hamid rajabi - Academia.edu (original) (raw)
Papers by hamid rajabi
Comparative Exercise Physiology, Jan 11, 2021
Neuromuscular function is one of the important factors affecting athletic performance. Previous s... more Neuromuscular function is one of the important factors affecting athletic performance. Previous studies have shown that fish oil supplementation can improve performance. This study investigated the effect of fish oil on neuromuscular performance after exhausting exercise. Eighteen healthy men (mean ± standard deviation; age 26.9±2.6 years; weight 78.33±10.42 kg; height 175.8±4.9 cm; body fat percentage 18.40±5.46%) voluntarily participated and were randomly assigned to fish and corn oil groups in a double blind manner. Participants received 6 g/day of oil for 4 weeks, while maintaining baseline diet and training status during the study. Changes in maximal voluntary contraction (MVC) of the tibialis anterior muscle, neuromuscular propagation of tibialis anterior muscle (M-wave), corticospinal excitability (MEP: motor evoked potential), and the rate of perceived exertion (RPE) were evaluated before and after supplementation in response to a modified Bruce exhausting protocol. Group differences in changes in each variable following supplementation were assessed by two-way analysis of variances (ANOVA). Compared to corn oil, fish oil demonstrated less perceived exertion at the end of exhaustive exercise (F=9.72, P=0.001) after supplementation, and normalised MEP to M-wave showed a trend (F=3.83, P=0.071). However, M-wave peak to peak amplitudes changes were not significant between the groups (P>0.05). In addition, significant differences were observed between baseline MVC values of the group following supplementation. Thus, it seems that fish oil can improve corticospinal excitability, thereby improving neuromuscular function in exhausting activities. Therefore, fish oil supplementation may be recommended to increase performance in activities otherwise limited. However, the mechanism underlying this effect remains to be elucidated.
According to the controversy about the role of ATF3 as a non-inflammatory index of myocardia in m... more According to the controversy about the role of ATF3 as a non-inflammatory index of myocardia in metabolic abnormalities as diabetes, the purpose of this study was to compare the effect of high intensity interval versus progressive resistance training on ATF3 myocardial gene expression of male diabetic rats. Methods: Sixty male six weeks rats with a weighing average of 150 g were randomly divided into five groups: diabetic (D), diabetes-high intensity interval training (DIT), high intensity interval training (HIIT), resistance (RT), and diabetes-resistance training (DRT). High intensity interval training included 10 repetitions of one minute running on a treadmill with two minutes of rest. Progressive resistance training included four climb of a resistance ladder with weights. The training program was performed three days a week for six weeks. Data analysis was performed using Fisher's and M-ANOVA tests at a significant level of P ≤ 0.01. Results: Significant increase in expression of ATF3 in diabetes-high intensity interval training group was observed between diabetes and diabetes-high intensity interval training (P <0.001). Between two groups of diabetes and diabetes-resistance training (P = 0.001), there was a significant increase in expression in diabetes-resistance training. In comparison between DIT and DRT groups, progressive respond were observed in DIT versus DRT (P = 0.03). Conclusion: high intensity interval training has been shown to be more effective in comparison with the progressive resistance training, because it activates more different molecular cell mechanisms, perhaps, significantly reduces the negative effects of diabetes mellitus on cardiovascular disease.
Scientific Reports, Jun 6, 2023
Athletic women have shown a higher risk of ACL injury during jump landing compared to men. Plyome... more Athletic women have shown a higher risk of ACL injury during jump landing compared to men. Plyometric training can be an alternative way to minimize the risk of knee injuries via the changed muscle activity patterns. Hence, the aim of this study was to determine the effects of a 4-week plyometric training program on the muscle activity pattern in different phases of one-leg drop jump in active girls. Active girls were randomly allocated into 2 groups (Plyometric training = 10, Control group = 10) where the plyometric training group (PTG) performed 60 min exercises, 2 sessions/1 week for 4 weeks while the control group (CG) had their daily activity. In the pre to post test, the sEMG was recorded from the Rectus Femoris (RF), Biceps Femoris (BF), Medial Gastrocnemius (GaM), and Tibialis Anterior (TA) muscles of the dominant leg during the Preparatory phase (PP), Contact Phase (CP), Flight Phase (FP) of one-leg drop jump. Electromyography variables (Signal amplitude, Maximum activity, Time to peak (TTP), Onset and activity time and Order muscle activity) and Ergo jump variables (Time of preparatory phase (TPP), Time of contact phase (TCP), Time of flight (jump height) phase (TFP), and Explosive power were analyzed. The Univariate ANCOVA test showed a significant difference between the two groups in Activity Time, whilst adjusting for pre-test as a Covariate, only in TA muscle (F (1,17) = 5.09, p = 0.038, η 2 = 0.230). In PTG. TA (− 15%), GaM (− 19%), and BF muscles (− 9%) started their activity earlier while there was no significant difference between the two groups at the Onset time. TTP of RF was significantly different between the 2 groups only in the PR phase (0.216 ± 0.07 vs 0.153 ± 0.09 s) (p = 0.049, 95% CI = 0.001, 0.127). Results of the present study suggest that a 4-week plyometric training can improve the stability of leg joints via earlier recruitment of muscles and change activity patterns in lower limb muscles. It also recommends that the preparatory phase before landing be considered an important stage in preventing sports injuries in a training program. Plyometric training is generally expected to enhance performances during stretch-shortening cycle (SSC) exercises. Among the mechanisms of plyometric training, it is possible to mention the potential of the electric currents of the muscle (neural adaptations), biochemical-mechanical potential, and restoring the elastic energy of the muscles 1,2. Plyometric training causes modulation in the action of deep muscle receptors. Studies have shown that the muscle spindle participates in power output through a stretch reflex mechanism in plyometric training 3. By contrast, another proprioceptor, Golgi tendon organs (GTOs), located in tendons, mainly prevents muscle over-contraction 3 , which reduces the sensitivity of this organ to plyometric training 4 , which increases the recruitment of motor units and changes the pattern of muscle activity during jumping 5,6. Therefore, plyometric
Comparative Biochemistry and Physiology B, Apr 1, 2023
Razi Journal of Medical Sciences, May 10, 2021
This study is mainly concerned with designing and implementing an Advanced Physical Fitness Asses... more This study is mainly concerned with designing and implementing an Advanced Physical Fitness Assessment software (APFA) for the Iranian society. This applied study was intended to improvement, complement and facilitate the measurement and evaluation methods of motor and health physical fitness criteria. The software was designed using various tests and their calculation formulas as well as national and international norms, percentage rank, and T and Z scores. Correlational analysis of the assessment data from 100 individuals using APFA and the results obtained from Excel and manual methods with an intraclass correlation (ICC=1, P
Jundishapur Scientific Medical Journal, Jan 21, 2018
This study aimed to investigate the effects of acute and chronic pyramid and reverse pyramid resi... more This study aimed to investigate the effects of acute and chronic pyramid and reverse pyramid resistance training on growth factor (IGF-1) and serum cell injury index (Creatine kinase) in non-athlete girls and also to assess the possible relationship between CK and IGF-1. ...
Journal of Isfahan Medical School, 2018
Tehran University Medical Journal TUMS Publications, Aug 15, 2015
The purpose of this study was to investigate the relationship between professional physical and t... more The purpose of this study was to investigate the relationship between professional physical and technical tests of young and adult Iranian basketball national teams. The sample groups were comprised of fifty athletes who were selected from among young (age: 16/8± 0/37 years, ...
Journal of Strength and Conditioning Research, Oct 1, 2009
Nikooie, R, Gharakhanlo, R, Rajabi, H, Bahraminegad, M, and Ghafari, A. Noninvasive determination... more Nikooie, R, Gharakhanlo, R, Rajabi, H, Bahraminegad, M, and Ghafari, A. Noninvasive determination of anaerobic threshold by monitoring the %Spo 2 changes and respiratory gas exchange. J Strength Cond Res 23(7): 2107-2113, 2009-The purpose of this study was to determine the validity ...
Gene Reports, Mar 1, 2022
Iranian Red Crescent Medical Journal, May 5, 2019
Background: The response of microRNA (miR-1), upstream regulators (Myogenic Differentiation 1 (My... more Background: The response of microRNA (miR-1), upstream regulators (Myogenic Differentiation 1 (MyoD1) and Myocyte Enhancer Factor 2C (Mef2C)), and a downstream target (Histone Deacetylase 4 (Hdac4)) to an acute bout of Resistance Exercise (RE) in Extensor Digitorum Longus (EDL) and soleus muscles has remained elusive. Objectives: In this experimental study, we investigated the effect of an acute bout of RE on the expression of miR-1, MyoD1, Mef2C, and Hdac4 genes in the slow and fast-twitch muscle of rats. Methods: The current study was conducted at Tarbiat Modares University, Tehran, Iran, in 2017. Fifteen male Wistar rats were randomly divided into two groups, control (n = 5) and RE (n = 10). The RE protocol consisted of four sets of five repetitions of climbing a ladder with weights attached to the tails of rats. The soleus and EDL muscles of rats were collected at 3 h (n = 5) and 6 h (n = 5) post-RE. The real-time polymerase chain reaction was used to measure the levels of miR-1, MyoD1, Mef2C, and Hdac4 mRNA expression. Results: The miR-1 expression in EDL muscle was significantly lower at 3 h and 6 h post-exercise in the RE group than in the control group (P < 0.01). The miR-1 expression in soleus muscle was significantly lower at 3 h post-exercise in the RE group than in the control group (P < 0.007) but it was significantly higher at 6 h post-exercise (P < 0.036). The expression of MyoD1, Mef2C, and Hdac4 genes in the EDL muscle was higher in the RE group than in the control group (P < 0.01). The expression of these genes in response to RE had more fluctuations in soleus muscle. Conclusions: It can be concluded that miR-1 expression in extensor digitorum longus and soleus muscles of rats responds to resistance exercise in different manners and this coincides with a change in upstream regulators and downstream target.
Journal of Arak University of Medical Sciences, Feb 10, 2019
This open-access article distributed under the terms of the Creative Commons Attribution NonComme... more This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 4.0 License (CC BY-NC 4.0).
Comparative Exercise Physiology, Jan 11, 2021
Neuromuscular function is one of the important factors affecting athletic performance. Previous s... more Neuromuscular function is one of the important factors affecting athletic performance. Previous studies have shown that fish oil supplementation can improve performance. This study investigated the effect of fish oil on neuromuscular performance after exhausting exercise. Eighteen healthy men (mean ± standard deviation; age 26.9±2.6 years; weight 78.33±10.42 kg; height 175.8±4.9 cm; body fat percentage 18.40±5.46%) voluntarily participated and were randomly assigned to fish and corn oil groups in a double blind manner. Participants received 6 g/day of oil for 4 weeks, while maintaining baseline diet and training status during the study. Changes in maximal voluntary contraction (MVC) of the tibialis anterior muscle, neuromuscular propagation of tibialis anterior muscle (M-wave), corticospinal excitability (MEP: motor evoked potential), and the rate of perceived exertion (RPE) were evaluated before and after supplementation in response to a modified Bruce exhausting protocol. Group differences in changes in each variable following supplementation were assessed by two-way analysis of variances (ANOVA). Compared to corn oil, fish oil demonstrated less perceived exertion at the end of exhaustive exercise (F=9.72, P=0.001) after supplementation, and normalised MEP to M-wave showed a trend (F=3.83, P=0.071). However, M-wave peak to peak amplitudes changes were not significant between the groups (P>0.05). In addition, significant differences were observed between baseline MVC values of the group following supplementation. Thus, it seems that fish oil can improve corticospinal excitability, thereby improving neuromuscular function in exhausting activities. Therefore, fish oil supplementation may be recommended to increase performance in activities otherwise limited. However, the mechanism underlying this effect remains to be elucidated.
According to the controversy about the role of ATF3 as a non-inflammatory index of myocardia in m... more According to the controversy about the role of ATF3 as a non-inflammatory index of myocardia in metabolic abnormalities as diabetes, the purpose of this study was to compare the effect of high intensity interval versus progressive resistance training on ATF3 myocardial gene expression of male diabetic rats. Methods: Sixty male six weeks rats with a weighing average of 150 g were randomly divided into five groups: diabetic (D), diabetes-high intensity interval training (DIT), high intensity interval training (HIIT), resistance (RT), and diabetes-resistance training (DRT). High intensity interval training included 10 repetitions of one minute running on a treadmill with two minutes of rest. Progressive resistance training included four climb of a resistance ladder with weights. The training program was performed three days a week for six weeks. Data analysis was performed using Fisher's and M-ANOVA tests at a significant level of P ≤ 0.01. Results: Significant increase in expression of ATF3 in diabetes-high intensity interval training group was observed between diabetes and diabetes-high intensity interval training (P <0.001). Between two groups of diabetes and diabetes-resistance training (P = 0.001), there was a significant increase in expression in diabetes-resistance training. In comparison between DIT and DRT groups, progressive respond were observed in DIT versus DRT (P = 0.03). Conclusion: high intensity interval training has been shown to be more effective in comparison with the progressive resistance training, because it activates more different molecular cell mechanisms, perhaps, significantly reduces the negative effects of diabetes mellitus on cardiovascular disease.
Scientific Reports, Jun 6, 2023
Athletic women have shown a higher risk of ACL injury during jump landing compared to men. Plyome... more Athletic women have shown a higher risk of ACL injury during jump landing compared to men. Plyometric training can be an alternative way to minimize the risk of knee injuries via the changed muscle activity patterns. Hence, the aim of this study was to determine the effects of a 4-week plyometric training program on the muscle activity pattern in different phases of one-leg drop jump in active girls. Active girls were randomly allocated into 2 groups (Plyometric training = 10, Control group = 10) where the plyometric training group (PTG) performed 60 min exercises, 2 sessions/1 week for 4 weeks while the control group (CG) had their daily activity. In the pre to post test, the sEMG was recorded from the Rectus Femoris (RF), Biceps Femoris (BF), Medial Gastrocnemius (GaM), and Tibialis Anterior (TA) muscles of the dominant leg during the Preparatory phase (PP), Contact Phase (CP), Flight Phase (FP) of one-leg drop jump. Electromyography variables (Signal amplitude, Maximum activity, Time to peak (TTP), Onset and activity time and Order muscle activity) and Ergo jump variables (Time of preparatory phase (TPP), Time of contact phase (TCP), Time of flight (jump height) phase (TFP), and Explosive power were analyzed. The Univariate ANCOVA test showed a significant difference between the two groups in Activity Time, whilst adjusting for pre-test as a Covariate, only in TA muscle (F (1,17) = 5.09, p = 0.038, η 2 = 0.230). In PTG. TA (− 15%), GaM (− 19%), and BF muscles (− 9%) started their activity earlier while there was no significant difference between the two groups at the Onset time. TTP of RF was significantly different between the 2 groups only in the PR phase (0.216 ± 0.07 vs 0.153 ± 0.09 s) (p = 0.049, 95% CI = 0.001, 0.127). Results of the present study suggest that a 4-week plyometric training can improve the stability of leg joints via earlier recruitment of muscles and change activity patterns in lower limb muscles. It also recommends that the preparatory phase before landing be considered an important stage in preventing sports injuries in a training program. Plyometric training is generally expected to enhance performances during stretch-shortening cycle (SSC) exercises. Among the mechanisms of plyometric training, it is possible to mention the potential of the electric currents of the muscle (neural adaptations), biochemical-mechanical potential, and restoring the elastic energy of the muscles 1,2. Plyometric training causes modulation in the action of deep muscle receptors. Studies have shown that the muscle spindle participates in power output through a stretch reflex mechanism in plyometric training 3. By contrast, another proprioceptor, Golgi tendon organs (GTOs), located in tendons, mainly prevents muscle over-contraction 3 , which reduces the sensitivity of this organ to plyometric training 4 , which increases the recruitment of motor units and changes the pattern of muscle activity during jumping 5,6. Therefore, plyometric
Comparative Biochemistry and Physiology B, Apr 1, 2023
Razi Journal of Medical Sciences, May 10, 2021
This study is mainly concerned with designing and implementing an Advanced Physical Fitness Asses... more This study is mainly concerned with designing and implementing an Advanced Physical Fitness Assessment software (APFA) for the Iranian society. This applied study was intended to improvement, complement and facilitate the measurement and evaluation methods of motor and health physical fitness criteria. The software was designed using various tests and their calculation formulas as well as national and international norms, percentage rank, and T and Z scores. Correlational analysis of the assessment data from 100 individuals using APFA and the results obtained from Excel and manual methods with an intraclass correlation (ICC=1, P
Jundishapur Scientific Medical Journal, Jan 21, 2018
This study aimed to investigate the effects of acute and chronic pyramid and reverse pyramid resi... more This study aimed to investigate the effects of acute and chronic pyramid and reverse pyramid resistance training on growth factor (IGF-1) and serum cell injury index (Creatine kinase) in non-athlete girls and also to assess the possible relationship between CK and IGF-1. ...
Journal of Isfahan Medical School, 2018
Tehran University Medical Journal TUMS Publications, Aug 15, 2015
The purpose of this study was to investigate the relationship between professional physical and t... more The purpose of this study was to investigate the relationship between professional physical and technical tests of young and adult Iranian basketball national teams. The sample groups were comprised of fifty athletes who were selected from among young (age: 16/8± 0/37 years, ...
Journal of Strength and Conditioning Research, Oct 1, 2009
Nikooie, R, Gharakhanlo, R, Rajabi, H, Bahraminegad, M, and Ghafari, A. Noninvasive determination... more Nikooie, R, Gharakhanlo, R, Rajabi, H, Bahraminegad, M, and Ghafari, A. Noninvasive determination of anaerobic threshold by monitoring the %Spo 2 changes and respiratory gas exchange. J Strength Cond Res 23(7): 2107-2113, 2009-The purpose of this study was to determine the validity ...
Gene Reports, Mar 1, 2022
Iranian Red Crescent Medical Journal, May 5, 2019
Background: The response of microRNA (miR-1), upstream regulators (Myogenic Differentiation 1 (My... more Background: The response of microRNA (miR-1), upstream regulators (Myogenic Differentiation 1 (MyoD1) and Myocyte Enhancer Factor 2C (Mef2C)), and a downstream target (Histone Deacetylase 4 (Hdac4)) to an acute bout of Resistance Exercise (RE) in Extensor Digitorum Longus (EDL) and soleus muscles has remained elusive. Objectives: In this experimental study, we investigated the effect of an acute bout of RE on the expression of miR-1, MyoD1, Mef2C, and Hdac4 genes in the slow and fast-twitch muscle of rats. Methods: The current study was conducted at Tarbiat Modares University, Tehran, Iran, in 2017. Fifteen male Wistar rats were randomly divided into two groups, control (n = 5) and RE (n = 10). The RE protocol consisted of four sets of five repetitions of climbing a ladder with weights attached to the tails of rats. The soleus and EDL muscles of rats were collected at 3 h (n = 5) and 6 h (n = 5) post-RE. The real-time polymerase chain reaction was used to measure the levels of miR-1, MyoD1, Mef2C, and Hdac4 mRNA expression. Results: The miR-1 expression in EDL muscle was significantly lower at 3 h and 6 h post-exercise in the RE group than in the control group (P < 0.01). The miR-1 expression in soleus muscle was significantly lower at 3 h post-exercise in the RE group than in the control group (P < 0.007) but it was significantly higher at 6 h post-exercise (P < 0.036). The expression of MyoD1, Mef2C, and Hdac4 genes in the EDL muscle was higher in the RE group than in the control group (P < 0.01). The expression of these genes in response to RE had more fluctuations in soleus muscle. Conclusions: It can be concluded that miR-1 expression in extensor digitorum longus and soleus muscles of rats responds to resistance exercise in different manners and this coincides with a change in upstream regulators and downstream target.
Journal of Arak University of Medical Sciences, Feb 10, 2019
This open-access article distributed under the terms of the Creative Commons Attribution NonComme... more This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 4.0 License (CC BY-NC 4.0).