Research in Sport Medicine and Technology

The purpose of this study was to evaluate the effect of eight weeks strength and
plyometric trainings on knee joint position sense. In this study, 45 male students
(21.7±2.17years, weight 69.7±7.89 kg, and height 177.2±5.83cm) volunteered
and selected as subjects to participate in this semi-empirical study. Subjects
divided in three groups include strength (n=15), plyometric (n=15) and control
(n=15). Strength group trained squat, leg flexion and leg extension and
plyometric group trained depth jump, Split squat jump, rim jump and box to box
depth jump. Joint position sense measured at three angles 30, 45 and 60
degrees in knee joint by Biodex Isokenitic system 3. One-way ANOVA was
used for analysis of data. Results of study showed that trainings significantly
improve the joint position sense in initial angel (30degree) on active
reproduction and in initial and final angels (30 and 60 degrees) on passive
reproduction. In addition, comparison of trainings revealed that strength training
in 30 degrees and plyometric training in 30 and 60 degrees significantly improve
the joint position sense. Between two methods of training only on passive
reproduction at 60 degree, significantly difference was observed (p≤0.05).
These protocols can use in rehabilitation to improve proprioception and
neuromuscular coordination.

Background and aims:
In many communities, the sport as a method of therapy is used to improve the
disabled and veterans' health which has been a useful and effective. The aim of
this study was to examine the effect of aerobic exercise on general health and
serotonin levels in inactive veterans. Material and method: Based on semi
experimental design 40 veterans, 25 percent impaired and with age average
40/3±1/4, were selected and randomly divided into two experimental and control
groups. Subjects in the experimental group participated in a period of 12 week’s
aerobic exercise training program, which done 3 times a week at 50-65 percent
of Vo2max. Control group did not participate in any exercise program during
study period. General health of the subjects and its subscales was measured by
the General Health Questionnaire (GHQ). Serotonin levels, VO2max, percent
body fat and BMI before and after training for both groups were measured
respectively. Data were analyzed using t-tests at 5% alpha error level was
performed using SPSS version 16. Results: Data analysis showed significant
difference between the two groups in general health. The difference in
psychosomatic subscales, anxiety and insomnia, social dysfunction and
depression were observed between two groups. Also, the results of this study
showed that after 12 weeks aerobic exercise, percent body fat, BMI and lipid
profile decreased significantly in training group. VO2max and serotonin also
increased significantly compared with the control group (p<0.05). Conclusion:
Aerobic exercise for inactive veterans maybe effective in reducing serotonin
levels and increasing general health and placed in line health promotion
programs.

improves insulin resistance. However, the effect of training sessions a day is not
clear in this regard. The aim of this study was to investigate the effect of one or
two sessions a day of exercise training, with equal intensity and duration, on
insulin resistance in sedentary middle-aged men. Materials & Methods: 30
sedentary middle-aged male volunteers (age=43.6±6.5 yr, weight=80.4±13.6kg,
height=174.1±5.5cm,BMI=26.5±3.6kg/m2،VO2max=35.46±6ml/kg) randomized to
the control (n=10), one session a day (n=10)and two sessions a day training
group( n=10). Exercise program consisted of 16 weeks, five days a week, tread
mill running which was implemented as one (30 minutes) or two sessions (2×15
minutes) a day. Training intensity was 40-50% of HRmax at first week and
reached to 70-80% at 16th week of the training. Measurements of fasting blood
samples (insulin, glucose and adiponectin), insulin resistance, cardiorespiratory
fitness, abdominal obesity and BMI were obtained at baseline and post
exercise. Paired t test and analysis of Variance were used to analyze the data.
Results: After 16 weeks of training, compared with the control group, a
significant reduction in blood glucose, abdominal obesity and BMI, and a
significant increase in cardiorespiratory fitness were observed in the both
experimental groups; whereas insulin resistance remained unchanged, and
adiponectin was significantly increased only in the one session a day training
group. Conclusion: based on the findings it seems that, dividing the physical
activity session in two shorter parts can improve glucose profile, cardiorespiratory
fitness and obesity indicators the same as a continuous exercise session. But in
terms of increased adiponectin and decreased abdominal obesity, continuous
exercise session is more effective.

Abstract
The aim of this study was designing a specific upper body anaerobic power test for wrestlers and determining validity, reliability and objectivity of the designed test. In order to assess the anaerobic power of wrestlers on the basis of upper body Wingate test, Twenty two wrestlers (age=23/40±3/20 year, height=173/13±6/97 cm, weight=74/55±3/88 kg) of Tehran wrestling team (most of them were Asian champion) were participated in this study. Mean, maximum and minimum of anaerobic power and fatigue indices assessed by both tests. In order to analysis the correlation between power indices and physiological indices (blood lactate and heart rate), Pearson correlation has been used, and the differences between blood lactate after 2 min in both tests assessed. The result indicated that there was significant correlation between maximum (p=0/001 r=0/739), mean (p=0/001 r=0/670) and minimum (p=0/01 r=0/650) of power and fatigue indices (p=0/003 r=0/610) obtained by designed test and Wingate test. The result showed that there was significant correlation between heart rate immediately after doing both tests (p=0/001, r=0/705) and also the result show that there was not significant correlation between blood lactate after 2 min. of doing both tests (p=0/07 r=0/353). Statistical analyses also showed no difference between the blood lactate after 2 min of doing both tests. Analyzing the validity of designed test, revealed that there was significant correlation between max (p=0/000 r=0/840), mean (p=0/000 r=0/861) and minimum (p=0/000 r=0/830) power and fatigue indices (p=0/000 r=772) after performing twice of designed test. In analysis objectively of the designed test, the result revealed that there was significant correlation between max (p=0/000 r=0/832), mean (p=0/000 r=0/858) and minimum (p=0/000 r=0/805) power and fatigue indices (p=0/000 r=0/832) which was done by two different tester. It can be concluded that in respect to Wingate upper body test, the designed test in this study is valid and reliable test to measure the anaerobic power of wrestlers.

The purpose of this study was to compare of hip abductor and external rotator
muscles strength between male soccer players with ACl rupture and healthy
male soccer players. 30 male participants (15 soccer players with ACL rupture
as sample group and 15 healthy soccer players as control group) participated in
this study. Hip abductor and external rotator muscles strength tests including
normalized isometric strength of hip abductor and hip external rotator muscles
were evaluated by dynamometer in both groups. Independent t-test was used to
compare datas between two groups.The results showed significant differences
in normalized isometric strength of hip abductor muscles (P=0.003) and hip
external rotator muscles (P=0.127). Regarding the findings of this study, there is
significant difference of hip muscles strength between male soccer players with
ACL rupture and healthy male soccer players .

Introduction and Purpose: The rate of overweight and obesity of childhood is dramatically increasing. It seems that mechanical load would affects motor activities for instance walking pattern. This study undertaken to compare spatio-temporal parameters of walking among overweight and normal childrens 10 to 12 years.
Methodology: In this semi-experimental study, 30 subjects (15 overweight boys and 15 normal boys) are randomly selected participated. Footprints recorded during walking with ink and paper system. In order to make comparison of spatio- temporal parameters of walking of subjects Independent Samples t-Test is used. Results: Significant difference was seen in three parameters spending time, speed and cadence between the two groups; in addition, there is significant difference in foot progressive angle between dominant and non dominant limbs.
Discussion and conclusion: According to the findings of this study, which confirms findings of previous studies, in order to optimize walking pattern perhaps overweight changes the pattern of gait through improvement of motor control.

Balance and strength are important abilities that athletes should have them. This study was designed to investigate the relationship between maximum leg press (non-weight bearing closed kinetic chain) and squat (weight bearing closed kinetic chain) strength with statistic and dynamic balance. Thirty (15 men and 15 women) physically active participants (age, 22.13 ± 1.54 years; height, 171.26 ± 6.92 cm; weight, 66.02 ± 8.27 kg) completed the study. The Biodex Balance System was used to evaluate balance performance. Subjects completed two, 40 seconds trials attempting to maintain their statistic and dynamic balance and Overall Stability Index, Anterior/Posterior Index and Medial/Lateral Index were obtained. Maximum strength also was measured with a 1RM squat and leg press. Significant correlations were found between the measurements of 1RM squat with static anterior-posterior indices (r, 0.019; P=-0.541) and dynamic medial-lateral indices (r, 0.021, P=-0.532) in men and with static anterior-posterior indices (r, 0.016, P=-0.552) and dynamic anterior-posterior indices (r, 0.032; P=-0.491) in women. No significant correlations were found between the measures of 1RM leg press and balance indices in both groups. The results of this study indicate that maximum squat strength has more relation with some indices of static and dynamic balance than maximum leg press.
 

The purpose of this study was to examine the difference between two types of
the soccer instep kick in temporal sequence of motion and muscle
electromyography, during forward swing phase of the kick. Ten elite soccer
players, volunteered as subjects in the study. To culculate the kinematics data,
we used DLT method with two video camera that filmed five markers fixed on
anatomical points of lower body, at 240 fpm. Moreover the electromyography of
rectus femoris, vastus medialis and tibialis anterior were estimated. Kinematic
data from ten players was extracted using image processing toolbox of
MATLAB software. Using these results, we compared sequences of joint motion
and progression of activation muscle in low drive and high drive kick. The
results indicate that there was a difference in ranks of muscle activation
between two kick, but there were no difference in muscles activation time and
sequence of joint motion between low drive and high drive kick. Furthermore
both kicks have a similar proximal-distal pattern and interaction in muscles
contraction and joints motion

The purpose of this study was to survey effects of twelve weeks endurance training on serum levels of selected hormones in underweight men. Eighteen healthy underweight men were randomly divided at two groups: endurance training and control. Serum levels of adiponectin, testosterone, and cortisol were assessed before and after training. Endurance training protocol consisted of twelve weeks pedaling on cycle ergometer (3 sessions per week, intensity 60-70% of reserved heart rate, duration of each session 20-40 min). Data were analyzed by SPSS16 software and using Independent and Paired t-tests. Statistical significance was accepted at P<0.05. Endurance training has no significant effect on serum concentrations of adiponectin (14.4±2.4 vs. 13.9±1.8 &mu;g/ml) and cortisol (178.2±48.7 vs. 167.3±39.6 ng/ml) (p>0.05), while decreased serum testosterone concentration (8.2±1.6 vs. 7.2±1.8 ng/ml) (p=0.032) and increased VO2max index (p=0.008). Performing endurance training twelve weeks has no effect on serum adiponectin concentration in underweight men, likely due to lack of change in body fat percent. It doesn’t appear that decrease of circulating levels of testosterone following this period training has detrimental effects on anabolic-androgenic testosterone-dependent processes, and even according to previous studies, it can be useful for cardiovascular health. Anyway, cardio respiratory fitness level of underweight men improved following the endurance training. It doesn’t appear that endurance training has effect on resting (non-exercise condition) levels of cortisol concentration in underweight men.

Introduction: 24-67% of recreational runners suffer from running-related injuries. The purpose of this study was to test the effect of unstable shoes on selected ground reaction force (GRF) parameters during stance phase of running.
Method: 20 healthy men (age of 21±2.27 years, height of 176.93±5.39 cm, and mass of 72.30±8.84 kg) ran on the force plate placed in the middle of 15 m runway in barefoot, with unstable and control shoe conditions. Peak vertical GRF, posterior force, loading rate and impulsive passive force variables were calculated in the three conditions. A repeated measure of ANOVA and Duncan post-hoc tests applied to test the hypothesis (p<0.05).
Results: vertical loading rate and vertical peak passive force variables were significantly increased in unstable shoe condition compared to control shoes. In addition, peak posterior force and impulsive passive force variables were significantly increased in unstable shoe compared to control shoe.
Conclusion: unstable shoe could increase ground reaction force parameters on foot during running. This finding suggests that unstable shoes could possibly increase risk of running related to injuries.

The aim of the present study was to investigate the effect of glucose and glutamine supplementation on serum HSP72, in non-athlete men during four weeks exhaustive endurance - intermittent training that causes glycogen depletion. For this purpose 20 non-athlete healthy men were selected and randomly divided into four groups including: glucose supplementation with glycogen depletion training group (n = 5, supplement 1), glutamine supplementation with glycogen depletion training group (n = 5, supplement 2), glycogen depletion training group (n = 5, placebo) and a group without any treatment (n = 5, control). The blood samples were collected at the onset of training protocol period and 48 hours after final training session from anticubital venous. Serum HSP72 concentration were determined by ELISA technique. The main and interaction effects of variables were determined using TWO WAY ANOVA compeleted with Tukey post-hoc test. The significant level was chosen as &alpha; = 0.05.The results showed the significant effect of training variable for serum HSP72 concentration, [F(1,17)= 6.362 P<0.05] . The effect of supplementation variable was significant for serum HSP72 concentration, [F(1,17)= 15.362 P<0.01] . Post-hoc test showed the significant difference between placebo with supplement 1 group (p<0.05) and placebo with supplement 2 group (p<0.01). The interaction effect between two variables was not significant. In summery, the results suggested that in glycogen depletion training condition, glucose or glutamine supplementation have significant effect on serum HSP72 concentration.

The purpose of this study was to determine the effect of combination specific resistance and ordinary swimming  training on Breaststroke swimming  performance in young boys. Twenty boys of Alborz  province  swimming team age of 13±1 years ,weight 50/ 65±1/02kg and height 159/8 ±4/91cm, participated in this study. After the initial testing of the performance variable (Fifty-meter record of Breaststroke swimming) , technical variable (stroke number) and  strength variable (strength of spinal extensor muscles), subjects were randomly divided in two groups, Experimental group (combination  specific  resistance and ordinary swimming  training) and control group(ordinary swimming  training).A week of familiarization training was performed to adapt with vest (specific resistance) and then training program were performed  for 6 weeks, three sessions per week .Training program consisted of 15minutes of warmup and 8 repeats of 50 meters breaststroke  with 1minute rest interval between repetitions, in exprimental group (with vest of training) and control group(without vest of training). At the end of the training, post test  was performed  in accordance with the conditions of the pre test.  Kolmogorov –Smirnov  test was used to determine normality of data distribution, Paired t-tests was used to determine within group changes and the covariance analysis was used to compare the progress of dependent variables between the two groups. The results of this study indicated that although swimming performance was significantly improved in both groups (p≤0.05) ,but there were no  significant differences between the groups in fifty-meter record of Breaststroke swimming,­ stroke number and strength of spinal extensor muscles (p≥0.05).It may be attributed to non-professional subjects or Low-intensity resistance training.

Introduction: Taekwondo is one of the most popular martial arts in the world and Iran. Taekwondo is a contact
sport which contains a high rate of injuries. Thus, the more travelling through the time, the more protective
equipments is provided to prevent injuries. The present study purposed to compare the sport injuries of premier
leagues in 2 season and study the effectiveness of protective equipments such as protective gums, particular gloves
and socks, and electronic Hugo in the Iranian taekwondo athletes.
Method: For this prospective study, 197 athletes(with the mean age and body mass of 23.2 year-old and 70.52
kg, respectively) were studied for injuries incurred in 2011-2012 league. Afterward, the collected results were
compared with the results of the same league in 2006-2007, descriptively.
Results: As shown, the injury rate was declined from 69.5 injury per 1000 AE in 2006-2007 league to 19.09 injury
per 1000 AE in 2011-2012 league. All injury types were decreased except epistaxis. Likewise, number of injuries in
upper extremity, lower extremity, head and neck and trunk were decreased.
Discussion: The injury reduction may be due to the application of protective equipments like electronic Hugo which
was a main factor in reducing strikes’ power, and the usage of particular socks and gloves for more coverage and
protection. Additionally protective gums could protect tooth and mandible from injury. Of course the effect of getting
more professional and performing scientific conditioning trainings should not be ignored.

The purpose of this study was to determine the relationship between changes of some of the
cardiorespiratory factors during submaximal activity with slow component of Vo2 after static and dynamic
stretching in 16 active women from physical education college ( Mean ± SD : age, 23.87± 1.62 yr ; weight,
57.20 ± 7.84 kg ; height, 163.46 ± 6.23 cm; body fat % ,23.96 ± 2.70 and Vo2max, 42.15 ± 3.41 ml.kg-1.min-
1). After measurement of Vo2max and LT , the subjects performed two protocols of stretching (static and
dynamic) and one protocol without stretching before submaximal activity (treadmill running at 70% Vo2max)
in three separate sessions. Respiratory gas exchange and HR was measured by gas analyzer and polar
and time constants (&tau;1- &tau;2 - &tau;3) were calculated from O2 kinetics graph. Results revealed a positive correlation
between slow component of Vo2 with changes of VE (0.76), Fb (0.48), Tv (0.67), HR (0.41), &tau;1 (0.49) ,&tau; 2
(0.52) , &tau; 3 (0.46) and steady state oxygen uptake increased significantly after static stretching (P=0.031).
Therefore, results of this study showed that some of changes in slow component of Vo2 after static and
dynamic stretching related to metabolic and cardiorespiratory factors.

Introduction: This research aimed to analyze the effect of 12 weeks aerobic exercise training on some
characteristics of immune system and general health of women with breast cancer. Methods: 40 female
with breast cancer, undertaking chemotherapy, were classified in exercise group with mean age of 36/9±13/2
years, weight of 67/2±9/95 kilograms and body mass index of 21/9±2/9 kg/m2 and control group with mean
age of 38/6±10/1 years, weight of 65/1±8/28 kilograms and body mass index of 21/4±2/1kg/m2. Exercise
group Perfored in 12 contionous weeks walking with moderate intensity (based on Modified-Borg scale and
40-60% Maximum Heart rate)/3 times a week/30-45 minutes in each session. General Health Questionnaire
(GHQ) was used for evaluating general health level. Before and after 4, 8 and 12 weeks CBC DIFF test was
conducted for aim of assessing some characteristics of immune system. CANCOVA was used to determine
the pure effect of exercise intervention. The data were analyzed with significant level of p≤0/05 and by SPSS
16. Results: General health and hope of life was decreased significantly after intervention in control group
(p≤0.05). Number of leukocytes of exercise group was higher after the exercise intervention, but this
difference was not significant, but number of leukocytes of control group was decreased significantly
(p≥0.05). Conclusion: Regular aerobic exercise with moderate intensity is an effective way in maintenance
the number of leukocytes, improving immune system and enhancing levels of general health.

Aims: This study investigated the effects of creatine and L-carnitine supplementation on anaerobic
performance and body weight changes in athletes. Methods: In this single-blind randomized clinical trial, 45
athletes were selected and randomly divided into four groups supplemented with: a) Creatine, b) L-carnitine,
c) Creatine- L- carnitine and D) placebo. The supplementation period was 28 days. Wingate anaerobic test
was done for assessing athletes' anaerobic performance and their weights were measured before and after
the supplementation period. To compare the variables before and after each test, paired t-test and anova
are used compare within and between variables respecdivey. Results: The anaerobic performance indices
in the groups receiving creatine and creatine- L-carnitine were significantly increased after intervention. Body
weights were also significantly increased in the supplemented groups. Conclusions: Based on the dosage
and duration of supplementation in this study, concurrent creatine and L-carnitine supplementation has
positive effects on anaerobic performance. Despite L-carnitine is a weight loss agent, the findings of this
study showed weight gain in the supplemented groups.

The main purpose of the present study was to investigate the kinematics and kinetics of successful versus
unsuccessful basketball free throw shots. Six professional basketball players (age= 23±2.09 years members
of Iranian premier basketball league participat in test. Kinematics of arm motion during basketball free throws
were recorded by two Casio zr200 camera in frequency of 240 Hz. Wilcoxon test was used for significant
differences between successful versus unsuccessful free throws (p ≤ 0/05). Angular velocity of the wrist was
found to be significantly higher in successful versus unsuccessful shots at the time of ball release (p ≤ 0/028).
Wrist (p ≤ 0/008) and shoulder (p ≤ 0/023) joints were found to have significantly more flexion in successful
versus unsuccessful shots while elbow (p ≤ 0/002) remained significantly less flexed in successful shots.
Angular displacement of wrist (p ≤ 0/034) and elbow (p ≤ 0/004) was shown to be significantly greater in
successful versus unsuccessful shots. Integrated EMG of Anterior Deltoid (AD), Triceps Brachii (TB) and
Flexor Carpi Radialis (FCR) muscles was more in successful free throw versus unsuccessful free throw, but
the only significant difference was observed in the Integrated EMG of the Triceps Brachii muscle (p ≤ 0/034).
In summery, increasing the wrist angular velocity and activity of triceps brachii muscle affected successful
free throws.

The purpose of this study was to investigate the effect of eight weeks comprehensive corrective exercises
on upper Crossed syndrome. 40 female college students with forward head, forward shoulder, and kyphosis
voluntarily participated in this study and randomly divided to two experimental group (with mean age
21.60±1.70 years, height 159.78±5.11 cm, and weight 59.04±4.6 kg) and control group (with mean age
21.85±1.87 years, height 160.15±4.32 cm, and weight 58.42±5.76 kg). The experimental groups performed
comprehensive corrective exercises included eight weeks and three times per week. The angles of forward
head and forward shoulder were assessed using photographic taken from lateral view and Kyphosis angle
was assessed using flexible ruler (r=0.93) before and after eight weeks corrective exercises program. The
data was analyzed by SPSS (p≤0.05). On the base of findings, we suggest that experts in order to obtain
better results in their training programs, pay attention to correct abnormalities simultaneously, as a new
approach.

Validation of predicting fatness methods in the Iranian girls with respect to the maturity process could help
to identify anthropometric risk factors. This study evaluate the accuracy of four body composition prediction
equations in the teenager students in Hamadan city .Method: The anthropometry profile of 266 adolescent
girls (12-16 ys) including ,weight (55.69±10.18 kg),body mass index (21.93±3.6 kg/m2) and percent body fat
averages (29.65±4.41%) were measured using the bioelectrical impedance analysis (BIA) as a reference
style and the selected skinfold prediction equations, ie, Durnin-Rahaman, Deurenberg , Westrate-
Deurenberg, Slaugter. Results: Significant relationship was observed between BIA and four body
composition prediction equations (p<0/05) with intervene the maturity level. However the most relationship
was found among BIA method and Durnin-Rahaman logarithmic equation (R=0.82-0.92 ,p<001).
Conclusion: It seems that physical education coaches and health-related organizations for athletic
performance and Clinical assessments of body composition in young individuals probably can accurately
utilized fat prediction, especially by applying the Diurnin- Rahaman skinfold equation.