Independent and Combined Effects of Exercise and Dietary Calcium and Phosphorus on Bone.

bone mass;bone strength;dietary calcium;exercise;Biomedical Engineering;Physiology;Engineering;Health Sciences;Biomedical Engineering

Friedman, Michael AndrewZernicke, Ronald F. ;

University of Michigan

关键词: bone mass;    bone strength;    dietary calcium;    exercise;    Biomedical Engineering;    Physiology;    Engineering;    Health Sciences;    Biomedical Engineering;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/113376/friedmma_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Bone fractures are costly injuries that are becoming more prevalent as the population ages.Increased fracture risk is often associated with decreased bone mass.Exercise is an intervention that can reduce fracture risk by increasing bone mass, tissue quality, and strength.Early in exercise programs, bone favors increasing tissue quality over increasing bone mass and strength, potentially increasing fracture risk.Exercise causes an increased demand for dietary minerals required to increase bone mass.Combining exercise with a mineral-supplemented diet may allow maintenance of increases in both tissue quality and bone mass early in an exercise program.This could lead to greater long-term increases in bone mass or greater rate of bone growth to reach peak bone mass.It was hypothesized that combining exercise with a calcium- and phosphorus-supplemented diet would increase bone mass and mineralization over exercise with a standard diet in adult mice.Male, 4-month old mice performed daily treadmill exercise and were given either a standard or mineral-supplemented diet.Exercised mice taking a mineral-supplemented diet had greater cortical and trabecular bone mass after 3-4 weeks, compared to exercised mice on a standard diet.Greater bone mass was maintained after 8 weeks of treatment, as well as after an additional 8 weeks of non-exercise.Mice on the combined diet and exercise treatmentshad greater cortical bone mass and structural-level strength than non-exercised mice on the supplemented diet after 8 weeks.All mice on the supplemented diet achieved the same peak bone mass and bone strength, and exercise allowed these mice to reach their peaks in less time.Exercise increases mineral demand to increase bone mass and tissue quality.This work suggests standard dietary amounts of minerals are insufficient to maximize benefits from exercise.Increasing dietary mineral consumption with exercise can lead to greater bone mass and bone strength than exercise on a standard diet.Recommended values for dietary nutrients are determined based on non-exercise conditions, but this work suggests different nutrient amounts may be required for optimal bone health to meet different demands from exercise.