Which Is Harder – Triathlon Or Marathon?

When it comes to different events and competitions, there is no denying that a triathlon and a marathon are both very difficult.

Even if you have trained appropriately for these events, they are taxing on the body. Given this, it is often difficult to know what is harder, a triathlon and a marathon. While they both feature running, they are very different events. As a result it is not easy to compare the two. 

While many people have different opinions on this subject, in this article, we get to the bottom of this question, to let you know which is the harder competition of the two.

Which is harder triathlon or marathon?

What Is a Triathlon?

A triathlon, as its name suggests, is an event made up of three different sports - swimming, cycling, and then running. The length of each part of the triathlon will vary depending on the type of triathlon a person is competing in.

There are four different types of triathlon that you can compete in -  full, half, Olympic, and sprint. The sprint is the shortest triathlon, and the full triathlon is the longest.

As the distance varies quite significantly, a sprint triathlon is far easier to complete in comparison to a full triathlon. When looking at the full triathlon, the swimming distance is 2.4 miles, the bike distance is 112 miles and running distance is 26.2 miles. In contrast, a sprint triathlon is generally 750 meters for swimming, 12.5 miles of cycling and a 3.1 mile run. As you can see, this is significantly less overall. 

What Is a Marathon?

A marathon is a long distance running event. It spans over 26.2 miles. It is a challenging endurance event that is not easy to complete, and requires a lot of steady, consistent training.

Which is harder triathlon or a marathon? When it comes to comparing both of these events, you may assume that a triathlon is harder. However, this is not necessarily true. It all depends on the type of triathlon you have completed.

While the sprint triathlon consists of three different events, it is a far shorter event in comparison to a marathon. In total, it is close to 16 miles. Given that a marathon is 26.2 miles, it is the longer event.

While you will still need to train for three different events, the training for a sprint tri is far less intense than a marathon. 

With a shorter triathlon, you are focusing on different areas of the body for each event, whereas the marathon is focusing solely on running, which is going to be more taxing on the body over a longer period of time.

However, if you are looking at the full 140.6 miles triathlon, then there is no competition, and this is the far harder event. When looking at the running distance alone for a full triathlon, this is 26.2 miles, which is the same length as a marathon. 

Then in addition to this, there are 112 miles of cycling, and 2.4 miles of swimming. This is very difficult, and when you take into consideration that it involves a marathon within the event it is the more difficult option.

On the whole, when looking at long distance running, this is harder than performing multiple events. This is because it is all one event, and you need to run continuously.

This is taxing on the body both mentally and physically. Long distance running is tougher on your body than cycling or swimming. Given this, a 26.2 mile marathon would be more difficult than the same distance of cycling.

With this in mind, if you are looking at an Olympic triathlon, or a half triathlon, the marathon would be the more difficult event. It typically has a longer recovery time, and it is tough on the body, even for those that have trained.

In terms of training, in some ways training for a triathlon is more difficult than a marathon. This is because there are three different events that you need to think about and for which you must train.

While you do not need to be the best in all three, you need to be good enough at all of these events if you want a competitive time. This makes the training process more difficult as you will need to split up your time between the three events.

This is not to say that marathon training is easy. This is still very difficult. As it is only focusing on one event, in some ways this can be more difficult as you need to perfect just the one event.

The majority of athletes that just compete in a marathon are likely to be far better at the running event than the triathletes, as they are not dividing their time between three events.

Both events require a lot of training. But, when it comes to a marathon, this will always be 26.2 miles. They are never shorter or longer. Given this, there is a certain expectation that needs to be met. However, triathlons are very significant in their length. 


To conclude, the answer of which is harder is not an easy one. Overall it does depend on the length of the triathlon.

If you are taking part in a full triathlon, considering that this involves a full marathon after swimming and cycling, this is clearly the harder event. It is very taxing on the body, and would require a lot of training.

However, the Olympic and sprint triathlons are typically not harder than a marathon. This is because there are three different events, and the body is using different muscles throughout.

Whereas, with a marathon, the athlete is only focusing on intensive running for a long distance, which is more taxing on the body as a whole.

Given this, while you do need to have a wider training program for a triathlon, unless it is a full triathlon, the majority of experts agree that a marathon is the harder event on the whole.