Jan 29, 2015Bulletin Board
Overfilling the Tank
The optimal hydration of football players during competition is an important part of keeping them on the field and performing at their peak, and a new study shows a majority of NFL teams use hyperhydration on game days. However, it’s unclear how beneficial the practice is, and there are some potential side effects.
A study published in the May issue of the Clinical Journal of Sport Medicine surveyed the head athletic trainers of all 32 NFL teams. Twenty-four teams reported hyperhydrating players, which involves administering IV fluids–in many cases saline–beyond the body’s normal fluid balance. According to the study, an average of five to seven players per team receive about 1.5 liters of fluid two and a half hours before games.
When asked the reasons for hyperhydrating players, 23 teams said it was to prevent muscle cramping. Nineteen teams said they used hyperhydration to ward off dehydration. And 10 teams said it was at the players’ request.
Of those using the technique, 19 felt it was extremely effective or very effective at preventing muscle cramps, and 18 felt the same way about hyperhydration’s ability to stop dehydration. Research, however, does not match the survey respondents’ perceptions. Some studies show hyperhydration to have no effect at all, and Jeff Coombes, PhD, and Simon van Rosendal, PhD, both researchers from the University of Queensland in Australia, were quoted in Medical News Today saying the procedure is “seemingly ineffective and potentially dangerous.” Negative side effects can include blood clots, air embolisms, pulmonary edemas, and peripheral edemas.
Nearly half of NFL athletic trainers using hyperhydration reported seeing complications, the most common being blood clots of the surface veins. NFL Medical Advisor Elliot Pellman, MD, told Medical News Today that “further research on this important topic is needed to gain additional insights into prehydration best practices and care.”
To view the study, “Seventy-Five Percent of National Football League Teams Use Pregame Hyperhydration With Intravenous Fluid,” go to: journals.lww.com and enter the study name into the search window.
Point Person for Supplement Questions
In an effort to help student-athletes navigate the complex world of dietary supplements and banned drugs, the NCAA has added two new provisions to its bylaws on drug testing. It now requires Division I schools to designate a staff member to answer student-athlete questions about the topic and also to educate athletic department staff members who have regular interaction with student-athletes. The new rules went into effect August 1.
Individual schools are given flexibility regarding whom they appoint as their designated responder. According to a press release from the NCAA, the staff member does not need “to posses or develop any particular level of expertise related to NCAA banned drugs or nutritional supplements.” Instead, responders are encouraged to access the Resource Exchange Center (REC), staffed by the NCAA’s third party drug-testing administrator, the National Center for Drug Free Sport. The NCAA considers the REC “the sole authoritative resource for questions about whether the ingredients in nutritional supplements or medications contain NCAA banned substances.”
In terms of educating staff, the NCAA lists three specific areas of required knowledge. Staffers must know that the NCAA maintains an easily accessible list of banned substances, any nutritional supplement may present risks to student-athlete health and eligibility, and questions regarding such drugs should go to the designated responder.
While a main impetus behind the rules is to encourage student-athletes to ask questions about supplement safety, Mary Wilfert, NCAA Associate Director for Health and Safety, stresses that student-athletes may be better off taking a cautious route. “The safest approach for student-athlete health and eligibility would be to avoid the use of unregulated dietary supplements,” she said in a press release. “We encourage institutions to support this approach since there is no way to guarantee purity and safety of any supplement product.”
New Test for Sudden Death
In the ongoing debate over testing student-athletes for heart irregularities in order to curtail sudden cardiac syndrome, two issues arise. The costs of the tests are high and their accuracy in predicting death has recently been questioned.
However, a new screening test may address both concerns. Sami Viskin, PhD, a researcher at Tel Aviv University in Israel, studied the QT interval, which is a portion of the heartbeat, and discovered that individuals with Long QT Syndrome (LQTS) are considered to be at high risk for sudden death. Determining if a person has LQTS is relatively simple if an electrocardiogram (ECG) machine is available.
In the study, published in the Journal of the American College of Cardiology, Viskin compared 68 patients with LQTS to 82 control subjects. Participants underwent an ECG while lying down, then stood up quickly and remained standing while the ECG continued to record. Viskin found that the QT interval in LQTS patients increased significantly upon standing.
“Current screening methods offer no real therapeutic value, because very few people who experience arrhythmias… will ever die from sudden death,” he told Medical News Today. “Moreover, there is such a significant overlap between what is normal and abnormal on an ECG that we need additional screening parameters. This test, when done on people with strong symptoms, can really give us doctors a yardstick to compare those at risk for sudden death syndrome to those who would otherwise go on to a healthy life.”
To view the study, “The Response of the QT Interval to the Brief Tachycardia Provoked by Standing,” go to: content.onlinejacc.org/cgi/content/short/55/18/1955.
Cooling Off on the Need to Warm Up
The requirement to warm up before a competition is something most athletes consider a given. But a new study published in The Journal of Applied Physiology showed that in some cases, a shorter warmup would be more beneficial to athletes.
Study authors Brian MacIntosh, PhD, Professor of Kinesiology at the University of Calgary, and graduate student Elias Tomaras asked cyclists to engage in a traditional warmup: 20 minutes of cycling, with the riders gradually increasing their intensity from 60 percent to 95 percent of their maximal heart rate, then four sprints performed at maximum speed for eight minutes.
The cyclists also completed a lighter warmup, one that involved 15 minutes of cycling at 65 percent of their maximal heart rate and only one sprint. After both warmups, the researchers tested the riders’ leg muscles with electrical stimulation and found that the muscles contracted with more force after the leisurely workout. The riders were also able to perform stronger all-out pedaling for 30 seconds on a stationary bike following the less strenuous warmup.
MacIntosh previously found similar results in a study on the warmups of speed skaters on the Canadian national team, who may warm up for two hours before a race lasting under a minute. MacIntosh determined that the skaters were not contracting their muscles with the same amount of force they had been prior to warming up.
Regarding the cyclists, MacIntosh felt their warmup was more challenging than it needed to be. “This research provides an argument against the traditional, ‘more is better’ warmup concept that is adopted by many competitive athletes,” he told The New York Times.
The abstract of the study, “Less Is More: Standard Warm-up Causes Fatigue and Less Warm-up Permits Greater Cycling Power Output,” can be found at: www.ncbi.nlm.nih.gov/pubmed/21551012.