Jan 29, 2015Bulletin Board
Nitrate for Increased Muscle Power?
Spinach, beetroot, and other leafy green vegetables like lettuce and chard are not just full of vitamins. They are also rich in nitrate, which, according to a study published in the August issue of The Journal of Physiology, may help boost muscle strength.
Researchers from the Karolinska Institute in Sweden divided mice into two groups. One received nitrate in its drinking water for a week while the other did not. The scientists discovered that the mice given the nitrate had stronger leg and foot muscles when the seven days were up. They believe the strength came from higher concentrations of the nitrate proteins CASQ1 and DHPR, which are involved in the homeostasis of calcium, an important factor in muscle contraction.
The amount of nitrate given to the mice was equivalent to what a human would get from eating 200 to 300 grams of spinach or two to three beetroots per day. “From a nutritional perspective our study is interesting because the amount of nitrate that affected muscle strength in mice was relatively low,” lead researcher Andres Hernandez, PhD, said in a press release. “Translated to humans it means that we can obtain the equivalent volume by eating more of a vegetarian diet, as nitrate is found naturally in several leafy vegetables.”
To view the abstract of the study, “Dietary nitrate increases tetanic and contractile force in mouse fast-twitch muscle,” go to: www.ncbi.com.nlm.gov/pubmed and search the study title.
Identifying Risk Factors for Ankle Sprains
While ankle sprains are a common and often nagging injury for soccer players, very little soccer-specific research exists to explain why certain players experience them while others don’t. But a study published in the American Journal of Sports Medicine may have pinpointed a cause: unequal ankle strength.
Researchers from the University of Athens tested the ankle strength and stability of 100 soccer players from four Greek professional teams prior to the start of the season. Specifically, they looked at potential risk factors for non-contact ankle sprains, including somatometric asymmetries, previous injuries, lateral dominance traits, and ankle joint asymmetries in isokinetic muscle strength, flexibility, proprioception, and stability. After the tests, the players were monitored over the 10-month season.
During that time, 17 players suffered at least one non-contact ankle sprain. When researchers looked back at their preseason test results, they discovered that athletes who had one ankle significantly stronger than the other were nine times more likely to suffer a sprain than players with similar ankle strengths. As a result, researchers recommend that athletes’ ankles be evaluated in the preseason, noting that doing so may “improve prevention strategies for this type of injury in soccer.”
To view the abstract of the study, “Intrinsic risk factors of noncontact ankle sprains in soccer: a prospective study on 100 professional players,” go to: www.ncbi.com.nlm.gov/pubmed and search the study title.
Track and Field Injuries On the Rise
A recent study shows a drastic rise in the number of injuries affecting young athletes competing in track and field. An article published in the May issue of The Physician and Sportsmedicine showed a 36 percent increase in youth track and field injuries that required a trip to the emergency room between 1991 and 2008.
Researchers from the Center for Injury Research and Policy of The Research Institute at Nationwide Children’s Hospital in Cincinnati used data from the United States Consumer Product Safety Commission, and studied the records of children between 10 and 18 years old. The most common injuries were sprains and strains, which comprised 52 percent of reported injuries, followed by fractures and dislocations at 17 percent. The ankle and knee were the two most commonly injured body parts at 21 and 16 percent, respectively. Researchers found certain injuries were more prevalent in some events than others. Cross country running led to the most lower-leg injuries, while sprinting was four times more likely to cause a pelvis injury and three times more likely to cause an injury to the upper leg. Hurdling triggered the most upper extremity injuries. Additionally, the data varied by age group, with high school students more likely to suffer lower leg injuries, and elementary school students more likely to have an upper extremity issue.
“Participation in track is a great way to encourage children and adolescents to remain physically active,” Lara McKenzie, PhD, Principal Investigator at the Center for Injury Research and Policy and senior author of the study, told Science Daily. “However, the increase in injuries corresponding with the increased participation in this activity suggests we need to do a better job of preventing track-related injuries among our young athletes.”
The full text of the study, “Track-related injuries in children and adolescents treated in US emergency departments from 1991 through 2008,” can be found by going to: www.physsportsmed.org and searching the study title.
Teaching Checking Earlier Not the Answer
A series of high profile injuries caused by bodychecking in ice hockey, including two instances where players were paralyzed, have attracted an unflattering spotlight on the safety of the sport. Some believe that safety lies in teaching players how to check properly earlier in their careers. However, a study published in the June issue of the Clinical Journal of Sport Medicine casts doubt on that theory.
Researchers from the University of Alberta studied emergency room records of nearly 8,000 players ages 9 to 15 who played at three different levels of youth hockey. Records from those athletes who played from 1997 to 2002, before a rule change that lowered the age at which players were taught to check, were compared to those of young athletes who played after the rule change. Researchers found an overall reduced injury rate in the age group affected by the rule change, but no significant differences in the number of fractures, head injuries, or neck injuries. There was also no significant change in injuries experienced at older ages by players who were exposed to checking at a younger age.
Donald Voaklander, Director of the Alberta Centre for Injury Control and Research, told Science Daily that the results show there is little benefit to having players check at a younger age. “It really does not have much merit,” he said. “Exposing 11- and 12-year-olds to bodychecking is not helping matters, so there is no point in continuing it.”
The abstract of the study, “Hockey-related emergency department visits after a change in minor hockey age groups,” can be found by going to: www.ncbi.com.nlm.gov/pubmed and searching the study title.