From: Performance Diving International www.tdisdi.com
Disclaimer: this information does not constitute training and must be taught and practiced first under the supervision of an instructor.
When people talk about lung capacity most think size, the sheer volume of air in your chest. Increasing lung volume does help – it puts more gas in the tank. However freedivers should also be interested in how effectively and efficiently their lungs work. This article covers five tips which can help you increase your lung volume and efficiency.
The five steps outlined will help you:
- Increase your lung capacity
- Develop larger lung volume
- Give you more flexibility to allow you to equalize deeper
- Make your body more efficient in how it deals with hypoxia and elevated CO2
1. Segmented breathing
Segmented breathing is a process in which freedivers separate individual muscle groups used for breathing to maximize their potential. Most new and many untrained freedivers will breathe from their chest when asked to take the biggest breath they can. Unfortunately, this may feel natural, but it is entirely backward.
Think of filling your lungs like a jug of water. You start at the bottom and fill to the top. You do this exercise by breathing through pursed lips to help isolate your muscle groups and create a breathing pattern that maximizes the intake of air. Your diaphragm is a layer of muscle which separates the abdominal and chest cavities. It is also the most efficient muscle used in breathing. When you draw down on your diaphragm and out on your stomach, it draws air into your lungs, all the way to the bottom. This, coincidentally, is where two-thirds of the blood in your lungs resides. You’ll want to inhale until you can’t inhale any farther while using only your diaphragm.
If your chest starts to fill, you went too far. Do this four times, inhaling to the maximum. Then pause and relax for a second. Next, slowly exhale, holding the air back with just your tongue pressed against the roof of your mouth. Don’t use your diaphragm or chest to hold the air back. They should be completely relaxed.
Work your intercostal muscles
Now you start working your intercostal muscles. These surround your ribs. There are outer and inner intercostal muscles you use to inhale and exhale respectively. These are the muscles most people breathe with day-to-day. Chest out, stomach in, right?
While we might be accustomed to using them, the intercostal muscles aren’t as efficient as the diaphragm, for two reasons:
- More muscles mass uses more oxygen
- You’re flexing your ribs which are bone which takes effort
Expand your chest wall
The second part of segmented breathing is expanding your chest wall as much as you can. This takes time and practice. You start with your lower ribs and work your way up.
After you have done your four diaphragmatic inhalations:
- Do inhalations which start with inhaling as much as you can using just the diaphragm.
- Pause and relax.
- Then use your intercostal muscles to add on top of the diaphragmatic breath.
Once you’ve inhaled as much as you can, pause and relax. Then exhale slowly, again using the tongue against the roof of your mouth to slow the escaping air. You’ll want to repeat that process four times as well.
Use your shoulders
The final part of segmented breathing is using your shoulders. Yes, your shoulders. The tops of your lungs are just under the bottom of your shoulder, if you lift your shoulders, you lift the top of your lungs drawing in even more air. The key here is don’t lift your shoulders and hold them up. Simply lift them towards your ears as you open your epiglottis, allowing air to go past. Then close your epiglottis and immediately relax and drop your shoulders. Now:
- Perform the diaphragmatic inhalation, pause and relax.
- Then chest, pause and relax.
- Then shoulders, pause and relax.
- Then slowly exhale just like before, repeating four times.
Taking the five minutes to perform segmented breathing as little as three or four times a week helps develop larger and more efficient inhalations. The more air you can get in, and the more comfortably you can do it, the deep and longer you can go.
2. Inhalation or packing stretches
Inhalation stretches are also known as packing stretches. This exercise uses the steps covered in segmented breathing to help stretch muscle and bone out of the way of our lungs.
• Start by getting into a comfortable kneeling or sitting position, low to the ground. Relax for a minute, just breathing.
• Then perform a diaphragmatic breath, lock off your epiglottis, then with your right arm pointing up, lean to the left, so your right arm goes over you to the left.
• Hold this position for 10 seconds, then switch so your left arm is up and over while leaning to the right, holding this position for the same time.
• After this, put both arms above your head and lean forward arching your back, again holding for 10 seconds.
• Then put both arms behind you, either one hand grabbing the other or both hands on the ground behind you. Now press your sternum towards the sky for 10 seconds.
If you can’t get through all four positions on one breath, with practice you will. It’s okay to break it up in manageable parts.
After those four positions on a diaphragmatic inhalation, you’ll do the same process with the diaphragm and chest. Then diaphragm, chest and shoulders together. In this way you allow your muscles to warm up and get a progressively deeper stretch. Something to remember: If at any point you feel an uncomfortable tightness in your chest, or a tickle in your throat, back off on how much you are inhaling.
Then take some time stretching with less air until this no longer happens. It could take months, depending on your flexibility.
You can also experience lightheadedness as you increase the amount you inhale. This is due to the lungs applying pressure to the circulatory system, momentarily disrupting blood flow to the brain. Should you feel this, slowly exhale some and take a quick break. Then as you try again, don’t inhale quite as much. Work your way up to and eventually past that point.
3. Exhalation stretches
You may be asking how exhaling deeper and deeper will increase your lung capacity. This is an example of when lung capacity and a larger volume aren’t always the same. We all have what we call residual capacity. This is when you exhale, pushing as much air out of your lungs as you can. You still have some left and this is your residual capacity. The more flexible your chest and diaphragm are, the more you can draw from this as you equalize on your descent.
“Well, I don’t like going deep. I like to stay in the 10-20 m range.” Great, exhalation stretches will help. Within your respiratory muscles, you have what we call stretch receptors. These are the little guys that make a yawn feel so good, and a full exhalation so uncomfortable.
Stretch receptors signal the brain, telling it how much air your lungs are moving. If you could get flexible enough to be comfortable in the 50 m+ range, imagine how comfortable you would be in shallower water. More comfort equates to longer bottom time.
To perform an exhalation stretch, you will again want a comfortable kneeling or seated position low to the ground.
• The first stretch will essentially be a big sigh. Exhale until you would have to push from your stomach, then stop.
• Close off your epiglottis, then while leaning forward, try to draw a breath in against your closed epiglottis. This will draw your abdomen in and up, stretching your diaphragm.
• Hold that position for three to six seconds, then relax for a second or two, and repeat. You will want to perform the stretch three to four times, then breathe again.
If trying this for the first time, you may get the urge to breathe. Just relax through it. You’re teaching your body that compression is okay.
• After you do that three to four times, you will then perform a deeper exhalation, a relaxed sigh.
• Then push everything you can out with your stomach, but don’t bend over.
• Next, close off your epiglottis, lean over and perform the same series of stretches. After you have done this, exhale even further, pushing everything out with your stomach, then bend over while trying to exhale. Close off your epiglottis and perform the series of stretches.
Some freedivers like to perform the inhalation and exhalation stretches together: Inhale stretch, exhale stretch, deeper inhale stretch, deeper exhale stretch and so on. If at any time you get a tickle or cough lighten up on how much you are exhaling.
4. Carbon Dioxide (CO2) and Hypoxia (O2) tables
There is a way you can use oxygen more efficiently and increase what people frequently consider lung capacity. This is to make your body handle oxygen and carbon dioxide more efficiently. You can train for this using Carbon Dioxide (CO2) and Hypoxia (O2) tables.
As our cells use oxygen they produce carbon dioxide. The blood transports this back to our lungs where we exhale it. When we hold our breath, CO2 builds up because we aren’t exhaling.
The cerebral chemoreceptors in the brain are measuring pH and, in that way, measure how much CO2 we have in our system. Typically, the urge to get rid of CO2 is what drives us to breathe. We can build up a tolerance for lower levels of pH, which result from higher levels of CO2. We do this by slowly and systematically performing a series of breath holds.
Perform six to eight breath holds, each for the same length in time. Progressively decrease the interval (vent) between breath holds. In this way, you slowly build up the CO2 in your system. Given time and practice (and after completing the table on which you are working) you will increase the static times while decreasing the vent times, going up a table if you will.
Hypoxia tables (commonly called O2 tables) are the opposite of CO2 tables. The statics gradually increase while the vents remain constant. This decreases the available oxygen in your system, forcing your body to adapt to hypoxic conditions. Just like the CO2 tables, when you can complete one table, you bump up a table.
Two notes on tables: these are breath holds which you should never perform in the water without formal training and a trained buddy. You also don’t want to work the tables any time a loss of motor control or blackout could cause harm to you or someone else. In other words, no tables while stuck in rush hour traffic.
Also, it is normal to be on different CO2 and O2 tables. You might, for example, be on the level 10 CO2 table while also on the level 6 O2 table. If the table you are working is easy, you need to bump up. Just like in the gym, you don’t lift the easy weights to get better, you lift what’s hard.
5. Apnea walks
Apnea walks also help further develop tolerance to high CO2. But this requires a separate article.
Remember to always freedive with a buddy and continue your training. And before you hold your breath for any reason, ask, “If I blackout now, could I hurt myself or someone else?” If the answer is yes, pick another time or place or get a buddy to do safety for you.