Friday, July 29, 2011

Shockwave Therapy on Patellar Tendinopathy a new studay

No Effect of Extracorporeal Shockwave Therapy on Patellar Tendinopathy in Jumping Athletes During the Competitive Season: A Randomized Clinical Trial









Abstract

Background: Patellar tendinopathy is a common overuse injury among jumping athletes. No evidence-based treatment guidelines exist. Extracorporeal shockwave therapy (ESWT) appears to be a promising treatment but its effectiveness has not been studied in athletes with patellar tendinopathy who have symptoms for 3 to 12 months and are still playing.

Purpose: The TOPGAME study was created to determine the effectiveness of ESWT on pain, symptoms, and function in athletes with early symptomatic patellar tendinopathy who are still in training and competition.

Study Design: Randomized controlled trial; Level of evidence, 1.

Methods: Athletes playing volleyball, basketball, or handball with patellar tendinopathy for 3 to 12 months were randomized into the ESWT or placebo group during the first half of the season. The ESWT group received 3 ESWT treatments while the placebo group received sham ESWT. In-season follow-up measurements were 1, 12, and 22 weeks after treatment. The primary outcome was severity of patellar tendinopathy determined with the Victorian Institute of Sport Assessment–Patella (VISA-P) questionnaire. Secondary outcome measures were pain during activities of daily living and sports and after functional knee-loading tests rated on a visual analog scale and subjective improvement. Multilevel analyses were performed to determine differences between groups over time.

Results: Of the 127 symptomatic athletes invited to participate, 62 were eligible, gave consent, and were randomized into the ESWT (n = 31) or placebo group (n = 31). Mean VISA-P scores before and 1, 12, and 22 weeks after treatment were 59.4 (±11.7), 66.8 (±16.2), 66.7 (±17.5), and 70.5 (±18.9) for the ESWT group and 62.4 (±13.4), 66.3 (±19.0), 68.9 (±20.3), and 72.7 (±18.0) for the placebo group. For the VISA-P, there was a significant effect for time (P < .01) but no treatment × time interaction effect (P = .82). The same pattern was seen in visual analog scale pain scores. One week after final treatment, significantly more athletes in the ESWT group reported subjective improvement (65% vs 32%; χ2 = 6.46, P = .01). This was the only difference noted between the 2 groups.

Conclusion: Extracorporeal shockwave therapy as a solitary treatment during the competitive season has no benefit over placebo treatment in the management of actively competing jumping athletes with patellar tendinopathy who have symptoms for less than 12 months.

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Wednesday, July 27, 2011

Flavanol-rich Lychee Fruit Extract Benefits Young Athletes


Flavanol-rich Lychee Fruit Extract Benefits Young Athletes

Keywords:INFLAMMATION, EXERCISE - Flavanols, Antioxidants
Reference:"Supplementation with a Flavanol-rich Lychee Fruit Extract Influences the Inflammatory Status of Young Athletes," Nishizawa M, Hara T, et al, Phytother Res, 2011 Feb 25; [Epub ahead of print]. (Address: Department of Biomedical Sciences, College of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, Japan. E-mail: nishizaw@sk.ritsumei.ac.jp ).
Summary:In a randomized, double-blind, placebo-controlled study involving 20 healthy, male, long-distance runners, supplementation with a flavanol-rich lychee fruit extract was found to be associated with significant improvements in the change in serum interleukin-6 levels between pre- and mid-training, as well as significant improvements in the change in transforming growth factor-beta, pre- and post- a 2-month training. The authors conclude, "These findings suggest that FRLFE supplementation may suppress inflammation or tissue damage caused by high-intensity exercise training."


Wednesday, July 20, 2011

Lactate threshold predicting time-trial performance: impact of heat and acclimation


Lactate threshold predicting time-trial performance: impact of heat and acclimation

The relationship between exercise performance and lactate and ventilatory thresholds under two distinct environmental conditions is unknown. We examined the relationships between six lactate threshold methods (blood- and ventilation-based) and exercise performance in cyclists in hot and cool environments. Twelve cyclists performed a lactate threshold test, a maximal O2 uptake (Vo2max) test, and a 1-h time trial in hot (38°C) and cool (13°C) conditions, before and after heat acclimation.

Eight control subjects completed the same tests before and after 10 days of identical exercise in a cool environment. The highest correlations were observed with the blood-based lactate indexes; however, even the indirect ventilation-based indexes were well correlated with mean power during the time trial. Averaged bias was 15.4 ± 3.6 W higher for the ventilation- than the blood-based measures (P < 0.05). The bias of blood-based measures in the hot condition was increased: the time trial was overestimated by 37.7 ± 3.6 W compared with only 24.1 ± 3.2 W in the cool condition (P < 0.05).

Acclimation had no effect on the bias of the blood-based indexes (P = 0.51) but exacerbated the overestimation by some ventilation-based indexes by an additional 34.5 ± 14.1 W (P < 0.05). Blood-based methods to determine lactate threshold show less bias and smaller variance than ventilation-based methods when predicting time-trial performance in cool environments. Of the blood-based methods, the inflection point between steady-state lactate and rising lactate (INFL) was the best method to predict time-trial performance.

Lastly, in the hot condition, ventilation-based predictions are less accurate after heat acclimation, while blood-based predictions remain valid in both environments after heat acclimation.




Tuesday, July 19, 2011

NFL players starting to develop Brain Injury.



All those hits to the head may have a lasting impact on football players. A new study shows retired NFL players are at a higher risk of developing mild cognitive impairment (MCI), which can be a precursor to Alzheimer's disease.

Individuals with MCI have trouble with memory, language or another mental function. While these problems are often apparent to the patient and others, they are not severe enough to interfere with everyday life.

Researchers screened 513 retired players and their wives with a survey. They found 35 percent of the players had scores suggesting possible MCI. The average age of the players was 61.

"It appears there may be a very high rate of cognitive impairment in these retired football players, compared to the general population in that age range," neuropsychologist Christopher Randolph, Ph.D., was quoted as saying.

A subset of the players was further screened by telephone and underwent a more extensive evaluation at a medical facility. These players were compared to two groups of nonathletes: 41 adults with no cognitive changes and 81 adults with MCI.

The impairments of retired players on neuropsychological tests were very similar to those exhibited by patients with MCI. The retired athletes with MCI were much younger and slightly less impaired overall than the group of nonathletes with MCI.

Previous animal studies have suggested that blows to the head can kill brain cells, even if the hit is not hard enough to cause a concussion. Recent studies have shown the average college football player receives more than 1,000 blows to the head with a magnitude greater than 10 g-force.




Thursday, July 14, 2011

Beetroot Juice containing Nitrate Improves Cycling Economy


Topic:Beetroot Juice containing Nitrate Improves Cycling Economy
Keywords:ATHLETIC PERFORMANCE - Nitrate, Beetroot Juice
Reference:"Acute dietary nitrate supplementation improves cycling time trial performance," Lansley KE, Winyard PG, et al, Med Sci Sports Exerc, 2011 June; 43(6): 1125-31. (Address: Sport and Health Sciences, College of Life and Environmental Sciences, St Luke's Campus, University of Exeter, Exeter, United Kingdom).
Summary:In a randomized, crossover study involving 9 club-level competitive male cyclists, consumption of beetroot juice (0.5 L/d) containing ~ 6.2 mmol nitrate, 2.5 hours before completion of a 4- and 16.1-km cycling time trial was found to be associated with elevations in plasma nitrite and significant increases in mean power output during the 4-km and 16.1-km cycling time trials. Consumption of beetroot juice rich in nitrate was found to improve 4-km performance by 2.8% and 16.1 km performance by 2.7%. The authors state, "These results suggest that acute dietary nitrate supplementation with 0.5 L of BR improves cycling economy, as demonstrated by a higher PO for the same VO2 and enhances both 4- and 16.1-km cycling TT performance."

Wednesday, July 13, 2011

Are Splanchnic Hemodynamics Related to the Development of Gastrointestinal Symptoms in Ironman Triathletes? A Prospective Cohort Study




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Clinical Journal of Sport Medicine:
July 2011 - Volume 21 - Issue 4 - pp 337-343
doi: 10.1097/JSM.0b013e31822148b8
Original Research

Are Splanchnic Hemodynamics Related to the Development of Gastrointestinal Symptoms in Ironman Triathletes? A Prospective Cohort Study

Wright, Helen MBBCh, MPhil*; Collins, Malcolm PhD*†‡; Villiers, Richard De MBBCh, MMed§; Schwellnus, Martin P MBBCh, MSc, MD*‡



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Abstract

Objective: To determine if prerace to postrace changes in superior mesenteric artery (SMA) and coeliac artery hemodynamics were related to the development of gastrointestinal (GI) symptoms during a triathlon.

Design: Prospective cohort study.

Setting: Field study at an international Ironman Triathlon.

Participants: Fifty-nine Ironman triathletes of whom 59% (n = 35) reported GI symptoms (GI group) during the race and 41% (n = 24) remained asymptomatic (CON group).

Assessment of Risk Factors: Prerace questionnaire (personal details, racing and training history, personal general medical history, and medication) and splanchnic hemodynamics.

Main Outcome Measures: Prerace and postrace measurements of splanchnic hemodynamics [artery diameter, systolic velocity, diastolic velocity, and resistive index (RI) of the SMA and coeliac artery] using duplex Doppler ultrasound.

Results: There was a significant decrease in the diameter of the SMA after the race (P = 0.003) and a significant decrease in the RI of the SMA and coeliac artery (P < 0.001) in both the GI and CON groups, but there were no significant differences between the groups. The only significant risk factor for the development of GI symptoms was younger age (P = 0.041). Other risk factors, including high-intensity exercise, poorly trained athlete, and medication use, were not associated with the development of GI symptoms.

Conclusions: The hypothesis that altered blood flow is related to the development of GI symptoms in endurance athletes is not supported by the results of this study. Other mechanisms for GI symptoms associated with endurance exercise should be investigated.




Tuesday, July 12, 2011

The Effect of Pomegranate Juice Supplementation on Strength and Soreness after Eccentric Exercise



Trombold, JR, Reinfeld, AS, Casler, JR, and Coyle, EF.

The effect of pomegranate juice supplementation on strength and soreness after eccentric exercise. J Strength Cond Res 25(7): 1782-1788, 2011—

The purpose of this study was to determine if pomegranate juice supplementation improved the recovery of skeletal muscle strength after eccentric exercise in subjects who routinely performed resistance training. Resistance trained men (n = 17) were randomized into a crossover design with either pomegranate juice or placebo. To produce delayed onset muscle soreness, the subjects performed 3 sets of 20 unilateral eccentric elbow flexion and 6 sets of 10 unilateral eccentric knee extension exercises. Maximal isometric elbow flexion and knee extension strength and muscle soreness measurements were made at baseline and 2, 24, 48, 72, 96, and 168 hours postexercise.

Elbow flexion strength was significantly higher during the 2- to 168-hour period postexercise with pomegranate juice compared with that of placebo (main treatment effect; p = 0.031). Elbow flexor muscle soreness was also significantly reduced with pomegranate juice compared with that of placebo (main treatment effect; p = 0.006) and at 48 and 72 hours postexercise (p = 0.003 and p = 0.038, respectively). Isometric strength and muscle soreness in the knee extensors were not significantly different with pomegranate juice compared with those using placebo.

Supplementation with pomegranate juice attenuates weakness and reduces soreness of the elbow flexor but not of knee extensor muscles. These results indicate a mild, acute ergogenic effect of pomegranate juice in the elbow flexor muscles of resistance trained individuals after eccentric exercise.