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Objective To evaluate the accuracy of the Yale Physical Activity Survey (YPAS) for older adults. Design Fourteen-week strictly controlled diet study. Subjects/Setting Eleven men and 17 women, age range 55 to 78 years, spent 10 weeks in an outpatient setting and 4 weeks in an inpatient setting at the General Clinical Research Center, Noll Physiological Research Center, The Pennsylvania State University, University Park. Intervention Subjects were provided dietary energy to maintain body weight within [+ or -]0.5 kg of baseline weight. The daily menus contained 0.8 g protein per kilogram body weight and nonprotein energy as 60% carbohydrate and 40% fat. Main Outcome Measures Metabolizable energy intake (MEI) was measured at week 14 from the gross energy contents of food, urine, and feces, with corrections for any body composition changes during the last 6 weeks of weight maintenance. Resting energy expenditure (REE) was determined using indirect calorimetry. The thermic effect of feeding (TEF) was estimated to be 10% of the MEI. The energy expenditure due to physical activity (EEPA) was derived by the formula: EEPA = MEI - REE - TEF. This value was compared with the EEPA estimated from the YPAS. Statistical Analyses Performed Two-factor analysis of variance with repeated measures and paired t tests. Results At week 14, after a minimum of 6 weeks of sustained weight stability, the derived EEPA was not different from that estimated using the YPAS for the men and the men and women combined, while the YPAS estimate was more than the measured mean value for the women (P<.05). There was wide variability in the accuracy of the EEPA prediction for individual subjects (range = -637 to 794 kcal). Applications/Conclusions The YPAS may be used, with caution, to estimate the EEPA for groups of older individuals, and may provide inaccurate estimates of the EEPA in older individuals. J Am Diet Assoc. 2004;104:1251-1257.

Objective To test the hypothesis that older men who consumed a vegetarian (lacto-ovo) diet would develop a lower iron status compared with older men who consumed a beef-containing diet during a period of resistive training (RT). Design Experimental, repeated measures study. Subjects Twenty-one healthy men aged 59 to 78 years, with a BMI range of 24 to 33 kg/[m.sup.2], completed the study. Intervention All men consumed a vegetarian diet for 2 weeks (baseline). After this, the men were randomly assigned to one of two dietary groups. Eleven men consumed a beef-containing diet, and 10 men continued to consume a vegetarian diet for 12 weeks. During this time all subjects participated in RT three days per week, designated as RT1 to RT12. Main outcome measures Serum ferritin and serum iron concentrations, transferrin saturation, transferrin receptor, total iron binding capacity, and selected hematological variables, as well as selected nutrient intakes and estimated iron bioavailability from three-day diet records, were determined at baseline, RT5, and RT12. Statistical analyses A general linear model repeated-measures ANOVA was used to examine the effects of group, time, and groupXtime interactions for iron status and dietary data. Results Total iron intake was not different between the two groups; however, the beef group had a three to four times greater intake of bioavailable iron (P Applications/Conclusions Older men who consume a beef-containing, higher-bioavailable-iron diet, compared with a vegetarian, lower-bioavailable-iron diet, have an increased hematological profile during a 12-week period of RT. Older men who consume either a beef-containing or a vegetarian diet maintain a hematological profile within clinically normal limits during 12 weeks of RT. J Am Diet Assoc. 2002;103:594-601., In the absence of disease or blood loss, iron status is primarily controlled by dietary iron absorption (1,2), which is regulated by current iron stores and the iron bioavailability of [...]