IMUK 70.3 Exmoor: 5 tips for nailing this tough middle distance triathlon

Racing IMUK 70.3 Exmoor? We have some tips from Matt Sanderson, co-founder of Triathlon Coaching UK, who will be racing it for a 12th time this year. Take it away Matt...


A race 220 rated as the 8th toughest middle-distance triathlon race in the world, IM70.3 UK, Exmoor will take place for the final time in its 12-year history on Sunday 25th June at Wimbleball Lake, close the picturesque town of Dulverton in West Somerset.


The very first IMUK 70.3 Exmoor race was staged back in 2006 and that particular race was the very first triathlon that Matt Sanderson, co-founder of Triathlon Coaching UK, took part in. Sleeping through his alarm clock that morning and arriving in transition just 20 minutes before the swim start, Matt had very little time to think about what lay ahead. Five hours later he was well aware of the 54 hills in 56 miles on the bike course and the seemingly endless hill climb to the farm on the run. After the race he didn’t go near his bike for a whole three months!

But Wimbleball, as it is now fondly known, gave Matt the triathlon bug and he has since completed the race every year since and will return this year for a 12th and final time. He is one of only two people who have completed the race every year since its launch so he’s ideally placed to offer his top 5 tips for getting through the hardest half Ironman on the planet.

1)    The water at Wimbleball Lake is incredibly clear – it’s one of my favourite places to swim – but has, in past years, been a little on the chilly side to say the least. If you’re not great with cold water, make sure you wear two swim caps or invest in a neoprene skullcap, it’ll make all the difference and you’ll be able to focus on your swimming rather than associated brain-freeze!

2)    Last year, race organisers changed the swim start to a self-seeded start meaning that you’ll line up with other swimmers who are of a similar pace to you. Complete a couple of race-pace 1900m open water swims in your training, record your time and make sure you’re ready in that particular time zone for the swim. Try and find someone’s feet as soon as you can and, if they’re going at your pace (and in the right direction!), stick with them to conserve valuable energy.

3)    Into T1 and it’s time for a real test of stamina and endurance to begin. However make sure you have checked what the weather is doing. I’ve ridden in wind, rain, snow, sleet, sun and cloud at Wimbleball and wearing the appropriate kit for the conditions is vital on the bike leg – otherwise you could be facing a very miserable and uncomfortable few hours on two wheels.

4)    My advice for the bike course is to save some energy for the second lap. Coming out of transition you are faced with your first climb – it will take around 15-20 minutes for most, and with fresh legs it’s easy to go out too hard. Don’t! Instead, use your gears and keep control of your heart rate. Try to ride at a controlled intensity on the flatter sections of the bike and ease off just before the climbs, which come on the second half of the lap. Make sure you take on your choice of food on the flatter sections (there aren’t many so don’t miss them!) and drink or have a gel on the climbs.

I would say: “spin up the hills” but at Wimbleball that simply isn’t an option. With three climbs reaching 20% gradient on each you have to work hard just to keep moving forward, as well as skilfully dodging fellow triathletes who may be zig-zagging or walking up. And another note of caution: there is a phenomenally fast descent at Bury Hill around 25km in. Underestimate this part of the course at your peril. The sharp left at the bottom has been the downfall of many participants over the years – the hay bales will only scrub off so much speed if you hit them!

5)    You’ve survived the bike, you’re now in T2 and just 13.1 miles stand between you and the famous red carpet. The run is always tough at Wimbleball. The three laps, with very little flat, take in a mixture of surfaces, from grass, molehills, gravel and tarmac to concrete, rough stony roads and muddy paths; pretty much everything that can bring on cramp and pain.

Focus on keeping good technique throughout and pace yourself appropriately using your chosen brand of sports watch. There is a lot of support on the run course but this is a psychologically and physically challenging course. Concentrate on putting one foot in front of the other and try to make the most of the stunning surroundings. When you cross the finish line, the pain will all be worth it and the bragging rights of completing the world’s toughest 70.3 will be all yours.

So, to sum up: Enjoy the unique challenge that this race presents and forget all about PBs. Take in the amazing scenery wherever you look, the beautiful water, embrace the hills on the bike course and whatever happens – do not walk up that bas*a#d hill on the run.

 Matt Sanderson is a BTF Level 3 coach and has qualified for the IM 70.3 World Championships three times. Find out more about him at

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