Undulating wave breaststroke is the fast competitive variant. How to press the chest and lift the hips – and why you must protect your lower back doing it.
The honest answer to "flat or wave breaststroke?": undulating wave breaststroke is the faster competitive variant – but it's more demanding and loads the lower back significantly more. For relaxed fitness swimming, flat breaststroke is enough; if you want to get faster, you learn the wave deliberately and in measured doses.
The idea behind it: instead of lying flat in the water, you send a body wave from the chest to the hips. As the arms shoot forward you press the chest slightly down, the hips rise, and your body dives slim forward – like a dolphin entering the water. That lowers the drag in the stretch, which dominates the energy cost in water, and helps carry speed across the stroke.
The wave is seasoning, not an end in itself. A small wave driven from the core makes you faster; a big wave torn out of an arched back wrecks your back. This guide shows you the fast version – and how to swim it safely.
### 1. Understand the wave The wave runs front to back: the chest presses down, the hips rise, then the impulse rolls into the legs. It doesn't replace your propulsion from arm and leg – it only makes the stretch slimmer and faster.
### 2. Press the chest As the arms shoot forward, you lean slightly onto the chest, like "downhill". This gentle pressure automatically lifts the hips. Imagine ducking your upper body slightly under an imaginary wave.
### 3. Lift the hips, not the arched back The critical point: the hips rise because the chest presses – not because you bend the lower back. Draw the navel in slightly, gently squeeze the glutes. That way the wave comes from the trunk and not from the lumbar spine.
### 4. Keep the wave small A good competitive wave is surprisingly flat. The bigger you make it, the more up-and-down drag and back load you build. Think "slim dolphin motion", not "hump".
### 5. Dose it over distance On short, fast distances the wave may be a little more pronounced; on long distances you flatten it to spare the back. Ease in slowly and listen to your lower back. Rule of thumb: better a wave too small that your back shrugs off than one too big that you feel the next day.
Straight talk: butterfly and breaststroke are the two most back-intensive strokes – the repeated hyperextension of the wave motion is a known risk factor for lower-back complaints. Build the wave only with a stable core and never overdo it.
If you already have back pain or come from a disc or facet-joint history, you're better off with flat, low-hyperextension breaststroke and should clear the topic with a physio or doctor. A slight pull in the lower back is a stop signal, not a training stimulus.
Practise the wave first without arms and legs: stretch out and send only small, core-driven waves through the body, face in the water. That teaches you the wave comes from chest and belly – not from the lower back.
If the motion feels like a gentle rocking of the chest and not like an arched-back jerk, you're doing it right. Only then do you put it into the full stroke.
### What's the difference between flat and undulating breaststroke? In flat breaststroke you stay horizontal in the water; in undulating wave breaststroke you send a body wave from chest to hips. The wave is faster and more modern, but technically more demanding and more back-intensive. For fitness, flat is enough; for speed, the wave is worth it.
### Is wave breaststroke faster than flat breaststroke? Generally yes – the wave makes the stretch slimmer and helps carry speed across the stroke. That's why almost all competitive swimmers undulate. But the time gain only comes with clean core control; swum sloppily, a big wave tends to brake.
### Is wave breaststroke bad for the back? It can be. Breaststroke and butterfly load the lower back the most through repeated hyperextension. With a stable core and a small, measured wave the risk is manageable. With existing back issues, the flat variant is the smarter choice.
### Which body part does the wave come from? From chest and trunk, not the lumbar spine. You press the chest, a stable belly passes the impulse on, the hips rise as a result. Actively wrenching the hips up via an arched back is doing the wave wrong and risks back complaints.
### Do I have to learn the wave as a recreational swimmer? No. For relaxed, healthy swimming, flat breaststroke is entirely enough and gentler on the joints. The wave is a speed tool for ambitious swimmers with good core strength. Only learn it if you really want to get faster – and then cleanly.
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