Race Hub · First-timer's guide

IRONMAN Portugal-Cascais

Saturday 17 October 2026, Cascais, Portugal. A one-loop 3.8km swim in the Bay of Cascais, a two-loop 179km bike that climbs into the Sintra-Cascais Natural Park and takes in the Estoril Formula 1 circuit, and a three-loop marathon along the Atlantic seafront. A late-season full distance with real climbing and an exposed coast. Here is the actual course, and a pacing plan built for the full distance rather than a doubled-up 70.3.

3.8km sea swim 179.4km bike · 1538m climbing 42.2km rolling run Wetsuit likely

The Bike Course

Two loops, and the climbing is not optional.

The route measures 179.4km with roughly 1,530m of climbing, and almost none of it is flat. Each lap runs out past Guincho and up into the Sintra-Cascais Natural Park, topping out around 195m, before dropping back through Estoril for a lap of the old Formula 1 circuit. Two things decide this bike leg. The first is that you climb the same hills twice, so whatever you spend on lap one you pay for on lap two. The second is the Atlantic: the Guincho coast is famous for wind, and the exposed sections can turn a comfortable position into a fight. We pace you against the real elevation at genuine full-distance intensity, so the marathon is still yours to run.

Pacing Calculator

How do your numbers stack up right now?

Built for first-timers. You don't need to know your FTP. A couple of honest inputs and we'll model your day against the real Cascais course.

Swim CSS pace (per 100m)

Your Critical Swim Speed. We add for open water & wetsuit.

Don't know your CSS? Click Here

Bodyweight (kg)

Height (cm)

Used with your weight for a power-to-weight read. Not stored anywhere.

Your bike engine

Average km/h on a recent long ride, of similar race distance and terrain, at race pace effort.

Recent run time

Your standalone half time, h:mm:ss.

Have you raced this distance before?

Also build my race-day fuelling plan 🍗 Carbs, fluid and sodium for the whole day, worked out from your predicted finish time and the bodyweight you entered above. Just two quick choices.

Expected conditions on the day

Mid-October in Cascais is usually mild rather than hot, roughly 16-24°C. Cool / mild or Warm are the sensible picks; check race week, and respect the wind.

How hard are you racing it?

I'm gut-trained (I've practised up to ~120 g/h)

Predicted finish range

-

Power-to-weight body composition

With around 1,530m of climbing across two identical laps, weight matters more here than on a flat course. Every kilogram is carried up the Sintra climb twice. It is not the whole story, and aerodynamics still rules the exposed coastal sections, but body composition is a real lever at Cascais in a way it is not at Kalmar.

These are just mathematical outcomes from your height and weight, not a judgement on your body, and the maths can't tell how much of your weight is muscle. Any change should come from better fuelling and training, never restriction or dropping weight for its own sake, under-eating to chase "race weight" costs you more fitness than it buys. Whether it applies to you at all, and what a healthy target looks like, is exactly what our coaching team, with Adam on nutrition, work out with you 1:1.

Adam Glover · Performance Nutritionist

Level 4 Nutrition Coach (BTN Academy) and part of the TC Coaching team. Every Team TC Coached Athlete gets to work 1:1 with Adam, not just on everyday nutrition, but on body composition and race-day fuelling for events exactly like this.

Apply for 1:1 coaching

Don't go it alone.

These headline numbers are a great start, but race day is bigger than a set of splits. What gets you to the line ready, and across it in the best possible shape, is a coaching team in your corner: mapping and running the whole journey with you across training, strength and conditioning, nutrition and race-day strategy, built around your life and adjusted as you go. That is exactly what Team TC does.

Apply for 1:1 coaching with Tom

Before race day