A brick session is a training set that involves more than one discipline/sport back-to-back. The most common example in triathlon is the bike/run brick, where a bike session will be followed by a run.
An example could be a 30min road bike ride followed by a 10min run straight away after (you can steadily build up the duration and intensity as your triathlon/duathlon career progresses).
A tri-suit is a great piece of kit for brick sessions as you won’t need to change clothing, while a brick session will also help you practise swapping your bike shoes for running trainers at speed in preparation for race day. Alternatively, you can cycle in your running shoes.
An often-neglected brick session is the swim-to-bike brick, which is logistically tougher, but can be done by cycling to the pool, swimming and then cycling again soon afterwards. Again, this will ready you for the unique challenges of race day when you go from swimming horizontally to riding in a vertical position, which can often lead to dizziness.
Key benefits of a brick session include readying the body’s physiology/muscular adaptation for the unusual combination of performing one discipline after another on race day (and avoiding the dreaded ‘jelly legs’ at the start of the run leg) and teaching you how to run when already fatigued.
Other multisport benefits include speed, strength and endurance, while performing bricks in training will help build your mental confidence for race day.
They’ll also help you prepare for and practise both Transition 1 (T1, swim-to-bike) and Transition 2 (T2, bike-to-run) and let you experiment with your transition set-up and race-day gear in a training situation.