Triathlon Brick Training Calculator
Plan your bike-to-run brick training sessions.
Calculate target bike and run paces based on your race goals and current fitness.
Brick Training Targets
A brick workout is a training session combining two triathlon disciplines back-to-back, most commonly bike followed immediately by run. The term “brick” likely comes from the heavy, leaden feeling in the legs during the run portion — as if they are made of bricks.
Brick training serves two purposes:
- Physiological adaptation: Training the muscles to switch from the cycling movement pattern (quadriceps-dominant, circular) to running (hamstring and glute activation, linear). This adaptation takes weeks to develop and is sport-specific — running fitness alone does not prepare you for running off the bike.
- Mental practice: Learning to manage the uncomfortable transition period and pace yourself before your legs “come around” (usually after 1–2 km).
Target paces for brick sessions:
- Bike pace: 75–85% of race bike effort. Slightly below race pace to preserve running legs.
- Run pace: First kilometre: 15–20 seconds/km slower than race run pace. After 1–2 km, aim to gradually reach race pace.
Brick session structures by race distance:
- Sprint prep: 30 min bike + 15 min run, 2× per week in the last 4 weeks
- Olympic prep: 60 min bike + 20 min run, 1–2× per week in last 6 weeks
- 70.3 prep: 90–120 min bike + 30–45 min run, 1× per week
- Ironman prep: 3–4 hr bike + 45–60 min run, 1× per week in peak training
The first brick: Expect the run to feel terrible the first few times — this is normal and will improve quickly. Focus on smooth turnover rather than pace for the first few sessions.