APRIL 13TH, 2021 BY HEALTHNETWORK

Spring has arrived! And while the weather is in flux in many parts of the country, in some places it can feel downright balmy. As the temperature creeps ever upward, you might be tempted to go for a swim.

One sunny day doesn’t justify a jump in the lake, though. 

The water temperature probably won’t match the warmth of the surrounding air. And swimming in frigid water can be downright dangerous, not to mention unpleasant.

For safety’s sake, most swimmers should wait until the water temperature reaches at least 70 degrees Fahrenheit. But even that can be too chilly for most people to enjoy the experience. 

If you give the water time to warm up, you’ll stay safer and have more fun. Hold off on that day trip to the beach, friend. 

Here’s why warmer water can make all the difference for smart swimming, no matter the time of year.

Cold water is a shock to your system.

Plunging into icy water can do a number on your body. Your system isn’t designed to handle such sudden changes in temperature.

It’s natural to draw a sharp, deep breath when the cold hits your skin. If you’re underwater, you could end up gulping a mouthful of water. This is a drowning hazard.

Your heart rate and blood pressure may skyrocket, too. That’s because cold water causes your blood vessels to contract. This can be troublesome for anyone, but for people with heart problems, it could be deadly.

And you don’t have to participate in any polar plunges to suffer from shock, either. Cold shock can happen at any water temperature below 70 degrees. But the risk becomes particularly high once the temperature falls below 64 degrees.

It’s also harder to breathe.

Even if you manage to avoid swallowing a mouthful of water when you first jump in, swimming in cold water can still affect your breathing.

The cold can raise your respiratory rate, and you might hyperventilate. If you have to come up for air once every second, you’ll have a hard time making any progress through the water.

And even if you can get your hyperventilation under control, you might still need to take breaths more often than normal. Cold water reduces your ability to hold your breath for long stretches.

Your brain may play tricks on you, too. When swimming in icy water, it’s common to feel like you can’t get enough air. If you start to panic, it will be harder to make rational choices about water safety.

Cold water can also keep your arms and legs from working.

Your core contains organs that are vital for life. Because of this, your body will prioritize keeping those organs warm by increasing blood flow to that area. And to make that happen, the blood supply to your arms and legs will be reduced.

As you might suspect, your arms and legs need sufficient blood flow to do their jobs. If they don’t get enough blood, your strokes will slow down. 

Eventually, your movement might be reduced to the point that you can’t keep yourself afloat.

And it may lead to hypothermia.

You’re probably familiar with the idea of getting hypothermia when outside in icy winter temperatures. Cold water can have the same effect, but the temperature doesn’t have to be nearly as low.

Hypothermia happens when the body temperature falls to 95 degrees Fahrenheit or below. The longer you swim in cold water — especially water that’s approaching 40 degrees or lower — the more at risk of hypothermia you’ll be.

This drop in body temperature can cause you to feel very sleepy. You may also struggle to think clearly. Eventually, you could lose consciousness. 

Hypothermia can also cause your heart or your respiratory system to fail.

Plus, your problems may not end once you’re out of the water.

The dangers of chilly swimming don’t end after you get out of the water. Several minutes later, you could be hit with a problem called after-drop. That’s when your core temperature continues to plummet for a bit even though you’re on dry land.

Starting to shiver shortly after exiting the water can be a sign that this is happening. After-drop can cause hypothermia, and it may leave you feeling confused or dizzy.

While you might be tempted to fight after-drop with a hot shower, it’s not a good idea. The extreme switch could actually cause you to faint. Wait until your temperature has stabilized before exposing yourself to a steamy shower.

Planning on swimming in the cold anyway? Prep accordingly.

Although you should always be cautious about swimming in cold water, there are steps that can make the experience safer. (This isn’t meant as medical advice but for information only. Talk to a doctor if you have concerns about your health.)

• First, go slowly. Get in little by little so your body can adjust. Don’t put your face under the water until you can regulate your breathing.

• Also, wear the right gear. That includes a wetsuit, a swim cap and other protective items. These will provide insulation for your body.

• Pay attention to how you’re doing at all times. If you notice that your breathing or heart rate is changing, head to the shore right away. Moving slowly and shivering are additional signs that it’s time to get out.

• After leaving the water, get dry asap. Take off your wet clothes, wrap your body in a blanket, and sip a warm, nonalcoholic drink. Don’t hesitate to seek medical attention if needed.

Always remember that frigid water can be dangerous. Even with these precautions, cold-water swimming poses risks, especially to people without experience.

Don’t forget to check the water temp (not just the air temp), too.

Water and air temperature can differ pretty dramatically. It might be sunny with a high of 75 as you sit on your back deck, but that doesn’t mean your pool is quite as toasty. Check the water temperature before diving in.

Buoyant pool thermometers make it easy to figure out the temperature of swimming pools. 

For open water, such as lakes or the ocean, you’ll probably need to rely on an expert. Consult your local parks department or a weather app for information on current conditions.

Keep in mind that it can take an extended stretch of warm weather before many bodies of water — including unheated swimming pools — will be warm enough for even a short swim. Some beaches are best for building sandcastles all summer long.

And find the right water temperature for you.

No matter where you’re swimming, avoiding water below 70 degrees Fahrenheit is a good rule of thumb for the average swimmer. The truth of the matter, though, is that 70 degrees is still pretty chilly. You’ll probably have a better time if you wait for warmer water.

In fact, you’ll be safer, too. It’s easier to breathe in 77-degree water than in 71-degree water. That’s why pools used for official swimming competitions have to be at least 77 degrees.

It’s common to keep pools for the general public between 83 and 86 degrees. 

Experts recommend a temperature of at least 84 degrees for kids’ swim lessons. Older adults may appreciate warmer water as well.

Just note that anytime you’re in water above 80 degrees, you should focus on staying hydrated, especially if you’re swimming laps.

Temperature guidelines are a little different for water athletes, who may commonly swim in colder water than the general public. With repeated exposure and protective gear, it’s possible to get your body used to colder temperatures. Eventually, entering a frigid lake won’t be so hard on your system.

But no matter how much experience you have, it’s always smart to take precautions and treat the water with a healthy dose of fear and respect. Swimming is safer and more fun when you pay attention to water conditions and don’t subject your body to more than it’s prepared to handle.