A 12-week plan for experienced duathletes preparing for a 10K/40K/5K race.
Training runs 6–10.25 hours per week and is structured around three priorities: bike power, run threshold, and race-specific transitions.
What's in the plan:

Bike power sessions targeting speed and sustained output on the 40K leg
Lactate threshold runs to raise your sustainable pace across both run legs
BRICK workouts that progressively build your ability to run well off the bike
Race-intensity sessions in the final weeks to simulate actual race conditions

Structure:

Weeks 1–4 — Progressive volume to build aerobic base and muscular endurance
Weeks 5–8 — Threshold runs, harder bike work, and BRICK integration
Weeks 9–12 — Race simulations and a structured taper