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Background&Objective: Low back pain (LBP) is common in youth, although `associated with chronic pain in adults. The purpose of this study was to determine the prevalence and risk factors of LBP in school children age 11-14. Materials&Methods: A cross sectional study was carried out on school children aged 11-14 in north of Iran. Using random multistage sampling 5000 children were selected. Demographic, mechanical and lifestyle data as well as the prevalence and LBP characteristics were collected by a questionnaire. Data analysis was carried out using SPSS (version11) software. Results: Of the original sample, 4813 (96.2%) children returned the questionnaire. Point, last month, last 6 months and annual prevalence were 15%, 14.4%, 15.6%, and 17.4%, respectively. LBP was significantly correlated with age (p<0.05), lifting (p<0.05), position and duration of watching TV, doing homework and duration of exercise (p<0.05). Conclusion: The results indicated that the prevalence of LBP in school children is relatively high. Further studies evaluating the effect of different preventive strategies to reduce the prevalence of LBP in school children is strongly recommended.

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Background and Objective: Extensive exercise may be disrupting oxidant and antioxidant balance and cause the phenomenon of oxidative stress in human and decrease athletics performance. This study was done to determine the effect of coenzyme Q10 supplementation for two weeks on markers of lipid peroxidation in soccer player. Methods: In this queze – experimental study, 36 soccer players (mean age, 20.08±1.12 years, weight 63.28±1.65 kg and maximal oxygen uptake 53.12±0.98 ml per kg/bw) divided into three groups for 14 days and the desired experiment was done during this period of time. Soccer players in control group did not receive the supplements and exercise. Subjects in placebo group were received 5 mg/kg/bw aspartame capsules. Subjects in supplement group were received 5 mg/kg/bw of Ubiquinone-10. Soccer players also performed two 90-minute soccer matches with less than 48 hours. Blood samples 24 hours before and after the period were collected. Malondialdehyde (MDA), lactate dehydrogenase (LDH), creatine kinase (CK) and aspartate aminotransferase (AST) levels were measured. Results: Serum level of MDA and AST after two consecutive football matches was significantly increased in the placebo group in compared to supplementation and placebo groups (P<0.05). The serum levels of AST and MDA in supplementation group did not significantly increased when compared to control and placebo groups. Conclusion: Short-term supplementation of coenzyme Q10 before and during of the two consecutive soccer matches can prevent the elevation of lipid Peroxidation indeces.

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Background and Objective: The beta-catenin (β-catenin) and T-cell factor 1 (TCF1) genes play a crucial role in bone development and remodeling. This study was conducted to determine the effect of combined resistance-aerobic exercise training on the Wnt/β-catenin signaling pathway and bone remodeling in a rat model of aging.
Methods: In this experimental study, 16 aged male Wistar rats (22 months old, weighing approximately 300–350 g) were randomly assigned to two groups: Control and training (n = 8 per group). Additionally, 8 young male rats (3 months old, weighing approximately 190–230 g) were included as a young control group. The training program consisted of eight weeks of combined resistance-aerobic exercise training program, with five sessions per week. Forty-eight hours after the final training session, the rats were anesthetized via intraperitoneal injection of ketamine and xylazine and subsequently sacrificed. Femoral bone tissue samples were isolated under sterile conditions. The expression levels of the target genes were evaluated using the real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) method.
Results: Following eight weeks of combined resistance-aerobic exercise training, a statistically significant increase was observed in the expression of β-catenin and TCF1 genes compared to the aged group (P<0.05). Specifically, the expression levels of β-catenin and TCF1 genes in the aged training group demonstrated a significant statistical increase compared to the aged control group (P<0.05).
Conclusion: Performing combined resistance-aerobic exercise training for eight weeks resulted in a significant increase in the expression of β-catenin and TCF1 genes within the bone tissue of aged rats.