Can You Get Sick From Swimming In Cold Water? The Answer May Surprise You!

The short answer is no. No, you can not just get sick from swimming in cold water. Exposure to viruses ie. other sick people (or swimmers in this case) is what causes us to get sick. Although, there are negative (as well as positive) side effects from cold water swimming such as hypothermia, none are the direct cause of us becoming sick.

penguins swimming in cold water arctic can make you sick?
Cold swimming does come with multiple risks (not just for humans)

To help ease your mind, this article will further explore cold water swimming based on three variables that apply to every swimmer but first…

How Cold Is Too Cold?

Before we delve into variables, the first question we must answer is: how cold is too cold? To help answer this, here are some numbers for you to become familiar with:

Body Tempurature Scale of Hot to Cold
If your body is submerged in water and not continuously swimming, temperatures below 77F (25C) start to get dangerous.
  • 98.6F (37C) Normal body temperature.
  • 95F (35C) Hypothermia starts.
  • 85F (29.4C) Public pool temperature.
  • 77-82F (25-28C) Olympic competition pool temperature.
  • 70F or below (21C) Water feels cold, proceed with caution.
  • 40F (4.4C) or lower Water is painfully cold.

Since we’re swimming in cold water, the rule of thumb is that any temperature below 77F (25C) starts to become dangerous. If you’re just playing around in the water then 85F (29.4C) is nice and cool for you. If you’re lap swimming, 77-82F (25-28C) is ideal for you and if the water reaches 77F (28C) or lower (usually in an outdoor setting), then it’s time to take some proper precautions as we will discuss below.

Three Variables Regarding Cold Water Swimming

If I were to assess how risky cold water swimming would be to someone, I would look at three variables:

Adult vs Child: Size Does Matter

child wearing snorkel at more risk to hypothermia versus an adult
Children tend to drop in body temperature way faster than adults which is why cold water swimming may not be suitable for younger swimmers.

The reason this variable is so important is based on one reason alone: children lose body heat faster than adults. Smaller frame, higher metabolism and greater heat production put children at more risk for hypothermia than your average adult. The risk is even higher for babies exposed to cold water as they lose heat nearly four times faster compared to that of an adult.

You’re also probably aware that fat not only floats but keeps you warm. Adults tend to proportionately have more body fat than children which is another reason adults tend to drop in temperature much slower. If you’re getting too fat however, perhaps it’s time to start getting in shape like a competitive swimmer.

Indoor vs Outdoor Swimming: The Lesser of Two Evils

If you’re swimming indoors then you don’t have to worry anymore. 99.99999% of all indoor pools located around the world are controlled environments with temperatures suitable for leisure and competitive swimmers. Yes your local pool may feel a little cold to you but is adequate enough for swimming whether you’re a beginner or pro.

Lady swimming in a lane in an indoor public pool
Indoor pools: controlled environments with adequate swimming temperatures

To help convince you to swim in cold indoor pools, I like to compare it to running. Would you rather run outside for an hour on a chilly cold morning or blistering hot afternoon? In other words, the colder the water, the better the swim.

The real problem begins when you start to swim outdoors ie. lakes and oceans. Outdoor water temperatures fluctuate wildly depending on the season, the time of day, heck even from one area of water to the other. If you choose to swim outdoors don’t be surprised if hypothermia starts to kick in. There are however, ways around this based on what you choose to wear.

Well vs Ill-Equipped: Prepare Ahead

Catching hypothermia is as simple as not dressing appropriately for the occasion. If you’re swimming outdoors then wearing a wetsuit is a must. A wetsuit clings tightly to your body keeping you well insulated to withstand the coldest of waters. This is the reason why open water swimmers wear them not just for warmth, but also to improve their buoyancy and performance in fluctuating temperatures.

3877b097456da2a15a9ac574f3d912ba
Wetsuits: a must have item for cold water swimming

If you choose to go in the complete opposite direction and forego wearing a wetsuit, know that you can’t swim for long periods of time. Swimming in open water in harsh conditions ie. wintertime such as polar bear swim are not long term solutions:

Polar Bear Swim Vancouver Bc Aerial Footage 2016 Winner HD

Risks Of Swimming In Cold Open Water

If you do choose to swim outdoors in harsh weather with or without proper gear, know that there are several consequences:

Hypothermia: A Slow Death

Hypothermia is a drop in normal body temperature (36.5-37.5C) when your body begins to lose heat faster than it can be produced. Although a wetsuit may keep your body warm in open water, your head, hands and feet are not and may be at risk.

hypothermia chart
Symptoms of hypothermia are not to be taken lightly

There are various symptoms of hypothermia including:

  • Shivering
  • Cold pale skin
  • Blue lips
  • Tiredness
  • Confusion
  • Fast breathing
  • Slurred speech

Treating hypothermia is quite simple. You, first of all, have to warm up, pull off your wet suit or swimwear, get dried and be covered in blankets. You can have hot tea to warm you up or eat something sugary. It should be noted that the human body takes double the time to warm back up as it takes in order to cool down.

Cold Water Shock: Instant Regret

The main reason why people get into trouble and drown in the cold. The popular belief is that hypothermia causes drowning, but hypothermia slowly sets in after being immersed In cold water for approximately thirty or more minutes.

Cold water shock on the other hand is your body’s involuntarily response to being in cold water. Symptoms can include:

  • Muscle spasms
  • Hyperventilation
  • Increase in blood pressure
  • Increase in pulse
  • Cardiac arrest
  • Involuntary gasp reflex (swallowing water)
  • Muscle paralyzation

Entering the water slowly and floating along the water’s surface is the best way to transition your body into such extreme temperatures. Never jump or dive into the water, please watch the video below for more info:

Cold Water Shock and how to survive it.

Cold Incapacitation: Swimming Paralyzed

The next ten minutes after experiencing cold water shock is highly crucial. If you swim in the cold and are not experiencing a rise in body temperature, then cold incapacitation may occur. Experienced swimmers without enough outdoor swimming experience are susceptible to this.

cold shock
Cold water can be exhilarating and paralyzing

Cold incapacitation occurs when your body repeatedly loses heat and blood is diverted to the core to keep body organs warm. This, in turn, results in the body to simply shut down. The strongest swimmer becomes physically helpless in cold water because they can no longer control their arms and legs and start to drown.

My only recommendation here is to know your limits. Wear a wetsuit and slowly introduce your body to cold water swimming by swimming in shorter sets with a partner or lifeguard watching your back.

Cold Chilblains: A Painful Side Effect

Chilblains are a painful result of repeated cold air exposure. These cold hives or red welts form on the skin (fingers and toes) as seen below.

chilblain hands
Chilblains: no laughing matter

Chilblains don’t usually result in permanent injury, though they are usually itchy, swollen and extremely uncomfortable. The only remedy is to stay in warm for it to clear in one to three weeks. The best approach to chilblains is to avoid developing them in the first place is by limiting your exposure to the cold, dressing warmly and covering exposed skin.

Benefits of Swimming in Cold Water

Now that we’ve gone through the risks of swimming in open cold water, here are some potential benefits:

Boosted Immune System

immune system boost

A broad study of this shows that after experiencing cold water shock, the body’s immune system will kick start itself into producing more antioxidants and white blood cells, in turn, improves the immune system to fight viruses, cold, and even down to heart problems. For beginners, start by switching to cold showers or contrast your hot showers by finishing with a few seconds of cold water.

Improves Your Overall Mood

cold swimmers ice

Endorphins are activated by swimming in cold water much like experiencing a runner’s high. Depression has over time been known to be treated by exercise, and swimming in cold water is a great form of exercise and therapy. Endorphins are released when we are in pain to help us manage the situation and cold water swimming triggers the human pain barrier.

Increased Circulation in the Body

cold water swimmers

Toxins in the veins and arteries of the human body are subsequently flushed out during a cold water swim. It warms our core body organs while pushing blood to the surface. This results in clearer skin, and a healthier glow.

Increase in Libido

canva senior man swimming MACphBl5lbg

With the aim to repress sexual urges, cold water has been found out to naturally carry out that purpose. Oestrogens and testosterone production in the body is increased by cold water swim, with an advantage added to fertility and libido.

Enhanced Loss of Calories

Man doing front crawl in a lake showing bad form in side breath looking behind

In cold water, your heart and body both work extensively harder resulting in higher calorie loss. Several myths may state the opposite but the fact of the matter is: the colder the water, the greater the energy exertion. What is true is that no matter what type of swimmer you are (indoor or outdoor) you will develop an appetite after every session that’s for sure.

Reduction of Stress

wim hof meditating in ice climate surface winter stress reduction cold

Just being in cold water ensures that the body becomes more calm and relaxed due to the decreased body temperature while in the water. These then relieve stress nerves, making the body relaxed or present. Cold water swimming is in someways an exercise in mindful meditation.

Closing Thoughts on Cold Water

Swimming in cold water doesn’t make you sick, viruses do. Yes the body is more susceptible to hypothermia if the water temperature reaches77F (28C) or lower which is usually witnessed firsthand in open water swimming. But with proper gear and precaution, any swimmer can tackle the harshest conditions out there. Share your personal cold water experience with other swimmers and ask for help if ever you get stuck. Good luck!

Frequently Asked Questions

How long is it safe to swim in cold water?

lap swimming in the arctic cold winter with two swimmers swimming in two separate lanes outdoors in ice cold weather

If after stepping into the water and vigorously swimming for approximately ten minutes you still feel extremely cold, then you should exit immediately. Cold water tolerance varies depending on the size of the swimmer (adult vs child), the environment (indoor vs outdoor) and gear (wetsuit or wearing a bare swimsuit).

Can I swim in 70 degree water?

Man doing front crawl in a lake showing bad form in side breath looking behind

According to the World Health Organization, 78-86F water temperature is most suitable for swimming, but a water temperature of below 70F may cause an increase in your heart rate and blood pressure so proceed with caution especially when swimming outdoors without supervision.

Can you get pneumonia from swimming in cold water?

Funny Side Breath

No, you can not. Our parents and grandparents had believed and instilled sayings in us that cold water causes pneumonia. Well, contrary to that, the only things that can be caught while swimming in cold water are viruses and bacteria which comes from other people.

Can cold water shock kill you?

woman swimming barely dressed outdoors in the cold water shock

Cold water shock can be lethal to the body leading to paralysis. The actual shock will not kill you but prolonged cold water exposure can lead to death by hypothermia or drowning.

Should you warm up before swimming in cold water?

Man squatting in shallow water in an indoor public pool

Warming up before swimming in cold water is definitely important, especially for lap swimmers. This reduces the effect of cold water shock by opening up your capillaries to warm up the blood flowing around your body, increasing your heart rate slowly. I recommend warming up by jumping rope (or do jumping jacks) and light stretching before entering the water.

Is it better to swim in cold water or warm water?

female swimmer in an indoor pool underwater performing a flip turn push off the wall which is actually a jump squat exercise

Depends on your purpose for being in the water. For leisure, warm water is good. For lap swimming, cold water is good. Warm water is primarily used by leisure pools such as waterparks and family oriented public pools while cold water is used by universities and olympic facilities for competitive swimming.

Is it safe for swimmers especially children to swim in the winter time?

Child performing an assisted backfloat with swim instructor in indoor pool

Yes! Serious swimmers swim all year round. It’s just that summer season is the most popular time for non swimmers to enter the water. If you are concerned with you (or your child) catching a cold while swimming in the winter note that indoor pools are controlled environments. They raise the pool and air temperature in order to keep their patrons warm and be aware that getting sick can happen all year round based on catching a virus from others.

7 Day Swim