October 13, 2013
Study: Shock-Absorbing Running Shoes Don’t Reduce Injury Risk
[ Watch the Video: Special Running Shoes Don't Always Prevent Injuries ]
redOrbit Staff & Wire Reports – Your Universe OnlineDespite advertising claims that softer soles in shoes can help runners keep from getting hurt, researchers from France and Luxembourg found no evidence suggesting the hardness of a person’s footwear increases or decreases the risk of running-related injuries.
Writing in the British Journal of Sports Medicine, experts from the Luxembourg Public Research Centre for Health’s Sports Medicine Research Laboratory, the Centre Hospitalier de Luxembourg Sports Clinique, and Oxylane Research in Villeneuve d'Ascq, France describe how they conducted a double-blind, randomized, controlled trial probing the impact of a runner’s shoes on their running-related injury (RRI) risk.
They provided nearly 250 runners with standard running shoes possessing either a soft study shoes (soft-SS) midsole or a hard study shoes (hard-SS) midsole. The researchers then tracked those runners for a period of five months, collecting information about their running habits and their injuries via a dedicated online platform.
For the purposes of the study, RRI was defined using two criteria. It had to be any type of first-time pain that was sustained during or directly as a result of running, and it had to cause enough harm that it would prevent a study participant from engaging in his or her regular running activity for at least one day.
According to Reuters reporter Miriam Stix, the study authors found that while factors such as an individual’s body weight and overall fitness level did have an impact on injury rates, the amount of padding in a runner’s shoes did not.
“The results do not support the common argument from the running shoe industry that runners with higher body mass should be recommended shoes with greater shock-absorption characteristics,” lead author Dr. Daniel Theisen, a physical therapist and sports science specialist at the Sports Medicine Research Laboratory, told Stix on Friday.
A runner himself, Dr. Theisen told Reuters he expected that the additional shock-absorption in the footwear would actually help relieve running-related mechanical stress on the physique. However, that was not what he and his colleagues found following their analysis of 247 men and women, all of whom were between the ages of 30 and 50, had body mass index scores ranging from normal to slightly overweight, and ran at least 10 miles each week.
“Participants got shoes provided by ‘a renowned sports equipment manufacturer,’ according to the report, which were customized versions of a model sold in stores,” Stix said. “There were no identifying decorations on the shoes, and all appeared identical except that half of the pairs had a soft midsole - a spongy layer beneath the insole of the shoe's interior.
“The difference in shock absorbing qualities between the shoes with and without the extra cushioning was calculated to be about 15 percent,” she added. “According to Theisen, this was the greatest difference possible while still producing a shoe that looked the same to users. Even the researchers did not know which participants received the softer shoes.”
During the five-month trial period, the runners were asked to train at least once per week and were instructed only to use the shoes they were provided with for the physical activity. A total of 69 runners reported injuries that were counted, and of those cases, 32 runners had been wearing hard-soled shoes while 37 had been wearing softer-soled sneakers.
Dr. Theisen’s team also discovered heavier runners were approximately 13 percent more likely than their normal-weight counterparts to suffer running-related injuries, and that those who had previously been hurt were 75 percent more likely to be injured again. Furthermore, higher-intensity training added 39 percent to an individual’s injury risk, while those with previous running experience were less than half as likely as inexperienced runners to get hurt.