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Objective

To examine the associations of resistance exercise, independent of and combined with aerobic exercise, with the risk of development of hypercholesterolemia in men.

Patients and Methods

This study used data from the Aerobics Center Longitudinal Study, which is a cohort examining the associations of clinical and lifestyle factors with the development of chronic diseases and mortality. Participants received extensive preventive medical examinations at the Cooper Clinic in Dallas, Texas, between January 1, 1987, and December 31, 2006. A total of 7317 men aged 18 to 83 years (mean age, 46 years) without hypercholesterolemia at baseline were included. Frequency (times per week) and total amount (min/wk) of resistance and aerobic exercise were determined by self-report. Hypercholesterolemia was defined as a total cholesterol level of 240 mg/dL or higher or physician diagnosis.

Results

During a median (interquartile range) follow-up of 4 (2 to 7) years, hypercholesterolemia developed in 1430 of the 7317 men (20%). Individuals meeting the resistance exercise guidelines (≥2 d/wk) had a 13% lower risk of development of hypercholesterolemia (hazard ratio [HR], 0.87; 95% CI, 0.76-0.99; P=.04) after adjustment for general characteristics, lifestyle factors, and aerobic exercise. In addition, less than 1 h/wk and 2 sessions per week of resistance exercise were associated with 32% and 31% lower risks of hypercholesterolemia (HR, 0.68; 95% CI, 0.54-0.86; P=.001; and HR, 0.69; 95% CI, 0.54-0.88; P=.003), respectively, compared with no resistance exercise. Higher levels of resistance exercise did not provide benefits. Meeting both resistance and aerobic exercise guidelines (≥500 metabolic equivalent task min/wk) lowered the risk of development of hypercholesterolemia by 21% (HR, 0.79; 95% CI, 0.68-0.91; P=.002). compared with meeting none of the guidelines.

Conclusion

Compared with no resistance exercise, less than 1 h/wk of resistance exercise, independent of aerobic exercise, is associated with a significantly lower risk of development of hypercholesterolemia in men (P=.001). However, the lowest risk of hypercholesterolemia was found at 58 min/wk of resistance exercise. This finding suggests that resistance exercise should be encouraged to prevent hypercholesterolemia in men. However, future studies with a more rigorous analysis including major potential confounders (eg, diet, medications) are warranted.  相似文献   
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We examined associations between physical fitness and risk factors for coronary heart disease in healthy women ages 18-65 years. Physical fitness was objectively determined by the duration of a maximal treadmill exercise test. Six physical fitness categories (very poor to superior), specific within 10-year age increments, were established. Mean risk factor levels varied across categories, but so did potential confounders such as age and weight. Multiple linear regression modeling was used to control for the effects of age, weight and year of exam on coronary risk factors. After adjustment, physical fitness was independently associated with triglycerides (p less than 0.001), high-density lipoprotein cholesterol (HDL-C) (p less than or equal to 0.001), total cholesterol/HDL-C ratio (p less than or equal to 0.001), blood pressure (p less than or equal to 0.001) and cigarette smoking (p less than or equal to 0.001).  相似文献   
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Loss-of-function mutations in the progranulin (GRN) gene are a common cause of autosomal dominant frontotemporal lobar degeneration, a fatal and progressive neurodegenerative disorder common in people less than 65 years of age. In the brain, progranulin is expressed in multiple regions at varying levels, and has been hypothesized to play a neuroprotective or neurotrophic role. Four neurotoxic agents were injected in vivo into constitutive progranulin knockout (Grn−/−) mice and their wild-type (Grn+/+) counterparts to assess neuronal sensitivity to toxic stress. Administration of 3-nitropropionic acid, quinolinic acid, kainic acid, and pilocarpine induced robust and measurable neuronal cell death in affected brain regions, but no differential cell death was observed between Grn+/+ and Grn−/− mice. Thus, constitutive progranulin knockout mice do not have increased sensitivity to neuronal cell death induced by the acute chemical models of neuronal injury used in this study.  相似文献   
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