Pool vs. Open Water Swimming: How Each Impacts Your Stroke and Why Both Are Important for Triathletes

Swimming is an essential part of triathlon training, but understanding the differences between pool swimming and open water swimming is key to improving your performance. While you race in open water, pool swimming remains an invaluable training tool for building your technique, endurance, and speed. Let’s break down how these environments differ and why both are critical for triathletes.

Key Differences Between Pool and Open Water Swimming

1. Environment and Conditions

   • Pool Swimming: Controlled environment with clear water, lane markers, and a wall for push-offs and rest. It’s predictable and ideal for focusing on technique.

   • Open Water Swimming: Unpredictable conditions, such as waves, currents, and varying visibility. Navigation and adaptability are crucial.

2. Stroke Technique

   • Pool: Precision in stroke mechanics can be honed without external distractions. Swimmers often rely on the black line on the pool floor for alignment.

   • Open Water: Requires adaptations like higher stroke rates to manage choppy water and lifting your head for sighting. Maintaining rhythm in chaotic conditions becomes essential.

3. Breathing

   • Pool: Regular breathing patterns are easier to practice, and you can focus on bilateral breathing.

   • Open Water: Breathing must adjust based on waves, sun and positioning relative to competitors or buoys, often requiring unilateral breathing.

4. Pacing

   • Pool: Lap clocks and marked distances allow for precise pacing and interval training.

   • Open Water: Without lane lines or walls, pacing is more intuitive, relying on perceived effort or GPS devices.

5. Turns and Walls

   • Pool: Frequent turns at the wall provide micro-breaks and momentum from push-offs, which don't exist in open water.

   • Open Water: Continuous swimming requires sustained effort without the help of walls, demanding greater endurance.

Why Pool Swimming Benefits Open Water Performance

Although you’ll race in open water, pool swimming offers several advantages that directly translate to open water success:

1. Focus on Technique
   The controlled setting of a pool allows you to work on the fine details of your stroke—arm positioning, kick efficiency, and body rotation. A strong, efficient stroke developed in the pool helps you maintain energy in open water.

2. Improved Fitness and Speed
   Interval training in a pool lets you push harder in short bursts, improving your speed and anaerobic capacity. This is harder to achieve in open water without structured distance markers.

3. Skill Drills
   Drills like catch-up, sculling, and hypoxic sets are easier to practice in the pool and can directly enhance your open water performance. For example, practicing bilateral breathing in the pool helps you adjust to open water’s dynamic conditions.

4. Confidence Booster
   Consistent pool training builds your fitness, making the transition to open water less daunting. Knowing your stroke is efficient and your fitness is solid gives you the confidence to tackle waves, currents, and competition.

5. Simulation Opportunities
   While nothing replicates open water fully, you can simulate race conditions in a pool by practicing sighting, swimming in crowded lanes, or doing long continuous swims.

Tips for Combining Pool and Open Water Training

1. Blend Both Environments
   Aim for regular pool sessions to refine your stroke and fitness, complemented by open water swims to practice navigation, sighting, and adapting to conditions.

2. Practice Sighting in the Pool
   Add sighting drills to your pool workouts by lifting your head periodically to mimic spotting a buoy.

3. Adapt Your Stroke
   Practice increasing your stroke rate in the pool to prepare for rough open water conditions.

4. Race-Specific Workouts
   Use pool training for speed work and drills, and open water sessions for long endurance swims to build mental and physical resilience.

Conclusion

While the open water is where you’ll race, pool swimming is where you build the foundation of a successful performance. By combining the precision of pool training with the adaptability of open water practice, you’ll become a well-rounded swimmer ready to tackle any triathlon challenge.

No matter where you train, the key is consistency, a focus on form, and a willingness to embrace the unique challenges of both environments. Ready to take your swimming to the next level? Dive in and make the most of every swim session, whether in the pool or the open water!

Julia Aimers
CSEP Clinical Exercise Physiologist
CSEP High-Performance Specialist

Certified Triathlon, Cycling, Yoga and Swimming Coach
USA Cycling Level 2 Coach
Training Peaks Accredited Coach