Running is an excellent form of exercise and a fun sport to be part of. The running community is supportive, and training for races is motivating and helps you become a better athlete.
For many runners, running is their “home,” so to speak, in the athletics world. They are more than happy with focusing solely on running and training for road or trail races.
However, some runners decide they’d like to dip their toes in the triathlon world—perhaps after an injury or just because a new type of challenge sounds like the most appealing direction.
But how do you transition from running to triathlons? Is it easy for runners to train for a triathlon?
In this article, we will discuss how to transition from running to triathlon in case you want to expand your repertoire and become a multi-sport athlete.
More specifically, we will cover:
- What Is a Triathlon?
- How Long Is a Triathlon?
- 7 Tips for How to Transition From Running to Triathlon
Let’s get started!

What Is a Triathlon?
Most likely, if you’re looking into how to transition from running to triathlon, you have a general understanding of triathlons, but just in case, let’s cover the basics.
A triathlon is a multi-sport event that involves three disciplines performed back to back in a race.
Athletes first swim, then bike, and then run.
How Long Is a Triathlon?
Although there are triathlons that have other distances for each leg of the race, in much the same way that there are standard running race distances—namely 5k, 10k, half marathon, and marathon—so too are there standardized triathlon distances.

Here are the main triathlon race distances:
Super Sprint Triathlon
Swim: 400m
Bike: 10 km (6.2 miles)
Run: 2.5 km (about 1.5 miles)
Sprint Triathlon
Swim: 750m (approximately 0.5 miles)
Bike: 20 km (12.4 miles)
Run: 5 km (3.1 miles)
Olympic Triathlon
Swim: 1500 m (almost 1 mile)
Bike: 40 km (24.8 miles)
Run: 10 km (6.2 miles)

Half Ironman (70.3)
Swim: 1.2 miles
Bike: 56 miles
Run: 13.1 miles (half marathon)
Ironman Triathlon (140.6)
Swim: 2.4 miles
Bike: 112 miles
Run: 26.2 miles (full marathon)
Note that, like running races, in addition to these primary triathlon events, there are any number of random intermediary distances, particularly for smaller, local races.

7 Tips for How to Transition From Running to Triathlon
If you’re a runner who wants to transition from running to triathlon, you’re already well ahead of the crowd in terms of having the fitness and mindset you need to be a good triathlete.
Here are some tips for how runners should go about training for their first triathlon:
#1: Reduce Run Volume
It probably comes as no surprise that if you’re going to start training for three sports instead of just one, you need to cut back on the amount of running you’re doing.
Although this is simple in theory, many runners find it mentally difficult to decrease their training time, especially if they love running.
However, if you truly want to transition from running to triathlon—or even just train for a triathlon as a runner and then go back to just running—you need to spend a decent amount of time training for the swim and bike portions as well.
Unless you have endless free time in the week, you have to be judicious in how you partition your training time, and no matter what your schedule looks like, you also need to partition your energy.
The body can only handle so much training volume, so if you’re running 40-50 miles per week already and hoping to add several hours per week in the pool and quite a number of hours in the saddle, you’re looking at a recipe for overtraining.
High mileage running is also counterproductive to triathlon success because it can decrease the bike’s leg muscle strength and mass and increase the risk of injuries due to the high impact and longer recovery.
We tend to like to work on our strengths, but our dedication to improving our weaknesses can make bigger gains.

#2: Focus On the Bike
As mentioned, runners training for triathlons should cut back on running and instead should focus their efforts and training time on the bike.
When you consider the relative time spent on each discipline in a triathlon event, the bike not only entails the furthest distance by a long shot but also consumes the greatest percentage of time in the race.
For example, in a sprint triathlon, the 750m swim might take 10-12 minutes for the average beginner.
The 20k (12.4-mile) bike might take a little over an hour or 75 minutes, while the 5k run might take 25-30 minutes for a beginner.
This means that the bike portion is at least twice as long as either of the others.
Because the Olympic distance triathlon simply doubles the distance of each leg, the same relative proportions remain. The longer triathlons hold similar skewed equivalencies with each discipline.
Since most of the race time is spent on the bike, most of the training time should be spent on the bike.
One of the benefits of transitioning from running to triathlon is that running has helped you build up your cardiovascular fitness and leg strength, both of which are the bread and butter of cycling needs.
However, the muscular demand for cycling is somewhat different from running, and you really need to spend time on the bike to develop the leg strength you need to dominate the relatively major bike portion in a triathlon.
Runners training for a triathlon should compensate for their relative discipline weakness by aiming for a 1:5 ratio of run-to-bike volume.
For example, if you consider hours of training per week, you might train two hours running and ten hours biking (plus some swimming). Alternatively, with mileage, if you’re training for an Olympic distance triathlon, you might run 12 miles per week and ride 60 miles.

#3: Change From Pace to Heart Rate
Most runners focus primarily on pace as the primary metric to guide intensity.
It’s easy to hone in on your minutes per mile or minutes per kilometer running pace when you’re trying to follow a running workout, but with triathlon, it’s usually more helpful to focus on heart rate zones for intensity or effort level.
This is particularly relevant on the bike because you will be covering way more distance and moving much faster over the varied terrain.
Climbs and descents really affect pace, much more so than running, so heart rate zones and power are often more relevant data to follow.
Use a heart rate monitor with your training and start to familiarize yourself with your heart rate zones.
Even if you end up mostly running before your first triathlon, heart rate training can be a powerful tool for running, too.

#4: Don’t Be Afraid to Get Coaching
Running is a fairly simple sport with relatively little technique, but both swimming and cycling are highly technical, and your technique matters.
Working with a coach, even for a session or two in the pool or on a bike trainer, can help correct some basic form mistakes that can compromise your efficiency and increase the risk of injury.
#5: Fuel Like a Triathlete
Triathlon training burns a tremendous number of calories, so it’s critical to fuel your body before, during, and after your workouts.
Just like your running, you need to create a flawless fueling strategy to help you perform at your very best.
Practice your fueling on the bike, and use brick workouts (bike then run back to back) to experiment with how your stomach handles your bike fuel while on the run.

#6: Rehearse Transitions
Make sure you do brick workouts, which involve running right off a bike workout without a break in between. Also, be sure to practice getting on the bike after you swim.
Not only is it important to rehearse these transitions to nail down the logistics of swapping your gear, but it also helps prepare your body for the feeling of switching activities without a break in between.
#7: Enjoy the Novelty
If you have been running for a long time, you have developed such proficiency that you probably take the challenges of the sport for granted.
One of the joys of starting a new hobby or activity as an adult is that you get to go through the process of learning and improving on a grosser level.
You will make huge strides in your abilities as you start to train in your weaker disciplines, and it’s really gratifying to master new skills, hit fitness milestones, and tackle challenges that intimidate you.
Enjoy the process of becoming a multi-sport athlete; it’s an awesome journey.
If you would some guidance and a training plan to work on the running portion of your triathlon, check out our different training plans and guides to help you along your journey:
