Key takeaways

  • The bike-to-run transition (T2) is where most triathletes lose the most time relative to their standalone run fitness. The AI programs bricks that progressively teach your legs to fire at run pace after cycling effort.
  • Research shows that run performance degrades 3-8% immediately after cycling due to neuromuscular fatigue and altered muscle recruitment patterns (Millet & Vleck, 2000, Sports Medicine). Brick training reduces this deficit.
  • Not every week needs a full brick. The AI varies brick intensity and duration across your training cycle - short easy bricks in base phase, race-specific bricks in build phase, and sharp dress rehearsals before race week.
  • The first 1-2km off the bike are the hardest. The AI tracks your pace data in that window specifically and programs sessions that target settling into race pace within the first kilometer.

AI Coach for Brick Workout Training

Running off the bike feels terrible until your body learns to handle it. Your AI coach programs progressive brick sessions that build T2 fitness systematically, so race day is not the first time your legs cooperate.

Progressive brick building

The AI starts with short, easy runs off moderate bike efforts and progressively increases both the bike intensity and run duration over your training block. Early bricks teach basic adaptation. Later bricks simulate race demands with target power on the bike followed by target pace on the run.

Race-specific pacing targets

Every brick session has specific power and pace targets based on your FTP and run threshold. The AI sets your bike NP and run pace for each brick, tracks how well you hit them, and adjusts future targets based on your progression. You know exactly what race-day pacing should feel like.

T2 pace analysis

The AI analyzes your first 1-2km run splits off the bike across all brick sessions. It tracks whether your settle-in time is improving and flags if your early pace is too fast (positive splitting) or too conservative. Over time, you learn exactly how to execute the critical first minutes of T2.

Brick frequency and placement

Too many bricks create excessive fatigue. Too few leave you unprepared for T2. The AI programs 1-2 bricks per week during the build phase and reduces frequency during recovery weeks. It places bricks on days when your recovery data supports a demanding session.

Frequently asked questions

How often should I do brick workouts?

During the build phase, 1-2 per week is typical. In base phase, one easy brick every 1-2 weeks is enough. The AI adjusts frequency based on your recovery capacity and how far out your race is. More is not always better - quality and specificity matter more than just stacking bricks.

How hard should the bike portion of a brick be?

It depends on the training goal. Easy bricks use 65-75% FTP on the bike. Race-specific bricks use your target race power (70-85% FTP depending on distance). The AI sets specific power targets for each brick and tracks your ability to hit run pace after different bike intensities.

How long should the run portion be?

Early in training, 10-20 minutes is enough to get the neuromuscular adaptation. As you progress, runs extend to 30-60 minutes at race pace. For Ironman athletes, some bricks include longer runs. The AI scales run duration based on your target race distance and where you are in the training cycle.

Why do my legs feel so heavy off the bike?

Cycling primarily uses your quads in a concentric pattern, while running demands eccentric loading and a different muscle recruitment sequence. The transition creates neuromuscular confusion that your body adapts to with practice. The AI programs enough bricks to drive this adaptation without overtraining.

Should I practice swim-to-bike transitions too?

T1 is less physiologically demanding than T2 since swimming and cycling use different muscle groups. However, the AI can include swim-to-bike bricks before key races to practice the logistics: wetsuit removal, mounting, and settling into bike rhythm quickly. Most training bricks focus on bike-to-run since that transition has the biggest performance impact.

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