Effect of leucine supplementation on fat free mass with prolonged hypoxic exposure during a 13-day trek to Everest Base Camp: a double-blind randomized study.

Loss of body weight and fat-free mass (FFM) are commonly noted with prolonged exposure to hypobaric hypoxia. Recent evidence suggests protein supplementation, specifically leucine, may potentially attenuate loss of FFM in subcaloric conditions during normoxia. The purpose of this study was to determine if leucine supplementation would prevent the loss of FFM in subcaloric conditions during prolonged hypoxia.

Efficacy and safety of protein supplements for U.S. Armed Forces personnel: consensus statement.

To provide evidence-based guidance regarding the efficacy and safety of dietary protein supplement (PS) use by members of the U.S. Armed Forces, a panel of internationally recognized experts in the fields of protein metabolism and dietary supplement research was convened by the Department of Defense Center Alliance for Dietary Supplement Research and the U.

Bison meat has a lower atherogenic risk than beef in healthy men.

The rearing method of bison and the nutrient content of the meat may make bison a healthier alternative to beef. We hypothesized that the acute and chronic effects of bison consumption, in comparison to beef, will result in a less perturbed blood lipid panel and a reduced inflammatory and oxidative stress response which will minimize the detrimental effect on vascular function. A double-blind, cross-over randomized trial was employed to examine the consequence of a single 12 oz serving (n = 14) and 7 weeks of chronic consumption (n = 10) (12 oz/d, 6 d/wk) of each meat.

A comparison of subjective and objective measures of physical exertion.

Better methods are needed to improve validity and reliability of physical activity (PA) assessment instruments. The purpose of this study was to compare individual's Borg's Rate of Perceived Exertion (RPE) scores to GT1M ActiGraph accelerometer output, with the aim to better understand estimates of perceived exertion for exercise prescription. Adults were recruited (n = 117) from Utah, with 43.

Musculoskeletal abnormalities of the tibia in juvenile rheumatoid arthritis.

Objective: To characterize local bone geometry, density, and strength, using peripheral quantitative computed tomography (pQCT), compared with general bone characteristics as measured using dual x-ray absorptiometry (DXA), and to assess their relationship to disease-related factors in children with juvenile rheumatoid arthritis (JRA).

Methods: Forty-eight children ages 4-18 years with JRA (17 pauciarticular, 23 polyarticular, 8 systemic) were compared with age-matched healthy controls (n = 266). Measurements included cortical and trabecular bone geometry, density, and strength at the distal and midshaft tibia determined by pQCT, and whole-body, lumbar spine, and femoral neck measurements by DXA.

Association of adipose and red blood cell lipids with severity of dominant Stargardt macular dystrophy (STGD3) secondary to an ELOVL4 mutation.

Objective: To determine whether adipose and red blood cell membrane lipids, particularly long-chain polyunsaturated fatty acids such as docosahexaenoic acid and eicosapentaenoic acid, are significantly correlated with phenotype in a family with autosomal dominant Stargardt macular dystrophy (gene locus STGD3). A mutation in the ELOVL4 gene is responsible for the macular dystrophy in this family, and its disease-causing mechanism may be its possible involvement in fatty acid elongation in the retina.

Methods: The subjects in this study included 18 adult family members known to have a 2-base pair deletion in the ELOVL4 gene.

Bone mineral acquisition in adolescents with type 1 diabetes.

Objective: To track bone mineral acquisition in adolescents with type 1 diabetes (DM).

Study Design: Subjects were adolescents, ages 12 to 18 years, with DM (n=42) and a healthy regional reference (n=199). Measurements of tibia bone characteristics by peripheral quantitative computed tomography (pQCT) and spine and whole body (WB) by dual-energy x-ray absorptiometry (DEXA), anthropometrics, and lifestyle questionnaires were obtained during a 12-month period.

Food for high-altitude expeditions: Pugh got it right in 1954--a commentary on the report by L.G.C.E. Pugh: "Himalayan rations with special reference to the 1953 expedition to Mount Everest".

An examination of the nutritional recommendations at altitude by L.G.C.

Dietary modification and moderate antioxidant supplementation differentially affect serum carotenoids, antioxidant levels and markers of oxidative stress in older humans.

Oxidative stress is thought to be a factor in the progression of chronic diseases, and even the aging process itself. We examined the effect of two moderate vitamin, mineral and phytochemical supplements and a dietary intervention on markers of oxidative stress and antioxidant status in older humans. Subjects (n = 60, 65-85 y old) were enrolled in a 5-wk, double-blind, placebo-controlled study.

Lack of effect of Rhodiola or oxygenated water supplementation on hypoxemia and oxidative stress.

Objective: This study investigated the effects of 2 potentially "oxygen promoting" dietary supplements on hypoxia and oxidative stress at a simulated altitude of 4600 m.

Methods: Fifteen volunteers (ages 20-33) received 3 separate 60-minute hypoxic exposures by breathing 13.6% oxygen at an ambient barometric pressure of 633 mm Hg (simulating the partial pressure of oxygen at 4600 m elevation).