Dirty Duathlons

Nik Cook gives you the low down on off-road duathlons and why they should be part of your autumn and winter racing schedule.  This article was first published on 28th September 2016 and is a feature piece from Totally Active.

Who are they for?

Anyone from experienced triathletes looking for a competitive outlet through the winter to complete novices after their first multi-sport taster. Most people have a mountain bike lurking in the garage and, with no traffic to worry about, they’re ideal if you’re a little nervous on the bike.

How tough are they?

They vary depending on the terrain so, if you’re a novice, look for events in flatter areas. However, in general, the distances covered are fairly short. At the sharp end of the field, the racing is hard but, if finishing and having fun are your main goals, just pace yourself and you’ll be fine.

How technical is the biking?

Again it depends on the event but most will stick to wider fire-roads with occasional more technical singletrack sections but nothing usually above red grade. Events based at trail centres may well use one of the graded loops so, if you’re worried, maybe head over and ride it first under non-race conditions.

Will it benefit my regular triathlon?

Yes, it’s no coincidence that many top triathletes race both on and off-road duathlons through the off-season. Mountain biking is a great way to develop strength, power and it’ll certainly improve your bike handling skills. Trail running is also brilliant for strength and the varying terrain will challenge your core stability and balance.

Where and when do they happen?

Most make use of mountain bike trail centres, Forestry Commission land or even military training areas. The off-road duathlon season runs right through the winter from October to March including race series in the South, Midlands and North or the country.


Key Kit

  1. Bike: Any well maintained mountain bike will be fine for giving an off-road duathlon a go. Most of the top racers will be on cross country orientated 29’ers, taking advantage of the faster rolling bigger wheels.
  1. Running shoes: Aggressive trail or fell shoes that grip no matter what the surface and that shed water quickly. Don’t forget to put in some elasticated laces to speed up your transitions.
  1. Shorts: You need shorts that are comfortable to run in but also give you some padding on the bike.
  1. Arm-warmers: A versatile essential for those cold starts which can be whipped off and stowed once you’re up to racing heat
  1. Transition bag/box: An organised transition area, with your kit neatly laid out, can save significant time. A box is a must have.

Race day story: Robin Hood Duathlon 2012

If at first you don’t succeed… Nik finally hits the mark at the Robin Hood Duathlon.


I had unfinished business with this 5 km/16 km/3.6 km off-road duathlon. In 2010 I was misdirected by a marshall while leading on the bike and the results were voided. In 2011, again while leading on the bike, I sheared off a pedal and recorded a DNF. Would 2012 be my year? I had good endurance left over from an age-group World Championships win at Powerman Zofingen but whether I could get my legs turning over quickly on the short runs remained to be seen.

Staying at one of the forest cabins onsite at Sherwood Pines, I’d got in a recce ride of the bike loop the day before and, despite an early 0900 start time, my alarm went off at the relatively civilised time of 0700. After my usual gallon of coffee and a bagel, I loaded up my transition bag and rode over to the start. The morning was beautiful, cold, crisp and the autumn colours in the forest were stunning. I racked my bike and trotted off into the woods for a warm-up. My legs felt rubbish but that’s always the case on race day. I finished up with a few strides and got back to the start just in time for the briefing.

From the gun, I was near the front of the field and, approaching the 1 kilometre mark at the start of an uphill drag, found myself in third place. Fifty meters or so ahead the first two were battling for the lead but I wasn’t losing any distance, was confident of my bike and settled into a rhythm. I hit T1 in 17:32, just over half a minute behind the leader. I slipped off my running shoes, stepped into my bike shoes but my right foot wouldn’t go in. I’d left my bloody tyre pressure gauge in my shoe but, after some hopping about, shoe banging and a warning from the referee for swearing, I was finally on my bike.

My plan was to hammer the first lap as, on the second, you start passing back markers and can get held up. Within a couple of kilometres I caught sight of the leaders, rode up to their wheels and made the pass on a climb. I buried myself to ensure they didn’t jump onto my wheel and quickly opened a gap. I went into time trial mode, piling on the power, sprinting out of corners and trying to stay smooth through any technical sections. I rode hard on lap two, putting in sprints as I overtook slower racers and, although their erratic riding was frustrating, I knew my chasers would be having the same problems. The stop-go efforts took their toll on my legs but, as I came into T2 with a split of 41:31, I was confident I’d opened up a decent lead.

As I trotted in with my bike, in I heard the commentator over the tannoy “Here’s our leader Nik Cook, Long Course Duathlon age-group World Champion, watch how a transition should be done!” No pressure then. I had a moments wobble about which rack row I was in but managed a fairly slick 36-second effort and headed out for the final run.

After I’ve run about 200 metres, I saw the second and third placed racers coming into T2 and knew that I’ve got at least 90 seconds in hand. I pushed hard on jelly legs for the first kilometre to get out of sight and then, checking back on a long straight and seeing no-one, eased back into cruise mode. It was great to be able to enjoy a pressure free run-in and, even better, as I crossed the line with a second run of 12:28, to put my Robin Hood demons to bed.


Top Training Session

Off-road duathlons are normally fairly fast and furious. A multiple brick session, where you swap continuously from running to biking and back again, is a brilliant way to get up to race pace, get used to the jelly legs off the bike sensation and to practice your transition skills.

A mountain bike trail centre is the ideal location for this session as you can use your car as a secure base for transition.

Find a run lap that takes you approximately 5 minutes to cover and a bike loop that takes about 10 minutes. Make sure both loops have some hills and technical features.

Warm-up with two gentle laps of your run loop, slowly increasing the intensity.

On your third lap, increase the pace to an effort that feels similar to your 5 kilometre race pace.

Transition onto your bike and ride your 10-minute loop, again your looking for a race pace effort.

Back to the run and keep alternating for two to four complete cycles but always finish with a run. Aim for consistent splits and, on the runs, to settle into your race pace as quickly as possible out of transition.

Cool down with an easy 10-minute spin on your bike.


Races to do

Midland Off Road Series

17th October, 7th November and 21st November

With races at Clumber Park, the National Water Sports Centre in Nottingham and at Sherwood Pines, where you can see if you can beat Nik’s splits, it’s a varied and challeng-ing series.

High Terrain Events Off-Road Duathlon Series

15th November, 6th December, 13th March, 24th April

Taking place at Kielder and in the Lake District you can be sure of some stunning scenery and challenging trails. The bike leg at Whinlatter is one of the best there is.

Human Race Off-Road Series

21st November, 5th December, 5th March

Three events held at locations across the south east including an Army Testing Ground. At the Mudman series finale, you’ll tackle a 50 foot water section.


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This article is a feature piece from Totally Active, a completely interactive online magazine written by active people for active people. Totally Active are on a mission to push endurance to its limits, to help readers achieve their potential, whatever the sport or activity. Totally Active have brought some of the world’s foremost endurance, performance, nutrition and fitness experts together in a publication which informs and inspires readers to go to the edge, to break boundaries, and to succeed. Read more articles like this at Totally Active today.