فصلنامه علوم زیستی ورزشی
پیاپی 21 (تابستان 1393)

The aim of the present study was to examine the effect of menstrual cycle on substrate metabolism، energy expenditure and performance during exhaustive incremental exercise in female students. For this purpose، 15 female students (mean age 21. 17 ± 1. 47 years، BMI 20. 55 ± 1. 71 kg/m2) participated voluntarily in this study. The design was adjusted in three stages: bleeding، follicular and the late luteal of the menstrual cycle. Exercise protocol was incremental until exhaustion. Subjects'' oxygen and dioxide carbon in their respiration was collected and analyzed 30 minutes before the exercise in lying position (base)، during incremental protocol until exhaustion and one hour after the exercise in lying position as EPOC. Fat oxidation، carbohydrate and energy expenditure was measured by indirect calorimetry. To analyze data، descriptive statistics and ANOVA with repeated measures were used. The results showed no significant difference in energy expenditure، performance، fat and carbohydrate oxidation in different stages of the menstrual cycle (bleeding، follicular and luteal) during exhaustive incremental exercise. In the incremental exercise، consumed calorie and carbohydrate and fat oxidation had no dramatic difference in the bleeding stage، early follicular and late luteal probably due to the lack of a dramatic difference between estrogen and progesterone concentrations in young girls.

It is generally believed that unaccustomed exercise causes myofibrillar damage. In recent years، cold water immersion (CWI) following heavy training sessions and matches has been common aiming at reducing soreness. However، there is no strong scientific rationality if this method really accelerates recovery after exercise. In addition، there is a question that if it is possible for this method to interfere in short-term adaptations resulted from exercise. HSP25، as one of the stress proteins that has been shown to play an important role in the remodeling process of recovery after damaging exercise، was discussed in this study. The aim of this study was to investigate the expression of HSP25 protein following cold water immersion after damaging exercise in different recovery time courses. 96 male Wistar rats (weight 290±10 gr and age 8-9 weeks old) were divided into two groups of exercise (Ex) and exercise followed by cold water immersion (Ex+CWI). Each group was divided into 6 subgroups in different time courses before and after the exercise (before، 0. 5، 24، 48، 72، and 168 hours after the exercise). The exercise protocol consisted of 45 minutes of running in a treadmill with incline (speed: 20 m/min. and incline: -17 degrees) and the cold water protocol consisted of 10 minutes of immersion in 10̊ water. The HSP25 protein of skeletal soleus was measured by ELISA method in different time courses. Analysis of variance was used to analyze the data within a group while independent t test was sued to compare the data among the groups in different time courses. The significance level was considered 0. 05. It was observed that the HSP25 protein increased significantly in all time courses except for 168 hours after the exercise (P<0. 05). However، in Ex group، HSP25 level reached its peak level 48 hours after the exercise while the peak time course for Ex+CWI group was 72 hours after the exercise. The most important finding of this study was that CWI delayed the expression of HSP25 protein of skeletal muscle. These findings indirectly indicated that cold water immersion after exercise can increase the response of skeletal muscle to exercise-induced muscle damage and delay the recovery periods.

Superset exercise is a mode of strength training characterized by limited rest intervals between sets. Our Study aims to investigate plasma CK، IGF-I، and GH responses to reverse and compound supersets. Fourteen trained men (BMI= 23. 25±2. 59; Age= 24±2. 32) participated in our study. Subjects were designated to two groups of 7 each، and a cross design was used in exercise performance. Exercises were performed in two modes of compound and reverse supersets (including consecutively exercising agonists in compound mode، and exercising agonists and antagonists in reverse mode، for both upper and lower body) at 10-RM and blood samples were obtained immediately. Independent t test was used for data analysis and it was found that only CK values were significantly different (P = 0. 006) between two modes (compound>reverse). There was no significant difference between two groups in GH (P= 0. 191)، IGF-I (P=0. 256) responses. Hence، compound and reverse superset resistance training may elicit similar growth responses; however، compound supersets might elicit more muscular damage compare to reverse supersets.

The aim of this study was to examine the concurrent consumption of creatine and resistance training on flexion strength of biceps brachii in female physical education students in their last semester. For this purpose، 30 students were randomly selected and divided into three groups: the experimental group 1 (age: 19. 8 ± 1. 4 yr، weight: 53. 9 ± 4. 4 kg، height: 162 ± 4. 4 cm)، experimental group 2 (age: 19. 6 ± 1. 3 yr، weight: 51. 2 ± 7. 5 kg، height: 162. 8 ± 5. 2 cm) and control group (age: 19. 8 ± 1. 0 yr، weight: 59 ± 3. 9 kg، height: 162 ± 4. 9 cm). All three groups performed the pretest and posttest after 6 weeks to measure the flexion strength of biceps brachii using a dynamometer. Experimental groups 1 and 2 participated in the 6-week McQueen resistance training program while experimental group 1 consumed creatine supplement and experimental group 2 consumed placebo. The control group did not participate in any training intervention and did not consume any supplements and placebo. To analyze the data within a group، dependent t test and among the groups، one-way ANOVA was used with SPSS ver. 18. The results showed that in the experimental group 1، the flexion strength of biceps brachii increased significantly after 6 weeks of concurrent consumption of creatine supplement and resistance training (P=0. 004). In the experimental group 2 (placebo)، no significant differences were observed in the amount of the strength of this muscle (P=0. 242). In the control group، strength significantly decreased (P=0. 001). In general، it can be concluded that the concurrent consumption of creatine supplement and resistance training can be beneficial in order to increase strength، especially for better performance in sport events.

The aim of the present study was to investigate the effect of 8 weeks of plyometric، strength and complex (plyometric-strength) training on the agility of young free style wrestler in Ilam city. This study was semi-experiment and its statistical population consisted of 328young free style wrestler of Ilam city. For this purpose، 40 subjects were randomly selected and divided into four groups (each group 10 subjects) of strength، plyometric، complex and control after Illinois agility test as their pretest. Then they performed training protocols for 8 weeks and again Illinois agility test was administered as the posttest. For data analysis، dependent t test، one-way analysis of variance and post hoc LSD test were used at PP<0. 05). Considering the differences among the groups، the results of one-way variance analysis showed no significant difference in agility among the groups in the pretest (f=856، P=0. 655) while after 8 weeks of training interventions، there was a significant difference (f=4. 48، P=0. 009). The results of post hoc LSD test showed that complex training، then plyometric and finally strength training had the highest effects on agility improvement. Of course، this difference was not significant between complex and plyometric groups and also between strength and control groups. It can be concluded that to improve the agility of wrestlers، plyometric training، particularly complex training (plyometric-strength) is more useful than only strength training. So this kind of training with an emphasis on research subjects'' characters and their input and output indexes is suggested.

The aim of this study was to investigate the acute effects of two resistance exercise protocols with slow and fast movements on some anabolic and catabolic hormones. Hence، in a randomized crossover design، 10 young men (age: 23. 3±1. 76 yr) were divided into 3 groups: control (Con)، resistance exercise with slow movement (SM)، and resistance exercise with fast movement (FM). Subjects performed 6 movements in 4 sets at 60–65% of 1RM. Blood sampling were taken before، immediately and 30 min. after the exercise. The results showed that both SM and FM significantly increased GH immediately after the exercise (250% and 200% respectively)، but there was no difference between SM and FM. In SM group، testosterone significantly increased immediately after the exercise. SM and FM had no effect on cortisol، insulin، and glucose. It can be concluded that SM has more effect on testosterone secretion compared with FM.

The aim of this study was to investigate the effect of moderate rhythm of music on perceived exertion and heart rate during different intensities of endurance training in young male athletes. 10 male athletic students (mean + SD age 21. 6±2. 60 years) were voluntarily selected. The present study was conducted in a crossover design with and without music. The results showed no significant difference between the two stages in heart rate during the warm-up phase (P>0. 05). During training with 60-70% of Maximal Heart Rate and moderate rhythm of music، heart rate and perceived exertion significantly decreased as compared to the condition without music (P<0. 05). During training with the highest intensity، the perceived exertion and heart rate showed a slight reduction but it was not significant (P>0. 05). The findings showed that moderate rhythm of music balances the effects of training intensity on heart rate and perceived exertion، but it does not have a great effect in higher intensities.

An increase in c-reactive protein inflammatory indicator and lipid profile is accompanied with an increase in cardiovascular risks. However، the effect of resistance exercises on these cardiovascular risk factors in females is unknown. The aim of this study was to examine the effect of 12 weeks of circuit exercise on c-reactive protein and lipid profile in inactive women. For this purpose، 24 young inactive women (mean age of 26±3. 50 years، height 160±2. 50 cm and weight 62±6. 93 kg) were selected voluntarily and divided randomly into two 12-subject groups (a control and an experimental). The exercise program included 12 weeks of circuit resistance exercise، 3 sessions a week، 20 to 60 minutes and 8 stations each session with 65-80% intensity of one repetition maximum (1RM). Blood samples were collected after 14 hours of fasting just before the project and also 48 hours after the last exercise session. Data were analyzed with Kolmogorov-Smirnov test (K-S test) and dependant and independent t tests at α≤0. 05. The Results showed that after 12 weeks of circuit resistance exercise in the experimental group، the amounts of CRP، TG، TC، LDL-C، VLDL-C changed significantly (P≤0. 05) while HDL-C did not change significantly (P≥0. 05). Finally، it seems that circuit resistance exercise can be considered as an effective and valuable method to prevent and reduce cardiovascular diseases in women and to improve their health as it decreases risk factors.