Purpose Verify the influences of physical activity level, nutritional status and screen habits on the prevalence of back pain in Brazilian students. Methods The sample consisted of 577 schoolchildren (female = 274; male = 303) aged between 10 and 16 years old, regularly enrolled in the 6 th grade of elementary school living in the metropolitan area of the Alto Tietê of the state of São Paulo, Brazil. The prevalence, intensity and frequency of pain was verified with the Back Pain Assessment Instrument. The usual practice of physical activity was verified with the Physical Activity Questionnaire for Older Children/Adolescent. Nutritional status was analyzed using Body Mass Index. Screen habits were obtained through a previously structured questionnaire. Results The Chi-square test indicated that pain complaint and its prevalence in the cervical region are significantly higher in females (p < 0.05). The multiple logistic regression test revealed that watching television influences the prevalence of cervical pain and that the use of more than one screen increases the occurrence of low back pain in male students (p < 0.05). Conclusion Female students were the most affected by back pain complain, especially in the cervical region. However, factors associated with the prevalence of back pain were found only in males.

No abstract

Aging is often accompanied by cognitive decline, memory impairment, and an increased susceptibility to neurodegenerative disorders. Although the physiological processes of aging are not fully understood, these age-related changes have been interpreted by means of various cellular and molecular theories. Among these theories, alterations in the intracellular signaling pathways associated with cell growth, proliferation, and survival have been highlighted. Based on these observations and on recent evidence showing the beneficial effects of exercise on cognitive function in the elderly, we investigated the cell signaling pathways in the hippocampal formation of middle-aged rats (18 months old) submitted to treadmill exercise over 10 days. To do this, we evaluated the hippocampal activation of intracellular signaling proteins linked to cell growth, proliferation, and survival, such as Akt, mTOR, p70S6K, ERK, CREB, and p38. We also explored the cognitive performance (inhibitory avoidance) of middle-aged rats. It was found that physical exercise reduces ERK and p38 activation in the hippocampal formation of aged rats, when compared to the control group. The hippocampal activation and expression of Akt, mTOR, p70S6K, and CREB were not statistically different between the groups. It was also observed that aged rats from the exercise group exhibited better cognitive performance in the inhibitory avoidance task (aversive memory) than aged rats from the control group. Our results indicate that physical exercise reduces intracellular signaling pathways linked to inflammation and cell death (i.e., ERK and p38) and improves memory in middle-aged rats.

The training periodization is not something trivial and simplistic, on the contrary, in addition to the technical and practical knowledge about the sport in question, it is essential for the coach to have a solid knowledge of the general principles that govern training. In this case, we can point out the principle of biological individuality, adaptation, overload, continuity, volume-intensity interdependence and specificity. Such principles should not be seen in isolation, instead, the coach should see the close relationship established in each of them throughout training. This requires a careful and intentional manipulation of these principles throughout the micro and mesocycles in the most varied phases and periods of the periodization macrocycle. This intervention, when assertive, will not only allow the evolution and maintenance of the athlete's performance, as well as help in the preservation of their physical well-being, which will have repercussions on their general state of health. Thus, this article aims, through a narrative review based on the classic literature of reference, to discuss the main concepts and principles of sports training.

No abstract