What is it?
Tight fitting clothing usually worn as an undergarment by serious and casual sportspeople alike. Popular as an injury prevention and recovery aid.
The theory: Based on medical compression garments that use banded, graduated compression to treat a variety of cardio vascular conditions by stimulating blood flow; particularly useful post surgery for inert and immobile patients. For sports people the idea is that compression garments increase blood flow to move lactic acids out of the bloodstream quicker after exercise, aiding recovery, and provide extra support to reduce muscle fatigue and chances of injury. Some manufacturers go as far as suggesting their garments may help treat injuries by providing extra blood flow to the injured area.
The science: While there is some evidence some products may be effective in shifting lactics and reducing muscle soreness, there is little in the way of definitive proof, and many studies are contradictory. A 2011 review of available scientific literature published in respected journal Spotsmed found: "In general, the effects of CGs on indicators of recovery performance remain inconclusive."
The manufacturer: Jamie Hunt, co-founder of Australian CG manufacturer 2XU insists the science behind the company's products is solid. Some studies have produced conflicting results because all CG is not created equally, Hunt says. Some garments are simply tight fitting, rather the providing different bands of compression throughout the garment to shift blood along.
"Most compression garments on the market are in fact not compression, and not graduated," says Hunt. "So if studies are done on these I am sure the results are conflicting. However over 85% percent of research when done to white paper level are positive.
"I would say only a handful of compression companies or those who make compression are truly validating there product. We invest close to half a million dollars a year into research, and have in-house the leading experts on the subject."
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"There is some evidence out there to suggest it reduces post-exercise blood lactate and creatine kinase (an enzyme used as a marker of tissue damage) concentrations with muscle soreness, but whether it is better that other forms of exercise, well you've got to run those sort of experiments to actually establish that," says John Cronin, the director of the Sports Performance Research Institute New Zealand at AUT University. There are also issues around whether garments are fitted correctly and do in fact create graduated compression, says Cronin.
"Most of the garments that are fitted to athletes and based on weight and height, whereas when you go to hospital they measure the girths then you get a garment that is fitted properly with graduated compression."
As for the ability to help heal injuries such as the painful heal complaint plantar faciitis - which some garments are specifically marketed as doing - there is little no evidence to support such claims.
Cameron Palmer, of Auckland Sports Podiatry, says he believes the products don't work. "There are many plantar fasciitis socks that are tight around the arch and they market it as supporting the arch for plantar fasciitis. But there is no science behind it at all."
The athletes: There might not much in the way of solid proof suggesting CG's do much more than make people look cool, but that hasn't bothered sportspeople, many of whom swear by the products. As Cronin puts it: "uptake among athletes is extremely high". Former Warrior Jerome Ropati is a firm believer compression garments were an effective recovery tool. "It feels good. That's all I can say. It feels like it does something."
And if the players like something and believe it works, that's good enough for their trainers. "I am not going to go in and change things that they believe assist their performance regardless if the data is slightly unreliable," says Warriors head of athletic performance Balin Cupples.
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