Last updated: 3 October 2026
Reviewed by Jordan Morley, FA Level 2 Football Coach
Brick training gets its name from the ‘brick legs’ sensation when switching from cycling to running — legs feel heavy and unresponsive for the first 5-10 minutes of the run as muscles adapt from the circular pedalling motion to the linear running gait. Bike-to-run bricks are the most common and essential triathlon training session. Regular brick sessions reduce the transition impairment and train the neuromuscular system to switch movement patterns. Swim-to-bike bricks are also used but less common.
- Bike immediately followed by run
- Named for the heavy ‘brick legs’ sensation
- Reduces T2 transition impairment
- Essential for Olympic, 70.3 and Ironman preparation
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Brick sessions exist because the bike-to-run transition in triathlon feels physically unlike running on fresh legs — cycling-specific muscle fatigue and altered blood flow make the first mile off the bike feel awkward and heavy even for strong runners, so practising this specific transition regularly is considered essential triathlon-specific training, not just general fitness work.
FAQ
How often should triathletes do brick workouts?
Most training plans include one brick session per week, especially in the weeks leading up to a race, to practice the specific sensation of running on bike-fatigued legs.
Does brick training need to be long?
No — even a short 10-15 minute run immediately after a bike session provides meaningful transition-specific adaptation; the key is practising the transition itself, not logging extra volume.