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Brick Workout

A brick workout combines two disciplines back-to-back in triathlon training, typically cycling followed by running. Learn why brick workouts matter and how to do them effectively.

Quick Answer

Brick WorkoutA brick workout is a training session that combines two disciplines back-to-back, most commonly cycling immediately followed by running. The name comes from how your legs feel "like bricks" when you start running after cycling.

What is a Brick Workout?

In triathlon training, a brick workout involves transitioning directly from one sport to another without rest. The most common brick is a bike-to-run (bike/run) workout, simulating race conditions.

Why "brick"? Three theories:

  1. Your legs feel like bricks when running after biking
  2. "BRun + bIKe" = BRICK
  3. Building "bricks" of fitness

Regardless of origin, bricks are essential for triathlon success.

Types of Brick Workouts

Bike-Run Brick (Most Common)

FormatBikeRunPurpose
Short30-60 min15-20 minTransition adaptation
Moderate60-90 min30-40 minRace simulation
Long2-4 hours45-60 minIronman prep
IntensityRace paceRace paceSpecific preparation

Other Brick Combinations

Brick TypeUse Case
Swim-BikePractice swim-to-bike transition
Swim-RunAquathlon or specific focus
Run-BikeOccasionally for variety
Triple brickAll three in sequence

Read our complete guide: Brick Workouts for Triathlon.

Brick workouts are integrated into structured triathlon training. Our 8-Week Sprint Triathlon Training Plan includes progressive brick sessions starting from week 2.

Why Bricks Matter

1. Transition Adaptation

Your body needs to learn to run on tired cycling legs:

Physiological ShiftWhat Changes
Blood redistributionFlow shifts to running muscles
Muscle recruitmentDifferent firing patterns
Heart rateTypically higher initially
CadenceOften lower initially

2. Mental Preparation

Bricks teach you:

  • What running off the bike actually feels like
  • How to pace through the "brick legs" phase
  • Confidence for race day

3. Practical Skills

Practice:

How to Structure Brick Workouts

Beginner Brick

PhaseDurationIntensity
Bike30-45 minModerate
Transition5 min maxQuick change
Run15-20 minEasy pace

Goal: Adapt to the feeling, not performance.

Intermediate Brick

PhaseDurationIntensity
Bike60-90 minRace effort
Transition2-3 minRace rehearsal
Run30-40 minGoal race pace

Goal: Build race-specific fitness.

Race Simulation Brick

PhaseDurationIntensity
BikeRace distanceRace pace
TransitionRace speedPractice routine
Run50-75% race distanceSlightly faster

Goal: Rehearse race day exactly.

Brick Workout Tips

Managing "Brick Legs"

The heavy, dead-leg feeling typically:

  • Peaks in first 5-10 minutes of run
  • Subsides as blood redistributes
  • Improves with practice

Strategies:

  • Start run slower than goal pace
  • Focus on cadence, not pace
  • Run the first mile by effort, not speed
  • Use quick transition to maintain flow

Cadence Focus

Maintain high running cadence (170+) off the bike:

  • Prevents overstriding
  • Keeps legs turning over
  • Reduces impact when muscles are fatigued

Nutrition Considerations

TimingNutrition Strategy
During bikePractice race nutrition
Late in bikeTake last nutrition 15-20 min before transition
Start of runCarry gel/hydration if needed

Sample Brick Workouts

Sprint Triathlon Prep

  • Bike: 40 min with 2×10 min at race effort
  • Quick change
  • Run: 20 min with 10 min at race pace

Olympic Distance Prep

  • Bike: 75 min with final 30 min at race pace
  • T2 practice
  • Run: 40 min as 10 easy + 20 race pace + 10 easy

Half Ironman Prep

  • Bike: 2.5-3 hours with race-paced final hour
  • Quick T2
  • Run: 45-60 min at half ironman pace

Brick Frequency

Training PhaseBricks per Week
Base1 (optional)
Build1-2
Race-specific1-2
Taper1 (short)

Most triathletes benefit from one focused brick per week, not more.

Common Brick Mistakes

1. Starting Run Too Fast

Your legs will feel terrible initially—trust the process and start slow.

2. Too Many Bricks

Bricks are stressful. One per week is enough for most athletes.

3. Ignoring Recovery

Bricks combine training stress of two sports. Account for this in weekly planning.

4. Skipping T2 Practice

Always practice the actual transition, not just the sports.

Common Questions

How often should I do bricks?

Once per week during build phase is sufficient for most triathletes. More bricks means more fatigue without proportionally more benefit.

When should I start doing bricks?

Introduce short bricks 8-12 weeks before your race. Earlier in training, focus on building single-sport fitness.

Should bricks be race pace?

Not always. Recovery bricks (easy bike + easy run) build adaptation without excessive fatigue. Mix easy and harder bricks throughout your training.

Why do my legs feel so bad?

Normal! Blood pools in cycling muscles and must redistribute for running. This improves with practice—that's why bricks exist.

Disclaimer: Information provided by this site is for educational purposes only and is not intended to be a substitute for professional medical advice specific to the reader's particular situation. The information is not to be used for diagnosing or treating any health concerns you may have. The reader is advised to seek prompt professional medical advice from a doctor or other healthcare practitioner about any health question, symptom, treatment, disease, or medical condition.