For many swimmers around the world, lakes are the most accessible place to train. The water is often calm, predictable, and perfect for building endurance and confidence in open water.

But when race day arrives, and the swim takes place in the ocean, things can suddenly feel very different.

Salt water, currents, waves, and navigation can all introduce new challenges that lake swimmers may not experience regularly. The good news is that the fundamentals of swimming don’t change, but understanding a few key differences can make the transition from lake to ocean much smoother.

You float a little higher

One of the first things swimmers notice when moving from freshwater to saltwater is buoyancy.

Saltwater is denser than freshwater, which means your body naturally floats slightly higher in the water. For many swimmers, this can actually be a positive, helping keep the hips and legs closer to the surface.

However, it can feel unusual at first if you’re used to lake swimming. Your stroke might feel slightly different for the first few minutes as you adjust to your body position in the water.

The good news is that once you settle in, most swimmers find saltwater swimming feels just a little easier.

The taste of the water

Another obvious difference is the taste.

If you accidentally swallow some ocean water, you’ll quickly understand why people talk about the ‘saltwater experience.’ Even small amounts can leave your mouth feeling dry, sticky, and unpleasant for a while afterwards.

For swimmers who mostly train in lakes, this can be one of the biggest adjustments. The salty taste can linger, and sometimes plain water doesn’t immediately wash it away.

The easiest solution is simply drinking a little more frequently after the swim to help rinse away the salt.

The water is moving

Perhaps the biggest difference between lakes and oceans is that the ocean is rarely still.

Lakes are often calm and predictable, while the ocean can introduce currents, chop, and waves. This means swimmers need to be more aware of how the water is moving around them.

Currents can push you off course, waves can affect your rhythm, and chop can make breathing and sighting a little more challenging.

Because of this, ocean swimmers usually need to adapt their navigation throughout the swim rather than simply following a straight line.

Sighting becomes more important

In calm lake conditions, swimmers might sight every ten to twelve strokes and stay comfortably on course.

In the ocean, that often isn’t enough.

Waves and currents can gradually push you off your intended line without you noticing straight away. Many experienced ocean swimmers sight more frequently, sometimes every three to four strokes, when conditions are rough.

Frequent sighting helps you stay on track and prevents small navigation errors from turning into large detours.

Expect the unexpected

One of the biggest differences between lake and ocean swimming is simply the variability of conditions.

Lake swims tend to be relatively consistent from day to day. The ocean, however, can change quickly depending on tides, wind, and swell.

One day, it might be calm and glassy. The next day, there might be chop, waves, or a strong current.

This unpredictability is part of what makes ocean swimming exciting, but it also means swimmers need to be comfortable adapting as conditions change.

Experience is the best preparation

While there are clear differences between lake and ocean swimming, the best way to become comfortable in saltwater is simply spending time swimming in it.

It might sound cliché, but the more you swim in the ocean, the more natural it becomes. You learn how to handle waves, how to adjust your line in currents, and how to stay relaxed when conditions aren’t perfect.

If you mostly train in lakes but have ocean races on the calendar, try to get into the sea whenever possible before the event. Even a few ocean swims can make a big difference.

Because at the end of the day, swimming in the ocean isn’t about fighting the water. It’s about learning how to work with it.