ARTICLE INFO

Article Type

Original Research

Authors

Bararpour   E. (*)
Mirzaei   S. (1)
Chale Chale   M. (1)






(*) Department of Physiology & Sport Biomechanics, Physical Education & Sports Sciences Faculty, University of Mazandaran, Babolsar, Iran
(1) Department of Sport Physiology, West Tehran Branch, Islamic Azad University, Tehran, Iran

Correspondence

Address: Mazandaran University, Pasdaran Street, Babolsar, Mazandaran, Iran
Phone: +98 (11) 35303560
Fax: +98 (11) 35334253
eb.physio61@hotmail.com

Article History

Received:  June  27, 2017
Accepted:  December 30, 2018
ePublished:  April 25, 2018

BRIEF TEXT


High level of fitness is an essential attribute of military Officers [1]. The physical practices during the ‎military service term that are beyond the body's ability to recover may lead to overtraining syndrome ‎in military environments and contribute to development of stressors [2, 3]. … [4].‎

Chicharro et al. have investigated the 8-week training program for Spanish Special Forces (isometric ‎power, vertical jump, and Wingate test) and have come to the conclusion that such training leads to a ‎state of overtraining and a decrease in performance. … [5]. The eight-week Ranger training program in ‎Burke and Dyer's study led to a significant positive change in cardiovascular strength and Swedish ‎swimming, as well as significant negative changes in the pull-up test [6]. Some studies have confirmed ‎that there was no statistically significant difference in reducing the physical performance of specific ‎tasks for soldiers, like a polygon obstacle, uphill running, throwing grenades, shooting, lifting and ‎carrying, and running 1 mile and 300 yards as a consequence of reduced energy intake [7]. Pemrick ‎conducted a study to determine how much of each of the components of fitness (aerobic, anaerobic, ‎and muscular endurance, strength, speed, coordination and flexibility) are involved in physically ‎demanding tasks carried out by the rangers in battle. The results showed that the ranger regiment has a ‎high standard of fitness abilities and fitness programs that are mainly focused on aerobic endurance ‎‎[8]. Bovill et al. stated that special operations forces are a unique military population and show a ‎behavior similar to that of competitive athletes, especially at the level of fitness training and physical ‎stress [9]. … [10-18].‎

Features such as physical performance, agility and speed are fundamental attributes of some specific ‎groups in the military. The ranger forces are one of the most elite units of the Armed Forces, and the ‎best trained and equipped Special Forces units. According to the few studies conducted in this field, it ‎seems that many physiological parameters are related to the physical fitness of military officers, and ‎can increases their ability and accelerate stress relief. The present study was an attempt to investigate ‎the effectiveness of a Ranger training program on physical fitness and levels of testosterone hormones ‎and the LH / FSH ratio among students at Imam Ali Officers' University.‎

This is a pretest–posttest quasi-experimental study with control group.‎

This research was conducted on all the second year students of Imam Ali Officers' University in 2015.‎

Given that a total of 25 people volunteered to participate in the study, 24 samples were selected ‎according to the Morgan table, and were randomly divided into two 12-member experimental and ‎control groups.‎

Sit and reach flexibility tests, 20 m sprint, 4 x 9 m agility meter and Sargent jump test were used for ‎data collection in the fitness test. The hormones were also measured using conventional blood tests. ‎After designing the training station layout, all the stages of the test and how each test was supposed to ‎be performed was explained and practically presented by the researchers. The subjects first warmed up ‎for 20 minutes and then performed the determined tests to evaluate the flexibility, speed, agility and ‎anaerobic power in the pre-test stage. The Results were recorded in special forms. 2 days later, the ‎subjects referred to the laboratory and blood samples were taken from them to evaluate the levels of ‎testosterone hormones and the LH / FSH ratio. In the next stage, an 8-week Ranger training program ‎was performed in the experimental group but the control group did not participate in any training ‎course during this period. After completion of the training course, the necessary tests were performed ‎to collect the required data for the post-test stage, and the results were compared with the results ‎obtained in the pre-training stage. It should be noted that blood samples of the pre-test and post-test ‎stages were taken at 8 AM and in fasting state. Descriptive statistics were used to describe the data and ‎independent t-test was performed using SPSS 21 software in order to analyze the data.‎

During the 8-week training period, the testosterone concentration of the subjects decreased by 61.25% ‎‎(p=0.001). However, the effect of this course on the LH / FSH ratio was not significant (p>0.05) (Table ‎‎1). In addition, the results showed that the 8 -week ranger training course had a significant effect on ‎anaerobic power of subjects (p=0.44). However, the effect of this training course on speed, agility and ‎flexibility was not significant (p>0.05) (Table 2).‎

The results of the present study are consistent with the results of Nindl et al. and Friedl et al. studies ‎on the Norwegian and American ranger forces [19, 20]. Researchers have shown that intake of extra ‎nutrition may lower testosterone levels in military training. They have also shown that reduction in ‎testosterone levels can be attributed to reduced secretion of the LH hormone compared to FSH [21]. ‎Reduced secretion of Gonadotropin-releasing hormone stimulator in the hypothalamus during the ‎course of the study leads to an increased production of LH compared to FSH which triggers the ‎secretion of Gonadotropin-releasing hormone. This suggests that androgen secretion during exercises ‎is regulated by the hypothalamus and other brain regions [10]. ... [22]. The results of the present study ‎are not consistent with the results of Giro et al. and Hironetrakol et al. study on the effect of strength ‎training on the testosterone levels [23, 24]. The nutritional pressure and psychological stress during ‎the training course could be taken into account as one of the factors that contribute to inconsistency of ‎the present study’s results with those of the afore-mentioned studies. In addition, in this study, ‎significant correlation was observed between the training courses and the changes in anaerobic power ‎of subjects. Some studies have been conducted on the effect of training on the anaerobic power, as well ‎as the effect of physical exercises and performance parameters in military environments [19, 20, 25]. ‎In the study conducted by Nindl et al., the explosive strength and the maximum lift power of subject ‎decreased by 20% after 8 weeks of intensive military training. The results of the present study are ‎consistent with the results of Chicharro et al., Burke and Dyer and Sporis et al. [5, 6, 26].‎

Considering the decrements in physical performance during periods of an energy deficit, the military ‎forces should place special emphasis on achieving high levels of strength, power, and muscularity ‎through optimal physical training programs and food. In addition, optimization of training courses ‎considered for improving physical performance before operation, can counter some of the adverse ‎effects of the training course on the physical performance. The authors are required to account for the ‎impact of military stress on speed, because mobility power of soldiers during an operation plays a ‎fundamental role in their survivability.‎

The limitations of the present study include failure to measure other factors associated with physical ‎fitness. In addition, measurement of other biomarkers such as stress hormones associated with ‎testosterone levels could contribute to better understanding of changes during the training course.‎

The 8-week ranger training course contributes to reduction of testosterone levels and increased ‎anaerobic power of subjects, but doesn’t affect the LH/FSH ratio in subjects.‎

The authors would like to express their thankfulness to Brigadier general Fathollah Rashidzadeh and ‎others for their contribution and support.‎

There is no conflict of interests in the present study.‎

The present study was conducted with approval of ethics committee of Imam Ali Officers' University.‎

The present study was supported by the Vice Chancellor for Research at Imam Ali Officers' University.‎

TABLES and CHARTS

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