High-altitude training in real conditions is obviously more feasible for athletes living in countries such as Kenya than those of us living in, say, Ireland, where the low-lying terrain reaches no higher than 1,000 meters. Similarly, high-intensity training may not be practical for some people, as it involves maximum physical effort and respiration until exhaustion. Some people will find high-intensity exercise extremely uncomfortable or find that they lose control of their breathing, which can lead to health concerns.
A practical alternative available to all athletes regardless of location and fitness is to supplement regular training with breath-hold training. In the following sections we will learn how breath-holding techniques allow us to simulate many of the positive benefits of high-altitude and high-intensity training, including:
• The release of red blood cells from the spleen, improving aerobic performance
• The production of natural EPO
• A higher tolerance to carbon dioxide
• Reduced stress and fatigue of working muscles
• Improved psychological preparedness
• Improved recovery time
• Reduced lactic acid
• Improved swimming technique (as discussed later)
• The ability to maintain fitness during rest or injury
• Maintenance of these benefits without the need to travel to high altitudes
For hundreds of thousands of years, breath holding was practiced extensively by our ancestors for the purposes of foraging for food by diving in a deep-water environment, and some evolutionary theorists even suggest that it might have been responsible for a number of unique human features. To this day, predominantly female Japanese pearl divers known as ama continue with the tradition of breath-hold diving—a practice thought to be over two thousand years old.
The best-equipped natural diver is likely the Weddell seal, which can remain submerged in water for up to two hours at a time. Although humans do not have the same adaptive physiological response of the seal, we are able to exhibit certain coping mechanisms in order to deal with a relative lack of oxygen. Generally, most humans can hold their breath after an inhalation for a maximum of up to about 50 seconds, with elite divers achieving a static breath hold of between 8 minutes 23 seconds and 11 minutes 35 seconds.
A number of studies have sought to understand the significant role that breath holding can play in adapting the body for increased oxygen delivery, with researchers investigating the effects of breath-hold diving in native divers, professional divers, and untrained divers.
The spleen is an organ that acts as a blood bank; when the body signals an increased demand for oxygen, the spleen releases stores of red blood cells. It therefore plays a very important role in regulating blood hematocrit (the percentage of red blood cells in the blood), as well as hemoglobin concentration.
Provoking the body to release additional red blood cells and increase the concentration of hemoglobin in the blood improves the body’s ability to deliver oxygen to working muscles during exercise. Breath-holding studies involving volunteers whose spleens had been removed for medical reasons demonstrate just how vital this organ is in changing the composition of the blood. After a series of short breath-holding exercises, those with spleens intact showed an increase in hematocrit and hemoglobin concentration of 6.4 percent and 3.3 percent respectively, while those without spleens showed no alterations in blood composition at all. This means that after as few as 5 breath holds, the oxygen-carrying capacity of the blood can be significantly improved with the help of the spleen.
This organ also influences how long a person can hold their breath for. In one study, participants were able to achieve their longest breath hold on their third attempt. Trained breath-hold divers peaked at a total of 143 seconds, untrained divers at 127 seconds, and splenectomized volunteers—those who had previously had their spleens removed—achieved 74 seconds. Not only that but spleen size decreased by a total of 20 percent in both breath-hold divers and the untrained volunteers, demonstrating a rapid contraction of the spleen in response to the reduction of oxygen. What this means is that breath-holding ability improves with repetition as the spleen contracts, releasing additional red blood cells into circulation and improving the oxygen-carrying capacity of the body. While these studies generally include subjects holding their breath for as long as possible, significant splenic contraction has been found to take place with even very short breath holds of 30 seconds. However, the strongest contractions of the spleen, and therefore the greatest changes to blood composition, are shown following maximum breath holds.
Another useful piece of information gleaned from these studies is that it is not necessary to be immersed in water to benefit from the effects of breath-hold diving. There seems to be no discernible difference between the increase of hematocrit and hemoglobin concentration in volunteers practicing breath holds in and out of water. Since there is no visible increase in the results of breath holding with the face immersed in water, it can be concluded that it is the breath hold itself that stimulates splenic contraction. In other words, it is not being underwater that causes the spleen to release red blood cells into the circulation but the simple drop of oxygen pressure in the blood resulting from holding of the breath. Therefore, the benefits of breath holding are not limited to divers and swimmers. This is of particular relevance to the Oxygen Advantage program, as our breath-hold exercises are performed out of water.
The relevance of the above studies suggests that effects similar to those achieved with high-altitude training can be obtained at sea level simply by performing a series of breath holds. Stimulating the spleen to contract by reducing the availability of oxygen causes an increase in hemoglobin and hematocrit, which in turn increases the oxygen-carrying capacity of the blood and improves aerobic ability.
The most appealing aspect of breath holding is that it is feasible for most individuals and is not as taxing on the body as high-intensity exercise. Performing just 3 to 5 breath holds of maximum duration can lead to a 2 to 4 percent increase in hemoglobin. This might not sound like much, but where a fraction of a second can determine the difference between the winner and the loser, every possible advantage counts.
Why Oxygen Advantage Training Elicits an Even Stronger Response
In the studies investigating breath holds and splenic contractions discussed, each breath hold was performed following an inhalation. You might be wondering why Oxygen Advantage breath holds are performed after an exhalation. Let me explain.
Performing a breath hold after an exhalation lowers the oxygen saturation of the blood to simulate the effects of high-altitude training. I have monitored the blood oxygen saturation of thousands of individuals as they practice breath holds, and by far the greatest change to oxygen saturation occurs after an exhalation. For most people, after four or five days of practice, a drop of oxygen saturation below 94 percent can be observed—a level comparative to the effects of living at an altitude of 2,500 to 4,000 meters.
Gently exhaling prior to holding the breath reduces air content in the lungs, allowing a quicker buildup of carbon dioxide and eliciting a stronger response. While this reduces the length of time for which you can hold your breath, increased carbon dioxide has been shown to improve hemoglobin concentration by around 10 percent compared to a breath hold with normal carbon dioxide.
Higher levels of carbon dioxide in the blood can produce an even greater contraction of the spleen, resulting in an increase in the release of red blood cells and therefore the oxygenation of the blood.
Increased CO2 in the blood also causes a rightward shift of the oxyhemoglobin dissociation curve. As described by the Bohr Effect, an increase in carbon dioxide decreases blood pH and causes oxygen to be offloaded from hemoglobin to the tissues, further reducing blood oxygen saturation.
Holding the breath on the exhale also capitalizes on the benefits of nitric oxide by carrying the gas into the lungs rather than expelling it. By exhaling and holding t
he breath, nitric oxide is able to pool in the nasal cavity so that when breathing resumes, air laden with nitric oxide is inhaled into the lungs.
Increase Erythropoietin (EPO) Naturally
As we have seen, erythropoietin, often known as EPO, is a hormone secreted by the kidneys in response to reduced oxygen levels in the blood. One of the functions of EPO is stimulating the maturation of red blood cells in the bone marrow, thereby increasing oxygen delivery to muscles. Breath holding is an effective way of stimulating the release of EPO, allowing you to fuel your blood with increased levels of oxygen and enhance your sports performance. The concentration of EPO can increase by as much as 24 percent when the body is subjected to lower oxygen levels using breath-hold exercises.
A clear example of the relationship between breath holding and EPO production can be found in those suffering from sleep apnea. Sleep apnea is a condition involving involuntary holding of the breath after exhalation during sleep. Depending on the severity, the sleeper may hold their breath from 10 to 80 seconds, and this may occur up to 70 times an hour. During sleep apnea, the oxygen saturation of the blood with oxygen can reduce from normal levels of around 98 percent to as low as 50 percent. These reduced oxygen levels can cause an increase in EPO of 20 percent.
Of course, there is quite a difference between the condition of sleep apnea and the practice of breath holding to enhance sports performance. However, it is interesting to note the effect of breath holding (both voluntary and involuntary) on the production of natural EPO. Increasing EPO levels allows the blood to deliver greater amounts of oxygen to the muscles and is the natural equivalent of the illegal blood doping methods discussed at the beginning of this chapter. The benefit of using breath holding as a performance-enhancing exercise is that, unlike sleep apnea, conscious breath holding allows you to keep complete control over the frequency and duration of each hold. And, unlike blood doping, the EPO you produce using simple breathing techniques is free, effective, and legal.
The Importance of Movement for Simulating High-Altitude Training
During physical exercise or breath holding, a shortage of air is created. An air shortage is best described as a hunger or desire to breathe, varying in intensity from mild to moderate to strong. The intensity of air shortage will differ depending on the exercise or situation. For example, while practicing the exercises in this book, the air shortage during sitting should be mild or tolerable whereas the air shortage during intense physical exercise can be strong. A strong air shortage during physical exercise is beneficial during training as it conditions the body to tolerate extreme demands, and is often popular among athletes as it presents a new challenge to pit their willpower and determination against.
A strong air shortage during physical exercise is more suitable for athletes with a BOLT score of longer than 20 seconds. When your BOLT score is shorter than 20 seconds, you must be careful not to hold the breath for too long as it can cause a loss of control of your breathing. It is important that you are always able to resume calm breathing following a breath hold. The shorter the BOLT score, the easier it is to lose control of your breathing.
Please note that when creating an intense air shortage you may develop a headache as your blood oxygen saturation decreases, but this should disappear after about 10 minutes of rest. Try to avoid overdoing the exercises to the point that they bring on a headache.
Breath Holding to Improve Respiratory Muscle Strength
The respiratory center is located in the brainstem and continuously monitors blood oxygen, carbon dioxide, and blood pH, using this information to control the amount of air taken into the body. When the body requires a breath of fresh air, the brain sends a message to the respiratory muscles, telling them to breathe. The diaphragm, which is the main breathing muscle, moves downward, creating negative pressure in the chest cavity, resulting in an inhalation. Following inhalation, another message is sent for the diaphragm to move back to its resting position, causing an exhalation.
When the breath is held following an exhalation, the intake of oxygen is halted while carbon dioxide accumulates in the blood. During this pause, oxygen cannot enter the lungs, and carbon dioxide cannot leave the bloodstream. The respiratory center, noticing the change to blood gases, communicates to the diaphragm to resume breathing, and the diaphragm contracts downward in an attempt to allow the body to breathe. However, breathing cannot resume while the breath is held, and the brain begins to send increasingly frequent messages to the diaphragm, causing its spasms to intensify. You can experience this by simply holding your breath until you feel a strong need to breathe. At first you will feel an isolated spasm of the diaphragm, but this will soon be followed by more intense and quicker spasms as the body attempts to resume breathing.
In essence, holding the breath until a medium to strong need for air mobilizes the diaphragm, provides it with a workout and helps to strengthen it. While there are many products on the market aimed at increasing respiratory muscle strength, breath holding may be the easiest and most natural as it can be employed at any time and actively directs attention to the diaphragm. Improving respiratory muscle strength can be extremely beneficial during exercise, especially when fatigue of the diaphragm may determine exercise tolerance and endurance.
Breath Holding to Reduce Lactic Acid
Just as injury plays a role in limiting physical performance, mental and physical fatigue can also prevent an athlete from pushing harder and faster. As U.S. Army general George Patton wrote to his troops during World War II: “Fatigue makes cowards of us all. Men in condition do not tire.” And he was right; endurance is relative to how well the body is prepared, and the onset of fatigue occurs when the body is pushed beyond the limits of preparation.
Working a muscle without sufficient fuel generates lactic acid, and while small amounts can be beneficial, acting as a temporary energy source, a buildup of lactic acid creates a burning or cramping sensation in the muscle that can slow down or even halt exercise completely.
Studies with athletes have demonstrated that breath holding after an exhalation deliberately exposes the body to higher levels of acidity, thereby improving tolerance and delaying the onset of fatigue during competition.
In a team sport like football, where players are expected to maintain form and concentration during 90 minutes of intense activity, the ability to push through or avoid fatigue can be instrumental to a team’s success. I recently worked with the Galway women’s football team, whose coach, Don O’Riordan, was concerned that the players were tiring during the last 15 minutes of a game. When fatigue sets in, muscles tire, work rate slows, and in some respects there is a loss of interest and focus—a situation almost guaranteed to hand victory to the other side. Breaking through the barrier of fatigue can be as much about psychological resilience as physiological endurance, and breath-holding exercises offer a useful technique for improving both.
In order to replicate the conditions of a game, the team’s training usually lasted the length of a full match. Their training session consisted of a warm-up and a 10-minute run followed by match practice and tactics. The last 15 minutes included drills and interval training such as running back and forth between cones set at different distances. To incorporate the Oxygen Advantage program as seamlessly as possible into this type of session, I made only modest changes to the existing routine so that the players could adapt to new breathing techniques while maintaining their current form. The result not only increased the effectiveness of the training, but also the players’ endurance and performance during competition.
During the 10-minute run at the beginning of training, I instructed the players to switch from their usual habit of breathing through their mouth to running at a comfortable pace with their mouth closed. Every minute or so, each player exhaled and held their breath until they felt a medium to strong air shortage. No changes were made to the match practice portion of the training session, as the introduction of nasal breathing adds an extra load to the body that can i
nitially slow down an athlete, and possibly lead to deconditioning of leg strength. The better approach, therefore, was to incorporate nasal breathing into the 10-minute run and the final 15 minutes of interval training only.
Since the team had a tendency to experience fatigue during the remaining 15 minutes of a game, introducing nasal breathing to the final interval training session added an increased challenge. Running flat out from cone to cone with the mouth closed is no mean feat, and although a couple of the players experienced mild headaches during the first session, the team adapted to it easily. After a few more practice sessions, the players had adapted well to the demands of nasal breathing, so I decided to challenge them further by introducing breath-hold exercises. These exercises (which can be found in the next chapter) subjected the players to an even greater feeling of breathlessness and worked to further delay the onset of fatigue.
Bicarbonate of Soda—More Than Just a Cooking Ingredient!
In a similar way that breath holding delays the onset of fatigue during sports, countless studies have shown that taking the alkaline agent bicarbonate of soda reduces acidity in the blood to improve endurance. Who would have thought that a cooking ingredient found in almost every kitchen cupboard in the Western world could also improve sports performance? Not only that, but it is a very helpful tool to reduce your breathing volume and increase your BOLT score.
Bicarbonate of soda is a salt that is found dissolved in many natural mineral springs and is usually sold as baking soda, bread soda, or cooking soda. This ingredient has a wide variety of uses ranging from baking to brushing your teeth to cleaning your fridge.
Taken internally, bicarbonate of soda helps to maintain pH of the blood, and it’s also the active ingredient in a number of over-the-counter antacid medications. Dr. Joseph Mercola, a leading authority on natural health, suggests taking bicarbonate of soda for the relief of a number of ailments, including ulcer pain, insect bites, and gum disease.
The Oxygen Advantage: The Simple, Scientifically Proven Breathing Techniques for a Healthier, Slimmer, Faster, and Fitter You Page 11
