Compression: It it for Real?
Compression garments have become very popular among both recreational and professional athletes . At the same time, there are more than a few who scoff at the very idea of compression clothing, considering it to be an expensive novelty. In this article we will delve into the science of compression garments to reveal the unbiased truth.
What are Compression Garments?
Compression garments have been widely adopted for use in sporting contexts. The types of garments available vary and include those that cover the torso and the arms in full or part, the lower-body from the waist in full or part, and those that cover speciﬁc limb-segments only (e.g. sleeves, socks, and stockings). While the type of garments used and the time of wearing them can vary by sport, personal preference, and intended purpose, a common feature is that all compression garments apply pressure to and cover body surfaces.
Let’s consider these two aspects a little more closely . . .
A fundamental assumption underpinning compression garment use is that the pressures applied to the body are important in some way. During use, these pressures can be inﬂuenced by garment properties (e.g. garment dimensions, garment construction, properties of the constituent fabrics and how these change over time) and characteristics of the underlying body segment (e.g. body dimensions, tissue type, and changes related to posture and movement).
Compression garments come in all shapes and sizes. The most commonly used in a gym and CrossFit setting are compression socks, knee sleeves and arm sleeves. However, you can also get compression garments that cover the torso, and thighs.
Understanding the Science
To gain a full appreciation of how compression garments can benefit you, it pays to have a basic understanding of the circulatory system. The heart pumps blood around the body through the arteries. Blood contains oxygen and nutrients from your food which is vital to the function of every cell in the body. When the oxygen is used up by the cells, the deoxygenated blood takes lactic acid and waste products away from the cell through the veins. After returning to the heart, the blood is reoxygenated and the process repeats endlessly.
In order to perform at your best you need an efficient circulatory system in which oxygenated blood is flowing freely through the body. The more oxygen your cells can get, the more efficient your muscles will work and the more effective your aerobic system will work. Just as important is the efficient removal of lactic acid and other waste products that are the result of the muscles working through exercise. If it isn’t, you will experience muscle soreness and your performance will be impaired.
Something else which negatively impacts upon exercise performance is local muscle fatigue. One thing that increases this fatigue, without producing benefits in the form of muscle hypertrophy or strength enhancement, is muscle vibration. Vibration occurs when you perform an action repeatedly. The prime example is running. The constant foot strike on the running surface results in repeated pounding and vibration through the ankle, calf, knee and quadriceps.
So, how can wearing a compression garment help to improve circulation and reduce vibration?
Compression garments feature what is known as graduated compression. This simply means that the compression decreases as the garment goes up the body. Let’s take a look at a compression sock as an example; the foot of the sock has the highest level of compression, with the effect that it it the tightest fitting. As you move in the ankle the compression is a little less, with the calf area having the lowest level of compression.
The effect of graduated compression is that it helps to counter the downward effects of gravity on blood flow. It helps the deoxygenated blood to more quickly return to the heart, more rapidly taking lactic acid and waste products away from the target area.
Compression garments will also help to stabilize the covered area during exercise, such as running. This will have the effect of reducing vibration and the muscle stress that results from it.
How Effective Are They Really?
Athletes specializing in different endurance sports such as cycling, running, or cross country skiing wear socks, sleeves, shorts, tights, and/or shirts or long sleeves shirts or whole body suits with compression to improve their performance and facilitate recovery. Companies promote the application of compression clothing and advertise ergogenic effects, improved recovery and perception. Accordingly, athletes and coaches consider compression clothing as an essential external aid to provide beneﬁts for endurance performance and recovery.
So what does the research have to say on the subject? In 2015, a German meta-study was undertaken by Engel, Stockinger, Wall, et al. On the basis of 55 studies, it was shown that the use of compression has no effect on performance in running (400 m–42.195 km), ice speed skating, triathlon, cross country skiing and kayaking. Apparently, by wearing compression garments cyclists might slightly improve variables related to time trial performance (1).
A risk of impaired performance due to hyperthermia could not be confirmed when wearing compression garments, however compression clothing increased skin temperature. Furthermore, the results showed that physiological parameters like VO2max, VO2peak, submaximal oxygen uptake, blood lactate concentration, heart rate, blood saturation and partial pressure of oxygen are mostly not altered by wearing compression clothing during endurance exercise.
The researchers concluded that if compression clothing is worn during and following intense or prolonged endurance exercise athletes should beneﬁt from improved lactate elimination, reduced muscle pain, damage and inﬂammation during recovery. These processes are likely due to reductions of muscle oscillation during exercise, improvements in clearance of metabolites through improved blood ﬂow, lymphatic outﬂow and reduced space for swelling. Potentially, this might improve recovery and enhance subsequent performance.
Anecdotal feedback from users confirms these results. Users do not generally report improved sports or athletic performance, which is something that manufacturers often promote as a benefit. However, they do report a reduced amount of delayed onset muscle soreness following exercise, reduced muscle vibration and less swelling post exercise.
If you have an existing injuring, be it a swelling, sprain or shin splints, calf cramp or even Achilles tendonitis, a compression sock or sleeve will help you. As a result of the enhanced bracing and improved venous blood flow which removes waste products from the area more quickly, you will reduce discomfort while training.
Compression garments, however, are not a treatment replacement. They are an ergogenic aid that will help you to get through your training when you have an injury. You should also be treating your problem area with the common sense methods that are well established. Firstly, get the injury checked so that you can find out exactly what the problem is. The most important treatment is rest, followed by massage, stretching and strengthening and wearing footwear that is customized to you.
Another consideration that is worth noting is that it is likely that ‘off the shelf’ compression garments do not exert the same compression pressures in every individual. Compression garments are often ﬁtted according to the height and mass of an individual. Given the variation in body sizes within a population it is unlikely that all individuals will receive appropriate levels of compression. It is likely that a number of individuals using compression garments are not receiving adequate levels of pressure to be of beneﬁt.
If the level of compression exerted by the garment is insufﬁcient then the garment will not be able to contain the edema associated with the inﬂammatory response nor will it modulate venous return both of which are mechanisms by which compression is proposed to be of beneﬁt. This has implications for athletes wishing to use these garments as a recovery strategy and indicates the importance of measuring the exact levels of compression exerted by garments on each individual.
Of course, compression garments can also help those who are not suffering an injury. While there is no solid evidence that the improved blood flow will actually improve your physical performance, it will reduce your post exercise soreness and recover more quickly.
Socks or Sleeves?
Should you invest in a compression sock or a sleeve?
If you are wanting to protect the ankle, instep or achilles as the result of some sort of injury then you should go for a compression sock. This will ensure that your whole foot benefits from the increased blood flow effects of graduated compression.
However, if your tender area is further up your leg (calf, knee or quadriceps) you should opt for a compression sleeve.
In addition to your sporting and exercise endeavours, you should wear a pair of compression socks when you are travelling in the air (or any other vehicle for that matter). When you are sitting for an extended period of time, the blood flow through your legs is negatively impacted. The graduated compression that you get when you wear compression socks will help the venous blood flow so that the life giving circulatory system is uninterrupted.