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Why do Triathlons start with swimming?

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A triathlon consists of cycling, swimming, and running. 

These activities can happen in a variety of places and may take place for any number of miles.

This is an Olympic sport which first started in 1920. Triathlons have since become wildly popular across the world today.

Triathlons start with the swimming portion of the race because water is the greater obstacle to an athlete when compared to cycling and running.

It is also the most dangerous leg of the race and performing this leg first reduces the risk of drowning due to fatigue.

For most people and proven in many experiments, swimming is said to be the most difficult physical sport, especially in an overall event as strenuous and hardworking as this one!

Swimming first gets the hard work out of the way, making it easier to do the running and cycling next.

The general school of thought is that if swimming was last in the race, the racer could become exhausted and risk potential drowning.

triathlon swim

Things you need to know for the swimming leg of your triathlon

When considering doing a triathlon, it is important to know that you are up for the challenge and ready to work hard and do your best.

Here is a list of things you should know when considering doing a triathlon and more importantly the swimming portion of a triathlon, known to be the harder part of the race for most:

  • Practice swimming in both deep and shallow water will help build endurance making it easier when the race comes along
  • It is important to be mentally prepared, this can be done by asking yourself if this is something you can achieve both physically and mentally
  • Do workouts daily to 3 times a week to build muscle and endurance
  • It is vital to get the right gear, for example, goggles, swim caps, etc. This all depends on preference and will help you if practiced with.
  • Strive to find different ways to swim at a pace that allows you to finish in time and win that race!

Physical Effects of a Triathlon

Doing a triathlon can be very rewarding both mentally physically and emotionally.

One great factor is the ability they have to allow a great workout for the whole body.

This is a list of the different activities within the triathlon and what part of the body they work out!


Swimming is very good for your health both mentally and physically.

Swimming often and especially during a triathlon will work various parts of the body including your legs, upper body, and core.

This is due to the strenuous work that is done by the entire body. Movements such as the flutter kick helps to engage the core, making it strong.

triathlon cycling run


Cycling is also known as using a bicycle. It is a very good workout for the entire body as well.

It works out mainly the lower body to include the hamstrings, glutes, and quads.

This is also beneficial with the cardiovascular system as this intense workout provides working out of the heart muscle.


Running is primarily done working the full body and mainly the lower body as it is the legs doing most of the work.

These muscles include the glutes, quads, hamstrings, and calves. You will begin to feel a burn after quite a while of doing this.

Important note

If you are someone who has a hard time wading in the water this may be an important factor to consider before entering a triathlon.

These races are very work-intensive and require a great deal of physical health and stamina.

If one is not completely prepared it can cause health risks and potential illness due to the overworking of the body. Be careful and stay safe!

Most common types of triathlons

The sprint

  • Swim – 750 meters(0.45 miles)
  • Bike – 20k (12.4 miles)
  • Run – 5k (3.1 miles)

The sprint triathlon,the most common kind originated in 1974.

This was designed to cater to those athletes who were highly invested in running and wanted to do it at a higher level after doing the other aspects of a triathlon.

It is usually the kind of triathlon that people try first because of the lower distance in each event. (source)

triathletes swimming

The Olympic Triathlon

  • Swim – 1.5k (0.93 miles)
  • Bike – 40k (24.8 miles)
  • Run – 10k (6.2 miles)

The Olympic triathlon originated in 1974.

The main difference in this triathlon is the distance. It is doubled compared to the sprint triathlon.

Essentially the overall time taken for the Olympic triathlon varies per person and the sport.

Overall the swim may take about 15-30 minutes. The cycling takes roughly 1-2 hours and the run takes 40-80 min. (source) (source)

Half Triathlon

  • Swim – 1.9km (1.2 miles)
  • Bike – 90km (56 miles)
  • Run – 21.1km (13.1 miles)

The half triathlon, referring to the total distance that is done, “70.3” (113.0km). This means that all activities are half the distance of other races, including the ironman triathlon.

This triathlon is commonly good for people who are comfortable with the high amount of physical need but are not ready to commit to a full triathlon yet.

They are highly athletic with much training but are starting slowly to maximize agility and endurance. (source)

Reverse Triathlon

  • Swim – 200 meters
  • Bike – 13.1 miles
  • Run – 5k

The reverse triathlon, as the name, suggests is a regular triathlon but in reverse order, the only triathlon known to do this.

Instead of swimming, cycling, and then running. However, the reverse triathlon starts with running, then cycling, and lastly swimming. The run being 5k.

Cycling being 13.1 miles and swimming being 200 meters. This triathlon may take about the same amount of time as the Olympic triathlon but more or less depending on one’s perseverance, determination, and stamina.

These reverse marathons are taken by people who are heavily into swimming and enjoy it more than the other activities, either is fine but it always depends on the person! (source)

Fun fact

These triathlons are commonly done with the swimming portion being in a swimming pool.

It is easier to control mishaps in a pool because since the swim is last and the athletes will be very fatigued.

This may also be done in some other types of triathlons if the water is too cold in certain locations.

triathlon running start before swimming

Ironman Triathlon

  • Swim – 3.9k (2.4 miles)
  • Bike – 3.9k (112 miles)
  • Run – 42.2k (26.2 miles)

The Ironman triathlon, originated in 1975. It orginally started in San Diego but there are now held in several countries and places across the globe.

The name originates from a  pair of men in a cycling club who were very competitive and did a long race, saying whoever finishes first would be called the “iron man.”

This name was then extended to the swimming and running portions.

This race is done by those with very high athletic ability who enjoy high endurance and speed.

It is attempted by over 96,000 people annually. It takes around 17 hours to complete, depending on person and stamina. (source)


Considering the act of doing a Triathalon is a big decision both for mental and physical health.

However, when preparing, it is important that your motivation stays high and that you are aware of the many health benefits of doing a triathlon.

In general, these include:

  • Potential weight loss due to the high activity level
  • Cardio endurance and stamina boost
  • Inspires others to strive for their physical goals
  • Inspires disciplinary skills of working hard and setting goals
  • Less chance of injury as it works the entire body instead of just one part