In most cases warming up before exercise is good, Published Jan. 11, 2013 By Mike W. Ray Tinker Public Affairs TINKER AIR FORCE BASE, Okla. -- Scientific research provides conclusive evidence that Airmen preparing for vigorous exercise such as the 1.5-mile run in their annual fitness test would perform better if they did not "warm up" with static stretching. The study was performed by retired Chief Master Sgt. Ralph Humphrey. The chief worked in the Tinker AFB Fitness Assessment Cell during the two years civilians directed the testing. "This is where I saw the preparation problem for the 1.5-mile run test and wanted to help make a change," he said. Humphrey retired from the Air Force in 2009 after a career that spanned more than 30 years, and now is the Air Force Junior ROTC Instructor at Carl Albert High School. In collaboration with the Air Force Research Lab, Humphrey performed a study at Tinker AFB on "The Negative Effects of Static Stretching on Sprint Repeats." The study was performed using volunteer Airmen. "A persistent misunderstanding across Air Force physical fitness activities and education is the belief that static stretching has a beneficial effect on athletic performance," Humphrey wrote in his final report. His study provided "statistically significant" evidence that static stretching before the 30-meter sprint repeats resulted in slower times "when compared to the no-static stretching sprint repeat times..." "Simply put, the muscles become compliant and are less efficient when put into service, hence reduced performance," he explained. The study "cast a broad impact beyond elite athletes into the arena of Airmen, a first of its kind military study," he wrote. Airmen are known to use static stretching as a form of preparation directly prior to their 1.5-mile fitness assessment run, Humphrey related. Although static stretching is widely accepted as "an essential component of the warm-up," research data indicates otherwise, he noted. His study subjects were 25 active-duty Airmen (18 men and seven women) who are required to take an annual Air Force physical fitness assessment test that includes cardio and strength elements. The volunteers ranged in age from 18 to 30 and had scored satisfactory or excellent on their most recent fitness assessment test. Stretching before sprinting had a negative effect on the Airmen's performance, Humphrey concluded Other researchers suggest that "mechanical mechanism, a neurological mechanism, or a combination of the two, could be responsible" for the longer sprint performance times after a static stretching protocol, he said. "The static stretching protocol increased muscle compliance, potentially slowing contraction and neural response time," he continued. "This study suggests static stretching reduces optimal stretching-shortening cycle performance and creates electromechanical delay." "Use of the term 'prepare-to-move' in lieu of stretching or warm-up is an alternate preparation instruction to change deleterious static stretching behavior in fitness preparation," Humphrey advised. Humphrey said the academic background research on his study was completed during the last half of 2010. "During early 2011 I worked the approval process through the Air Force Research Lab" and recruited the 25 volunteers. The subject testing was performed from November 2011 through February 2012. The test subjects completed two entire cycles (four test dates) to reduce any variables from just one comparison, Humphrey said. Each subject was required to complete a training day followed by four testing dates that completed two rounds of static stretching and no static stretching, he said. "My biggest problem was weather and wind, to make sure this variable was minimized." Data analysis and final research reported were submitted to the Air Force Research Lab "around the July 2012 time frame," he said. The AFRL officially closed out the study in August 2012.