Research in Sport Medicine and Technology

Comparison the effect of comprehensive exercises of anterior cruciate ligament lnjury prevention along with feedback on knee function

Mohadse Salehi Sarbizhan

The most common side effect of physical activity is the risk of musculoskeletal damage, that anterior cruciate ligament injury is the most common one. Purpose of the study is comparing the effect of six weeks of comprehensive injury prevention training on anterior cruciate ligament with internal and external feedback on the proprioception and knee function of active female university students. Forty five active female university students aged 18-25 years were volunteered and randomly assigned to three groups (internal, external and control) and they performed the protocol three times a week for six weeks. Proprioception and function of the knee joint were measured using goniometer and functional tests in two stages namely pre-test and post-test. Statistical analysis of covariance, paired t test and Tukey's post hoc tests were used for statistical analysis with a significant level of p≤0.05. Overall results of the study showed that the present exercise protocol with internal and external feedback had a significant effect on the proprioception of p≤0.001 and p=0.000 for the knee performance and there was no significant difference between the two training groups. Regarding the results of the study, it is suggested that the present training protocol be addressed by coaches and sport sciences specialists as a complementary tool and method, along with other training methods, for those who are prone to damage to the anterior cruciate ligament.

Develop of native aerobic power prediction equation by the 6-minute walk test in healthy child

Farzad Nazem

Aerobic power (VO_2max) is an important indicator of the health and physical fitness. Executive problems in direct VO_2max measurement has led to developing sub-maximal aerobic power prediction equations. The purpose of present study was to develop native aerobic power prediction equation based on 6-Minute Walk Test (6MWT) and body composition indices in children. In 192 healthy children (8 to 12 years) VO_2max was objectively measured by Bruce treadmill protocol with gas analysis. The 6MWT was performed according to ATS guidelines. Also, anthropometric measurements were measured according to standard methods. Multiple regression analysis was used to design aerobic power (ml/kg/min) prediction equation. Accuracy of native VO_2max prediction equation was assessed by Pearson correlation and Bland-Altman approach between measured and predicted VO2max. Significant correlation was observed between direct VO2max and independent variables (r=0.25-0.734). Aerobic power of the boys could be predicted by weight and 6MWT according to the following equation: VO_2max(ml/kg/min)= 5.359 + (0.067 × 6MWD m) – (0.286 × Weight kg) (r²=0.743, SEE=2.74 ml/kg/min, p≤0.001). Strong correlation was observed between measured and predicted VO2max(r=0.861, P≤0.001). In addition, Bland and Altman plots demonstrated a high degree of consistency between measured and predicted VO2max. Exercise and fitness coaches by utilization of native aerobic prediction equation based on the 6MWT and weight could be able to assess the aerobic power of the boys and to evaluation of the effects of exercise training on cardio-respiratory fitness.

Effect of acute aerobic activity after a period of taking vitamin C supplement on Iron status and hematological indices of professional football players

Majid Mardaniyan Ghahfarrokhi

Vitamin C consumption is important in Iron absorption. Therefore, the purpose of this study was to investigate the effect of acute aerobic activity after two weeks vitamin C supplementation on Iron status and hematological indices in club football players. In this quasi-experimental study, 40 club football players from Khuzestan province were randomly divided into two groups of vitamin C and placebo. Daily and for 14 days, subjects received 400 mg vitamin C in vitamin C group and 400mg dextrose in placebo group. 48 hours after the end of supplementation, a Bruce test was performed. To measure Iron, Ferritin, RBC and Hb levels, four blood samples were taken from the subjects, before and after the supplementation, immediately after and 72 hours after the Bruce test. Repeated measure ANOVA and Two way analysis of variance was used. 2 weeks of vitamin C supplementation showed a significant increase in RBC (p=0.026), Hb (p=0.041), serum Iron (p=0.008) and serum Ferritin (p=0.004) compared to placebo group. After aerobic exhaustive activity, RBC (p=0.034), serum Iron (p=0.023) and Ferritin (p=0.031) in vitamin C group significantly decreases compared to placebo group. After 72 hours of recovery, the vitamin C group showed a significant increase in serum Iron (p=0.036) and Ferritin (p=0.045) compared to placebo group. It seems that two weeks of vitamin C supplementation can improve the serum Iron, Ferritin, RBC and Hb profile of professional footballers before aerobic exhaustive activity and in recovery.

Aquaporin-5 levels of lung following the taper program and Nigella sativa in the maturing rat

Akram Arzani

The aquaporin5 (AQP5) is an integral membrane protein that plays an important role in maintaining water homeostasis in the lung during of puberty. The purpose of this study was to evaluate the effect of period of reduced training with Nigella Sativa (NS) supplementation on AQP5 levels in the lung of Male Wistar rats during of puberty. 110 newborn three-week old male Wistar rats with average weight of 68±9 gr, were randomly divided into three groups included; the base, control and training groups. After a 6-week training period, the control group was divided into 2 groups with and without NS and training groups were divided into 6 groups including frequency, volume and intensity taper with and without NS. After 6 weeks, NS supplements were fed daily by gavages to groups of NS 500 mg/kg body weight. Progressive interval training was performed in 6 sessions, 30 minutes each session at a speed of 15 to70 meters per minute, Then, taper phase for three weeks in decreasing pattern, intensity, frequency and volume were performed. AQP5 levels were measured by ELISA methods. Analyzed is done with two-way ANOVA and LSD test at α≤0.05. While NS supplementation were increase average AQP5 levels in the taper groups of frequency, volume and intensity, But, there were no significant differences (P≥0/45) between AQP5 levels in with and without NS groups. Furthermore, three-week taper versus two weeks taper a significant increase the average AQP5 levels in the groups of with and without NS. It is suggested that the antihistaminic and antinociceptive effects of the NS with a period of reduced training with increasing levels of AQP5 would improve the physiological and functional parameters of the lung during of puberty.

The effect of shoulder abduction angles, shoulder dominance and non-dominance and external loading on shoulder muscles co-contraction ratio in overhead athletes and non-athletes

Hossein Hosseinimehr

The purpose of this study was to compare the effect of shoulder abduction angles, dominant and non-dominant arm and external loading on co-contraction ratio during arm abduction in scapular plane in overhead athletes and non-athletes. 10 swimmers, 10 handball players and 10 tennis players and ten non-athletes voluntarily participated in this study. Electromyography activity of shoulder muscles (middle and anterior deltoid; upper, middle and lower trapezius; infraspinatus, serratus anterior and latissimus dorsi) during dynamic and static arm abduction in 3 different angles (0-45º in 1second and holding it for 3 seconds, 0-90º in 2 seconds and holding it for 3 seconds, 0-135º in 1 second and holding it for 3 seconds) was recorded for dominant and non-dominant arm in loading and non-loading conditions. Co-contraction ratio of shoulder muscles was calculated for both groups. Findings indicated external loading, shoulder dominance and abduction angles had significant effect on shoulder muscles co-contraction ratio during (0-45º, 0-90º, 0-135º) and holding shoulder elevation in scapular plane (45º, 90º, 135º), also there was significant difference in shoulder muscles co-contraction ratio among four groups during and holding elevation in scapular plane (p≤0.05). Significant differences in shoulder muscles co-contraction ratio among athletes group and between athletes and non-athletes may be related to sport demands and adaptation to exercises and extensive use of upper limb as well.

The effect of six weeks selected physical training on balance, postural control and lower limb function in children with Meningomyelocele

Gholam Ali Ghasemi

Meningomyelocele after cerebral palsy is the most common congenital defects of the nervous system that impairs the functioning of many body’s structures. This study aimed to assess the effect of six weeks selected physical training on balance, postural control and lower limb function in children with Meningomyelocele. In this quasi-experimental study, 10 boys aged 10-11 years with Meningomyelocele in L4-L5 levels that independently able to stand and take at least 5 steps were selected and after obtaining written consent from the parents, placed in an experimental group. Before and after 6 weeks (four 60-minute sessions per week) participation in a researcher-designed exercise protocol, Static and dynamic balance (Balance Scale PBS), postural sway (foot pressure device), neck craniovertebral angle and knee and hip range of motion (goniometer), thoracic arch angle (flexible ruler) and trunk and knee extensors strength (dynamometer) were measured. Data by t-test in SPSS 22 software was analyzed (p≤0/05). The results were showed significant difference between pre-test and post-test in all variables except the total index of postural control and trunk extensors strength (P≥0/05). Due to the effectiveness of the used exercise protocol, this protocol can be used to improve the postural control, balance and lower extremity function in rehabilitation of patients with Meningomyelocele and similar to those.

Effect of an 8-week specific functional training on injury risk factors and athletic performance in male judokas

Hooman Minoonejad

Judo is one of the most popular martial arts in the world. Researchers reported a higher risk of injuries during training rather than the time of competition. So, the safe and effective training methods should be considered. As development and application of injury prevention approaches and athletic performance enhancement is necessary, the purpose of this study was to investigate the effect of 8-week Judo Specific Functional Training on the injury risk factors and athletic performance in non-elite male judokas. 46 non-elite judokas participated in this study. Subjects were randomly divided into two groups of experimental (23:N) and control (23:N). For a period of 8 weeks, the experimental group attended a special judo functional training program designed by the researchers. At the same time, the control group participated in the usual judo training program presented by the coaches. The exercises were performed 3 sessions per week and 90 minutes per session. The subjects participated in pre- and post-tests. After data collection, in order to approve data normality and compare the variables, Shapiro-wilk, ANCOVA analysis was implemented at the significant level (p≤0.05) using SPSS version 21. The results showed that scores of functional movement screening (p=0.001), upper extremity Y balance test (p=0.001), vertical jump (p=0.001) and special judo fitness test (p=0.001) significantly increased among the experimental group in comparison to the Control group. This Judo specific functional training program simultaneously modifies or decreases the injury risk factors and improves the athletic performance and has more efficiency and effectiveness rather than the usual judo training program.