How to plan a triathlon season (without a coaching textbook)

A triathlon season plan is built backward. Pick the one race that matters most, put it on the calendar, count the weeks between now and then, and fill them in starting from the race end: taper first, then the race-specific build, then the general base work that has to happen before any of the specific work pays off. Every other race, every recovery week, and the off-season arrange themselves around that spine.

That is periodization. The textbook version runs to several hundred pages and uses words like mesocycle. The working version fits on one page, and the rest of this article is that page.

Start with one race, not twelve

The first decision is which race you actually care about, and the honest answer is one, occasionally two. Not because you should race less — because peaking has a real cost. You spend two or three weeks shedding fatigue to arrive sharp, you race, and then you need real recovery afterward. Try that four times in a season and you spend more of the year tapering and recovering than training.

So classify everything on your calendar. It is the oldest trick in the coaching book and the highest-value thirty minutes of planning you will do:

The labels are commitments, not aspirations. If you find yourself taking five easy days before a race you called a C-race, it was never a C-race, and you have quietly given away a week of your build. The point of writing the letter next to the race in January is that it settles the argument you would otherwise have with yourself in June.

If you pick two A-races, put real distance between them. Eight to twelve weeks is enough to recover, rebuild, and re-sharpen. Four weeks is not — you will show up to the second one flat, having spent the gap trying to be both recovered and fit.

The phases, by what they are actually for

Phase names are the part of periodization everyone remembers and the least useful part. What matters is what each stretch of the season is trying to change about you.

Base — become the kind of athlete who can absorb training. The goal is not to be fast. It is to build a body that can take the work you will throw at it later without getting hurt. That means durable aerobic volume, mostly easy, at a level you can repeat week after week. It means swim technique, the one place in triathlon where a stroke change is worth more than any amount of fitness. And it means a strength foundation — two short gym sessions a week, which is also your best available injury insurance for the run.

The mistake in base is treating it as a holding pattern. Base is where the largest, slowest adaptations happen, and skipping it does not show up until eight weeks later, when the hard sessions stop landing.

Build — get specific about the race you signed up for. Everything in build should look more like race day than the thing it replaced: steady bike work at the effort you will actually hold, running off the bike rather than fresh, open-water swimming if that is where you will race, nutrition rehearsed at race intensity rather than sipped on an easy spin. Intensity goes up, and total volume usually flattens or drops slightly to pay for it.

Peak and taper — shed fatigue without losing sharpness. The taper is not a rest week. Volume drops hard, but the short, sharp, race-pace work stays in, because that is what stops you arriving fresh and flat. Two or three weeks of reduced load will not make you fitter. It converts fitness you already have into a performance you can actually deliver.

Transition — stop, on purpose. One to three weeks of no structure after your A-race. Swim because you want to, ride if the weather is good, or do nothing at all. This is not a euphemism for reduced training. It is the phase that lets you start next season wanting to train, which over a decade of racing matters more than any block you might have squeezed in instead.

How long each phase should be

Honest ranges, with the caveat that they overlap and that your calendar rarely offers you the ideal number:

• Base: 8–16 weeks. Toward the long end if you are newer, coming back from injury, or racing long. Toward the short end if you finished last season fit and are carrying that fitness forward.
• Build: 6–10 weeks. Under six and the race-specific work never accumulates. Past ten, most athletes are just accumulating fatigue at a level they cannot keep clearing.
• Taper: 1–3 weeks. Roughly one week for a sprint, one to two for Olympic, about two for a 70.3, two to three for a full Ironman. Longer races need longer, because the fatigue you are clearing was built by bigger sessions.
• Transition: 1–3 weeks after your A-race, and the whole thing again as an off-season at the end of the year.

Now the part the textbooks bury: the boundaries are soft. There is no Sunday where base ends and build begins. A good season slides gradually from general to specific — a little more race-pace work each block, a little less undirected volume — and if you ask an athlete mid-season which phase they are in, the useful answer is often "somewhere between two of them."

Worth being blunt about the evidence, too. Traditional periodization, reverse periodization, block periodization: the comparative research in trained endurance athletes is thinner and noisier than the confident diagrams suggest. What holds up is much simpler. Load should progress. Recovery should be planned. Work should get more like your race as the race approaches. Every named scheme is a different arrangement of those three, and the arrangement matters far less than actually doing them.

A 24-week 70.3 season, as a skeleton

This is a shape, not a prescription. Twenty-four weeks from a standing start to a middle-distance A-race, assuming you can train roughly 8–12 hours a week.

Recovery weeks are already inside that table: weeks 4, 8, 12, 16 and 20 run at roughly 60% of the surrounding volume. That is a three-weeks-on, one-week-off rhythm, which suits most age-group athletes. If you are over about 45, sleeping badly, or in a demanding stretch at work, two-on one-off is not a lesser plan — it is the right plan for that person, and it produces more usable training than a 3:1 cycle you keep failing to complete.

Recovery weeks go in the calendar first

Write the recovery weeks into the plan before you write anything else into it. A recovery week you scheduled in January is training. A recovery week you take in May because your legs stopped working is damage control.

A real recovery week cuts volume by roughly 40–50% and keeps a little intensity — a few short, sharp efforts so you do not go stale. If you track training load, your fitness number should visibly fall, on the order of 3–8 points of CTL. If it holds flat, that was a slightly quieter build week wearing a recovery week's name, and you did not bank the adaptation you were trying to buy.

What the load arc should look like

Zoom out and a well-shaped season has a recognizable profile. Load climbs in a sawtooth: three weeks up, one week down, each cycle's peak a little higher than the last. The climb is gradual — a few points of CTL a week is sustainable for most athletes, and steeper sustained ramps are where injury and illness cluster. Total load peaks two to three weeks before your A-race, then falls through the taper while freshness climbs to meet race day.

Two honest notes on that arc. The peak number is not the goal; the race is, and athletes who chase a round CTL figure in the last month before an A-race pay for it with a taper that never fully clears. And the arc has to fit the hours you actually have across the whole season, not the hours you had in your best week. Building a plan around 12 hours when you realistically have 8 does not get you a 12-hour athlete. It gets you a plan you fail every week, which is worse in every measurable way than an honest 8-hour plan.

A season plan is a forecast, not a contract

Here is the part that separates plans that survive from plans that get abandoned in week eleven.

You will not complete your season plan as written. Almost nobody does. Somewhere in those 24 weeks there is a chest infection, a work deadline that eats two weeks of mornings, a fall on a wet corner, a child who stops sleeping. That is not a discipline problem. It is the base rate of being an adult with a life, and any plan that assumes otherwise was built for someone else.

What separates athletes is not whether the plan breaks. It is what they do in the week after it breaks. There are two classic wrong answers.

The heroic resume. You lose ten days, come back, and pick up at week fifteen because that is what the paper says. But the plan's week fifteen was written for a body that had just completed week fourteen, and yours did not. The session lands too hard, you dig further into a hole you are already in, and the second setback arrives faster than the first.

The abandonment. The plan is broken, so the plan is dead, and you spend the next month training by feel with no direction at all — which in practice means the sessions you enjoy, at the intensity you feel like, none of it pointed at anything.

The correct answer is neither. Re-plan from where you are. The durable content of a season plan is not the list of sessions; it is the race date and the direction of travel. Both of those survive a disruption intact. What has to be recalculated is everything in between: given the fitness you actually have today and the weeks that are actually left, what is the best use of them?

That usually means a shorter, more specific build, because specificity is what wins races and general aerobic volume is the part you can most afford to lose. It sometimes means demoting the A-race to a B-race and pointing the season at something six weeks later. It occasionally means accepting a slower race and enjoying it anyway. What it almost never means is taking the missing weeks out of the taper, which is the first thing athletes reach for and reliably the worst available trade.

Building the season plan backward from your race and rebuilding it whenever reality intervenes is exactly the job PaceBeats automates: it holds the annual plan against your real race date and your actual completed training, and re-derives the weeks ahead from where you are now rather than where the original plan assumed you would be.

Common repairs

Rough guidance for the disruptions that actually happen. All of these are practical rules of thumb rather than precise physiology.

• Missed two or three sessions. Do nothing. Carry on with the week as written and do not try to make them up — a compressed week costs you more than the sessions were worth. There is more on this in what to do about missed workouts.
• A week off with a head cold, no fever. Return with three or four easy days, then resume the block roughly where you left it. A week of lost training costs far less fitness than it feels like it does.
• Two weeks or more, or anything with a fever. Assume you have lost real fitness and, more importantly, that your tolerance for intensity has dropped further than your endurance has. A reasonable rule: spend about as many easy weeks rebuilding as you spent sick before reintroducing hard sessions, then re-plan the rest around the new starting point.
• A month of chaos — work, travel, a new baby. Change the target, not the taper. Move the A-race, downgrade it, or pick a shorter distance at the same event. All three beat arriving at a race you are undertrained for.
• Persistent flatness with no obvious cause. Stop adding load and read the signs of overtraining before you plan anything else. A season plan cannot fix a recovery problem.

Can you just race all year?

You can race often. You cannot peak often. Short-course athletes and anyone in a warm climate can hold a broad level of fitness most of the year and drop into sharpness a handful of times. What breaks people is an unbroken build for eight or nine months with no transition and no genuinely easy weeks — which rarely ends in a dramatic collapse and usually ends in a slow flattening, where every race is a little slower than the last and nobody can say why. Plan at most two peaks, and take one real off-season somewhere in the calendar.

The one-page version

Pick your A-race and put it on the calendar. Label everything else B or C, and actually honor the labels. Count backward: taper, build, base, and start where you are. Write the recovery weeks in before anything else. Move gradually from general work to work that looks like your race. Let the load climb in a sawtooth and peak a few weeks out, not on race week. And when the plan breaks — which it will — re-plan from today's fitness toward the same race date, rather than trying to resume a week that was written for a version of you who did not get sick.