Training for Open Water Swimming Season: Why Winter Is the Perfect Time to Prepare

Paula Veloso
by Paula Veloso
3 months ago

Open water swimming season in Portugal typically starts in June and runs throughout the summer, bringing dozens of races, crossings and triathlon events across the country.

But if you wait until late spring to start preparing, you’re already behind.

Winter is the ideal time to build the fitness, confidence and technique needed to enjoy and perform well in open water swimming races. Whether you’re targeting your first race or aiming to improve performance, what you do now will shape your season.

If you’re planning to join open water swimming events in Portugal this year, here’s how to train smart during the colder months.

Why winter training matters for open water swimmers

Many swimmers reduce training in winter, but those who stay consistent gain a major advantage when race season begins.

Winter is the time to:

  • Build aerobic endurance
  • Improve technique
  • Develop strength and efficiency
  • Prepare mentally for long-distance swimming

When June arrives and open water races begin, your body should already be ready for longer efforts.

Build your endurance in the pool

Even if you can’t swim in open water during winter, the pool is your best ally.

Focus on:

  • Longer aerobic sets
  • Consistent weekly volume
  • Controlled pacing
  • Breathing patterns

Open water races require sustained effort, not sprint speed. Use winter to gradually increase distance and comfort in the water.

Consistency matters more than intensity during this phase.

Improve technique and efficiency

Winter is the perfect moment to refine your stroke without race pressure.

Work on:

  • Body position
  • Breathing rhythm
  • Bilateral breathing
  • Efficient pull and kick

Small technical improvements now can save huge amounts of energy in long-distance open water races.

Consider including drills and, if possible, occasional feedback from a coach or experienced swimmer.

Strength and mobility training

Open water swimming demands more from the body than pool swimming alone.

Adding strength training during winter helps:

  • Prevent injuries
  • Improve stroke power
  • Increase endurance
  • Stabilize shoulders and core

Focus on:

  • Core strength
  • Shoulder stability
  • Back and mobility work

Two short strength sessions per week can make a big difference by summer.

Prepare for cold water gradually

If you plan to compete in sea or lake events, water temperature will be a factor early in the season.

When conditions allow:

  • Start with short exposures
  • Use a wetsuit if needed
  • Focus on breathing control
  • Never swim alone

Cold adaptation takes time and should be gradual. The goal is comfort and safety, not extremes.

Set your open water goals early

Many open water swimming races in Portugal open registrations months in advance. Planning early helps you stay motivated through winter training.

Ask yourself:

  • Is this your first race?
  • Are you aiming for a specific distance?
  • Are you preparing for triathlon?
  • Do you want to improve performance?

Having a clear goal makes winter training purposeful.

Discover open water swimming races in Portugal

Portugal offers a growing calendar of open water swimming events, from short accessible crossings to long endurance challenges.

Exploring races early allows you to:

  • Choose distances that match your level
  • Plan training with purpose
  • Secure your spot before events fill up

Some events now even allow direct booking through RaceFinder, making it easier to discover and join your next challenge.

Start now, enjoy summer races later

Open water season may begin in June, but successful races are built months before.

Train through winter, stay consistent and arrive at the start line confident, prepared and ready to enjoy the experience.

Your summer swimming season starts now.

More from the blog

Musings on swimming, running and riding for everyday athletes.

7 Mistakes Runners Make When Choosing a Race (and How to Avoid Them)
6 May 2026

7 Mistakes Runners Make When Choosing a Race (and How to Avoid Them)

Choosing a race should be exciting. But a lot of runners end up picking the wrong race for the wrong reasons — and only realize it when it’s too late. If you’ve ever signed up for something and thought “why did I choose this?”, this is for you. 1. Choosing a race just because it’s […]

Read More
Portugal Is One of the Best Trail Running Destinations in the World — Here’s Why
5 May 2026

Portugal Is One of the Best Trail Running Destinations in the World — Here’s Why

There’s something trail runners from across the world are discovering: Portugal is a country built for this sport. It’s not a coincidence. It’s geography, climate, and a density of trails that few European countries can match. Within a two-hour drive from Lisbon, you can be in the Serra da Estrela, the Peneda-Gerês National Park, the […]

Read More
Running Calendar in Portugal – May & June 2026: Where to Race Next
4 May 2026

Running Calendar in Portugal – May & June 2026: Where to Race Next

May and June are some of the best months to run in Portugal. Longer days, great weather, and a packed race calendar make it the perfect time to find your next challenge. Whether you’re looking for a road race, your first trail, or a more demanding endurance event, here are some of the best races […]

Read More
From road running to trail running: how to make the transition (and 6 races in Portugal to get started)
30 Apr 2026

From road running to trail running: how to make the transition (and 6 races in Portugal to get started)

If you already run regularly on the road and feel curious about trying trail running, this might be the perfect moment to take that step. The transition doesn’t need to be complicated. Many runners discover that trail running brings new motivation, improves endurance, and makes training more enjoyable and varied. Here are a few practical […]

Read More