How fit do you have to be to do a triathlon?
It’s easy to mistakenly assume that triathlon is the pinnacle of endurance fitness, and to do one you need to be super-human as you have to excel in three sports, not just only one. The reality couldn’t be further from the truth, says Philip Hatzis
Triathlon is one of the world’s most inclusive sports, with people of all abilities taking part, but what level of fitness will you need to reach in your training plan to complete one?
In simple terms, you must be able to tick off the duration of exercise involved in each triathlon distance event to complete the race.
Of course, if finishing is your main aim then you don’t need to go fast and you can take it easy with breaks. So anyone can take part in a triathlon, even if you’re not that fit. Training for your first triathlon will inevitably aid fitness too, no matter your level.
How long is a triathlon?
The most accessible and shortest triathlon distance is the supersprint (400m/437yd swim, 10km/6.2mi bike, 2.5km/1.6mi run), although British Triathlon also run shorter Go Tri events, where the fastest athletes finish in around 30 mins.
With moderate training, completing a supersprint tri can easily be achieved, allowing for two assumptions: you can swim and you can ride a bike. A yes to both must be the first step.
The swim of a supersprint is 16 lengths of a 25m (27yd) pool. Reassuringly, there are pool-based triathlons, which mean you can have a break at the end of each length. Remember: you don’t have to swim front crawl in a triathlon and breaststroke is fine.
The bike’s probably the most straightforward discipline to tick off. While 10km may sound a long way, many people can cover that distance in a short space of time on their old mountain bike. A flat course also makes it easier.
The run’s often of greatest trepidation, being the final discipline. However, most of us have some jogging experience, ensuring the majority can run non-stop for 20-30 mins – aka the distance of a supersprint tri.
Using the 20-30min rule is a useful guide: can you swim, bike or run for 20-30min? If you can in each of the disciplines, you’re arguably in good enough shape to give a triathlon a go. If not, focus on getting to this level first before taking on a triathlon.
Then, it’s simply a matter of completing a few weeks of training and acclimatising to the idea that you must run off the bike.
After supersprint, a sprint triathlon is more or less twice the distance, covering 750m swim (820 yds), followed by 20km bike (12.4 miles) and 5km run (3.1 miles). Then, an Olympic-distance triathlon is double this again, during which you can normally expect to be competing for up to 3h.
Training for your first triathlon
To train for your first triathlon, such as a supersprint, do two sessions of each discipline per week and take one rest day. Each of these sessions should last 20-30mins and you may go longer at the weekend. You could even try and bike in the morning and complete a run in the afternoon.
About two weeks before your race, try a 15-20min bike with a 5-10min run straight after. See how that feels. You’re taking steps to become a triathlete.
Download our free eight-week supersprint triathlon training plan or check out one of our other triathlon training plans for beginners if we’ve convinced you to take the plunge.
How fit do you have to be for longer-distance triathlons?
As you climb further up the triathlon tree, your training will become more focussed. The crucial part of all of this is to build your confidence to know you can get around the course.
For many, that will be completing the distance of each event. Here are a few guidelines to conquer your chosen race distance…
How fit do you have to be to do a sprint-distance triathlon?
You should be comfortable training up to 75% of standard-distance triathlon in each of the disciplines. As standard-distance is a 1.5km/0.9mi swim, 40km/24.85mi bike and 10km run/6.2mi, sprint distance comprises of: 1.125km/0.7mi swim, 30km/18.6mi bike and 7.5km/4.7mi run.
If you can complete these distances individually, you’ll certainly have the fitness to put it all together in an event.
How fit do you have to be to do standard and middle-distance triathlons?
These distances can be trained for by following a good club programme – two swim sessions, two to three run sessions (one interval) and two to three bike sessions.
A weekend ride of 2-3h is plenty to get you around a standard-distance ride and would just about get you around a 90km/56mi route (middle-distance bike).
Training in a club environment, if you can, will provide you with the required fitness to complete a middle distance or standard distance event.
The swims of standard and middle distances are essentially the same length, but the bike and the runs are more than double. If you can ride for 40km/25mi in a standard-distance triathlon, with some regular longer rides of 3h, you’ll build your cycling legs to ride 90km comfortably.
It’s the same story with the run: if you can do an hour of intervals with the club on a Tuesday night, you can probably do a longer steady half marathon run of 21.1km/13.1mi.
For more guidance, check out our free Olympic-distance triathlon training plans, our free 8-week 70.3 training plan and our free 6-month Ironman 70.3 training plan.
How fit do you have to be to do an Ironman triathlon?
Ironman is its own beast. Due to the longer distances, it requires a dedicated training plan, and there’s certainly a shift from a club or hobby environment to a more structured training plan. Time will be your biggest obstacle.
Do you have enough time to do regular 4-7h bike rides? Ironman swim training is longer, but if you have regular club or 1h swim sessions through the week, the swim should take care of itself with a couple of longer swims in the lead-up to the race.
The run can be approached very differently if you’re planning to just reach the finish line. Focus on being able to ride effectively and then schedule an effective run-walk routine.
For long-course training, there becomes a point through the programme where you realise your typical sessions become half-distance (e.g. your steady run becomes 18-25km). At that point, I believe you’re ready to do an Ironman.
For more guidance, check out our free Ironman training plans from 3 to 12 months.
How do I know if I’m ready for a triathlon?
Once you get a good grasp on how fit you have to be to do the triathlon distance that you’re aiming for, you should start training with as much time as possible ahead of your race. The slower the build, the less chance you’ll suffer from injury. Especially if you follow a coach-built expert training plan like those we share for free at 220.
Increase your training and distance slowly and while doing so, start to amass the kit needed to take part in a triathlon, notably a tri-suit, triathlon wetsuit, and running shoes. Once you have the right kit, you can start practicing triathlon transitions and laying your kit out in the right order for use. You should aim not to lose too much time in transition, while being careful not to over-exert yourself before racing back out on the the course once more.
Now you’ve got the basics down, you are ready for your first triathlon. The best way to get into tri is by doing, so sign yourself up for your local race and don’t stress the small stuff if race day doesn’t go perfectly – it’s practice under the belt and a good day out for all involved!
The bottom line
So how fit do you need to be to become a triathlete? The reality is if you can swim, bike and run, you probably have the fitness already to sign up and complete one, just be realistic about deciding the distance for you and work up through the different levels slowly.
You’ll find yourself in an inclusive and exciting group of people. Going for the longer distances may require more specific training, or joining a triathlon club, but that’s also a way to meet new like-minded people and enjoy some great tips on training, kit and routes.
As you increase the distances, available time to train becomes a more significant limitation on your performance. Still, you’ll notice that the consistency of training is crucial in improving your fitness safely.
If you want to be competitive or you come from a competitive sporting background, you may wish to follow a more structured triathlon training plan or work with a triathlon coach.
Both will offer a shortcut to success, but then we start comparing the differences between competing or competing in a triathlon. That is for another time.
Whatever you decide to do, we urge you to take the plunge and join the triathlon community: you’ll love it!
Philip Hatzis
Triathlon and ultra running coach 
