The Power of Bilateral Breathing（双侧换气的威力）
why all swimmers should breathe bilaterally… and why you failed when you tried it before.
What Is Bilateral Breathing? （什么叫双侧换气？）
Bilateral is swimming jargon for breathing to both sides, left and right. Classically this is done every 3 strokes (counting both arms) so your breathing alternates from side to side. But equally it could be done every 5 or even 7 strokes.
Actually anything that involves swapping sides is bilateral. So breathing 2 or 3 times to one side then swapping to the other side is bilateral. Or even breathing a whole length of the pool to the left then swapping to the right side for the next lap.
The only important thing is that you breathe regularly to both sides.
Why is it important to breathe bilaterally?（双侧换气为什么重要？）
Because it’s the natural way to keep your stroke technique symmetrical. Bilateral is particularly good for developing good body roll to both sides since you need to rotate well to breathe.
If you only breathe to one side it’s nearly impossible to maintain a symmetrical stroke. Over weeks and months of swimming your technique gradually become lopsided and crabby. There’s a classic chain of events we see with one-sided breathers:
1. Your rotation on the non-breathing side becomes poor. We very rarely see a one sided breather with good rotation on the opposite side.
2. Poor rotation means your recovering arm will swing low over the water. The swinging momentum of that arm causes it to cross over your centre line.
3. Crossing over at the front of the stroke causes you to snake in the water. This pulls you off course.（身前的划水过中线造成你在水中蛇形，这会拉你偏离航向。）
4. A cross over also tends to cause you to lose balance in the water. This loss of balance often results in a scissor kick.
5. A cross over at the front of the stroke tends to cause your elbow to drop, also damaging your catch and hurting your propulsion.
6. Poor rotation, low swinging arms and cross-overs are the major causes of shoulder injury.
I’ve seen elite swimmers on TV and they don’t always breathe bilaterally?（我曾经在电视里看到高手他们并不总是双侧换气？）
That’s true. Elite swimmers tend to do whatever is natural when racing. So should you – when racing.
When elite swimmers breathe to one side in a race they are often doing so for tactical reasons. To keep an eye on an opponent, or in open water to avoid looking into the sun or waves.
However, they do spend a lot of time in training breathing to both sides. As the weeks and months of training go by, this keeps their strokes symmetrical – and so fast!
Under stressful racing conditions elite swimmers may have a preferred side to breathe and as they swim sub 60 seconds per 100m may need the extra oxygen too. But they are not stuck with single-sided breathing in training as this would cause their stroke to deteriorate.
Our advice: Make sure you’re not either.（我们的建议是：确信你也不是这样的）
OK, Bilateral Helps Keep Me Symmetrical How often do i have to use it?（那好，双侧换气有助于保持我对称，那应该多久使用一次？）
Most of the time. Ideally most of your warm ups/downs, steady swims and technique work will be swam breathing bilaterally.
If you can, also swim your harder quality swims bilaterally. Don’t forget you can breathe a few times to one side before swapping so you are breathing more often. You could use a pattern like 3-2-3-2… the numbers being the number of strokes between breaths.
If you cannot manage bilateral breathing for a whole pace set then start out each repetition bilaterally.
Be as persistent as you can be, your stroke technique will benefit hugely in the long run.
Bilateral Breathing and racing（双侧换气和比赛）
When you are racing, breathe in whatever way feels natural. Because of your training, your stroke symmetry will hold together if you return to a single sided breathing technique during the race.
If you’ve become comfortable breathing to both sides, you can now choose a side to suit the direction of the swell or sun.
Use your breathing skills for tactical reasons in a race, swap sides occasionally to keep a good eye on your competitors and to help with navigation.
Is there a trick to doing it?（做这个是否有窍门？）
Actually, yes there is. But it might not be what you think.（确切地讲，是的，有窍门。但它可能不是你想的那样）
Whenever your face is in the water, exhale constantly and strongly.
If you are struggling with bilateral breathing then the most likely reason is that you are holding on to your breath and not exhaling constantly into the water. See our key article Your Know Your Problem, You Keep It All In. What else can make bilateral breathing hard? Having an overly long slow stroke.
So, when you move from breathing every 2 strokes to every 3 strokes, don’t think of it as one more stroke to hold your breath, think of it as one more stroke to exhale for.
The 2 week Bilateral hump（2周克服双侧换气“瘤”）
When we work with swimmers on their breathing in our 1-to-1 consultations and clinics, we find it takes them about 2 weeks of swimming (about 6 sessions) to get over the ‘bilateral hump’. For those first two weeks it takes perseverance and focus to breathe regularly to both sides.
Struggling to co-ordinate the strokes and breathing? Try standing in the shallow end of the pool, exhale into the water and perform practise strokes. Repeat bubble-bubble-breathe-bubble-bubble-breathe to yourself to help you develop the timing.
Fortunately after about 2 weeks things begin to get easier and bilateral breathing technique starts to require much less concentration and persistence.
So stick with it for 2 weeks, you will reach the light at the end of the tunnel!
Bilateral breathing is slightly controversial in the swimming world. Some swimming coaches working with struggling swimmers find it too hard to teach bilateral breathing to some individuals and give up, declaring it’s better to work on something else instead.
Similarly, many swimmers have attempted to learn bilateral breathing but have found it too hard and given up.
We know that swimmers who struggle with bilateral nearly always have a problem with their breathing technique: insufficient exhalation into the water.(我们知道那些正与双边换气苦苦挣扎的游泳者几乎总是在他们的呼吸技术上存在问题：水中吐气不尽。
Fix your exhalation, persist with breathing every 3 strokes and the door will open to a more symmetrical, faster, freestyle stroke.