Jan 29, 2015Bulletin Board
To Stretch or Not?
In the long-running debate over whether there are benefits to stretching before exercise, compelling new information has been introduced. A study by USA Track and Field (USATF) analyzed data from nearly 1,400 runners and discovered that there was no statistically significant difference in injury risk between those who stretched before running and those who did not.
The study, published on the USATF Web site, involved runners age 13 and up and took place over three months. Runners were assigned to one of two groups: stretchers and non-stretchers. The stretching group was given written and photographic instruction on proper technique and told to complete a three- to five-minute routine that involved stretching their quads, hamstrings, and gastrocnemicus/soleus muscle groups immediately prior to running. Runners assigned to the non-stretching group were instructed to begin their workouts without limbering up.
Over the three months, both groups saw runners suffer injuries that prevented them from running for at least three days at a rate of 16 percent. The rates of injury preventing running for more than a week and more than two weeks were also identical.
The findings were both meaningful and surprising to those involved. “I had gone into this thinking that stretching would prevent injuries,” Dan Pereles, MD, a Washington, D.C.-area orthopaedic surgeon who led the study, told The New York Times. “I was fairly sure of it. Instead, static stretching has no particular benefit.”
Researchers did find that runners who regularly stretched before the study began and were assigned to the non-stretching group had a disproportionately high injury rate. Malachy McHugh, PhD, Director of Research at the Nicholas Institute of Sports Medicine and Athletic Trauma in New York City told the Times that it was likely due to the change in pre-run preparation and is not proof that the stretching itself was beneficial. “Your body adapts to its routine, and if that routine is monotonously habitual as with many runners, it doesn’t take much of a change to cause injury,” he said.
For more information about the USATF study, go to: www.usatf.org/stretchstudy/index.asp.
Cranberry Juice May Stop Staph New research from the Worcester Polytechnic Institute shows that cranberry juice may have previously unidentified bacteria-fighting powers. Cranberry juice has already been shown to help guard against urinary tract infections, but it may also protect against some forms of Staphylococcus aureus.
Researchers had 20 healthy female students drink either 16 ounces of cranberry juice or a placebo, and then provide urine samples after two, eight, 24, and 48 hours. The samples were incubated for 24 hours with strains of E. coli or Staphylococcus aureus, and then tested for the presence of biofilm. Biofilm results when a sufficient number of cells–in this case bacteria–grow together as a colony. The greater the biofilm mass, the more likely there will be an infection.
The samples from participants who drank the cranberry juice had significantly less biofilm formation than those from the control group. “The results we saw with Staphylococcus aureus were dramatic,” says Terri Camesano, PhD, lead author of the study and Professor of Chemical Engineering at WPI. “Essentially, we saw no biofilm growth at all.”
Camesano, who presented the findings at the national meeting of the American Chemical Society in August, says preventing the formation of biofilms is critical because they are a precursor to infection. The biofilms provide a protective environment for the bacteria–one that can be difficult for the immune system to break up. Preventing the formation of the biofilm makes it easier for the body to rid itself of bacteria naturally.
The authors didn’t draw any conclusions as to why cranberry juice is effective against the formation of biofilms, or offer suggestions on whether athletes should increase their consumption. They also don’t know yet if cranberry juice might help in blocking methicillin-resistant Staphylococcus aureus-better known as MRSA. But Camesano says more research is planned.
“Understanding what’s happening with the Staph results is an important new area to examine,” Camesano says. “While I would prefer not to speculate on the reasons behind the results, we are planning to expand our research.”
More Strength Coach Interaction in D-III? At the NCAA Convention in January, Division III members will vote on a proposal that would allow strength coaches to conduct and monitor voluntary off-season workouts for athletes. The proposal was submitted by the Minnesota Intercollegiate Athletic Conference, and Executive Director Daniel McKane says it would allow athletes to improve their performance and reduce their risk of injury.
“Our members feel the off-season is when our athletes really need and want input on how to improve their strength and conditioning,” he says. “Current NCAA Division III rules restrict the level of interaction athletic department personnel can have with athletes during the off-season. We want to provide our athletes the education they’re asking for.
“The rule change should also prevent in-season injuries,” McKane continues. “We know that if athletes are in better shape they’re going to suffer fewer injuries.”
Current Division III rules allow strength and conditioning staff members to observe off-season workouts for safety issues only–they cannot offer coaching advice to athletes. But McKane says he’s not positive all coaches know the rules.
“I think some of them believe strength coaches are allowed to do more than they actually can, so we’re inconsistent across the division,” he says. “Changing the rule would allow for a more consistent interpretation.”
The Division III Student-Athlete Advisory Committee (SAAC) expressed concerns that athletes would feel more pressure to attend voluntary workouts if the proposal passes. “Since the coach can also be the one doing the workouts, there’s more pressure on the student-athletes to participate, even though it is voluntary,” Rowan University SAAC member Brittany Petrella told The NCAA News.
Questions about the proposal can be addressed to Daniel McKane at: [email protected].
The Impact of Impacts
There has been much attention paid recently to the danger of concussions in football. Now, researchers are looking at the effects hard hits can have on other areas of the body, too.
This season, selected members of the NFL’s San Francisco 49ers are wearing pressure sensors inside their equipment, which measure the impact of blocks and tackles. Offensive players have sensors in pads on their chests and abdomen area, while defensive players have them in their shoulder pads. Sensors include wireless transmitters, which send collision information to researchers’ computers on the sideline.
Daniel Garza, MD, an emergency and sports medicine physician at Stanford Hospital and Clinics and the 49ers Medical Director, said in a press release that the aim of the research is to help athletic trainers better understand football-specific injuries. “We’re trying to understand the biomechanics of the trauma players receive, so we can assess how well their body armor is working and what physicians should be looking out for,” he said. “It’s difficult to assess these athletes on the sideline when they’ve potentially sustained some kind of internal injury, especially when they’re reluctant to leave the game.”
Ultimately, researchers hope their findings lead to advances in protective equipment and earlier diagnoses of injuries. Though the project is focusing on the NFL, the findings should help players at any level according to William Maloney, MD, Professor and Chair of Stanford’s Department of Orthopaedic Surgery and a 49ers team physician. “The benefit of [the knowledge] is that we can translate the care of high-level athletes to everyday athletes,” he said in a press release.
