Is Swimming an Aerobic or Anaerobic Exercise? (Or Both?)


Exercises are grouped in two different categories in general. It can either be aerobic or anaerobic. For those who know what they are, a question can often bubble up in their head, is swimming aerobic or anaerobic?

Swimming can be both an aerobic and an anaerobic exercise. When one swims at a relaxed pace with plenty of time to breathe, it is aerobic. But when the same person swims against the clock and pumps up the heart continuously, it is anaerobic.

What is an Aerobic Exercise?

Aerobic exercises are those in which oxygen is the main fuel and the body can supply demanded oxygen for a longer period of time. Walking, jogging, and cycling are some good examples of it.

Let’s break it down. When you are jogging, the body converts carbohydrates, and fat into fuel with the help of oxygen coming from the breaths. The intensity is so much that the body can keep up with the conversion effortlessly for the first few minutes.

How long it can keep converting depends on how much you have trained your cardiovascular system. This is why the beginners struggle to jog for a stretched period whereas a trained person can jog for hours with no problem.


What is an Anaerobic Exercise?

Anaerobic exercises are those in which glucose is the main fuel and the body starts breaking glucose without oxygen due to the increased demand. Sprinting, weightlifting, and HIIT are some examples of them.

When you are sprinting, the body lacks enough oxygen supplied via breathing. In order to keep you going, it will reserve back to the stored glucose and start producing the fuel through the process of glycolysis. Glycolysis produces amino acids which is why the muscles get exhausted after some time.

Like any other exercise, the efficiency of glycolysis depends on the diet and how you have trained your cardiovascular system.

Aerobic vs. Anaerobic: The Good and The Bad

Aerobic exercises are some of the non-negative exercises on the planet. That means, there are only pros to aerobic exercises, no cons. It helps people lose weight, control blood pressure, increase stamina, and prepare the body to battle against high-intensity workouts.

On the other side, anaerobic exercises are more fitted for intermediate or advanced fitness players. Because it might be a little too much on a beginner’s body which can also cause injuries. However, though, on the bright side, anaerobic exercises are the way to go for building muscle mass, and strength, and burning fat faster.

YouTube video
Video Creator: Dorian Wilson

When is Swimming Aerobic?

Swimming is aerobic when it is performed as a recreational activity. Some people will straight-up say that swimming is aerobic just because the majority of people swim to relax or have fun. You don’t bump the intensity up enough that the body needs to use its stored resources.

A long-distance swim can be aerobic if the pace and the heart rate are consistent over the whole period. It is most effective when you are just going from point A to point B without a clock.

Pool exercises like walking, jumping jacks, and water Zumba are also considered aerobic and are good ways to train the body for a better cardiovascular system.

When is Swimming Anaerobic?

Swimming can always be anaerobic when you turn up the intensity. Doesn’t matter which type of swimming, if the intensity is so much that the breath you are taking in is just not enough to fuel the body, it is anaerobic.

Especially when you are learning how to swim for the first time or training for a competition, the body will fall back on glucose reserve to meet the demand. Swimming is one of those calorie-hungry exercises which can burn up to a thousand calories in an hour.


If you are wondering which types of strokes activate anaerobic respiration quickly, butterflies and fast freestyle are the worthy contenders. Combine them with timed laps and you will see the effects immediately.

Should You Swim Aerobically or Anaerobically?

I believe this is probably the most important question of the whole bunch. And the answer might surprise you a little bit. You should swim aerobically until you are confident enough to do anaerobic.

Aerobic exercise builds the base or you can also call it the foundation exercise. If the foundation is not good enough, whatever you try to pull off will collapse or will show signs of damage.

The same goes for swimming. If you start with anaerobic swimming without a good aerobic base, you will see a nerfed peak in your career and could also end up hurting yourself badly.

YouTube video
Video Creator: Average Running PT