Pacing Is One Decision, Made Early.

Every athlete who has ever walked in a triathlon run leg believes the run was the problem.

It almost never is. By the time you are walking, the decision that put you there was made ninety minutes earlier, on a bike, feeling good, going slightly too hard in a way that felt entirely sustainable at the time.

You do not pace three disciplines. You pace one race, and you commit to it before you are able to feel whether you were right.

The Swim Sets the Tone

The swim is the shortest leg and it is where most people spend the most nervous energy.

A hard first two hundred metres in cold water with people around you produces a heart rate spike that takes several minutes to come down, and an oxygen debt you carry onto the bike. You gained maybe fifteen seconds. You will spend three or four minutes of the bike paying for it while you settle.

So: start controlled, deliberately. The first two hundred metres should feel restrained. Let the people who go off hard go, because a good proportion of them will come back to you by halfway.

The purpose of the swim in a triathlon is to arrive at the bike in good condition. That is the entire brief.

The Bike Writes the Run

This is the whole thing. If you take one idea from this, take this one.

Your run split is not determined by your run fitness. It is determined by how much you have left when you start running, and that is entirely a function of how you rode.

The numbers most athletes should ride at, as a fraction of FTP, are lower than they expect. Roughly seventy five to eighty five percent for a sprint or Olympic, around seventy to seventy eight for a 70.3, and around sixty five to seventy five for full distance. Those figures feel too easy in the first half hour. They are supposed to.

The other number that matters is variability. Riding a steady effort is meaningfully cheaper than riding the same average power in surges. Every hard effort over a rise costs you more than the equivalent easing on the descent gives back, and a bike leg full of surges empties you in a way the average power does not show.

So on climbs, let the power rise a little but not much. Over the top, keep pedalling rather than freewheeling. And when somebody passes you, let them go. The single most common way athletes lose a race is by racing the person next to them instead of the plan.

The Run Is Where You Find Out

The first two kilometres should feel too easy. If they feel comfortable and correct, you are going too fast, because your perception is unreliable at that moment.

Coming out of T2 you have adrenaline, fresh legs relative to the bike position, and a crowd. Everything is telling you to run. What you have is the least reliable pacing instinct you will have all day.

I ask athletes to run the first two kilometres at what feels like an effort of five out of ten, deliberately holding back, and to assess at kilometre three. If you get to three and feel strong, you can build. Almost nobody who does that regrets it. Almost everybody who does the opposite does.

A negative split run in a triathlon is not a nice bonus. It is the signature of a correctly paced race.

What to Do When It Goes Wrong

Sometimes it does. The heat is worse than forecast, the stomach turns, the legs are not there.

Reset rather than abandon. Slow to a pace you can hold, take on fluid and something simple, and give it fifteen minutes before making any judgement about the day. A surprising proportion of very bad patches in a race are transient, and the athletes who walk permanently are usually the ones who made a decision about the whole race during the worst four minutes of it.

The Bottom Line

Swim controlled to arrive in good shape. Ride steady, lower than feels right, and let people go. Run the first two kilometres too easy and decide at three.

You will not be able to tell whether you paced it correctly until the last half hour, which is why it has to be a decision rather than a feeling.