Every swimmer, from the casual lapper to the competitive athlete, eventually asks the same question: how often should I actually be breathing? It’s a fundamental dilemma, pitting the body’s need for oxygen against the desire for a faster, smoother stroke.
The Swimmer’s Central Conflict
At its core, swimming presents a unique challenge not found in most land-based sports. While running or cycling, you can breathe whenever you need to. In the water, every breath is a deliberate act that can disrupt your streamlined position and create drag. Turning your head to inhale, even for a moment, alters your body's alignment and can slow you down. This creates a constant trade-off: getting the oxygen your muscles crave versus maintaining the most efficient form possible through the water. The quest for the 'perfect' breathing pattern is really a search for the sweet spot between these two competing demands, a balance that changes depending on your speed, distance, and individual physiology.
The Real Reason You Need to Breathe
Most people assume the desperate urge to breathe during intense exercise comes from a lack of oxygen. However, the primary driver is actually the build-up of carbon dioxide (CO2) in your blood. As your muscles work, they produce CO2 as a waste product. Specialised receptors in your brainstem are highly sensitive to rising CO2 levels and trigger a powerful reflex to breathe in order to expel it. This is why holding your breath feels so uncomfortable long before you are truly low on oxygen. Understanding this changes the game. Improving your breathing isn't just about inhaling more; it's also about becoming more efficient at exhaling and training your body to better tolerate the presence of CO2.
Bilateral vs. Unilateral Breathing
The most common debate among swimmers is about breathing patterns. Unilateral breathing means breathing to the same side every two strokes. This is often comfortable but can lead to an asymmetrical stroke and muscular imbalances over time, as you consistently rotate your body more to one side. Bilateral breathing, typically done every three strokes, alternates the breathing side. Many coaches champion this method because it promotes a more balanced, symmetrical stroke, helps you swim in a straighter line, and is crucial for open-water swimmers who may need to breathe away from waves. Some research suggests that a three-stroke pattern provides an optimal balance between oxygen intake and stroke efficiency, resulting in faster times and lower perceived effort.
The Misunderstood World of 'Hypoxic' Training
The term 'hypoxic training' is often used to describe sets where swimmers deliberately restrict their breathing, for example, by breathing only every five or seven strokes. The belief was that this trained the body to perform with less oxygen. However, this is a dangerous oversimplification. Forcing long periods of breath-holding, especially after hyperventilating (taking rapid, deep breaths), can significantly increase the risk of shallow water blackout—a sudden loss of consciousness that can be fatal. Modern coaching focuses more on 'breath control' or 'CO2 tolerance training' on dry land and during carefully supervised surface swimming drills. The goal is not to starve the body of oxygen, but to improve comfort with CO2 build-up and maintain technique under fatigue, without the extreme risks associated with underwater breath-holding contests.
Finding Your Personal Rhythm
Ultimately, there is no single breathing pattern that works for everyone in all situations. For beginners, the main goal is to breathe consistently and avoid holding your breath, often starting with a breath every two strokes. For distance swimmers and triathletes, a rhythmic bilateral pattern (every three strokes) is often ideal for maintaining balance and endurance. Sprinters, on the other hand, might take very few breaths during a short, explosive race like a 50m freestyle to minimise drag. The best approach is to become comfortable with several patterns. Work with a coach, listen to your body, and experiment during training to find what feels most sustainable and efficient for the type of swimming you do.
















