My girlfriend & I have joined forces on an ebook geared towards providing anyone walking into a Bikram yoga class, whether newbie or veteran, with basic information about how their body functions when exercising in intense conditions, and what they need to know to take proper care of themselves.
(My girlfriend is a professional Bikram yoga instructor, and blogs here: http://yogamattes.com.)
You can see other sample chapters from the ebook about sweating, hydration, electrolytes and nerves either here on Planet Beast or over at her blog. Most of the chapters we’ve put up have been in order, but now we’re taking it out of order to share some basic information about the role of stretching in health and fitness. Again, the ebook is geared towards Bikram yoga students, but any kind of athlete could benefit from the info.
Proper stretching has a host of benefits for the body. When done regularly, stretching can help to improve range of motion (ROM,) can help prevent injuries and arthritis, relaxes the muscles, can increase flexibility, improve posture, help prevent hardening of arteries and increases blood-flow. Those who stretch regularly benefit more than those who stretch occasionally, and those who perform a variety of stretching exercises benefit more than those who only perform only one or two. By both those criteria, a regular yoga practice is just the ticket.
Types of stretching
There are actually four different types of stretching: ballistic, dynamic, proprioceptive neuromuscular facilitation, and static. Static stretching is the only kind we do in Bikram yoga class. As the name implies, static stretching is performed by stretching the muscle until a gentle tension is felt and held for a certain amount of time, or until muscular release is felt, without any movement or bouncing. The hold is static. This is an important distinction, because bouncing and moving “to get farther into the pose” is a common mistake made by beginners. This is ballistic stretching, which is an entirely different animal. Ballistic stretching exercises are a thing, but they are not at all like yoga exercises. Yoga poses are not designed to be performed ballistically, hence it is not safe, biomechanically, to treat them that way.
Physiology of Stretching
To understand the tight, pulling sensation experienced during stretching (called passive muscle tension,) it is necessary to look at the physiology of the muscles themselves, simplified to the aspects most relevant to our discussion. An individual muscle is made up of bundles of individual muscle cells. When you think of a body cell, you might imagine a little round glob with a single nucleus. Muscle cells, however, are different than other body cells. They are long threadlike things, which is why they are also called muscle fibers. They are incredibly thin—10 to 100 nanometers—but they generally run the entire length of the muscle they comprise, and can contain multiple nuclei. So, for instance, the individual threadlike muscle fibers that make up your biceps run the whole length of your upper arm; those that make up your hamstrings run the whole length of the back of your thigh, etc. We’ll see why in a moment.
Inside the outer membrane of the threadlike fiber is an even thinner fiber. This tiny inner fiber is called the myofibril. The myofibril, in turn, is made up of individual microscopic contractile filaments called sarcomeres. These sarcomeres facilitate the movement of skeletal muscles (the muscles that move your skeleton; the ones you use all day every day, whenever you do literally anything.) When the muscle fiber is stimulated to contract, these tiny overlapping filaments pull together. On and on down the chain, they pull together, causing the entire muscle to contract towards its origin point and pull against its insertion point. And because the skeletal muscle is anchored to a freely moving joint, the contraction pulls on the joint and causes its angle to be either increased or decreased, depending on what that particular muscle’s “job” is.
Think of a bodybuilder flexing his biceps. As his elbow bends, the biceps muscle suddenly looks larger and rounder. What’s happening? The microscopic sarcomeres inside the muscle fibers are pulling together and overlapping—rather than resting laid out along the upper arm in a long chain, they are piling up: the muscle is contracting. That same contraction is what causes the elbow to bend. Contracting towards its origin point in the shoulder, the muscle pulls on the opposite end—it exerts leverage against its insertion point in the elbow and causes the straight arm to bend. That’s why each muscle fiber runs the full length of the muscle—so they can exert a pull all the way from origin to insertion.
The cause of the passive resistance felt during stretching was once supposed to be extracellular (in the connective tissues,) but a study by Magid and Law demonstrated that it actually comes from within the myofibrils themselves.
What this means is, when you’re stretching, you’re stretching against the elastic resistance of those microscopic sarcomeres. And due to neurological safeguards against injury, it is normally impossible for adults to stretch most muscle groups to their fullest possible length without extensive training, due to muscle activation of antagonists as the stretched muscle reaches the limit of its normal range of motion. While stretching is highly beneficial to the body, over-stretching is detrimental. The body is wired to protect itself against over-stretching injury, and the upper limits we experience in our flexibility are often not mechanical limits at all but rather due our body’s hardwired resistance to the stretch itself.
Stated another way, some of the increases we see in our ability to stretch with practice are not due to increased capacity to stretch but rather increased neurological stretch-tolerance in muscles. Safe, effective stretching increases stretch-tolerance within a healthy, biomechanically sound range, thereby improving range of motion, better aligning joints and relieving chronic muscle tension. Another benefit of stretching is that it stimulates the production of synovial fluid (the fluid that pads and lubricates freely moving joints.)
Understanding that the passive resistance felt during a stretch comes from within the muscle itself illustrates an important principle in safe stretching: when stretching a muscle, it should be relaxed. Contracting the muscle, as we’ve seen, pulls the sarcomeres together, whereas stretching pulls against those sarcomeres. Thus, attempting to stretch a contracted muscle is physiologically unsound, because the muscle will be physically unable to stretch and the tension will be transferred to surrounding connective tissues. Ligaments and tendons do benefit from gentle stretching, but yoga poses are not designed to safely allow connective tissue to bear the full brunt of the stretch. That is not the intended effect of any pose. And yet, stretching against tight, contracted muscles tends to transfer the brunt of the stretch in exactly that way, potentially making the pose more conducive to causing soft-tissue injury. In short, you’re doing it wrong.
It’s a fact that essential oils have been used in various therapeutic applications for centuries, but there has generally been little published clinical research on their use. So we don’t have much hard data on their effectiveness in alleviating or attenuating the various conditions they are utilized in traditional medicine to treat. But this is starting to change lately, as a little spattering of scientific studies on essential oils are being conducted around the world.
There are a quite a few inherent difficulties for any study centered on essential oils. For one thing, that shit ain’t standardized. Unlike with a pharmaceutical drug, medical researchers can’t count on the fact that the chemical constitution of, say, lavender oil is exactly the same in all cases. The chemistry of an essential oil is inevitably going to be influenced by local geographical conditions, and weather conditions, as well as the season and the goddamn time of day when the plants are harvested. Additionally, how they are processed, and how they are packaged and stored, will affect the oils’ constitution. Each plant is unique in its chemistry, so essential oils are never exactly the same—this is obviously different from pharmaceutical drugs that are synthetically reproduced and are identical every time. It throws a wrench in the works when you’re studying something, if you can’t be sure that thing is, on a chemical level, exactly what you think it is.
Another problem is derived from the fact that it is difficult to conduct blinded studies with aromatic substances. Typically, research studies involve testing two groups—one group gets the experimental substance, whatever that may be, and another group gets a placebo substance (this group is referred to as the “control” group). When using aromatic substances, it is very difficult to conduct a blinded study, for the exact reason you would think. Basically, your subjects in a study are going to know whether you’re giving them a fucking beaker of lavender oil to sniff, or a beaker of saline solution.
But some researchers are finding ways to get around these difficulties, and conducting clinical studies on essential oils.
Preliminary controlled studies indicate that various forms of aromatherapy may have clinical applications in the reduction of anxiety experienced by patients with Alzheimer’s disease and other forms of dementia. For instance, one interestingly designed (albeit small-scale) study, a hospital ward was suffused with either lavender oil or water for two hours. An investigator then entered the ward and evaluated the behavior of the 15 residents, all of whom had dementia. (The investigator was unaware of the study’s design and wore a device to block inhalation of odors, because double-blind medical studies require both the researchers and the study-percipients to be unaware of whether the actual substance or the placebo has been delivered.) The results indicated that use of lavender oil aromatherapy modestly decreased agitated behavior.
It’s common, however, for patients suffering from dementia to lose their sense of smell, rendering the application of aromatherapy in dementia patents somewhat limited in its usefulness.
Essential oil of lemon balm has shown promise in this regard; in a double-blind study of 71 people with severe dementia, use of lotion containing essential oil of lemon balm reduced agitation compared to placebo lotion.
In a trial involving sixty-six women waiting to undergo highly anxiety-inducing surgical procedures, ten minutes of inhaling the aromas of essential oils of vetivert, bergamot, and geranium failed to reduce anxiety significantly, compared to placebo treatment. In another study, rosemary oil failed to reduce tension during an anxiety-provoking task, and conversely might have actually increased anxiety.
Another interesting complication involved in studying aromatic substances, is that human beings have a strong connectivity in our brains between memory and smell. Smells pull up a lot of emotional associations for us—it’s such an accepted fact that neurologists even have a pithy name for it: “nasal nostalgia.” So, if a subject smells rosemary and becomes anxious, how can a researcher possibly know if that’s due to some innate property of rosemary oil, or because that subject has just been reminded of the rosemary perfume his crazy aunt Mildred used to wear—the one who used to chase him around the house with her taxidermy cat when he was a child?
Yet another wrench in the works.
Still, some other clinical trails have actually revealed favorable effects. In one such study, researchers assessed the anxiety-level in three-hundred and forty individual dental patients, all waiting for dental appointments (who were all presumably about to flip their shit.) Those that inhaled the scent of lavender showed lower levels of anxiety compared to the control group. In another study, one-hundred and fifty patients were randomized into one of three treatment groups: control (standard care), standard care plus lavender, or placebo (standard care plus another kind of oil not thought to have any anti-anxiety effects). Those in the lavender group did actually experience an appreciable reduction in their level of anxiety.
Approaching the use of essential oils from a different angle, researchers have evaluated the effects of massage therapy done with essential oils on people suffering from anxiety and/or depression, while undergoing treatment for cancer. The treatment did appear to provide some short-term benefits to those patients. Again, absorption through the skin may have played a role here.
There is weak evidence to suggest that inhaled peppermint oil might relieve postsurgical nausea. Peppermint was associated with the attenuation of nausea symptoms in a small randomized trial of 35 women after nonemergency cesarean section, compared to placebo aromatherapy and standard antiemetic drugs.
Inhaled peppermint oil may also be useful in relieving mucus congestion of the lungs and sinuses—there is, however, only marginal supporting evidence for this application.
There is clinical research showing that an essential oil constituent (perillyl alcohol) has been successful in treating brain cancer. That’s a pretty frigging big claim, and calls for linkage:
So we know that in certain circumstances the constituents of essential oils can do big things. But that doesn’t necessarily display the effectiveness of the essential oils themselves—for instance, does inhalation necessarily lead to the same effects as other modes of administration? Maybe. Or maybe not.
In one rat study, bergamot essential oil inhibited the damage caused by “focal ischemia” (the same type of damage caused by stroke). The oil was injected, not inhaled.
Persistent anxiety is an all-to-common problem in the general population, and the pharmacological drugs used to treat it can often lead to sedation—hence the perennial search for alternative modes of treatment. Since the anxiolytic properties of lavender have already been demonstrated in some studies and small-scale clinical trials, like we’ve been looking at, a controlled clinical study was performed to evaluate the efficacy of “silexan,” an oral lavender oil capsule preparation. The lavender oil preparation was shown to be roughly as effective as pharmaceutical drugs (benzodiazepine) in the treatment of anxiety.
So what does all this say? Nothing other than what it says. There’s no broad, all-or-nothing take away, like “essential oils work!” or “essential oils don’t work.” (Sorry not to have a magic answer.) As time goes on, more and more evidence will be amassed both to debunk the effectiveness of oils in some applications, and to support their effectiveness in others.