What Compression Shorts Really Do
Compression gear is all the rage among resistance trainees, athletes, and runners. People are spending a fortune on compression shorts, shirts, socks, even underwear, all without knowing what they really do.
Don't get caught up in the hype! Here is the science explaining what compression gear does:
Create Positive Pressure – Compression garments create positive pressure across the one-way valves in your blood veins, reducing the risk of blood clots and varicose veins. It can prevent blood pooling in your ankles and feet as you run, cycle, or train on the elliptical machine. It will also improve circulation and keep blood flowing efficiently.
Reduce Soreness – A 2007 study found that compression socks used during a 10K run helped to prevent DOMS (delayed onset muscle soreness). Only two of the participants who wore the compression socks were sore after the race, but 13 of those who didn't wear the socks felt the same soreness.
Improve Running Performance – A 2009 study found that using compression stockings improved running performance at both the anaerobic and aerobic thresholds. The improvement may have been slight, but visible enough for it to be important.
Reduced Lactic Acid Levels – A 2014 study found that compression garments could help to reduce blood lactate levels after intense exercise. Though the garments didn't improve performance in this study, it did help to reduce lactate levels within 1 minute after exercise.
Protect Muscular Power – A 2011 study found that using compression garments can help to protect muscular power after endurance exercise.
As you can see, there are a few benefits of compression garments as proven by science. However, be warned: these tests all involved compression SOCKS, not shorts. No studies have been done on the benefits of compression garments worn on the upper legs, thighs, and glutes. While it's possible the above-mentioned benefits remain, there's no science to back it up.
The real use of compression shorts is to reduce chafing. Compression shorts are tight-fitting garments that keep everything securely in place as you run, jump, and play. The moisture-wicking fabric pulls sweat away from your skin and prevents salt crystals forming. This leads to less friction, ergo less chafing. Compression shorts can also keep your muscles warm, preventing muscle strains.
Are compression shorts better than any other running or cycling shorts/tights? Given the scientific evidence available, it's possible the answer is "yes". If the shorts really can improve performance, reduce soreness, lower lactate levels, and protect your muscle power after endurance training, they're worth it.
Compression Shorts Grades
Not all compression shorts are the same! Style and fabric aside, there's only one truly important factor to consider: the compression grade.
Medical-grade compression garments are usually recommended to diabetics and people with vascular disorders. Their compression ranges from 30 to 40 mmHg. They are not usually designed for active wear, but are made of more delicate materials intended for comfort and greater compression instead of durability. You don't need to buy them at a pharmacy or get a prescription for them, but they're available online and at a number of retailers. However, you need to know they're for treating medical conditions, not to use during sports. The high grade of compression can actually have NEGATIVE effects on athletic performance.
High-grade compression garments don't offer medical-grade compression (above 30 mmHg), but opt for firm compression (20 to 30 mmHg). Though they can be used for varicose veins or other vascular problems, they're manufactured with athletic use in mind. They're made of durable, moisture-wicking materials that provide both comfort and firmness. The lack of stitching will reduce friction as you exercise, and they're intended for professional athletes, regular resistance trainees, and distance runners.
Mid-grade compression garments tend to offer medium compression (15 to 20 mmHg), which is perfect for people who are active but don't spend hours a day engaged in endurance exercise. They can be used by strength trainees, HIITers, CrossFitters, and other people who need flexibility and unimpaired movement from their compression garments. The materials are still moisture-wicking and comfortable, but the price tag is slightly lower than the top-of-the-line, high-grade compression garments.
Support shorts are more underwear than outerwear, meaning they'll be soft, comfortable, and keep your junk secure as you move. The grade of compression is usually much lower (8 to 15 mmHg). The durability of the material is still excellent, but the shorts are more for comfort than for athletic performance.
Compression Shorts Underwear vs. Outerwear
Did you know that some compression shorts are actually designed to be used as underwear? Just like your Spandex running tights, they're intended to be worn beneath your regular shorts.
So what's the difference? How can you tell compression underwear apart from compression outerwear?
Underwear – Compression underwear will strongly resemble your basic Spandex boxer briefs, though slightly longer in the leg than most underwear. They're more likely to end at mid-thigh, offering good upper leg compression. The fit will be tight around the glutes, thighs, and legs, providing the compression that keeps blood flowing as you work out.
The fabric will usually be soft and incredibly comfortable, but not the most durable. This isn't a problem because they're intended to be worn beneath shorts, pants, or other protective outerwear. The material will receive less wear and tear because they are underwear.
Most compression underwear is made with moisture-wicking, quick-drying fabric. This helps to reduce salt crystals forming on your skin and causing chafing as you run or exercise. The compression won't be as firm as outerwear, but they are an excellent "support" option to use if you don't need high-grade compression.
Outerwear – Compression outerwear will look like a pair of bike shorts or running tights that cut off at the knees, and they'll be made with the tight fit and compression that you want. However, the material will usually be a bit thicker than underwear, and with a greater durability. This is necessary because the shorts will be exposed to the elements, rub against the seat of your bicycle, and receive more wear and tear than underwear.
Compression outerwear will usually be pricier than underwear. The material will be durable but may not always provide efficient moisture-wicking (you'll use proper sports underwear for that). The fit around the legs will be tight, but you may have more space around the groin area to fit your athletic underwear.
With your outwear compression shorts, you'll want to find a pair of slim-fit athletic underwear made with thinner fabrics. Thick fabrics will increase the risk of bunching underneath the tight-fitting compression shorts. This is one time when it's better to wear briefs rather than boxers or boxer briefs. The high cut of briefs make them perfect for keeping everything comfortable underneath the compression shorts.
Finding the Right Compression Shorts
As with any other item of clothing, you have to know what you're looking for when buying compression shorts. Every brand offers its own unique features, styles, and sizes. It's worth taking the time to shop around to find the right pair of compression shorts.
If you're in the market for great compression shorts, here are a few factors to consider:
Compression – This may sound silly; after all, of course your compression shorts will have compression! Well, remember that Spandex shorts, running shorts, and cycling shorts may all look identical to compression garments. The styles, fabrics, and designs are very similar, but unless the garments actually state that they provide compression, you may walk away with a pair of form-fitting shorts that are more form than function. Always make sure you're buying shorts labeled "compression shorts", rather than just athletic underwear or active tights/leggings!
Compression Grade – The grade of compression is very important to consider. Too firm, and you reduce mobility and potentially impair performance. Too loose, and you don't get the benefits of the compression gear. Endurance athletes (marathon runners, for example) need a higher compression grade (between 15 and 30 mmHg). Resistance trainees, CrossFitters, and joggers can benefit from a lower grade of compression (between 8 and 20 mmHg). The garments will help with endurance and reducing muscle soreness, not enhancing muscular power or strength.
Size – Funny that the size of your compression shorts is the third most important factor to consider! Waist size is obviously important, but you need to think about leg size (both length and fit). If you have large legs, a too-tight elastic leg band can cut off circulation. Inseam length determines where on your thigh the shorts end. Closer to the knee may be better if you have bigger legs.
Materials – Most compression shorts are made with Lycra, Spandex, polyester, and other synthetic materials. These materials offer good elasticity for all grades of compression, as well as better freedom of movement. They're also fairly durable (more so than cotton or wool) and comfortable. Thickness of the material will usually depend on their use (outerwear or underwear).
Moisture-Wicking – As an athlete, chafing is one of your primary reasons for buying athletic shorts and underwear. The material of your compression shorts should be moisture-wicking, as that will pull sweat away from your body and prevent salt crystals from forming on your skin. Quick-drying material isn't as important for underwear, as the moisture-wicking fabric will pull the sweat away from your skin and transfer them to your shorts. However, for outerwear, you may want to consider a material that dries quickly to avoid excessive friction with your skin.
Fit – Like any item of clothing, you need to think about how well the shorts fit you. Some people need more room for their junk to move and breathe, while others prefer everything tight and securely trapped in place. Compression shorts are designed to remain firmly in place, but some will bunch up around the groin if they're not the right fit. This can be highly uncomfortable and often difficult to adjust mid-run/cycle/race.
Compression outerwear may need to be a bit roomier to fit your athletic underwear, while compression underwear can be more form-fitting.
Mobility – Have you ever tried to perform a high-intensity CrossFit or HIIT workout in a too-tight pair of shorts? Mobility is a must if you're going to be doing vigorous activity. Remember that compression garments are meant to enhance endurance, making them a garment primarily useful for marathon and distance runners. They're less useful for CrossFit or workouts that require a lot of lateral/forward/backward movement. You may want to find a pair of shorts with less compression, as that will mean a better range of motion for your exercise.
Use – Compression shorts are designed for a broad range of activities, but there are specific shorts designed with certain sports in mind. For example, compression shorts for cyclists may come with extra padding built into the seat. Shorts for runners may be longer to provide more compression across the entire leg, while compression shorts for ball sports may have a shorter inseam to allow a broader range of motion.
Warmth – Some compression garments are designed to be worn beneath winter athletic apparel, such as snowboarding or skiing clothes. They're not only compression shorts, but they serve as a base layer to keep you warm. The synthetic fabrics are usually effective at keeping heat trapped close to the body, making them an excellent base layer.
Seam – The seams of your compression shorts MUST be designed to reduce chafing. Flat seams prevent the material from rubbing against your legs as you run, preventing friction and irritation. Closely examine the seams of your compression shorts before buying!