نشریه مطالعات کاربردی علوم زیستی در ورزش
پیاپی 4 (پاییز و زمستان 1393)

Bachground and Low back pain is one of the most common health problems in communications across the world, especially in industrialized countries; hence it would be necessary to find some ways to prevent and treat the low back pain. The aim of this study was to investigate the effect of core stabilization exercises on disability and abdominal and back muscle strength in patients with chronic low back pain caused by disc herniation. 30 male and female patients with chronic low back pain caused referred to physical therapy clinics purposefully selected and randomly were divided into two groups as experimental and control. The experimental group was received core stabilization exercises and conventional treatment; but the control group received only conventional treatment for 8-weeks. The Oswestry questionnaire was used to assess the variables of disability, moreover, the Straight leg raising test for abdominal muscle strength and dynamometer test for back muscle strength also were used. Analysis of covariance was used to test data and the significance level was considered as p≤0.05. The result indicated that 8-weeks of core stabilization exercises significantly reduced the disability (p=0.001). Moreover, increase in abdominal muscle strength (p=0.001) and back muscles strength were significantly higher (p 0.001) in the experimental group as compared to the control group. Prescribing core stabilization exercises by taking the necessary precautions, can be effective to reduce disability and improving muscle strength in patients with chronic low back pain caused by disc herniation.

Down syndrome is consider as the most common genetic disorders to mental disabilities. There are specific anatomical and physiological characteristics in Down syndrome (DS) people that make them different from other healthy people. The aim of this study was to identify the relationship between postural control and structural profiles in children with Down syndrome. 30 male with DS (mean age: 14/86 ±1/65 yr., height: 158/89 ±10/1 cm, weight: 63/33±13/9 kg, body mass index: 25/50±4/19 kg/m2) and 25 patient healthy peers (mean age: 15/04 ±2/13 Yr., height: 164/36 ± 11/42 cm, weight: 56/24±12/01 kg, and body mass index: 20/72± 3/58 kg/m2) participated in this study as the sample group. The head and shoulders postures, lordosis and kyphosis angles and balance were evaluted with the photography, flexible ruler and Biodex balance system respectively. Independent t-test and Pearson correlation coefficients were used to analyze the data (p≤0/05). The results indicated that the forward head posture (p=0.001) and balance (p=0.001) of Down syndrome patients are significantly lower but the kyphosis angle of them is significantly higher (p=0.001) than healthy participants. Moreover, the significant relationship were found between the forward head posture and anterior-posterior balance test (p=0.02), and between the kyphosis with anterior-posterior balance (p=0.009) and finally between the kyphosis with general balance (p=0.006) in individuals with Down syndrome. Therefor due to poor balance and some structural abnormalities in patients with Down syndrome, it seems that the corrective exercise would be necessary to improve balance and postures in individuals with Down syndrome.

According to the influence of muscle fatigue on postural control, it is necessary to assess the recycling balance in improving performance in different age groups. The purpose of this study was to identify the effect of dynamic balance training during active recovery on regaining of active equilibrium in exhausted athlete. 30 trained healthy men students (mean age: 21.3 + 1.66 yr. weight: 64.03 +7.47 kg. height: 177.43+1.73 cm) volunteered for this study and randomly divided into two groups. Y balance test was used to assess of dynamic balance and Susco protocol in 7 stations with rate of perceived exertion (RPE) was used to assess the fatigue. The dynamic balance training were included as walk on the straight line, stork balance test, stand on forepaw when they are moving, and hip and jump balance test. For statistical analysis the dependent and independent t test, ANOVA and scheffe were used and significant level was considered if p ≤ 0.05. In the YBT test, the balance significantly increased (p<0.001) in the active recovery group. The recovery of balance was significantly higher (p<0.001) in the exercised balance individuals than non-exercised balance individuals during active recovery. In addition, postural control after performing of exhausted protocol reduced (p≤0.05) in whole directions and in the pre-, mid-, and post-test of RPE. Concerning the impact of balance on the quality of exercise skills, trying to recycle the balance between the high intensity exercises can lead to improving of exercise mistakes after fatigue, and this may result in better performance in competitions.

The physical fitness, form and the anatomy of the athletes have a significant role for their succession; therefore the present research aimed to describe the anthropometric and physical fitness profile of the Iranian’s national field hockey players. 29 players in the Iranian’s national team camp took part in the research voluntarily, with average age of 23.42±3.61 yr., height of 176.8±7.17 cm, weight of 71.62±8.32 kg. This group of players were consisted of four different positions; 4 goalkeepers, 10 defenders, 10 midfielders, and 5 strikers. The anthropometric characteristics including weight, BMI, sitting height, the arms’ length were measured by standard methods. Moreover, the physical fitness factors also were measured by following tests: 36 meters shuttle run, Illinois test, 10 × 20 meter, standing long jump, bending forward, 1600 meters, sit and reach, and Zig Zag jumps test. The statistical analysis was calculated using SPSS v.20 and MS Excel, through which the anthropometric and the physical fitness profile of the players in each position. The BMI of other characteristics of the goalkeepers, defenders, midfielders, and strikers are as follow respectively; 23.11±2.41 kg/m2, 23.11±1.6 kg/m2, 23.21±1.7 kg/m2, 21.71±1 kg/m2; the sitting height 94±4.71 cm, 94.21±5.11 cm, 93.51±4.91 cm, 97.21±3.51 cm; the arms’ length 181.23±6.11 cm, 180.44±8.63 cm, 177.74±8.06 cm, 185.43±7.65 cm; the speed 5.29±0.28 sec, 5.02±0.11 sec, 4.99±0.22 sec, 5.11±0.09 sec; the agility 15.85±0.53 sec, 17.04±0.77 sec, 15.2±0.41 sec, 15.42±0.93 sec; the speed endurance 44.37±0.8 sec, 48.73±1.66 sec, 43.86±0.75 sec, 43.59±0.73 sec; the lower limb power 240.2±15.53 cm, 245.43±14.13 cm, 245.33±16.53 cm, 249.48±9.43 cm; the flexibility 36±5.93 cm, 35.58±5.43 cm, 32.61±7.70 cm, 27.42±10.82 cm; the cardiovascular endurance 392 sec, 357 sec, 342±0.02 sec, 368±0.02 sec; the abdominal muscles endurance 63.76±6.21 no, 61.78±4.35 no, 57.68±4.59 no 56.49±4.84 no; and the lower limb muscles endurance 136.79±10.65 no, 140.32±13.60 no, 142.52±5.50 no, 140.60±10.90 no. The anthropometric characteristics of the Iranian players holding different positions are at favorable level, although they have weaknesses regarding most of the physical fitness parameters.

Wingate test involves a 30 seconds maximal exercise on cycling ergometer while the load is selected according to the body weight. Beside the body weight, the load is also related to other parameters such as age and gender. Also other parameters such as level of fitness, body mass index smoking of the exercisers can be affecting in the load selection for the test. This study suggests an intelligent load selection method for Wingate test using artificial neural networks according to all the affective variables. In this study 30 male students of Isfahan university volunteered to perform Wingate anaerobic power test on cycling ergometer (Monark 894). Moreover, the Rapid miner software was used for prediction of optimal workload according to characteristic of subjects. According to the data mining algorithms, the Height, weight, age, exercise, pelvic fat and abdominal fat indicated the greatest impact on prediction of optimal workload. According to the results, neural network was able to predict the amount of load for both train and test data with %93 and %90 confidence limits, respectively. This network can be used to delicately determine the load for anyone.

The purpose of this study was to investigate the effect of caffeine on muscle strength and endurance in amateur soccer players. The research method was quasi experimental and population research was selected of soccer players leagues of Saveh in 2012. Forty eight athletes were selected (mean BMI= 23.8 ± 0.36 kg/m2, weight= 76.1 ± 1.22 kg, height= 178.5 ± 0.89 cm and age= 24.8 ± 0.49 yr.) and randomly divided into two experimental and control groups. After measuring body mass index, the muscle strength and endurance also were evaluated with one-repetition maximum (1RM) test in leg press and 80% 1RM repetitions, respectively. 72 hours later, the experimental and control groups consumed caffeine (5 mg/kg) and placebo (Flour) respectively. The same measurements of pre-test session were repeated one hour after supplement consuming. Independent t-test was used to compare the differences between groups and significance level was set as p˂0.05. The results showed that there was significant increase in strength (p<0.0001) and endurance (p<0.04) in the caffeine group; but there were no any significant changes in placebo individuals (p˃0.05). Findings show that consumption of 5 mg/kg caffeine significantly improved muscular strength and endurance in the amateur soccer players.

Nowadays despite the world minded against the use of steroids, unfortunately the use of these drugs is increased by athletes. The purpose of this study was to identify the amount of prevalence awareness and complications of anabolic steroids in male athletes. This study was a cross-sectional study in the city of Mashhad and included bodybuilding athletes. A questionnaire with 19 questions whose validity that already confirmed by 13 doping experts was used. Moreover, the reliability of the questionnaire was calculated through evaluation of the collected data from 30 participants and measuring the Cronbach›s alpha (α=0.80). The questionnaires were then distributed among 300 male athletes from eleven clubs that were randomly chosen as a cluster method. To analyze the data descriptive statistics (frequency, percentage, mean) and independent t-test were used. The results indicated about of 64% of athletes were used from steroid drugs. Data also indicated that there was a significant correlation between the history of the championship with the prevalence of drug use (p <0 /001) and the level of awareness (p < 0/003). Moreover, 86.9 percent of the participants believed that consuming of steroieds is necessary to win in sport events and 47 percent of them began the use of these drugs in the first year of their sport engagement. It seems that coaches and athletes haven’t enough knowledge about the affects of the steroids in the body, so they use a lot of these kind of drug. Therefore it is necessary to make comprehensive and educational course to improve the knowledge of athletes and coaches.

Many studies show that there is close relationship between health and cardiovascular endurance indices so that regular exercises can improve these indices. The main purpose of this research was to examine the effect of eight weeks of aerobic exercise training on physiological parameters as cardiovascular endurance and body composition of high school boy students aged 15 to 18 in Kashan during 2012-2011. This stud considered as a quasi-empirical research including high school student boys in Kashan. Thirty students out of 120 were selected randomly and further divided into two equal groups including the experimental group (mean age 1.30±17.46 yr., weight 9.91±56.73 kg, height 4.92±168.73 cm, BMI 3.42±19.88 kg/m2) and the control group (mean age 1.18±17.53 yr., weight 11.96±60.06 kg, height 7.84±169.66 cm, BMI 3.51±20.79 kg/m2) respectively. Variables including maximum oxygen consumption, resting heart rate and body composition were measured. The exercise program included eight-weeks of aerobic exercise, three times per week, performed at 60 to 70 percent of maximum heart rate. During the protocol, the control group had no sport activity. For statistical analysis, the Kolmogrov-Smirinov normality test along with covariance analysis and Leven tests were used. The result showed that aerobic exercise significantly improved cardiovascular endurance (increased maximum oxygen consumption, p=0.001, decreased the resting heart rate (p=0.0001), but had no significant effect on body composition (p=0.86(, body fat percent (p=0.16) and ideal body fat (p=0.31). No significant difference was observed in the control group (p≥ 0.05). Eight weeks of aerobic exercise up to %70-%60 of maximal heart rate improved cardiovascular endurance indices. Moreover, no significant changes in the body fat of the participants were observed and this may be due to normal body composition. More research on fatty people are necessary for better understanding of the issue.