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The Key to Running Well in a Triathlon

By Shaun Wadham –Level 1 Triathlon Coach

Running well off the bike in a triathlon is a difficult thing to do and is definitely the most challenging part of triathlon, especially for beginners but with training, practice and correct riding technique you can master the run in a triathlon.  

There are a few reasons why your legs feel like rubber and you find it hard to run when you hop off your bike and start the run leg.  The first is lingering muscle cell fatigue caused by overly hard paces.  The second is reduced leg muscle power caused by glycogen depletion.  This is more likely in longer events or when you don’t replace lost carbohydrates during an event lasting longer than about 90 minutes.

The third is the discomfort caused by what is termed, “blood shunting”.  In our running off the bike scenario, blood needs to be redistributed or shunted from the muscles we used for cycling to the muscles required for running.  Although running and cycling both use similar muscle groups, running requires additional muscles to propel us along and to stabilize us.  If we run too hard before the blood has been distributed to our running muscles, excessive lactic acid will be produced, causing us great displeasure and pain.  We will then be forced to slow down and allow the body to clear the build up of lactic acid.

Finally, the nervous system may take some time to adjust to the changing demands placed upon it from the ride to the run, which may decrease the pace you can run at.  This is more likely to occur if your cycling cadence (leg spinning speed) is less than optimal.

So now we know why we feel like rubber man/woman when we get off the bike, how do we become better triathlon runners?


By far the most important factor in being a better triathlon runner is your fitness level.  No race strategy is going to help you if you have not done the work in training.  If you are training to do a triathlon, you need to be doing about 2 runs, 2 rides and 2 swims as a minimum per week to see improvements in all three disciplines.  The American College of Sports Medicine, which is a reliable authority in regards to exercise and health, now recommends 6 sessions per week for general fitness or weight loss, so the frequency guidelines I have just stated are not extreme.  Quite simply you need to make fitness a part of your daily routine.

Keep in mind that to run well in a triathlon you need to be both running and cycling fit. If you haven’t done the work on the bike in training, come race day, your legs will be fatigued going into the run and this will lead to less than optimal running performances regardless of how much running fitness you have built up.

Do Brick Sessions Regularly

A brick session is a training session where you do a run immediately following a ride.  Regular brick sessions (1-2 per week) help you to become used to the discomfort you will feel when making the transition from riding to running in a race.  One positive thing you will discover doing a brick session is that the rubbery legs feeling only lasts for about a kilometre until the blood is redistributed to running muscles.

This type of training is definitely difficult when you first start training and the length of the runs should be short to begin with. This is because you are fatigued when you start running and the possibility of injury is greater than if you were running fresh.  If you have never done a brick session start with a 5-6 minute run off the bike and increase the distance gradually up towards target race distance.

Ride with a Fast Cadence during Training & Racing

During a study on the effect of cycling cadence on running performance in a triathlon, it was found that athletes with a faster cadence (approx. 109 revolutions per minute) significantly improved average running performance at race pace effort over both normal (90 RPM) and slow cadence (71 RPM) conditions.

The biggest factor in the improved performance of the athletes was running stride frequency.  They found that the duration of time which a foot was in contact with the ground was significantly shorter throughout the runs for the fast cadence cycling conditions, which indicated the leg turnover (stride frequency) on the run was greater.

It was suggested that the possible reason for the improvement was because the firing rate of the nervous system during the run is influenced by the firing rate of the nervous system during the ride. Therefore maintaining a cadence on the bike that replicates the optimal firing rate during the run is important if you want to have a good run.

So what is the optimal cycling cadence during a triathlon?  Most experts recommend a cadence of around 90-100RPM for optimal cycling performance. This will most likely drop if you are climbing hills but you should try to keep your cadence greater than 80 RPM during your climbs.  The above study indicates 109 RPM is the optimal cadence if you want to run your best off the bike so I recommend that during a race you keep your cadence at between 90-100RPM for the majority of the ride and then over the closing stages increase it to 105+RPM, which will help you settle into a faster running pace once you hop off the bike.

If you are a beginner, at first you may find it hard to achieve the optimal cadences I have listed above in training and racing but this will not always be the case. Get a cadence counter fitted to your bike to monitor how fast you are spinning your legs when you are riding and include some high cadence efforts in your cycling sessions (10 x 45 seconds of cycling at 100+ RPM) to improve your leg turnover speed.

Negative Split during the Bike and Run Legs

Negative splitting means doing the second half of the ride or run faster than the first half. Scientific research has revealed better performances and personal best times are more likely when races are split negatively (except for short races like a sprint race where its actually better to just go hard and hang on!). Negative splitting is something which takes a bit of practice and discipline.  I generally include this type of training at cycling and running sessions as the season draws closer.  Negative splitting also requires knowledge of what race times you are capable of so it becomes a more effective tool as you gain racing experience.

As part of negative splitting, ensure that you start the ride and run legs at moderate paces to give the body a chance to shunt blood to the working muscle and then quickly move up to your target race pace.


So to improve your running off the bike do the following:

  • Train regularly to improve your aerobic fitness.
  • Do regular ride/run (brick) sessions, starting off with a 5-6 minute run and building up from there.
  • Ride with a cadence of 90-100rpm and increase this to 105+ over the concluding stages of the bike leg.
  • Use a negative splitting strategy in races to ensure you don’t go out too hard early and blow out in the later stages of the bike and run legs.