30 weeks

Intermediate Ironman Program - 30 Weeks

Intermediate Ironman triathlon training plan: 30 weeks, 12 to 20 hours a week, building up to a 6h ride and a 3h run. 3.8 km swim, 180 km bike, 42.2 km run.

Intermediate Ironman plan at a glance

30 weeks · 12-20 h/week · 8-10 sessions

Consistent volume over several months, very long sessions and full rehearsal of the fuelling plan. The plan starts from a 2.5 km swim, a 3h ride and a 1h30 run, and builds to 4 km, 6h and 3h.

How this Ironman plan is built

More than ten hours of effort: fuelling, steady pacing and mindset count as much as fitness.

Long session progression

The long ride grows from 3h to 6h and the longest run from 1h30 to 3h, step by step.

Lighter weeks

One week in 4, volume drops by about a third to absorb the previous weeks of work.

Bricks

From week 12, one bike-run brick a week, up to 5h + 1h.

Intensity

2 quality sessions a week in the build phase; everything else is endurance (Z1-Z2).

Prerequisites and Required Level

To follow this intermediate Ironman plan from week one:

Swim 2.5 km without stopping

Ride 3h at endurance pace

Run 1h30 continuously

Have 12 to 20 hours a week available

Completed at least 1 triathlon

Mastered T1 and T2 transitions

Detailed Training Phases

30 weeks in four phases. Durations are those of the longest sessions at the start and end of each phase.

Base Phase

Weeks 1-11

Settle into consistent volume and a solid aerobic base

Objectives:

  • Continuous swim: 2.5 km → 2.6 km
  • Long ride: 3h → 3h55
  • Longest run: 1h30 → 1h55

Key workouts:

  • •1 technique or pace session(s) a week, the rest in Z2
  • •Swim: 3 x 400 m steady, 30 s rest
12-16 hours / week85 % Z1-Z2, 15 % Z3-Z5

Build Phase

Weeks 12-20

Extend long sessions and train the gut to eat on the bike

Objectives:

  • Continuous swim: 2.6 km → 3.4 km
  • Long ride: 3h55 → 5h05
  • Longest run: 1h55 → 2h35

Key workouts:

  • •Swim : 5 x 400 m steady, 30 s rest
  • •Bike : 3 x 30 min in Z3, 10 min easy
  • •Run : 3 x 15 min at marathon pace, 3 min jog
  • •Brick : 3h30 + 40 min
16-20 hours / week80 % Z1-Z2, 20 % Z3-Z5

Race-Specific Phase

Weeks 21-27

Rehearse race day: very long sessions and the full fuelling plan

Objectives:

  • Continuous swim: 3.4 km → 4 km
  • Long ride: 5h05 → 6h
  • Longest run: 2h35 → 3h

Key workouts:

  • •Swim : 3 x 1000 m at race pace, 1 min rest
  • •Bike : long ride with 3 h at race pace and full fuelling
  • •Run : long run with 2 x 20 min at marathon pace
  • •Brick : 5h + 1h
19-20 hours / week75 % Z1-Z2, 25 % Z3-Z5

Taper Phase

Weeks 28-30

A long taper to clear months of fatigue

Objectives:

  • Long ride cut to 3h
  • Longest run: 1h30
  • Last hard session early in week 30

Key workouts:

  • •Short reminders: long ride with 3 h at race pace and full fuelling at half volume
  • •Open water swim if possible
9-12 hours / week80 % Z1-Z2, 20 % Z3-Z5

Detailed Sample Week

Week 16 of 30, in the middle of the build phase: 8 to 10 sessions. Sessions can move to another day, but keep an easy day after the hardest one.

Training zones:

Z1 = Recovery (Very easy)
Z2 = Endurance (Easy)
Z3 = Tempo (Moderate)
Z4 = Threshold (Hard)
Z5 = VO2max (Maximum)
Monday
Rest
Full rest.
--
Tuesday
Threshold swim
5 x 400 m steady, 30 s rest
Z3-Z43.2 km
Wednesday
Bike intervals
3 x 30 min in Z3, 10 min easy
Z2-Z42h40
Thursday
Run session
3 x 15 min at marathon pace, 3 min jog
Z3-Z41h50
Friday
Endurance swim
Continuous easy swim.
Z22.8 km
Saturday
Long ride
Last hour in Z3 on even weeks.
Z24h50
Sunday
Brick or long run
Alternate every other week.
Z2-Z33h30 + 40 min / 2h25

Key Program Workouts

The sessions not to miss, in their intermediate version for an Ironman.

Swimming

Threshold (build)

1x/week

5 x 400 m steady, 30 s rest

Builds the continuous swim towards 4 km

Race pace (specific)

1x/week

3 x 1000 m at race pace, 1 min rest

Locks in race pace

Cycling

Long ride

1x/week

Up to 6h in Z2

Endurance and fuelling practice

Intensity

1x/week

3 x 30 min in Z3, 10 min easy → long ride with 3 h at race pace and full fuelling

Hold race pace on the bike

Running

Long run

1x/week

Up to 3h in Z2

Running endurance

Quality

1x/week

3 x 15 min at marathon pace, 3 min jog → long run with 2 x 20 min at marathon pace

Race pace on tired legs

Brick

Bike then run

1x/week from week 12

5h + 1h at peak

Gets the legs used to running off the bike

Technique in pictures

Reference road position: soft elbows, knee still bent at the bottom of the stroke, stable torso angle. Saddle height moves of ±5 mm change everything — have it checked by a shop or bike fitter.

Nutrition for an Ironman

An Ironman takes 10h-13h at this level: needs change with the length of the effort.

Rides over 4 hours

Train the gut to take 60 to 90 g of carbohydrate per hour for several hours. It is trained just like the legs.

Race day

Write an hour-by-hour plan: carbohydrate, water and salt. Follow it from the first hour on the bike, before you feel hungry or thirsty.

Marathon

Plan to eat and drink at every aid station. Any product offered on course should have been tested in training.

Equipment for an Ironman

Essentials first; the rest can wait for a second race.

Swim

Essential
  • Wetsuit that does not chafe over 3.8 km
Optional
  • ○Anti-chafe cream

Bike

Essential
  • Position validated on 5-hour rides
  • Repair kit
Optional
  • ○Tri bike
  • ○Power meter to hold your pace

Run

Essential
  • Shoes tested on your longest runs
Optional
  • ○Gel belt
  • ○Special needs bags prepared in advance

Common Mistakes to Avoid

The most frequent mistakes on an Ironman at intermediate level.

Eating too late

Solution: A deficit built on the bike cannot be recovered in the marathon: eat from the first hour.

Stacking heavy weeks without recovery

Solution: Over several months, lighter weeks prevent burnout and injury.

Doing every session at the same intensity

Solution: Easy sessions must stay easy so the quality sessions can be done well.

Frequently Asked Questions

This plan lasts 30 weeks: base in weeks 1-11, build in 12-20, race-specific work in 21-27 and taper in 28-30. It takes 12 to 20 hours a week over 8 to 10 sessions.

At the peak of the race-specific phase: a 4 km continuous swim, a 6h ride, a 3h run and a brick of 5h on the bike followed by 1h of running.

In an average 16-hour week: about 2.5 h of swimming, 9 h of cycling and 5 h of running. For an Ironman, cycling takes the biggest share because it is the longest leg of the race (3.8 km swim, 180 km bike, 42.2 km run).

This plan adds 2 quality sessions a week in the build phase, for example 3 x 30 min in Z3, 10 min easy on the bike and 3 x 15 min at marathon pace, 3 min jog on the run. A time of 10h-13h is common at this level; most of the gain comes from doing those sessions consistently.

Pick the plan up at the current week without making up lost sessions. The plan has a lighter week every 4 weeks: if you missed more than 10 days, repeat the last completed week before moving on.

As a guide: 13h-17h for a first Ironman, 10h-13h at intermediate level, under 10h for the fastest. More than ten hours of effort: fuelling, steady pacing and mindset count as much as fitness.

Three landmarks: elbows bent (90–110°) to absorb shocks and relax the shoulders, knee still bent around 140–150° at the bottom of the pedal stroke (saddle height), stable back angle around 40–45°. Knee or neck pain is a fit problem: have it checked — ±5 mm of saddle height changes everything.

Get the Intermediate Ironman plan as a PDF

Free, sent by email: the 30 weeks of the intermediate Ironman plan.

Get my plan