The US population over the age of 65 years is growing rapidly, with elderly women outnumbering men by 50 percent. Studies show that aging is often accompanied by reduced energy intake, inadequate nutrition, and the loss of lean body mass with a subsequent increase in body fat, as well as the tendency towards inactivity. An increased level of physical activity elevates energy needs, which can lead to increased energy and nutrient intake, and has been shown to aid in the maintenance of lean body mass and the reduction of body fat. Positive health outcomes for seniors depends partly on a clearer understanding of the interrelationships between physical activity, diet, and body composition. The purpose of this study was to determine whether higher overall levels of physical activity among elderly women, were related to higher energy intake, nutrient adequacy, and less body fat, and to what extent age affected these associations. Sixty-three elderly women (aged 65-98 years) volunteers completed a three part study spanning 14 weeks. Mean level of physical activity (MLPA) and mean nutrient intakes were estimated using nine self-reported days of records, three predetermined days from each of three recording periods. MLPA was determined from self-reported hours spent in five physical activity categories (resting, very light, light, moderate, and heavy), multiplied by corresponding weighted factors of intensity (1.0, 1.5, 2.5, 5.0, 7.0, respectively). Nutrient analyses for seven vitamins (vitamin A, vitamin C, thiamin, riboflavin, niacin, vitamin B6, vitamin B12) and three minerals (calcium, iron, and zinc) were done using the Food Processor II computer software. A mean adequacy ratio (MAR) was calculated for each subject as the average percent of the RDA for intakes of all 10 nutrients. Body composition assessment included triplicate measures of: height and weight from which body mass index (BMI) was determined; waist-to-hip ratio (WHR); and an estimation of percent body fat (PBF) from the sum of four skinfolds (triceps, biceps, subscapular, suprailiac). It was determined that MLPA was not directly related to energy intake, nutrient adequacy, or the three body composition parameters. However, the correlation coefficients between MLPA and energy intake, mean adequacy ratio, and percent RDA for 8 of the 10 nutrients were positive, and the correlation coefficients between MLPA and all three body fatness measures were negative, as was expected. The small coefficient of variability of MLPA limited its discriminating power in determining associations with energy intake, nutrient adequacy, and body composition. Backward stepwise regression models were conducted to distinguish potential confounding effects of age, education, and MLPA on the variables kcal/day, kcal/kg/day, MAR, BMI, WHR, and PBF. Age was found to account for the largest portion of the variations, and was greater than the contribution of MLPA for all of these variables, except in the case of kcal/kg/day. When the subjects were divided into young-old (65-74 yr) and old-old (75-98 yr) subgroups, the younger compared to the older women were found to be more active as measured by MLPA (p=.02), explained by their engaging in more light activities of daily living (p=.04). The young-old compared to the old-old women consumed more kcalories/day (p=.01), and had a higher MAR score (p=.00). The nutrient densities of the two groups' diets were not significantly different. The younger women had slightly lower BMI, WHR, and PBF values. This study revealed age, rather than MLPA, was a better predictor of some parameters of diet adequacy and body fatness among this sample of elderly women. In addition, consistently higher levels of physical activity and greater dietary adequacy and was found among the younger compared to the older portions of this sample of senior women, suggesting that nutrition intervention programs for the elderly should encourage daily activeness as a strategy to maintain or improve dietary adequacy with advancing age. / Graduation date: 1993

The percentage of the American population who are 65 years old or older is rapidly increasing, especially the proportion of women. It is becoming crucial to encourage lifestyle behaviors that will enable senior women to remain in optimal health. Following the 1990 Dietary Guidelines' recommendations to limit fat intake and consume adequate amounts of dietary fiber has been shown to positively impact longevity and health status in the elderly by decreasing risk factors for chronic diseases. An expected outcome of engaging in regular exercise is a reduction in body fat, which is also associated with a lowered incidence of several chronic illnesses. However, the literature clearly indicates that nutritional quality of the diet and involvement in regular exercise decrease with increasing age. There is evidence that, with the adoption of one health enhancing behavior, there is a greater tendency to engage in other health promoting behaviors, but little data exist on the healthseeking behaviors of older adults. The purpose of this study was to ascertain if there were identifiable differences between self-defined exercising and self-defined non-exercising elderly women with respect to their nutrient intake, food sources of dietary fat and fiber, dietary change behavior, and body composition parameters, considering their age and education and income levels. The objective was to determine whether those women who had consciously undertaken a regular exercise program would also have higher micronutrient intakes, make lower fat and higher fiber food choices, report having made more dietary changes in the direction of the 1990 Dietary Guidelines, and have leaner body compositions than those who had not undertaken such a program. Thirty-three elderly women self-reported exercisers (mean age 74.1 years) and 30 self-reported non-exercisers (mean age 71.3 years) were enrolled in a 14 week study. Exercisers were defined as those who reported having engaged in a regular program of planned exercise a minimum of 15 minutes per session, 2 times per week, for at least the last year, and non-exercisers were those who had not. They kept three, 7-day food records at 5 week intervals. Nutrient intake was estimated from 9 days of food records, 3 predetermined days from each recording period, using the Food Processor n software. Dietary intakes were analyzed for energy, macronutrients, dietary fiber, and selected micronutrients. Food sources of dietary fat and fiber were determined using a food categorization adapted from Popkin and coworkers (1989). Information concerning dietary change behavior, obtained from questionnaire responses, was compared between groups using chisquare tests. Body composition, assessed through repeat measurements during each dietary recording period, included determination of percent body fat through skinfolds, waist-to-hip-ratio and body mass index. Average 9-day nutrient intakes and anthropometric measures were compared between groups using t-tests or Mann- Whitney U tests. Both elderly women exercisers and non-exercisers had similar energy, macronutrient, and dietary fiber intakes based on 9-day means. Their total fat intakes, expressed in grams and as percentages of energy, were not significantly different. Both groups consumed a lower percentage of their daily kcalories as total fat (32%) compared with national surveys of women over 65 (36%). Exercisers consumed more total vitamin A (p=.03) and carotene (p=.00) than the non-exercising women. A great proportion of both groups did not meet 75 % of the Recommended Dietary Allowances for calcium and zinc. A larger proportion of the exercisers than the non-exercisers reported using lower fat cheese (p=.02) and green and yellow vegetables (p=.03), which partially explained their higher total vitamin A and carotene intakes. Exercisers obtained less of their total fat intake from lower fat milk (p=.02) and more of their fat intake from lower fat lunch meats (p=.04) than the non-exercisers. The categories of legumes (p=.02) and lower fiber vegetables (p=.05) supplied greater amounts of dietary fiber for the exercisers compared with the non-exercisers. When asked about dietary changes made over the past decade, a greater percentage of the exercisers than non-exercisers reported having decreased red meat intake (p=.05) and increased consumption of cereals (p=.05) and legumes (p=.00). Actual intake data showed that the legume food category contributed more dietary fiber to the diets of the exercisers than the non-exercisers (p=.02). No differences were found in body fat measures between the exercisers and non-exercisers. The lack of observed differences between the two groups reinforces what other researchers have found, that a large number of factors influence body composition, of which exercise is only one. More research is needed to distinguish the interactions of age, energy intake, and physical activity on the body fatness of elderly women, as well as the most accurate instruments for assessing body composition for this age group. Exercise participation among elderly women in this study appeared to be associated with several positive dietary behaviors. Elderly women exercisers compared to non-exercisers made food choices leading to higher total vitamin A and carotene intakes, and also reported making more changes in food consumption behaviors in the direction of current dietary recommendations. These observed outcomes provide support for designing health-promotion programs for elderly women which include both nutrition education and exercise components. / Graduation date: 1993