Race Hub · First-timer's guide

IRONMAN 70.3 Weymouth

Sunday 20 September 2026. A sea swim in Weymouth Bay, a genuinely honest bike, and a flat seafront run. Here's the real course, and a pacing plan built against its actual elevation, not a flat-or-hilly guess.

1.9km sea swim 90.9km bike · 971m climbing 21.1km flat run Wetsuit likely

The Bike Course

Honest about the climbing.

A single loop into the Dorset countryside with repeated short, sharp climbs, no monster passes, but no free-wheeling either. We pace you against the elevation from the official IRONMAN bike GPX, 971m of climbing across 90.9km, rather than a flat-or-hilly guess. Respect it early and it rewards you on the 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 Weymouth course.

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

Don't know your CSS? Click Here

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

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

Your standalone half time, h:mm:ss.

Weymouth in September is usually cool to mild.

Predicted finish range
-

Power-to-weight body composition

Weymouth climbs, and on the hills your speed is governed by power-to-weight: the watts you can hold for every kilo you carry up the road. Same power, less weight, and you go up faster, which is why body composition matters more here than on a flat course.

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
Adam Glover · Integrated Nutrition
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