the course of the event.

We also want this to give you all the best possible start to your 2025 season, to learn about your training and improve your running in the process. To compliment this, we will be holding fornightly coaching webinars on Zoom - open to all entrants. These will be led by Robbie Britton our Head of Endurance at Centurion and each one will also feature at least one other member of our coaching team. The first one will take place on just prior to the event and will be open to everyone including non-Slam runners. After that, links to the webinars will only be shared with entrants to the event. Topics covered will be different to 2024, but as an idea as to what they will cover the previous editions were as follows:

  • One Slam Success: Reaching your goals with lessons from last year.
  • Training Wisdom: Crafting your own ultra-training plan.
  • Mental Grit: Sports Psychology skills for ultra-marathon resilience. 
  • No such thing as bad weather: Choosing the right kit for your adventures
  • Fuelling Excellence: Nutrition strategies for ultra-runners in training and racing.
  • Race-Day Mastery: Strategies for ultra success on the big day.

All of the sessions will be conducted via zoom. Links and meeting details will be shared in the pre-race mail outs and in the lead up to each one.

We will also be holding a ONE UP week from February 17th - February 23rd. This is optional, free with your One Slam entry and comes with its own set of awards that will be sent out to all finishers. This is a repeat of the event we held in July 2020 and the idea is to accumulate as much vertical as you can during the week with totals ranging from Box Hill at 735ft, up to Olympus Mons at 69,648ft! Further details on entering One Up for free, will be shared with all One Slam entrants nearer the time.

What You Get 

  • Personal Bib Number - downloadable at the start of race week by clicking on your race number on the Entrants page here
  • Live updates to your progress throughout the event via the Leaderboard
  • The option to compete in the One Up Virtual Week at No extra cost - with it's own leaderboard and awards (medals) sent out to you on completetion of the One Up week.
  • One Slam Medal sent to you in the post once you complete your event - this will be a large metal medal (100mm wide) pictured below, with the event logo. The ribbon will be a blue woven ribbon as shown, with your completed race distance and our logo.
  • Fortnightly webinars from our coaching team, headed by Robbie Britton and our team of coaches, on subjects such as training, nutrition, kit, racing and more. As well as open time for questions after each.
  • If you complete the 1000 mile distance on foot, you will receive a huge buckle for your efforts. 150mm wide.
  • **You can opt out of receiving the medal or buckle during the registration process, in favour of planting a tree with trees not tees
  • Spot prizes for best posts/ photos/ interactions via social media/ email and the hashtag #centurioncommunity 
  • 10% of all entry fees will go to our charity partner MIND (Charity no. 219830). This is something we have always done for our virtual events.



How to Register 

You can register by clicking on the button linked at the top of this page. Registrations are open until the final minutes of the event, so you can join in at any time and count any mileage you have already accumulated after the start of the event.

During registration you are able to register for just you, or an extended group of family or friends as you wish.

The event is open to everybody no matter your age or location. We hope to see many international runners taking part. 

You can also register for the canicross event - Simply select 'yes' during registration to 'running with a dog?' and you will appear in your age group but also the canicross category.

When you sign up you will need to include a shipping address. We will then post out your medal or buckle to you when the event finishes

Entry Fee

Entry fees are the same as for all previous editions.

  • £30 Early Bird Fee for Adults until 1st September. £40 thereafter.
  • £15 for Under 18s at all times