Research in Sport Medicine and Technology

Effect of different intensity warm up on plasma antioxidant enzymes and damage indices of lipid, protein and DNA after intensive activity in non-athlete males

Kazem Khodai

The aim of this research was to study the effect of warm up with two different type intensity on plasma antioxidant enzymes and damage indices of lipid, protein and DNA after intensive activity in non-athlete males. 12 non athlete students of kharazmi University participated in this study. Firist, subjects VO_2peak were measured by Gas analyzer (Meta Max 3B) on the ergometer cycle with incremental test. Work rate in the low and high intensities of warm up were calculated for each subjects on the VO_2peak chart Then subjects in the three sessions with 48 hours interval divided to three groups of warm up with low and high intensity and non-warm. In each session resting blood sampling collected then first group warm up with low intensity (45-50% VO_2peak) for six minutes and then perform intensive activity The Second group performed warm up with high intensity (75-80% VO_2peak) and then intensive activity and third group directly without warm up performed intensive activity. Blood sampling collected after two hours of the intensive activity. In other sessions group members were changed by cross design method. Using analysis of variance with repeated measuring and the LSD test for statistic analyze. The results showed a significant differences in MDA, carbonyl-protein 8-hydroxy-2-deoxy Guanosine and also antioxidant enzymes SOD, CAT and GPX companing to resting state. Main difference of MDA and SOD was not signifacnatly lower in the low intensity warm up state rather than other state. In the other variables non warm up state have lower value and intensity warm up state have higher value. Result of the study indicate that low intensity warm up can decreased lipid damage but not effected on the protein and DNA damage. Also, High intensity warm up can case increases all three type of damage. Therefore low intensity warm up in non-athlete males is better than the high intensity warm up.

Effect of Aquatic and Land–base Plyometric Exercise on Selected Biomechanical Parameters of Butterfly Swimming in Elite Male Adolescent Swimmers10-14 years

Heidar Sadeghi

Introduction and Purpose: The swimming start is very important for achieving better results in
competitions. The Purpose of this study was to compare the effects of two plyometric training techniques
both in aquatic and on land in two start techniques (grab and track) of butterfly swimming in Elite male
adolescent Swimmers.Methodology: 20 elite male swimmers divided into two groups of plyometric
exercises in water and land-based. Swimming performance variables including; anaerobic power of hands
and legs, 25 meter swimming record, The time of contact of head with water and the time of keeping
movement in water, Flying distance from the starting point to the end point of contact with water and the
distance of continuing movement after entering the water using both start techniques, the number of
movements of hands and legs in 13 meters butterfly swimming without start and glide. Data analysis was
performed with MANOVA test. Results: Significant difference was seen in the mean time of contact of head
with water in both start techniques (grab and track) of Butterfly swimming; in addition, there is significant
difference in mean number of hand movement and leg movement in butterfly swimming and the number of
hand and leg movement in full 13 meter butterfly swimming after polymeric exercise in two
groups.Discussion and conclusion: According to the findings of this study, using plyometric training
program led to an increase and improvement in the measured parameters, and use these exercises to
improve start swimming recommended

Effect of Functional Fatigue on Landing Mechanics using Landing Error Scoring System (LESS)

Seyed Hossein Mirkarimpour

One of the factors affecting jump-landing patterns is fatigue. Fatigue is an inevitable component of physical
activity, hence the aim of the present study was to investigate the effect of functional fatigue on landing
mechanics through Landing Error Scoring System (LESS).Fourteen male college students with a mean age of
22±2 years, weight of 68.3±7.2 kg and height of 174±4 were randomly divided into two groups: experimental and
control. Effect of independent variable, fatigue, due to activities resembling athletic training or competition (6-
stations functional fatigue protocol) on dependent variable, landing mechanics, through pre test-post test was
investigated. The independent t-tests and non-parametric U-Mann Whitney test was used for statistical analysis
of data (P < 0.05). The results of the present study indicated the relationship between fatigue and attenuation of
landing mechanics (P=0.02), and therefore an increase in injury risk. Also it was shown that the effect of fatigue
on decreasing knee flexion angle at initial contact was significant (P=0.022). With regard to the results, it can be
concluded that functional fatigue induced by physical activities can alter landing mechanics, and increase loading
of lower extremity joints, particularly the knee. So the risk of injury in these joints may be increased.

Correlation between lower body stiffness and agility in racket-sports athlete

Mojtaba Eshrestaghi

Stiffness is an index for determination of elastic properties of body and its optimum range is different in various
motion patterns. The Spring-mass model is used for calculating stiffness. In this method, the whole leg is modeled
with a linear simple spring. The aim of this study is determination of lower body stiffness and evaluation of its
correlation with agility, as dominant motion pattern in racket sports. 12 national-level male racket-players (age:
25±4 years & weight: 80±7 kg) participated voluntarily in this study. Leg and vertical stiffness were measured
during running on treadmill and hopping test. Pearson’s correlation coefficients were used to examine the
relationships between stiffness and agility test records. Statistical significance was set at P< 0.05. There wasn’t
significant correlation with agility in this study. The reason could be of the contrast influence of knee and ankle
stiffness on performance. This problem requires separate evaluation of joint stiffness.

Compaison the effect of resistance exercise with active and passive rest on aerobic and anaerobic fitness in soccer players

Abbas Keyhanian

The aim of this study was to Compare the effect of resistance training with active and passive rest on aerobic
and anaerobic fitness in soccer players. For this purpose 16 players of Foolad Mobarakeh Sepahan club,
accidentally were divided into rest and active group (Height 177.78±6.68 cm, Weight 64.88±7.97 kg, age
18.22±0.83 years ,and percent fat 20.47±1.8) and rest passive group(Height 178.57±6.99 cm, Weight 64±
6.6kg, age 18±0.81 years ,and percent fat 20.05±1.7). The tests were performed in this order: maximal oxygen
consumption, maximal strength, Tmax, muscular endurance, Hoff and RAST test in the pre and post test. The
exercises were done for 8 weeks and twice week with 10 exercises of 30 to 50 percent of maximal strength
with this difference that the active rest group performed 3 sets of 20 repetitions exercise in 30 seconds that rest
interval between 30 seconds was completed with 2 sets of 10 repetitions exercise in 30 second. The passive
group performed 4 sets of 20 repetitions exercise in 30 seconds that rest interval between 30 seconds was
completed with 3 sets passive rest. After determining the normality by Kolmogorov-Smirnov test and
homogenous variance test, independent and dependent t-tests with a significant level of α ≥ 0.05 were used.
The results indicate that after the training period, a significant difference was found in all variables exceptfatigue index in active rest group. But in passive rest group there were a significant difference in variables AT,
vVo2max, Tmax, performance of Hoff test, bench press muscular endurance and leg press strength from pre
test to post test. The results between groups indicated that there was a significant difference between two
groups in Vo2max, Tmax, AT, vVo2max, leg press muscular endurance, and mean power in benefits of active
rest group. Finally, the results showed that the resistance training with active rest causes improvements in
aerobic and anaerobic fitness of soccer players in comparison to resistance training with passive.

Effect of different walking speed on the gait kinematics of individuals with knee varus

Fariborz Mohammadi Pour

The purpose of current study was to investigate the spatio-temporal gait parameters and knee varus angle
during walking at different speeds in young with knee varus. 18 subjects with varus deformity classified at
grade 3 of bowleg and 17 healthy subjects, volunteered to participate in this study. The following variables
include stance, swing, double support and cycle time, cadence, stride length, angle of varus at the heel
contact, midstance and toe off when walking on the treadmill at speeds of 80, 100 and 120 percent of
preferred walking speed, were measured from using the three-dimensional motion analysis system with six
optoelectronic cameras. The results of between-group tests showed that spatio-temporal gait parameters
in the varus group is similar to the normal group. Also varus angular variables in varus group, was indicate
higher values in comparison to the healthy group, but there were no significant differences. The results of
inter-group tests also showed the knee varus angle generally increases with increasing speed, that none of
the differences were not significant. According to the results, the increase in walking speed will caused to
increase knee varus angle. Therefore, walking with speed less than the normal walking speed, probably is
a suitable solution to reduce the loads exerted on the knee joint and prevention of premature osteoarthritis
in young with knee varus.

Comparison the effects of two pedaling methods on lower limb muscles activity and fatigue index in road cyclists

Mehrdad Anbariyan

The aim of this study was to compare the effects of two pedaling methods on lower limb muscles fatigue
index and muscular activity in road cyclists. For this purpose eight road cyclists participated in two separately
session in laboratory. They were pedaling with pushing technique in first session and circling (pullingpushing)
technique in the other session. Surface electromyography activity of the Rectus Femoris, Vastus
Medialis, Vastus Lateralis, Biceps Femoris, Semitendinosous, Gastrocnemius Medialis, Gastrocnemius
Lateralis and Tibialis Anterior muscles of the subjects were recorded. Each session was performed
according to predetermined protocol until exhaustion. There was a significant difference between pushing
and rest phases during two pedaling techniques with higher muscle activity in pushing technique. Subjects
during circling technique exhausted later. According to the results of this study, the circling technique caused
lower muscle activity consequently, increases gross efficiency. It is recommended that road cyclists utilize
the circling technique.

The effect of six weeks Badminton exercise on the changes of Stress and cortisol level in girls student

Mohammad Ali Samavati Sharif

Introduction and aim: The aim of present study was to assess the effect of six weeks Badminton training
on changes of stress and cortisol levels in non-athletic female students. Materials and Methods: In this
study estimated stress of 120 non-athlete students by stress questionnaire (HAD scale). Were measured
Among subjects who had suffered highest stress, 30 subjects with a mean age of 86/2 ± 22 years, height
56/5 ± 163 cm and weight 95/4 ± 57 kg were selected. Cortisol were measured by the bloodletting. The
subjects were divided into two experimental and control groups as homogeneous. But the control group did
not perform any activity. After training protocol variables were measured again in the same conditions. To
estimate the effect of independent variables on the dependent variable of the t-test and the independent ttest
to compare groups with a significance level (p <0/05) was used. Data were analyzed using spss and
Excel software.
Results: The results of this study showed that doing a six-week badminton practice reduces cortisol levels
(p =0.005), and decreasing stress (p =0.03) in the experimental group.
Conclusion: There was significant change in levels of cortisol and stress in experimental group.