Why is it that we don’t often breath to our full capacity, we take shallow breathes and rarely take full breath


Why is it that we don’t often breath to our full capacity, we take shallow breathes and rarely take full breath

In: 680

A similar reason to why you walk some places and aren’t in a full out sprint everywhere, it’s just easier

You don’t need full lung capacity during the day to day, the extra expansion is for intensive movement. Otherwise you’d be breathing rapid fire trying to get your O2 up while exerting yourself.

When your body is at rest, respiration doesn’t need to be working at 100%. The few times you take full breaths (yawns) is because you feel drowsy because of lack of oxygen

Under normal circumstances, we don’t *need* to take a full breath on every inhalation; our body gets enough oxygen to maintain organ and cell function through normal respiration.

Taking a deep breath (or a series of shorter breaths) *is* helpful if you expect to exert yourself in some way, though, because you’ll want that extra oxygen in your bloodstream to offset the expenditure of O^(2) from increased muscle use and respiratory requirements.

same as why cars can drive 120 kms but normally do 60 km. it’s better to design with higher capacity to reduce strain for everyday use than to always be hitting the limit.

There’s evolutionary advantage to having excess lung capacity relative to normal needs. Most of the time we don’t need it, but it significantly improves your chances of staying in the gene pool if you have it when it’s needed.

We actually do take large breaths every 5 minutes or so. When they used to have old breathing apparatus many people died, when they introduced a large breath every x minutes the death rate reduced.

You know the process of breathing and how its a very repetitive process that we do nonstop every day?

Well here’s the thing: if we repeatedly expand the lung over and over to the max capacity nonstop it will cause damage, and unlike muscle that is designed to be damaged and repaired within days, lung damage are slower to repair.

And here’s the thing: on average we consume 5% of the air we breathe in because inspiration and expiration happen at a fixed rate. Increasing total air in the lung will not have a significant increase in efficiency, but will result in higher energy expended.

There’s just no beneficial reason to actually take full breathe when not doing anything..

There’s a big point being missed: what does breathing do?

Sure, you are able to introduce oxygen to your blood, but that also means removing CO2 as the increased levels from your body working like to mix evenly with the open air if they can.

If you force yourself to breathe more than you need to, that CO2 responsible for adding acidity to your blood will leave and you will increase blood ph. While acidity is bad in terms of damaging cells (think battery acid on the extreme) high ph will cause the same outcome of cell death like bleach (again, another extreme).

When you exercise, it isn’t an issue to breathe more because the acidity buildup from co2 increases to balance the exhalation losses.

CO2 is also responsible for the dilation and constriction of blood vessels in different places of the body to encourage bloodflow where it is most beneficial. Ex: muscles when excersizing and stomach when digesting food

TL:DR sure you need oxygen for energy, but the carbon dioxide you keep in your blood by not breathing too much is important for preventing cell damage and encouraging certain functions


Your full lung size is designed to work and sustain you during intense exercise.

You only need a bit of it in normal life.

It’s better for your baseline to be undemanding. If you needed your full capacity to do basic stuff, there’d be no way to get more air when it’s really important, like you need to run for your life.

I’d like to add anecdotally that when I am having a tense day at work I breathe less fully, less often, and even clench my teeth.

A similar analogy is to movement of our bodies. We can crawl, roll, wiggle, walk, run, jump, sprint whoever we want to move somewhere else. However we walk because it takes the least amount of energy to do. We call have different speeds for that walking but it’s roughly the same among different people.

The same thing is true with breathing. The lung has a certain amount of compliance, or ease of expansion. Also the small the lungs become, the more force it takes to open up because you are fighting the hydrostatic forces of water within the lung. The bigger they get, now there is recoil affect from the lungs that pulls them back in. Basically there is a sweet spot there that allows us to breath without fighting as much recoil and hydrostatic pressures. That zone allows us to breath without increased amount of work and we call this zone of breathing the resting tidal volume. That extra breath above normal breathing is call the inspiration reserve capacity. The amount we can breath out from baseline is the expiratory reserve capacity. And the total amount of all three together is called the forced vital capacity. However we don’t need to use the forced vital capacity for most people because we have more lung tissue than we need (for most people) and makes it so we don’t need that extra air to come in to make up for it. Basically it uses lots of energy to use all of that lung like that and is why people that have bad lung disease tend to become so skinny (burning too much energy to breath).

Have you ever tried deep breathing for an extended period of time? It’s EXHAUSTING.

It’s sort of the same reason why we don’t drive our cars with the throttle wide open all the time…

Side note. It took me a year to stop breathing with just my chest and to breath with my belly.

Many of us (at least in US where I live) don’t know how. We breathe through our bellies as babies, but it is rarely reinforced by parents while growing up. We end up mostly breathing through our chests instead. Getting into yoga was how I learned full body breathing again

It’s efficiency vs peak

A lot of processes and systems within the body are designed to move at the most efficient speed possible, a more balanced longevity kind of way. Then almost all of them have the ability to kick into high gear

It’s just a function of how we evolved, in times of scarcity you don’t want to waste energy, but if you’re being hunted or hunting then you need to stay competitive

I see a lot of people here missing one of the big points: We breathe primarily to get rid of carbon dioxide, not to get more oxygen. In fact, if we didn’t make any carbon dioxide as a waste product at all, we would only have to take a single breath every 3 minutes to function fine. This is because our bodies make carbon dioxide much faster than we lose oxygen.

Taking a shallow breath means we get rid of carbon dioxide more quickly, because more exchanges happen via diffusion in the lungs. And because carbon dioxide buildup happens quicker than oxygen depletion, shallow breaths are an efficient way of pumping carbon out.

But, deeper breaths take *in* more oxygen. We don’t do this simply because your body doesn’t need that much oxygen in a normal setting, such as when you are lying in bed. So there is no point taking a deeper breath. Taking a deeper breath is useful however, when you are doing something energy intensive (e.g. running!) which is when you’ll start panting.

**Fun fact:** You do need to take occasional deep breaths (often called alveolar breaths) as they re-inflate tiny sacs in your lungs (alveoli) that absorb oxygen into your blood and can stick together over time due to surface tension.

This re-increases the surface area of your lungs to full, resulting in more oxygen transferring per breath.

It’s why originally people didn’t live for long in “iron lungs” as they neglected to realise how important “sighing” was in this/the necessary re-inflation of alveoli, and regular shallow breathing was unhealthy over time.

It’s also a neat energy hack… if you’re ever feeling sluggish, take a breath, pause then take another one (before breathing out) and this will re-inflate your lungs fully and should give you a small energy boost.