Do you need brick workouts for a triathlon?
You rack the bike and start to run. Your legs feel like someone else's. They are heavy and stiff, and your breathing is all over the place. This is why triathletes call a ride followed straight by a run a brick. Many triathlon plans include them. So do you need brick workouts for a triathlon?
The short answer is no. Running after a ride does cost more, mostly in the first few minutes. Most of the slower run is tiredness from the ride. No study shows that brick training makes your race run faster. Here is what the studies found.
01
The first minutes off the bike cost more.
In one study, 7 triathletes rode 40 km and then ran 10 km. On another day they ran the same 10 km at the same speed with no ride first. After the ride, their heart beat about 7 beats a minute faster. They also breathed harder and used more oxygen.
Most of that settled quickly. Heart rate levelled out in about a minute and oxygen use in about two. Breathing took about seven. Their stride length and stride rate did not change at all.
A review of the research found that running after a ride costs between 1.6 and 11.6 percent more energy. It depends on the athlete. Most of the way people run stays the same. The main change is that they lean further forward.
02
Most of the slower run is the ride's tiredness.
In a study of 8 triathletes, each rode hard and steady for 65 minutes. Then they ran 10 km. On another day they ran the 10 km fresh. After the ride, they ran it about four and a half minutes slower. Pedalling faster or slower on the bike made no difference.
How hard you ride matters more. In a sprint triathlon study, 8 international triathletes rode at the same speed twice. Once they rode alone. Once they rode sheltered behind another rider, which is much easier. After the easier ride, they ran faster: 17.8 km an hour against 17.1.
A third study had 8 club triathletes race 40 km on the bike and then run. Their running economy, the oxygen a given speed costs, did not change. They just had to work harder to hold the same speed.
No study has shown that brick training makes the run off the bike faster.
03
The strange legs pass within minutes.
One study looked at 15 moderately trained triathletes. They rode for 15 minutes and then ran for 30. The way their muscles fired changed in only one of them. In five, the angles of their hips, knees or ankles shifted by about three degrees. In all but one, that was gone within five minutes.
A second study did the same with 7 elite international triathletes. They rode easy for 20 minutes, or hard for 50. Afterwards they ran just as they did fresh. Their muscles, joint angles and oxygen cost were all the same.
These elite athletes have done years of riding and running. Many of them have done bricks too. The studies cannot tell which of the two kept their running the same.
04
The one training study is small.
We found one study that tested brick training against separate sessions. Twelve college triathletes trained for six weeks. One group did two hours a week of short rides and runs in turns. The other did the same two hours as a separate ride and a separate run.
The brick group's knees moved a little less rigidly in the first minute of a run after riding. Nothing else changed. The groups were only six people each, and they did not start out the same. The study did not measure how fast anyone ran.
That is not proof that bricks do nothing. It means nobody has shown that they do anything a separate ride and run would not.
05
What builds the run off the bike.
The run off the bike is slower because you are tired from everything before it. So the run depends on how much the ride takes out of you. The fitter you are on the bike, the less a race-day ride costs you. Then you have more left to run.
That fitness comes from riding and running, each at its own effort, week after week. Base rides and runs build most of it. On race day, ride at an effort you can hold, and start slower than you want to.
Then expect the first minutes of the run to feel strange. Run them easy and let your breathing settle. In the studies, after rides of up to 40 km, that passed within minutes. After a longer ride it may take a little longer.
If you want to know the feeling before race day, run a few easy minutes after a ride once. It will show you what to expect. It will not build anything a separate run would not.
Why your weekly hours matter more than any one session is in It is the weeks that get you ready.
Sources (8)
- Millet and Vleck 2000. British Journal of Sports Medicine 34:384-390. The cycle to run transition in Olympic triathlon, a review.
- Hue et al. 1997. European Journal of Applied Physiology 77:98-105. Running after cycling compared with running alone in 7 triathletes.
- Tew 2005. Journal of Sports Science and Medicine 4:342-353. Cycling cadence and the 10 km run that follows, in 8 triathletes.
- Hausswirth et al. 1999. Medicine and Science in Sports and Exercise 31:599-604. Riding alone or behind another rider, and the run that follows.
- Stewart et al. 2022. BMC Sports Science, Medicine and Rehabilitation 14. A 40 km ride and the run that follows, in 8 club triathletes.
- Bonacci et al. 2010. Journal of Sports Sciences 28:1477-1487. Running after cycling in 15 moderately trained triathletes.
- Bonacci et al. 2011. Sports Biomechanics 10:59-71. Running after cycling in 7 elite international triathletes.
- Haworth et al. 2010. 28th International Conference on Biomechanics in Sports. Six weeks of brick training compared with separate rides and runs, in 12 college triathletes.