The out-breath is a brake
- Breathing inheart speedsBreathing outheart slows
Picture the heart and the lungs, side by side. They are wired together. As the lungs fill, the heart speeds up a little. As they empty, it slows a little. This happens with every breath, awake or asleep, without anyone deciding it. The swing is small, and it is the body's own brake.
- The acceleratorthe alarm systemThe brakethe long nerve
The body has two pedals. One is the accelerator: the alarm system that sends adrenaline and speeds the heart. The other is the brake: a long nerve from the brain to the heart and the gut that slows things down. The brake is strongest on the out-breath. That is the wiring, measured on anyone wearing a heart monitor.
- Breathing inBreathing out
On which half of the breath is the brake strongest?
Neither; the heart does not change with breathing.
Not yet. It does, on every breath, by a few beats. The change is small enough not to feel and large enough to measure on any monitor.Breathing in.
Not yet. Breathing in is when the heart speeds up a little, because the brake eases off to let more blood through the filling lungs. The brake presses on the way out.Breathing out.
Right. The brake eases off on the in-breath to let more blood through the filling lungs, and presses on the way out. Every breath is one small press. - At rest10 swing, made upUnder alarm3 swing, made up
The heart's swing with each breath. People who measure this count the swing: how much faster on the in-breath, how much slower on the out. A big swing means a brake that is working well. Under alarm the swing shrinks, because the accelerator is pressed and the brake is let off. The size of the swing is a reading of which pedal is down.
Move the control to set how many breaths a minute. The swing of the heart is made up and round, shaped on what the monitors show: slower breaths give the brake longer on each out-breath.
The heart's swing3 out of 10The biggest swing10 out of 1020Twenty breaths a minute, fast and shallow. Each out-breath lasts about a second and a half. The brake barely presses. Swing 3.
The heart's swing5 out of 10The biggest swing10 out of 1015Fifteen a minute, a normal resting rate. Two seconds per out-breath. The brake presses a little on each. Swing 5.
The heart's swing8 out of 10The biggest swing10 out of 1010Ten a minute. Three seconds per out-breath. The brake has time to press. Swing 8.
The heart's swing10 out of 10The biggest swing10 out of 106Six a minute. Each out-breath is about five or six seconds. The researchers found the swing is at its biggest near here. Swing 10.
The heart's swing8 out of 10The biggest swing10 out of 104Four a minute. The lungs are held too long on each half, and the swing comes back down. Swing 8.
At which rate was the swing biggest?
Four a minute. The slower the better.
Not yet. Slower helps until about six a minute, and past that the lungs are held too long on each half. The biggest swing is near six, not at the slowest the control allows.About six a minute.
Right. Six a minute gives the brake about five seconds on each out-breath, which is where the labs find the swing largest for most people.Twenty a minute. More breaths, more brake.
Not yet. More breaths means shorter out-breaths, and the brake presses on the out-breath. Twenty a minute gives it a second and a half each time, and the swing is at its smallest.Move the control.
- about 4 secondsInabout 6 secondsOut
Six breaths a minute is ten seconds a breath: about four in, six out. That is the rate at which the heart's swing is largest for most people, measured in labs for decades. It is not a trick. It is where the brake has the longest press on each out-breath.
- One minute60 secondsSix breathshow long each?
At six breaths a minute, how many seconds does one breath take?
secondsSixty seconds, shared equally among six.
Right. Ten. Sixty seconds shared among six breaths. Most adults at rest take twelve to twenty a minute, which is three to five seconds a breath, so six is about half the usual speed. - The acceleratorfast and loudThe brakeslow and quiet
So the alarm from a silence has a brake sitting next to it, pressed a little on every out-breath. The alarm is fast and loud. The brake is slow and quiet. The body was built with both, and the out-breath is where the second one lives.
- The singerlong notesThe brake
A singer holds long notes, breathing out slowly for most of a song. By this lesson, what is the brake doing during the song?
Pressing for longer on each note, because a long out-breath is where the brake lives.
Right. A held note is a long out-breath, and the brake presses on the out-breath. The song's shape is giving the brake a long press, whatever the singer feels.Nothing. Singing is about the lungs, not the heart.
Not yet. The lungs and the heart are wired together, which is the first thing this lesson said. A long out-breath is a long press on the brake, whether the person is singing or not.Letting off, because performing is stressful.
Not yet. The nerves of performing press the accelerator, and the long out-breaths press the brake. Both can be true in one song; the song's shape is giving the brake a long press anyway.
Lesson complete
The heart speeds on the in-breath and slows on the out-breath; the slowing is the body's own brake.