作者:Josiel Almeida de Avila
关键词:/
发表时间:2019
发表期刊:Rev Assoc Med Bras
证据类型:系统评价/Meta分析
Bone density is related to genetic, hormonal, nutritional, and environmental factors. Among the environmental factors, physical activity is identified as a major contributor to bone density gain during different periods of life, since the formation of bone is associated with the elastic compressive force of muscle contractions and weight support. Thus, activities that impose heavier loads on the bone structure cause more significant gains in bone density. Bone Mineral Density (BMD) can be analyzed using x-rays, neutron activation, absorptiometry dual-energy x-ray absorptiometry (DXA), and high-resolution magnetic resonance imaging. The first two techniques present a disadvantage because they expose the patient to a large amount of radiation. Currently, the most commonly used method for evaluating bone health is DXA, which estimates the content of the bone area, and is considered the gold standard to evaluate bone density. Furthermore, this technique has low cost and little exposure to ionizing radiation. According to the World Health Organization, cases of osteoporosis are expected to double by the year 20508. Currently, osteoporosis affects about 50% of women and 20% of men over the age of 50 years-old. The illnesses linked to bone health are dependent on inherent bone loss due to age, but they are also influenced by bone acquisitions that occur during adolescence and adult life. Studies have shown that resistance exercises, impact activities, and sports preserve bone health. Although many cross-sectional studies show that physical activity is related to BMD, longitudinal studies are still scarce. Thus, this systematic review aimed to determine how the variables of physical training (duration, volume, intensity, type of activity, and frequency of training) influence BMD evaluated by DXA in young adults.