Ironman Bike Workouts: 10 Example Training Sessions

Summary:
This post presents 10 example Ironman bike training sessions designed to develop endurance, pacing control and durability across the 180 km (112 mile) bike leg. Each session targets a specific aspect of Ironman bike execution, from aerobic base development to race-specific tempo and controlled intensity work. Used within a structured training plan, these workouts help athletes practise sustained power, fuelling discipline and execution under fatigue, supporting a controlled bike leg and a stronger run on race day.

The Ironman Bike Leg

The Ironman bike leg is not simply about producing power. It is a test of restraint, pacing discipline and decision-making under sustained load. Riding 180 km (112 miles) at race intensity requires athletes to balance effort with fuelling, terrain and environmental conditions while preserving the ability to run well afterwards. Early pacing errors or unnecessary surges may feel manageable in the moment but often carry significant consequences later in the race.

Strong Ironman bike preparation prioritises durability and control rather than just peak numbers in isolation. Training must develop the ability to hold steady power for extended periods, manage effort across changing terrain and maintain fuelling consistency under pressure. When pacing, nutrition and execution are trained together, riding becomes calmer and more repeatable. These example bike workouts are designed to build the physical resilience, pacing confidence and control required to ride efficiently and arrive at the marathon ready to execute rather than recover.

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Ironman Bike Training Zones: FTP, HR and Effort Guide

Understanding your bike training zones is essential for executing Ironman preparation with precision rather than guesswork. Across a 180 km (112 mile) bike leg, the ability to control effort determines whether power remains sustainable or gradually unravels under fatigue. Using power, heart rate and perceived effort together allows athletes to align each session with a clear purpose, ensuring intensity stays appropriate while recovery and fuelling demands remain manageable across long and demanding training weeks.

FTP or Functional Threshold Power, represents the highest average power an athlete can sustain at threshold intensity for approximately one hour and is used as a reference point for defining cycling zones and expressing intensity relative to sustainable effort. Heart rate measures how frequently the heart beats per minute and reflects the body’s internal response to effort. In training, it is used to estimate how hard the cardiovascular system is working relative to an athlete’s maximum or threshold heart rate. RPE or Rate of Perceived Exertion, describes how hard a session feels to the athlete on a subjective scale and provides a practical reference for translating internal sensations of effort into usable training intensity. When these tools are used together, they support controlled, repeatable training that closely reflects Ironman race demands rather than isolated performance metrics.

Training Metrics and Intensity Guidelines

• Zone 1 / Recovery: (<55% FTP, 68–73% MHR, 1–2 RPE)
  Effort: Very easy
  Use: Warm-ups, cool-downs, recovery days
  Check out: What Is Zone 1 / Recovery?

• Zone 2 / Endurance: (56–75% FTP, 73–80% MHR, 3–4 RPE)
  Effort: Easy
  Use: Long rides, base runs, aerobic swims
  Check out: What Is Zone 2 / Endurance?

• Zone 3 / Tempo: (76–90% FTP, 80–87% MHR, 5–6 RPE)
  Effort: Moderately hard
  Use: Tempo intervals, steady-state efforts
  Check out: What Is Zone 3 / Tempo?

• Zone 4 / Threshold: (91–105% FTP, 87–93% MHR, 7–8 RPE)
  Effort: Hard
  Use: Sustained intervals, Lactate management
  Check out: What Is Zone 4 / Threshold?

• Zone 5 / VO2 Max: (106–120% FTP, 93–100% MHR, 9–10 RPE)
  Effort: Very hard
  Use: Short intervals, fast repetitions, peak sharpening
  Check out: What Is Zone 5 / VO2 Max?

• Use the FLJUGA Training Zone Calculator to calculate your max heart rate to find your exact Zones.

Applied consistently, these bike training zones help Ironman athletes distribute effort intelligently across the full training spectrum. Easier sessions support recovery and durability, while higher intensity work strengthens pacing control and fatigue resistance without overwhelming the system. While Zone 3 and Zone 4 are used strategically in Ironman training, race-day bike pacing for most athletes sits in Zone 2 to Zone 3 depending on experience, terrain and conditions. When power, heart rate and perceived effort are respected together, training becomes calmer, more sustainable and far more effective at preparing the body for the demands of riding 180 km (112 miles) with control and purpose on race day.

This may help you: Triathlon Training Zones 1–5 Explained: Why They Matter

The 10 Example Ironman Bike Sessions

1. Long Endurance Ride

• Purpose: Build aerobic capacity and train fuelling over race duration

• Warm-Up: 15 min spin

• Main Set: 3–4 hr @ Zone 2

• Cool-Down: 10 min easy spin

2. Broken Tempo Ride

• Purpose: Accumulate steady race-pace work in manageable blocks

• Warm-Up: 15 min spin

• Main Set: 3 x 30 min @ Zone 3 (10 min easy spin between)

• Cool-Down: 10 min easy spin

3. Controlled Threshold Blocks

• Purpose: Increase top-end aerobic power under fatigue

• Warm-Up: 15 min spin

• Main Set: 2 x 20 min @ Zone 4 (5 min easy spin between)

• Cool-Down: 10 min easy spin

4. Over-Under Intervals

• Purpose: Train body to shift between tempo and threshold demands

• Warm-Up: 15 min spin

• Main Set: 5 x (5 min @ Zone 3 + 5 min @ Zone 4) (5 min easy spin between)

• Cool-Down: 10 min easy spin

5. Big Gear Endurance

• Purpose: Build muscular strength and steady-state control

• Warm-Up: 15 min spin

• Main Set: 4 x 15 min @ Zone 2 in a big gear (low cadence) (5 min easy spin between)

• Cool-Down: 10 min easy spin

6. Progressive Race Prep Ride

• Purpose: Progress effort through race-day zones to simulate build

• Warm-Up: 15 min spin

• Main Set: 30 min @ Zone 2 + 20 min @ Zone 3 + 10 min @ Zone 4

• Cool-Down: 10 min easy spin

7. Long Tempo Ride

• Purpose: Sustain Ironman pacing under controlled pressure

• Warm-Up: 15 min spin

• Main Set: 75 min @ Zone 3

• Cool-Down: 10 min easy spin

8. Brick Simulation Ride

• Purpose: Prepare for Ironman bike-to-run transition

• Warm-Up: 15 min spin

• Main Set: 2 x 20 min @ Zone 3 + 15 min @ Zone 4 (5 min easy spin between)

• Cool-Down: 10 min easy spin (Transition easy jog optional)

9. Tempo + Threshold Combo

• Purpose: Combine mid-race control with strong finishing effort

• Warm-Up: 15 min spin

• Main Set: 40 min @ Zone 3 + 15 min @ Zone 4

• Cool-Down: 10 min easy spin

10. Indoor Trainer Session

• Purpose: Hit key intensities with high control and no coasting

• Warm-Up: 15 min spin + 3 x 1 min build

• Main Set: 4 x 6 min @ Zone 4 (3 min easy spin between)

• Cool-Down: 10 min easy spin

Why These Bike Sessions Work

These bike sessions work because they are designed around the realities of Ironman racing rather than ideal conditions or fresh legs. Each session develops the ability to manage power, pacing and decision-making under prolonged fatigue, which ultimately determines bike execution across 180 km (112 miles) and strongly influences marathon performance. By prioritising controlled endurance work, sustained tempo efforts and race-relevant intensity, these sessions train athletes to deliver steady power when efficiency and restraint matter most.

The sessions also reinforce consistency and discipline across long training blocks. Endurance rides build durability, structured intensity improves fatigue resistance and pacing-focused sessions teach control over extended durations. Importantly, these bike sessions create repeated opportunities to practise fuelling strategy, timing and focus at realistic intensities. When trained together within a structured plan, these elements produce a bike leg that feels controlled rather than reactive, allowing athletes to dismount composed and prepared to execute the marathon rather than recover from the ride.

This may help you: How to Train for an Ironman: The Complete Training Guide

Common Mistakes with Ironman Bike Training Sessions

Ironman bike training sessions are designed to develop durability, pacing discipline and execution across 180 km (112 miles). When these sessions are misused or misunderstood, they can quietly undermine consistency, fuelling practice and run readiness. Avoiding the following mistakes helps ensure bike sessions build long-term performance rather than short-term fatigue.

• Riding sessions harder than intended:
  Ironman bike sessions are built around specific intensity targets and execution goals, not maximum effort. Pushing power beyond the prescribed range turns controlled work into unnecessary fatigue, reducing the quality of subsequent sessions and compromising the ability to run well after long rides.

• Treating every session as race simulation:
  Not every bike session is meant to replicate race day. Using race-level focus and intensity on every ride blurs the purpose of endurance, tempo and recovery work. Ironman preparation requires clear separation between session types so adaptations can accumulate without overwhelming the system.

• Ignoring fuelling during longer sessions:
  Longer Ironman bike sessions are the primary opportunity to rehearse race-day fuelling in training. Skipping fuelling or treating it casually means intake strategy, timing and execution are never tested under realistic conditions, forcing athletes to improvise on race day rather than execute a rehearsed plan.

• Chasing peak numbers instead of steady output:
  Focusing on average power targets or short power spikes rather than sustained control encourages surging and pacing errors. Ironman bike performance depends on holding steady power over long durations, not producing isolated high outputs that increase fatigue cost.

• Failing to respect recovery after key sessions:
  Ironman bike sessions place significant load on the system. Stacking demanding rides without adequate recovery reduces adaptation and increases accumulated fatigue across the week. Recovery allows key sessions to be repeated with quality rather than survived.

• Using sessions without plan context:
  These bike sessions are most effective when placed deliberately within a structured training plan. Using them randomly or too frequently can disrupt training balance and progression. Session choice and timing should always align with the current phase of Ironman preparation.

When Ironman bike sessions are executed with intent, discipline and appropriate recovery, they build confidence, pacing control and durability across long training blocks. By respecting session purpose and prioritising execution over ego, athletes develop bike fitness that supports strong marathon performance rather than undermining it.

This may help you: Ironman Triathlon Explained: The Complete Beginner’s Guide

FAQ: Ironman Bike Training Sessions

How many bike sessions per week should I do when training for an Ironman?
Most Ironman training plans include three to four bike sessions per week, depending on experience, available training time and recovery capacity.

What is the most important bike session in Ironman training?
Long endurance and steady tempo rides are the most important bike sessions because they develop sustained power and pacing control across the full 180 km bike leg.

Should all Ironman bike sessions be ridden at race intensity?
No, Ironman bike training should include a mix of endurance, tempo and higher-intensity work rather than riding every session at race effort.

How long should long bike rides be for Ironman training?
Long ride duration depends on the structure of the training plan, with the focus on pacing control and fuelling practice rather than repeatedly matching race distance.

How important is fuelling practice during Ironman bike training?
Fuelling practice is essential because long bike sessions allow athletes to rehearse race-day intake strategy and timing under realistic conditions.

How does bike training affect the Ironman marathon?
Controlled pacing and fuelling on the bike reduce fatigue and help athletes start the marathon in a more composed and executable state.

FURTHER READING: Ironman Sessions

• Ironman Training: What Is Zone 2 / Endurance?

• Ironman Training: What Is Zone 3 / Tempo?

• Ironman Training: What Is Zone 4 / Threshold?

• Ironman Training: What Is Zone 5 / VO2 Max?

Ironman Sessions

• Ironman Run Training: 10 Essential Sessions

• Ironman Swim Training: 10 Essential Sessions

• Ironman Training: Recovery Week

• Ironman: Beginner’s Guide

Final Thoughts

Effective Ironman bike training is built on execution, control and repeatability rather than just chasing peak numbers or isolated efforts. The sessions in this guide are designed to develop sustained power, pacing discipline and fuelling consistency across the 180 km (112 mile) bike leg while supporting run readiness rather than compromising it. When used within the structure of a well-designed training plan, these bike sessions help athletes ride with intent, manage effort intelligently and arrive at the marathon composed and prepared to execute rather than simply having survived the ride.

Always consult with a medical professional or certified coach before beginning any new training program. The information provided is for educational purposes only and is not a substitute for personalized advice.