Duathlon: 36 preparation, pacing and racing tips

Planning to race duathlon? Read on for our best tips on how to prepare, how to pace and how to perform on race day.

Credit: The Secret Studio

Planning to race some duathlon? Duathlon is fraught with performance pitfalls, from opening run pacing mistakes to double jelly-leg syndrome and clothing catastrophes, which is why we’ve produced your ultimate guide to smashing duathlon, featuring the key sessions, race-day advice, and much more.


While it may lack the exposure of its slightly-elder sibling, duathlon is an enthralling challenge in its own right; a pure battle with the elements that’ll test your pacing abilities, stamina and speed to their outer limits. And the often bitingly-cold conditions open up another dimension to the race, one that many believe is a tougher all-round experience than tri.

The format finds triathlon’s swim leg swapped for an opening run, which over the standard duathlon-distance of 10km run/40km bike/5km run doubles the amount of running compared to an Olympic-distance triathlon. While that may sound like triathlon without the scary bit at the start, a duathlon is fraught with performance pitfalls, from opening run pacing mistakes to double jelly-leg syndrome and clothing catastrophes.

That’s why we’ve produced your ultimate guide to smashing duathlon, featuring the key sessions, race-day advice, and much more. And, as an added bonus, including duathlon in your racing programme from autumn through to spring is also a surefire way to boost your multisport conditioning, improve endurance and strengthen your
race performance come the next triathlon season. Now, what are you waiting for?!

3 duathlon training sessions

The key sets to have you ready to face the multiple challenges of racing a run/bike/run event

1. Fast-pace efforts

Benefits Prepare the body to run hard when feeling fresh; get used to relaxing when feeling uncomfortable; and simulate race situations – the chance to practise changing pace when already going hard.

When: Include six weeks out from the race. Reduce to two sets a week out from race.

Kit needed Running gear, gels and energy drink.

Warm-up: 20min easy jog, drills & strides

Main session: 4 x [2mins @ 3km pace; 30secs fast; 2mins recovery]

Cool-down: 15mins jog & stretch

2. High-intensity sprints

Benefits: Get you race ready; develop max power; and make you feel sharp on race day.

When: Six weeks out from the race. As the race gets closer, reduce number of reps and increase rest.

Kit needed: Bike gear and energy drink plus gels.

Warm-up: 20mins easy bike

Main session: 15 x 30secs max efforts. 2mins rest

Cool-down: 20mins cool-down

3. Bike/run brick

Benefits: Mental and physical conditioning.

When: Six weeks out from racing. Aim to simulate racing conditions, get used to holding your race pace and managing fatigue while maintaining form and pace. Reduce to one set a week out from the race as this’ll keep your body race sharp.

Kit needed: Race-day kit. Experiment with base layers and compression clothing. Have a planned nutrition strategy before the session. Stick with this each week and for the race.

Warm-up: 10mins steady bike, 5min easy run & mobility and drills

Main session: 2x [10mins bike @ race watts, 5min run @ 10km pace]. No rest between sets

Cool-down: 10mins cool-down jog & stretch

5 tips on how to beat the cold

Duathlon race day can involve rain, snow, sleet and sunshine. So how do you overcome the elements?

4. ‘There’s no such thing as bad weather, only bad clothes’, so the popular Norwegian saying goes. And as frustrating as it is to accept, not fully planning for the weather can severely affect your performance.

5. A thorough warm-up is a great way to enable the body to perform at its best. The aim is to elevate the heart rate, increase blood flow to the muscles and raise your body temperature. Racing in compression gear or arm sleeves, as well as your tri-suit, will allow the body to carry forward the physiological effects of the warm-up into the first run.

6. Coming in sweaty after the first run can place you in a precarious position going onto the bike. It’s normal to cool down when you start riding, so keeping dry and comfortable is ideal when trying to hold power. Your extremities will feel the cold the quickest. So having gloves and a spare pair of socks if it’s wet, alongside a waterproof/windbreaker jacket and thermal toe caps on your cycling shoes, will help keep you cosy during the ride. To prevent your drink from freezing, a thermal bottle is another great addition.

7. Being in the cold for some time can cause your body temperature to drop, which can lead to shivering. This is due to your body having a higher metabolic rate in these conditions, and may cause unnecessary loss of calories as you use more carbs than fats in the cold. So take an extra couple of gels and bars than you would normally.

8. As in hot conditions, it’s important to rehydrate post-race. In the cold, you still lose water through breathing and sweating, but low temperatures increase urine output and diminish your thirst. Start with a warm drink to raise body temperature.

9 tips for pacing the duathlon

Go out too fast in a duathlon and you’ll pay for it later. But how do you master the first run leg, balance the bike and race for glory on the final run?

9. If you’re new to duathlon, you might not have much experience of running fresh, so you won’t know what your race pace actually is. And it can be all too easy to start off too fast, hit the front, feel great, and then after few kilometres get hit by a wave of fatigue and end up clawing your way to the finish line. So it’s important to pace the first run so that you conserve enough energy to maintain power on the bike and hold your race pace on the second run.

10. To successfully pace the first run, aim to keep within your aerobic zone. If you’re unsure, take your 10km PB and add 8-10mins to the time. If you don’t have a 10km time, run the first 5km at a controlled pace, where breathing is sustainable and then aim to hold the same pace for the second. Any slower could lead to feeling sluggish and a loss of race sharpness.

11. As you approach transition, maintain a steady heart rate and breathing. If you’ve paced it right, you won’t need to slow down and will be able to effortlessly jump onto the bike to begin the next discipline.

12. Bike and running movements predominately work the same muscle groups. But the mechanics of these two movements and the muscles involved are used in different ways. During a duathlon, you have to transition twice between these two disciplines so the ‘jelly legs’ sensation that’s common in a triathlon is potentially doubled during a duathlon.

13. Similar to tri, make sure you leave your bike in a light gear in transition. If you go into a heavy gear too early it can further fatigue your legs and compromise the final run. When you begin cycling, aim to hold a high cadence for a couple of minutes. This’ll aid recovery from the previous run, help your muscles adapt to the action and help get your bike legs back quicker. Once settled, shift up a few gears, relax into your position and begin applying the power.

14. During the bike leg, there’s a good chance that your body, especially the legs, will be feeling much more fatigued than in a tri. Your body may be in greater calorie deficit after the first run than it’s used to after a swim. So it’s important to replace these lost calories immediately and reboost your energy. That’s why it’s not uncommon to have a different nutrition plan for a duathlon compared to a tri. Practising different nutrition strategies during duathlon brick sessions will ensure that the muscles are quickly replenished and power maintained.

15. Transitioning onto the final run and you’re back in familiar triathlon territory. But this time, the wobbly bike legs are accompanied by the feeling of an elephant strapped to your back! This is what makes duathlon so challenging and why it’s common for the final run to feel like your legs are full of cement. Just remember that is a completely natural feeling to experience.

16. As you begin to approach transition, like you did when you got on the bike, move into a light gear and increase the cadence. This’ll help the legs recover from the heavier gear and accelerate the transition to your running legs.

17. It’s important that you don’t go full gas as you may run the risk of cramping. Start steady and aim to find your rhythm quickly. Keep control of your breathing and try and maintain a high cadence as this’ll make your running feel more efficient (long strides will only add unnecessary fatigue to an already exhausted pair of legs). As you approach the finishing chute – having paced the race to perfection – it’ll be time to unleash the last drops of energy: crossing the finish line, arms in the air, you are now a duathlete!

19 tips for going off-road

18. The UK hosts a number of off-road duathlons, and the tricky conditions only add an extra challenge to these events. Getting ready for these races isn’t quite as easy as swapping the road bike for a mountain bike and the uncertainty around each corner is what gives these races such a buzz. To conquer them successfully, you must be prepared, adaptable and conditioned.

19. It’s important that you spend a good part of your training running on trails, including ascents and descents, as uneven terrains will fatigue your body quicker if you’re not used to them. Negotiating these variables are a skill in themselves and are a great way to get an advantage over the competition.

20. Unlike its road cousin, the first run of an off-road duathlon is on uneven surfaces. Footwear with a substantial amount of grip is essential to staying balanced, for example when leapfrogging over uprooted trees and stepping through boggy patches.

21. Hill climbing is notoriously hard and easy to get wrong. But get it right and you’ll overtake your competitors with ease. The key is much smaller steps – long strides are hard to maintain. Focus on raising your knees higher, shifting your weight to the balls of your feet and moving your legs from your hips.

22. After completing the first run, it’s now time for the mountain bike: fun and exciting, yet nerve-wrenchingly terrifying all at once! It’s a different experience to being on your road bike as there’s less focus on aerodynamics and more attention on stability and balance. If you’re new to MTBs, opt for open pedals as these allow you to put your foot down and provide more confidence to your ride. Also, look into the type of tyre options and pick the ones with the best grip.

23. During the bike section, you may encounter extreme terrain, steep inclines and declines. All at the same time on some courses! So it’s essential to practise extensively on your mountain bike in training before racing. Knowing where to place your centre of gravity when going up and downhill will prevent excess energy loss.

24. Mountain bike handling is about staying relaxed and flexible. As you ride, look further down the trail and not on the front wheel. Focus on how your weight is distributed on the bike. This’ll help when handling different types of obstacles and preventing any unexpected trips over the handlebars!

25. When riding descents, stand up on the pedals and keep your arms and legs flexed. Keep your body low, elbows and knees bent. Move your hips back, so they’re slightly behind the saddle. In this position, your body can absorb any forward forces using your legs, instead of your arms and handlebars.

26. Keep your weight on the back wheel to maintain traction when ascending. When steering, you need to position your weight on the front. The compromise is to stay seated and move your body forward, sitting on the nose of the saddle. Drop into a light gear and up you go.

27. The aim is to exit the corner with as much speed as possible. Braking while turning leaves less grip for the tyres to get round the bend and you can lose speed and control. Lean the bike underneath you, keep your weight over the tyres, knees flexed and off you go.

28. Mountain bikes have a greater range of gears compared to their road counterparts. This allows you to fine-tune your cadence to overcome all sorts of obstacles. Avoid using extreme gear ratios as the chain may be either too taut or slack to work well and could cause a mechanical.

29. When riding off road, there’s no optimum cadence. The constant changes on the trails means we must adapt to the terrain to save energy and not lose grip. Train yourself to be efficient in a wide range of cadences as this’ll be a big advantage on race day.

30. Onto the second run and the trails challenge you to constantly adapt your stride pattern and length. Relaxing while doing this is essential to running successfully off road. So, to navigate effortlessly off road, you must constantly shorten, lengthen, strategically position your feet and co-ordinate your arm action to maintain efficiency.

31. Every trail is different. Even if you religiously practise on the same track, it’s not uncommon for obstacles to have moved or have been added. When running off road, it’s always important to stay alert, look further ahead down the trail and to constantly plan the next move.

32. Planting your foot and powering off will ensure you maintain your running momentum through the trails. Having excellent grippy trainers will be essential for this.

33. It’s easy to lose control when running downhill. Your stride can become too long as you naturally speed up due to the pull of gravity. Three technical tips to focus on are: 1) Feet under your body. 2) Maintain an upright posture. 3) Raise your feet from the ground as little as possible.

34. Arm movement is essential to your overall rhythm, so adapting your arm movements to the changing terrain is crucial to running efficiently. Running uphill, your arms should swing in short, sharp movements. Going downhill, use your arms to control momentum.

35. Bullet-proofing your ankles is key to pain-free trail running. Add balancing exercises on unstable surfaces to your S&C programme (e.g. on the BOSU balance trainer). Also, include core exercises to maintain run form on uneven surfaces.


36. By the end of the final run, you’ll be covered in mud. Muster all the strength you have to maintain pace and crossing the finish line will feel just as exhilarating as being on the trails.