Asian Journal of Sports Medicine
Volume:5 Issue: 2, Jun 2014

A variety of anthropometric and training characteristics have been identified as predictor variables for race performance in endurance and ultra-endurance athletes. Anthropometric characteristics such as skin-fold thicknesses, body fat, circumferences and length of limbs, body mass, body height, and body mass index were bi-variately related to race performance in endurance athletes such as swimmers in pools and in open water, in road and mountain bike cyclists, and in runners and triathletes over different distances. Additionally, training variables such as volume and speed were also bi-variately associated with race performance. Multi-variate regression analyses including anthropometric and training characteristics reduced the predictor variables mainly to body fat and speed during training units. Further multi-variate regression analyses including additionally the aspects of previous experience such as personal best times showed that mainly previous best time in shorter races were the most important predictors for ultra-endurance race times. Ultra-endurance athletes seemed to prepare differently for their races compared to endurance athletes where ultra-endurance athletes invested more time in training and completed more training kilometers at lower speed compared to endurance athletes. In conclusion, the most important predictor variables for ultra-endurance athletes were a fast personal best time in shorter races, a low body fat and a high speed during training units.

It seems that there is an association between the anterior cruciate ligament (ACL) and stability of the knee. This study aimed to evaluate the balance condition of the injured and non-injured sides of the coper and non-coper ACL-D (deficient) subjects during single and bilateral standing conditions. This case-control study was carried out on 10 coper and 5 non-coper ACL-D knee subjects and 15 sex-age matched healthy subjects. A Zebris platform pedobarograph tool was used in this study. The subjects were tested barefoot during single and bilateral leg stance conditions. The outcome measurements included measurement of the center of pressure (COP) path line length, confidence ellipse area and sway velocity. In double leg stance, data analysis revealed that the COP path line length, confidence ellipse area and sway velocity all showed a significant increase in the injured leg of the non-coper ACL-D subjects when compared to the injured leg of the coper ACL-D and healthy subjects (P=0.002). During single leg stance, all of the parameters showed significant increase in the injured leg of both coper and non-copers of the ACL-D subjects relative to the healthy subjects (P<0.05). This study confirmed a balance deficiency in the injured and apparently healthy leg of the non-coper and coper ACL-D knee subjects. Increased COP path line length, sway velocity and the coinfidence ellipse area clearly showed an impaired body balance. The reduced postural control of the non-coper ACL-D knee subjects in bilateral standing could be more evidence of their poor knee stability status.

To verify whether active recovery (AR) applied after a kickboxing match resulted in better performance in anaerobic tests when compared to passive recovery (PR). Eighteen kickboxers volunteered to participate on a Kickboxing match preceded and followed by anaerobic tests: squat jump (SJ), the counter movement jump (CMJ) and the upper-body Wingate test. Blood lactate (BL), heart rate (HR) and rate of perceived exertion (RPE) were analyzed before and after rounds. The recovery sessions consisted of 10min at 50% of maximal aerobic speed or PR. [BL] was measured at 3, 5 and 10 min after the match, while HR, RPE and anaerobic power were assessed after the recovery period. [BL], HR and RPE increased significantly (P<0.001) during the match. [BL] was lower (P<0.001) after AR compared to PR at 5 min and 10 min (e.g. AR: 8.94 ± 0.31 mmol.l-1, PR: 10.98 ± 0.33 mmol.l-1). However, PR resulted in higher (P<0.05) upper-body mean power (4.65 ± 0.5 W.kg-1) compared to AR (4.09 ± 0.5 W.kg-1), while SJ and CMJ were not affected by the recovery type. The lactate removal was improved with AR when compared with PR, but AR did not improve subsequent performance.

Lipocalin-2 (Lcn2) has been recognized as an adipocyte-derived acute phase protein that is positively correlated with obesity, insulin resistance, type 2 diabetes, and cardiovascular disease. The effects of resistance and endurance training (RT vs. ET) on plasma lipocalin-2 are still unclear. Therefore, the purpose of this study was to examine the effects of RT vs. ET on plasma lipocalin-2 in young men. Twenty nine healthy and sedentary young men (age, 21-29 years) participated in this study. The subjects were randomly assigned to RT group (n=9), ET group (n=10) or control group (n=10). The experimental groups performed either RT or ET, 3 days a week for 8 weeks. The endurance training program included continuous running at an intensity corresponding to 65–80% of maximal heart rate, while resistance training consisted of 2-4 sets of circuit weight training for 8 stations and at an intensity corresponding to 65-80% of 1-RM in each station. No significant changes in the body mass, BMI, body fat percentage and WHR were found after the RT and ET. The results showed that Lcn2 decreased after RT and ET compared with the control group (P<0.05). High sensitivity C-reactive protein (hs-CRP) and insulin resistance determined by HOMA-IR, did not change in the RT and ET compared with the control group. Lcn2 decreases after 8 weeks RT and ET, but this improvement was not accompanied by decreased hs-CRP and insulin resistance in healthy and sedentary young men.

To examine the intra-rater reliability of knee movement data in sagital plane obtained from electrogoniometer (EGM) in a basic, sport-specific task of karate. A total of 23 elite karate athletes (13 females and 10 males; mean age of 16.10±1.26 yrs) participated in this study. The task was defined as performing three consecutive Zenkutsu-dachi in two sessions. The used EGM was a twin axis of Biometrics company. EGM curves were plotted in MATLAB software separately. The indices of three points in the plots corresponding to extremes of flexion and extension of knee in the first dachi were determined. There was also another (forth) point which was not in extremes of movement. As it was repeated in all curves, it was perceived as a biomechanical event and was assessed. The phases of movement between the points were scaled between 0 to 100% of activity. Repeatability of the forth point index was assessed by intraclass correlation method. Intraclass correlation of the ratio in the first testing session was 0.666 and in second was 0.448. The interval between points were considered as phases of movement. After determining three phases of dachi, it was shown that these phases pertained a specific ratio of the total plot which were 48%, 36% and 16% of total respectively. Dachi could be divided into three distinct phases; each of them should constitute a specific percent of the total in an elite athlete.

This study was conducted to assess the effect of Two-week L-carnitine supplementation on known markers of oxidative stress and muscle damage following acute bouts of exercise in active healthy young men. Twenty-one active healthy men volunteered for this study. Participants were randomized in a double-blind placebo-controlled fashion into two groups: L-carnitine (C group; n=10) and placebo group (P group; n=11). They arrived at the laboratory after overnight fasting. A baseline blood sample was taken. Afterwards, subjects consumed either L-carnitine (2 capsules containing totally 2000 mg L-carnitine) or placebo (2 capsules containing totally 2000 mg lactose) daily for 14 days. On the day of the test, participants attended the athletics arena after overnight fasting. Then, participants were asked to run 14 km on the track at their highest ability. Blood samples were taken immediately, 2, and 24 hour after exercise. Plasma total antioxidant capacity (TAC), MDA as thiobarbituric acid-reactive substance (TBARS) as a marker of lipid peroxidation, creatine kinase (CK) and lactate dehydrogenase (LDH) as markers of muscle damage were measured. TAC increased significantly 14 days after supplementation and 24h after exercise in C group compared with P group (P<0.05). Serum MDA-TBARS, CK, and LDH were significantly lower 24h after exercise in C group compared with P group (P<0.05). Serum MDA-TBARS, CK, and LDH were significantly lower 24h after exercise in C group compared with P group (P<0.05). These results suggest that two-week daily oral supplementation of L-carnitine has alleviating effects on lipid peroxidation and muscle damage markers following an acute bout of exercise in active healthy young men.

Rupture of pectoralis major (PM) occurs most commonly as a result of an indirect mechanism associated with extensive tension on a maximally contracted muscle. Patients with PM tendon ruptures, classically present a history of sudden severe pain in arm and shoulder at the time of injury. Treatment options vary from conservative to operative. In cases with total or near-total injuries, surgical treatment by anatomic repair is generally advised, since conservative treatment may lead to poor results. The present paper reports 24 cases of surgically-treated ruptured PM while assessing the results. Between 2005 and 2010, 32 cases of unilaterally distal ruptured PM were surgically treated by the same surgeon and same technique, in two teaching hospitals of Tehran University of Medical Sciences. All cases were followed postoperatively by physical examination and functional criteria. Since eight of the cases were lost from follow up, 24 cases were followed for at least one year. According to modified Kakwani system, 6 of our patients (25%) rated as excellent, 15 cases (62.5%) rated as good, 2 cases (8.33%) rated as fair and 1 case (4.1%) rated as poor. In conclusion, we see that 87.5% of the patients had good to excellent results, according to modified Kakwani classification, after one year of follow up. So it seems that surgical repair of the pectoralis major ruptures will help the patients to return to their previous activities more frequently and we believe, to achieve better functional outcome. Meticulous surgical technique and attention to rehabilitation program are more important than delay in surgery.

Exertional heat stroke (EHS) is still a main cause of death in sport. Many of EHS complications could have been prevented if EHS had been recognized and treated early and properly. We report an unusual case of multiple organ failure caused by EHS due to intensive sportive activities in a hot environment with lack of primary care. A 35-year-old healthy sportive man was admitted in our hospital because of muscle aches and weakness as well as dark urine three days after a six hour marathon run (Agadir Semi-Marathon) in a very sunny day. Patient developed rhabdomyolysis, acute renal failure (ARF) requiring hemodialysis because of hyperkaliémia, azotémia and severe metabolic acidosis, disseminated intravascular coagulation and acute liver failure. Unfortunately, after eight days of intensive care, the patient died from septic shock and multiple organ failure. This case reminds us that, despite the advancements of knowledge in the area of EHS prevention, recognition, and treatment, knowledge has not been translated into practice.