Triathlon pacing plan: race strategy per distance and sport

Don’t mess up the pacing after all the hard training you’ve done. Here are concrete pacing targets for the swim, bike, and run across all triathlon distances: sprint, Olympic, 70.3, and full Ironman.

We’re about to look at race strategies per sport, but it’s important to acknowledge triathlon is a single race. Not a sum of three separate sports. Here are three important rules that apply to the whole race.

Rule 1: Pace by effort, not speed

You might have a specific finish time in mind. For example: finish a half Ironman in 6 hours. That requires racing at a certain speed. But don’t make the mistake of chasing a constant speed number.

Speed is a result, which depends on things like wind and hills. Your pacing on the other hand, should reflect what your body is actually doing. Think: power and heart rate.

In a case report of a female Ironman winner, they calculated the average speed, heart rate and power of each km. The conclusion was simple: heart rate (155 bpm) and power (199 W) stayed very stable from kilometer to kilometer (variation: 2.3% and 7% respectively). But speed (35.6 km/h) fluctuated a lot (> 20%) when you look at each kilometer’s average. Meaning some kilometers averaged well below 30 km/h while others pushed past 40 km/h.

Same story on the run: the average speed on each kilometer bounced around by 4.8%, while heart rate was held within 1.2%.

She clearly paced on effort, not speed. And you should too.

That does not mean effort should be perfectly constant though. On hilly bike courses, experienced triathletes push a little harder on the climbs and ease off on the descents. The reason is aerodynamics: extra watts on a descent get you almost nothing, while the same extra watts on a climb buy you real time.

The Ironman winner did exactly this: she pushed 10-15% harder on the climbs, compared to the flats.

But what metrics should you use to determine effort?

Lactate threshold heart rate

Most triathletes know their max heart rate, but for pacing, it’s better to calculate lactate threshold heart rate (LTHR), and use that instead. Note: your LTHR will differ per sport, so don’t use a single number.

Lactate threshold power

On the bike, power is often more useful than heart rate. Once you’ve calculated your lactate threshold power you can use it for pacing.

Lactate threshold pace

In both swimming and running, lactate threshold pace is still your go-to metric. Once you’ve determined the right running pace, make sure to monitor your grade (elevation) adjusted pace during the run, to ensure pacing on effort, not raw speed.

Rule 2: Pace evenly and protect the run

The most common way to wreck a triathlon is to start too fast. It feels great for twenty minutes and costs you for the hours to come.

The research is unusually consistent: across triathlon distances, athletes tend to drift into positive pacing, meaning they slow down as the race goes on. But that’s what people do, not what works.

The athletes who hold a steadier pace finish faster. In the professional field at Ironman Hawaii, the slower men paced increasingly positive on the run, fading as they went. The strongest held closer to even. The same pattern shows up across ultra-distances: faster athletes pace with less variation than slower ones.

Apparently it’s faster to push a little less during the entire triathlon, than to slow down at some point because you’ve overcooked it.

There’s one exception, and it’s the shortest race. In a sprint, a slightly faster start actually helps: the race is brief enough that a hard opening primes your oxygen uptake without blowing up the back end. The longer the race, the more this flips, until at full Ironman distance going out hard is the single most expensive mistake you can make.

In fact, the run is where good races are saved and bad ones fall apart. It’s the discipline that inherits every mistake you made earlier in the day.

The first half of a well-paced race should feel a little too easy. People will pass you early. You’ll pass most of them later.

The research backs the mechanism: reducing your swim intensity, rather than going all-out, leads to faster cycling and a faster overall triathlon time.

If you’re participating in a draft-legal race, this becomes even more important. Across Olympic-distance draft-legal races, run performance correlates with overall finish position, far stronger than the bike or the swim.

So underpacing the swim and bike isn’t a weakness, it’s accounting.

Rule 3: Pacing = Fueling

More and more triathletes have come to the conclusion that “Ironmans are an eating competition that happens while exercising”. That is because energy is a limiting factor in endurance. So the more energy you can consume (absorb), the more you can invest in the race.

But you have to pace your food intake too. It makes no sense to consume five gels in 15 minutes. It will simply 'sit' in your stomach. On the other hand: if you under-fuel, you’re leaving potential untapped.

Unfortunately, it’s impossible to consume as much energy as you burn, during the race. Luckily, you can train your gut to absorb more energy per hour.

Learn more about fueling:

• Full distance triathlon nutrition plan

• 70.3 Triathlon nutrition plan

• Sprint and Olympic triathlon nutrition plan

Let’s dive into the swim, bike and run pacing targets.

Pace, heart rate and power targets per sport, per distance

Now the practical part: actual ranges per sport, per distance.

A quick note before we dive in. The ranges below are starting points. Your ideal pacing depends on your training history, the course and your physiology. For instance: some triathletes might burn far more carbohydrates at 80% of threshold than others, which makes it a sustainable intensity for some and utopia for others.

Use race simulations in training, to find out whether the following targets work for you.

Triathlon swim pace plan

The most useful metric for swim pacing is Critical Swim Speed (CSS). Here’s how to perform a critical swim speed test and calculate your CSS.

If you know your 30 min swim distance or 1000m T-pace, you can use those to calculate CSS too. Use this article for calculations: Swim tests to estimate anaerobic threshold.

Say your CSS is 2:00/100m. CSS + 3-5s then equals 2:03 — 2:05 per 100m.

While this is useful in training, racing by feel (RPE) is usually more practical: no need to check your watch.

One practical tip for swimming: in a mass start, the first minute is chaos. Find clear water, then look for feet to draft. Drafting another swimmer reduces drag by 10-26%.

Short course (sprint, ¼, Olympic) swim pace recommendation

Short-course swims are 750m to 1500m and take roughly 10 to 35 minutes for most age-groupers.

These are the only races where a slightly harder swim opening can work, as we covered in Rule 2, but “harder opening” does not mean all-out.

Studies show that sprint triathletes produce the fastest overall triathlon time, when they swim at 80-90% of their max (750m) velocity. So if you can swim 750m in 10:00 mm:ss, 80% means you should aim for 750m in 12:30 mm:ss.

Highly trained athletes turned out to perform best at 80-85%, while moderately trained triathletes performed best at 90%.

If we extrapolate these findings to a ¼ Ironman or Olympic distance, it makes sense to maintain this range of 80-90% of your personal best on the swim distance you’re about to race.

In general it comes down to:

Target swim pace: 100% CSS (sprint) to CSS + 2s (Olympic)

RPE: 7.5 — 8.5

Half Ironman (70.3) swim pace recommendation

The 70.3 swim is 1900m and takes 30-45 minutes for most age-groupers. Long enough that going out too hard costs you on the bike. Short enough that you still want a respectable swim time.

The coaches consensus is to aim for:

Target swim pace: CSS + 3-5s

RPE: 6-7

Full Ironman swim pace recommendation

The full Ironman swim is 3.8km and takes 50 minutes to over 90 minutes. It’s the discipline where being relaxed and efficient pays off most, because there’s a lot of race left.

Ideally, you exit the water feeling like you barely raced. A good target to start experimenting with:

Target swim pace: CSS + 5-10s

RPE: 5-6

Triathlon bike pace plan: power and heart rate

The most useful metric for bike pacing is your Lactate Threshold Power (also known as FTP). Alongside, you can use your Lactate Threshold Heart Rate.

Say your FTP is 200W. 80% FTP then equals (200*0.8=) 160W.

Here’s how to perform a threshold power test and how to get to know your lactate threshold heart rate.

Sprint and Olympic bike power and heart rate plan

The sprint bike leg is 20km, the Olympic is 40km. In practice, this comes down to roughly 30 to 75 minutes on the bike.

The sprint allows you to go near threshold power, while the Olympic distance requires a slightly more conservative approach. Your heart rate will probably sit at or roughly 3-5 bpm below LTHR.

Target bike power: 85-95% FTP

Target bike heart rate: 90-100% LTHR

Half Ironman (70.3) bike power and heart rate plan

The 70.3 bike leg is 90km. Most age-groupers spend 2 to 3 hours on it.

Pacing during the bike leg is not only about intensity. You also need to focus on your 70.3 nutrition plan: getting your carbs in. This can be challenging, when heart rate will probably be only 5-8 bpm below LTHR.

Target bike power: 75-85% FTP

Target bike heart rate: 85-95% LTHR

Full Ironman bike power and heart rate plan

The full Ironman bike leg is 180km. With 4.5 to 7 hours in the saddle, there’s plenty of time to execute your full Ironman nutrition plan.

Remember that your goal is to arrive at T2 with legs that can run a full marathon. Try to keep your heart rate 8-10 bpm below LTHR.

Target bike power: 65-75% FTP

Target bike heart rate: 80-90% LTHR

Triathlon run race plan: pace and heart rate

Ready for the run? The first kilometre off the bike often feels wrong. Your legs are adjusting from cycling mechanics to running mechanics. Don’t panic. Settle into your pace by feel first, then check your watch.

Pacing is easiest done using your Lactate Threshold Pace. Here’s how to test and calculate your lactate threshold pace.

Say your threshold pace is 5:20/km (=320s/km). 80% threshold pace then equals (320s/0.8=400s=) 6:40/km. During the race, keep your grade (elevation) adjusted pace at 6:40/km.

Alongside, you can use your running specific lactate threshold heart rate.

Sprint and Olympic run pace

The sprint run is 5km, the Olympic is 10km. Most age-groupers run these in 20 to 55 minutes.

It’s clear that those runs need a different approach. In a sprint, you can push straight from the start (upper end of target), while the Olympic run needs a slightly more conservative approach (lower end of target):

Target run pace: 90-100% threshold pace

Target run heart rate: 90-100% LTHR

Half marathon pace and heart rate plan

The 70.3 half marathon run is 21.1km. Most age-groupers take 1:30 to 2:30. This is where 70.3 races are decided.

The safest approach is to start at the low end of your run target, and only push if you still feel strong past the halfway point. Heart rate will likely drift upwards regardless.

Target run pace: 85-90% threshold pace

Target run heart rate: 85-95% LTHR

Full marathon pace and heart rate plan

The full Ironman marathon run is, as you know, 42.2km. The time it takes differs a lot per triathlete, but you should roughly think 3:30 to 6 hours.

Similar to any long course run: start conservatively, at the lower end of your target. If that feels too conservative, that’s because it should.

Target run pace: 75-85% threshold pace

Target run heart rate: 80-90% LTHR

Literature

Pacing case report of a female Ironman winner

• Pryor, J Luke et al. “Pacing Strategy of a Full Ironman Overall Female Winner on a Course With Major Elevation Changes.” Journal of strength and conditioning research vol. 32,11 (2018): 3080-3087. doi:10.1519/JSC.0000000000002807

https://pubmed.ncbi.nlm.nih.gov/30161089/

Triathletes tend to drift into positive pacing.

• Wu SS, Peiffer JJ, Brisswalter J, Nosaka K, Abbiss CR. Factors influencing pacing in triathlon. Open Access J Sports Med. 2014 Sep 16;5:223-34. doi: 10.2147/OAJSM.S44392. PMID: 25258562; PMCID: PMC4172046.

https://pmc.ncbi.nlm.nih.gov/articles/PMC4172046/

The athletes who hold a steadier pace finish faster.

• Wu SS, Peiffer JJ, Brisswalter J, Nosaka K, Abbiss CR. Factors influencing pacing in triathlon. Open Access J Sports Med. 2014 Sep 16;5:223-34. doi: 10.2147/OAJSM.S44392. PMID: 25258562; PMCID: PMC4172046.

https://pmc.ncbi.nlm.nih.gov/articles/PMC10514275/

Faster triathletes pace with less variation.

• Stjepanovic, Mirko et al. “Changes in pacing variation with increasing race duration in ultra-triathlon races.” Scientific reports vol. 13,1 3692. 6 Mar. 2023, doi:10.1038/s41598-023-30932-1

https://pubmed.ncbi.nlm.nih.gov/36878948/

In a triathlon sprint, a slightly faster swim start helps.

• Wu SS, Peiffer JJ, Brisswalter J, Nosaka K, Abbiss CR. Factors influencing pacing in triathlon. Open Access J Sports Med. 2014 Sep 16;5:223-34. doi: 10.2147/OAJSM.S44392. PMID: 25258562; PMCID: PMC4172046.

https://pmc.ncbi.nlm.nih.gov/articles/PMC4172046/

Reducing your swim intensity, rather than going all-out, leads to faster cycling and a faster overall triathlon time.

• Wu SS, Peiffer JJ, Brisswalter J, Nosaka K, Abbiss CR. Factors influencing pacing in triathlon. Open Access J Sports Med. 2014 Sep 16;5:223-34. doi: 10.2147/OAJSM.S44392. PMID: 25258562; PMCID: PMC4172046.

https://pmc.ncbi.nlm.nih.gov/articles/PMC4172046/

Highly trained triathletes turned out to perform best when swimming at 80-85%, while moderately trained triathletes performed best at 90%.

• Peeling, P D et al. “Effect of swimming intensity on subsequent cycling and overall triathlon performance.” British journal of sports medicine vol. 39,12 (2005): 960-4; discussion 964. doi:10.1136/bjsm.2005.020370

https://pubmed.ncbi.nlm.nih.gov/16306507/