Sport Sciences and Health Research

Background: Water polo (WP) is a sport with great aerobic/ anaerobic physiological demands. There are few studies that have evaluated the physical demands during the WP game and its relationship with the physiological indices of aerobic fitness Aim: Our aim was to determine the aerobic/ anaerobic profiles of the WP athletes through specific test. Materials and Methods: WP male athletes participated in this study (24.5±5.6 years, 85.9±10.3 kg, 183.0±6.3 cm, n=23). The athletes performed an anaerobic WP test (TAnaWP) to determine the height (Alt- cm) of the 1st/ 15th/ 30th jumps, total time(s) of the jumps (TT30) and the fatigue index (FI). Blood lactate kinetics were determined immediately after (Lac0 min) and during the recovery period; Lac 1/ 3/ 5/ 8/ 12 min. They also performed an aerobic water polo test (TAerWP) to determine maximal oxygen consumption (VO 2 max) a heart rate (HRmax), peak blood lactate (Lacp) and the second lactate threshold (LL2). Results: The following results (in cm) were obtained in TAnaWP: Alt1st (44±6), Alt15th (32±7) and Alt30th (24±9); TT30 (56.9±9.5); FI (42.0±12.5%); (Lac0), (Lac1), (Lac3), (Lac5), (Lac8) and (Lac12) (5.2±1.7; 7.8±1.6; 9.0±2.0; 9.4±2.2; 9.2±2.7; 8.5±2.2 mmol/L, respectively). The mean maximal values for the aerobic test were: VO 2 max=44.4±5.3 ml/kg/min, HRmax=174.3±9.1 bpm, Lacp=8.6±2.1 mmol/L. The values obtained at LL2 were: 157.5±13.5 bpm/ 90.5±8.2% HRmax). Conclusion: The proposed tests may be a possibility to determining the physiological fitness of WP athletes.

Background: Adropin is a newly identified bioactive protein that is important in energy hemostasis and vascular endothelial function. Aim : The purpose of the present study was to investigate plasma levels of adropin and nitrite/nitrate (NO), in elderly treated hypertensive subjects at baseline and follow-up after 6 weeks of high-intensity interval training (HIIT). Material and Methods: Forty-four elderly participants with treated hypertensives (age 61.09±5.82 years, 25 male and 19 female, BMI= 25.7±1.31 kg/m 2 ) were randomly assigned to either the high-intensity interval training (HIIT) or control group. The HIIT group received an intervention consisting of 10 intervals of 1.5 min at 85% to 90% of their heart rate reserve (HRR), separated by 2 min of rest at 50% to 55% of their HRR, in three sessions per week for a duration of six weeks. Plasma levels of adropin and NO were measured using enzyme-linked immunosorbent assay. The statistical analysis was performed by two-way repeated ANOVA to determine differences between groups and Pearson’s correlation coefficient to determine correlation. Results: The results showed that, following the six-week HIIT intervention, the plasma levels of adropin and NO significantly increased when compared to both control group ( P = 0.0016) and the baseline ( P = 0.0003) measurements. Peak oxygen consumption was increased after exercise training compared to the control group ( P =0.005). Δ adropin in the HIIT group showed a positive correlation with increased Δ NO (r= 0.707, P = 0.002) and Δ VO 2 peak (r= 0.836, P = 0.001), and a negative correlation with Δ DBP (r= 0.643, P = 0.025) and Δ SBP (r= 0.691, P = 0.013). Conclusions: The study findings suggests that HIIT can enhance both blood pressure and cardiorespiratory fitness. The observed increase in plasma level of adropin may have contributed to reduction of blood pressure by promoting nitric oxide production.

Background: Sports facilities are one of the most commonly used services in the city with a significant role in improving the physical and mental health condition of citizens thus a proper procedure is required to locate and distribute them. Aim : The purpose of this study is to design a comprehensive model for the optimal location of sports facilities. Materials and Methods: The research method is descriptive-analytic based on information gathering and is applied research based on objectives. The opinions of 20 experts have been used to design the model using the Delphi method, and weighting the effective criteria in the sports facilities location. The weight of each criterion has been obtained as population density (0.47), access (0.31), development potential (0.14), and adjacency (0.08); furthermore, the Kendall coefficient of concordance (0.74) in the third step of the Delphi method shows the strong agreement between the experts, regarding the proposed model. The proposed model consisted of six steps: 1. Aim; 2. Verification of the functional area of the existing sport facilities and specific restrictions of the area; 3. Introducing and weighting the important criteria in the sports facilities location; 4. Identifying the most suitable locations for constructing the sports facilities; 5. Evaluating the needs of users; 6. Selecting the best spaces and prioritizing them. Results: The results of the model showed that the most important criteria for locating sport facilities are population density, access, development potential, and adjacency. Additionally, it was indicated that the agreement between the experts increased over time. Conclusion: According to the proposed model, it is possible to identify the points that are suitable for constructing the new sports facilities.

Background: Telomerase activity plays a key role in preserving telomere length which is important in cellular aging. There is evidence showing the link between sirt6, irisin, and telomerase activity.   Aim : The aim of this study was to compare the effect of 8 weeks of high-intensity interval training (HIIT) and aerobic continuous training (ACT) on telomerase activity, sirt6, and irisin levels of healthy older adults. Materials and Methods: Thirty healthy males (age: 60-70 years, weight: 68-72 kg) participated voluntarily to follow the 8-week program including 3 sessions per week. Rest ratio in HIIT training was 1:2 and the intensity corresponded to 90% of HRR. ACT intensity was progressive starting with 50% of HRR and finishing with 70% of HRR. Blood samples were taken in a 12-hour fasting situation, before and after the program. Results: Results showed a significant effect of training on serum telomerase and sirt6 in training groups, not the control group. Also, in comparison to ACT and the control group, serum irisin was significantly higher in the HIIT group. Conclusion: We concluded HIIT training is safe and efficient for older adults in terms of telomerase activity, sirt6, and irisin level and can be followed as a time-efficient training protocol.

Background : Beyond biological changes, ageing is often associated with degenerative and progressive changes in functional and physiological performance. Different types of exercise and rehabilitation method were introduced for resolving or preventing aging complications. Aim: The aim of this study was to investigate the effects of 8- week- dynamic neuromuscular stabilization (DNS) training on functional performance and quality of life in healthy elderly men. Materials and Methods: Twenty-eight old men were selected by convenience sampling manner and divided randomly in two groups of experimental (n=13, age: 65.8±4.3 years, height: 1.63±5.92 cm, weight: 69.1±7.4 kg) and control (n=15, age: 66.3±3.8 years, height: 1.64±4.89 cm, weight: 70.1± 6.3 kg). The experimental group received neuromuscular stabilization training for 8 weeks and 3 sessions for 1 hour in a clinic in Baghdad. Static balance (by functional reach test), dynamic balance (by time-up and go test), functional performance (by Berge test), and quality of life (by Leiden-Padua (LEIPAD e questionnaire) were measured before and after training. Data was analyzed by repeated measure ANOVA in SPSS software. P value was set at P ≤0.05. Results : The results showed that the intergroup interaction in the variables of functional performance (F=53.3, P =0.00), quality of life (F=65.04, P =0.00), static (F=106.7, P =0.00) and dynamic (F=26.99, P =0.00) balance was significant with the superiority of the DNS group. Conclusion: Postural control, functional performance and quality of life improved after training protocol. Therefore, DNS training can be used as a complementary method for rehabilitation of elderly.

Background: The COVID-19 pandemic has resulted in global home confinement and quarantine, leading to the vaccination of societies worldwide. However, some elite athletes have negative views toward vaccination. Aim: This study aimed to compare the lifestyle of vaccinated versus unvaccinated international elite athletes during the COVID-19 pandemic. Materials and Methods: From March to October 2021, an online survey was conducted, including socio-individual information of athletes, the International Physical Activity Questionnaire (IPAQ), the Rapid Eating Assessment for Participants (REAP-S), and the Petersburg Sleep Quality Questionnaire (PSQI). A total of 581 elite athletes from 4 continents (Europe, Asia, Africa, and America) and different countries, aged 18-35 years, were voluntarily recruited. Data analysis was performed using U-Mann-Whitney and Wilcoxon signed-rank tests, with the level of significance set at alpha P <0.05. Results: The results indicated that there was a significant difference between the level of physical activity and eating behavior of vaccinated versus unvaccinated elite athletes ( P <0.001). However, no significant difference was found between the quality of sleep among vaccinated and unvaccinated elite athletes ( P =0.270). Conclusion: It was shown that, despite the unvaccinated status of some elite athletes (49.9%), their physical activity levels were higher than those of vaccinated elite athletes during the COVID-19 pandemic. Additionally, the eating behavior of vaccinated elite athletes was better than that of unvaccinated elite athletes during the COVID-19 pandemic, but there was no significant difference in the quality of sleep between the groups.

Background: Intense physical activity increases the production of reactive oxygen species in vital tissues such as the liver and causes oxidative stress. Aim: This study investigates the effect of high-intensity interval training and intense endurance training on oxidative stress of liver tissue in immature male rats during puberty. Materials and Methods: A total of 24 male Wistar rats (aged= 22 days, weight= 60±0.63 g), after one week of acclimatization, were divided randomly into three groups: control, IET, and HIIT. Rats were subjected to a four-week training on an animal treadmill. The effects of training treatment in rat liver were investigated by assaying oxidative stress biomarkers. Results: Comparing to control group, in both training groups significantly lower Malondialdehyde (MDA) was seen (( P (IET)= 0.016/ P (HIIT)= 0.020). However, there were no statistical differences in Glutathione Peroxidase (GPX) ( P = 0.463) and total antioxidant capacity (TAC) activity levels ( P = 0.194) among groups. HIIT training significantly increased superoxide dismutase (SOD) ( P = 0.040) and catalase enzyme (CAT) levels ( P = 0.007). IET and HIIT had significantly increased endurance performance (both: P = 0.001). Conclusion: Both training intensities did not lead to an increase in oxidative stress and can be used during puberty.

Background: Transmembrane protein fibronectin type III domain-containing protein 5 (FNDC5) is as a myokine, metabolic regulator and potential therapeutic agent which is known as a potential trait for metabolism and obesity. Aim: The purpose of this study was to evaluate the effect of high intensity interval swimming training on circulating irisin and some metabolic syndrome in postmenopausal overweight women. Materials and Methods: Thirty postmenopausal overweight women (55.73 ± 2.66 years, 26.72±2.33 kg/m 2 ) were randomized into high intensity interval swimming training (n=15; HIIT) and control groups (n=15; CON). HIIT performed 6–10×30 s swimming interspersed by 2 min recovery for an 8-week period completing 24±1 session (average heart rate= 0.89±0.029% HRmax). Fasting blood samples were taken and body mass index was measured pre- and post-intervention. Results : In CON, there was not significant change in all measured variables before and after the intervention period. Irisin increased ( P <0.01) by 0.64±0.27 mg/ml in HIIT group. Insulin decreased ( P <0.01) by 0.96±0.36 mg/dl while the blood lipid profile P = 0.78 cholesterol, P =0.14 TG, P =0.10 HDL, P =0.52 LDL, systolic blood pressure ( P = 0.51), dyastolic blood pressure ( P = 0.75), and BMI ( P = 0.87) were unaltered. Conclusion: The result of present study showed that high intensity interval swimming trainings is an effectual and time-efficient training way for increasing irisin, and it can lead to compensatory irisin increases in postmenopausal overweight women.

Background : Duchenne muscular dystrophy (DMD) is one of the most rampant x-linked recessive lethal genetic disease with prevalence of approximately 1 out of 3500-5000 newborn boys worldwide. DMD is mutations-induced in gene encoding dystrophin that prevent the production of the muscle isoform of dystrophin (Dp427m). Aim: This study aims to evaluate the impact of hydrotherapy on health-related quality of life and body composition changes, as well as how it affects on skeletal muscle strength in boys with DMD. Materials and Methods:  Eight boys, ranging from 6 to 12 years old with DMD were enrolled in this study. The patients were randomly assigned to either a hydrotherapy group as the intervention group (Group 1; n=4) or a non-exercise group as the control group (Group 2; n=4), to receive 12 sessions of a hydrotherapy program. The patients were assessed for changes in muscle strength in the lower limbs and back, left and right quadriceps, left and right-hand grip, LBM, SMM, and general mobility and balance, before and after hydrotherapy. Results : Significant improvements in general mobility and balance were observed, along with a significant increase in muscle strength and lean body mass ( P <0.05). Conclusion : This study suggests that hydrotherapy with a precise protocol of low to moderate intensity can improve general mobility and balance, increase muscle strength in the lower limbs and back, left and right quadriceps, left and right-hand grip, and LBM in patients with DMD. The increase in strength is accompanied by increase in LBM, which not only has implications for function but also has much broader impacts on the health-related quality of life in patients.

Background: Taekwondo is a traditional Iranian martial art currently practiced in over 206 countries around the world. Aim: The present study aims to provide fundamental information on injuries in Iranian elite Taekwondo athletes. Materials and Methods: A total of 200 Iran Taekwondo national team athletes (means±standard deviations: Age: 28.8±10.7 years, Height: 175.7±9.2 cm, Weight: 69±14.7 kg) participated in this retrospective study. The data was collected based on the injury surveillance system during 2021. The questionnaire included personal information and Taekwondo-related injuries information. Data was illustrated using descriptive methods and was analyzed using the Chi-Square test ( P <0.05). Results: The overall injury occurred during training was more than competition ( P <0.05). The occurrence of acute injury was higher than chronic ( P <0.05), and the most prevalent types of injuries were strain, rupture, and muscle spasm. The number of injuries that occurred in the lower extremity was higher than in other parts ( P <0.05), and the knee was the most vulnerable joint ( P <0.05). The most important cause of injuries was fatigue ( P <0.05). The non-contact injury was the most significant injury mechanism ( P <0.05). The severity of injury in Iranian elite Taekwondo athletes was high ( P <0.05). Conclusion: It can be concluded that injuries during training were more than competition, acute injury was more than chronic, strain was the most common type of injury, and the most vulnerable joint was the knee. Fatigue was the leading cause of injuries in elite Taekwondo athletes. So, in designing an injury prevention program, these factors should be considered.

Background : Digit ratio (2D:4D) is a marker of prenatal androgen exposure that has been associated with behavioral parameters. Individuals with low 2D:4D are more aggressive and tend to engage in more physical activity. Aim: We examined the relationship between 2D:4D and physical activity, sensation seeking and aggression in mature and immature boys. Materials and Methods: The study population consisted of Mazandaran male students aged 9 to 17 years in 2019-2020. The sample was 218 healthy, cluster randomly selected boys (13.77±2.4 y/o) from three schools with no health issues. 2D:4D digit ratio, physical activity, aggression, sensation seeking were measured. Pearson correlation analyzed variable associations. Significance was considered at P ≤0.05. Results : Low 2D:4D ratio was associated with higher physical activity (r≈-0.27), sensation seeking (r≈-0.3), and aggression (r≈-0.21), during childhood and adolescence ( P <0.05). These relationships among right and left hand 2D:4D ratios with physical activity and sensation seeking remained consistent across maturity levels ( P <0.05). Only immature boys had a significant association between 2D:4D ratios and aggression (r≈-0.29, P <0.05). Physical activity was positively associated with sensation seeking (r≈0.25, P <0.05), but not aggression in mature and immature boys. Conclusion : Prenatal testosterone organizes boys' physical activity and behavioral parameters, influencing the later development of sensation-seeking and aggression and greater participation in physical activity. The study has limitations such as a small sample size and a self-report method for assessing aggression. Future research should focus on behavioral observation methods with larger sample sizes.

Background: Drop landing is one of the tasks performed in many sports skills. Lower limb injuries have the highest prevalence in sports where jump landing is repeated frequently. One of the most common landing injuries is an anterior cruciate ligament (ACL) tear, which increases knee valgus and may contribute to an increased risk of ACL injury in athletes. In this situation, fatigue is one of the components that can affect various parameters of the landing task. Aim: The purpose of this study was to investigate and compare the acute and delayed effects of fatigue on the time to stability (TTS) of female gymnasts with and without dynamic knee valgus (DKV) during the landing task. Materials and Methods: In this semi-experimental study with a pretest-posttest design, 42 female gymnasts were selected through purposive and available sampling and divided into two groups of 21: a control group without DKV and an experimental group with DKV. The TTS in these individuals was measured before, after, and 24 hours after the fatigue protocol using the Kistler force plate device. The data was analyzed using SPSS software and statistical methods of analysis of covariance with repeated measures at a significance level of P ≥0.05. Results: According to the findings of this study, it showed that there is a significant difference in the variable of TTS in three time periods (before, after, 24 hours after fatigue) in the control and experimental groups ( P = 0.026). Conclusion: The results of the present study showed that plyometrics on the TTS are significantly different between people with DKV and without DKV, and people with DKV are necessarily at a greater risk of injury during landing tasks.