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Background: Few studies have compared long-term moderate-intensity aerobic versus light-resistance training on serial improvements in glucose tolerance in older people., Methods: Healthy, inactive older (74 +/- 5 [SD] years) women (N = 20) were randomized into either a high-volume, moderate-intensity aerobic (ATM, n = 12) or a lower-intensity resistance training (RTL, n = 8) group. Both groups exercised under supervision 4 times per week for 45- to 60-min sessions over 9 months. Measurements of plasma glucose, insulin, and free fatty acid (FFA) responses to an oral glucose tolerance test (OGTT) were performed at baseline and at 3, 6, and 9 months 48 hours after the last exercise session., Results: We observed significant improvements in 2-hour glucose concentrations at 3, 6, and 9 months among women in the RTL(152 +/- 42 vs 134 +/- 33 vs 134 +/- 24 vs 130 +/- 27 mg x dL-1; P < .05), but not the ATM(151 +/- 25 vs 156 +/- 37 vs 152 +/- 40 vs 155 +/- 39 mg x dL-1) group. These improvements were accompanied by an 18% (P < .07) decrease in basal FFA concentrations in the RTLgroup, whereas basal and 30-min FFA concentrations increased (P < .05) after training in the ATMgroup., Conclusions: These findings suggest that the net physiological benefits of exercise might have been blunted in the ATMgroup, owing to higher circulating levels of FFA, which might have temporarily interfered with insulin action.

The purpose of this analysis was to determine the longitudinal relation between physical activity and the trajectory of weight change in an older cohort (> or =65 years) living in New Haven, Connecticut, who participated in the Established Populations for the Epidemiologic Study of the Elderly between 1982 and 1994 (n=2,812). The authors hypothesized that body weight would decline over the follow-up and that physical activity would play an important role in minimizing weight loss over time. Physical activity and other covariables were self-reported at baseline, while body weight was self-reported annually over 12 years. Multivariable random effects regression demonstrated a curvilinear trajectory of weight loss per year with an accelerated loss at older ages. Baseline body weight was 155 (standard deviation, 30) pounds (70 (standard deviation, 14) kg) for those who survived the entire follow-up and was 153 (standard deviation, 32) pounds (70 (standard deviation, 15) kg) for those who did not. Each 1-unit increase in baseline total activity score minimized this aging-related weight loss, but this relation was most pronounced among those with chronic disease who did not survive the entire follow-up period (n=973; 0.15 pounds (0.07 kg) per year). These data suggest that, among frail older people, even modest levels of physical activity can attenuate the rate of aging- and disease-related weight loss.

Tactile acuity of 60 older subjects (> or = 65 years) and 19 younger subjects (18-28 years) was assessed by two-point gap thresholds at the upper and lower surfaces of the forefinger, at the upper and lower surfaces of the feet, and at the volar surface of the forearm. The older subjects were assigned to one of four groups of 15 subjects each, depending on reported lifetime habits of physical activity and smoking: (1) active smokers, (2) active nonsmokers, (3) inactive smokers, and (4) inactive nonsmokers. Peripheral blood flow was assessed at the forefinger, foot, and forearm by means of laser-Doppler imaging and skin temperature recordings, under resting conditions and during and after a 5-min exposure to mild cooling (28 degrees C). Consistent with previous studies, tactile acuity thresholds in the foot and finger averaged about 80% higher in the older subjects than in the younger subjects, but only about 22% higher in the forearm. Although the upper surface of the fingertip was more sensitive than the lower surface in both younger and older subjects, the age-related decline in tactile acuity was nearly identical on both sides of the finger and foot. The latter finding refutes the hypothesis that the larger effect of aging in the extremities results from greater physical wear and tear on the contact surfaces of the hands and feet. Self-reported lifetime histories of physical activity and smoking were not significantly associated with measures of cutaneous blood flow or tactile thresholds. Possible reasons for this lack of association are discussed, including the inherent limitations of testing only healthy older subjects, and the concept of "successful aging".

ObjectiveSedentary behaviors related to television (TV) viewing are associated with adiposity; however, few investigations have focused on South Asians, an ethnicity particularly vulnerable to metabolic perturbations. This study examined the relationships between TV viewing and adiposity in a cohort of middle-aged and older South Asians.MethodData were obtained from Mediators of Atherosclerosis in South Asians Living in America (MASALA) study (N = 906; mean age [standard deviation] = 55 [9.4] years, 46% women). TV viewing hours per week was assessed through questionnaire and classified into tertiles for analysis. Multivariate linear regression models were used to examine the associations between TV viewing and measures of adiposity and body composition including body mass index (BMI), waist circumference, pericardial fat volume, and visceral, subcutaneous, and inter-muscular fat area after adjusting for covariates including intentional exercise.ResultsParticipants who were women, older, with lower education levels, and living longer in the United States watched TV for longer periods of times. Duration of TV viewing was positively associated with BMI (p

Background This study examines the relationship between various domains of sedentary behavior and subsequent cognitive function to evaluate whether different sedentary activities have specific associations with future cognitive performance. Methods Data were from 1 261 older adults participating in the Health, Aging, and Body Composition (Health ABC) Study between 1999/2000 and 2006/2007. Total sitting time (hours/day), reading time (hours/week), and TV time (≤27/≥28 h/wk) were self-reported at baseline and 3 years later. At follow-up, cognitive function was evaluated using the Teng Mini-Mental State Examination (3MS) and the Digit Symbol Substitution Test (DSST). Multivariable linear regression modeling examined the independent associations of baseline sedentary behaviors and 3-year change in those behaviors with cognitive function scores at follow-up, adjusting for important covariables. Results Baseline total sitting time was positively associated with 3MS (β = 0.14 ± 0.07; p <.05) and DSST (β = 0.20 ± 0.10; p <.05) scores at follow-up, as was reading time (β = 0.09 ± 0.03; p <.05 for 3MS score and β = 0.14 ± 0.04; p < 0.01 for DSST score). Participants who increased their TV watching time over 3 years had a significantly lower 3MS score (β = −1.45 ± 0.71; p <.05) at follow-up, compared with those who maintained a low level of TV time (referent). These findings were independent of age, sex, race, education level, health status, depressive symptoms, and physical activity. Conclusion Some types of sedentary behavior may have benefits for cognitive function in older age, thus highlighting the importance of measuring different domains of sitting time. [ABSTRACT FROM AUTHOR]

Background: Little attention has been paid to the study of transient growth hormone (GH) responses to exercise in older women. We determined the effect of a single bout of exercise on GH in fit and unfit older (age 55 to 81 y; n = 19) and younger (age 18 to 25 y; n = 19) women. Methods: Exercise consisted of five 15-min intervals of treadmill exercise at 75% VO2peak. Blood samples were taken before, during, and following exercise for determination of plasma GH and insulin concentrations.   Results: GH responses to exercise were attenuated in older compared with younger women (P < 0.01); however, these age differences were minimized in older age by fitness level. Adjusted area under the curve for GH was 5.50 and 1.76 mg/L · 102 for fit and unfit older women (P < 0.01), and 8.46 and 8.46 mg/L · 102 for fit and unfit younger women. Conclusions: Low levels of cardiorespiratory fitness in older women may require a greater relative exercise stimulus to augment meaningful GH responses. [ABSTRACT FROM AUTHOR]

Physical activity offers one of the greatest opportunities for people to extend years of active independent life and reduce functional limitations. The article identifies key practices for promoting physical activity in older adults, with a focus on those with chronic disease or low fitness and those with low levels of physical activity. Key practices identified: (a) A multidimensional activity program that includes endurance, strength, balance, and flexibility training is optimal for health and functional benefits; (b) principles of behavior change including social support, self-efficacy, active choices, health contracts, assurances of safety, and positive reinforcement enhance adherence; (c) manage risk by beginning at low intensity but gradually increasing to moderate physical activity, which has a better risk:benefit ratio and should be the goal for older adults; (d) an emergency procedure plan is prudent for community-based programs; and (e) monitoring aerobic intensity is important for progression and motivation. Selected content review of physical activity programming from major organizations and institutions is provided. [ABSTRACT FROM AUTHOR]

Objectives: Assessing aging muscle through estimates of muscle heterogeneity may overcome some of the limitations of grayscale analyses. The objectives of this study included determining statistical model parameters that characterize muscle echogenicity and are associated with strength in younger and older participants. Methods: Thirty‐three community‐dwelling participants were assigned to younger and older groups. Quantitative B‐mode ultrasound scanning of the rectus femoris and isometric grip strength testing were completed. Shape or dispersion parameters from negative binomial distribution, Nakagami, gamma, and gamma mixture models were fitted to the grayscale histograms. Results: The mean ages ± SDs of the younger and older groups were 24.0 ± 2.3 and 65.1 ± 6.5 years, respectively. Statistical model shape and dispersion parameters for the grayscale histograms significantly differed between the younger and older participants (P = .002–.006). Among all of the statistical models considered, the gamma mixture model showed the best fit with the grayscale histograms (χ2 goodness of fit = 62), whereas the Nakagami distribution displayed the poorest fit (χ2 goodness of fit = 2595). Grayscale values were significantly associated with peak grip strength force in younger adult participants (R2 = 0.36; P < .008). However, the negative binomial dispersion parameter k (adjusted R2 = 0.70; P < .001) and gamma shape parameter α (adjusted R2 = 0.68; P < .01) showed the highest associations with peak grip strength force in older adult participants. Conclusions: The negative binomial dispersion parameter k and the gamma shape parameter α have clinical relevance for the assessment of age‐related muscle changes. Statistical models of muscle heterogeneity may characterize the association between muscle tissue composition estimates and strength better than grayscale measures in samples of community‐dwelling older adults. [ABSTRACT FROM AUTHOR]

Supplemental digital content is available in the text. Purpose: To review and update the evidence of the relationship between physical activity, risk of fall-related injury, and physical function in community-dwelling older people that was presented in the 2018 Physical Activity Guidelines Advisory Committee Scientific Report (PAGAC Report). Methods: Duplicate independent screenings of 1415 systematic reviews and meta-analyses published between 2006 and 2016 identified from PubMed®, Cochrane Library, and CINAHL databases yielded 111 articles used for the PAGAC Report. The PAGAC Aging Subcommittee members graded scientific evidence strength based upon a five-criteria rubric and assigned one of four grades: strong, moderate, limited, or not assignable. An updated search of 368 articles published between January 2017 and March 2018 yielded 35 additional pertinent articles. Results: Strong evidence demonstrated that physical activity reduced the risk of fall-related injuries by 32% to 40%, including severe falls requiring medical care or hospitalization. Strong evidence also supported that physical activity improved physical function and reduced the risk of age-related loss of physical function in an inverse graded manner among the general aging population, and improved physical function in older people with frailty and with Parkinson's disease. Aerobic, muscle-strengthening, and/or multicomponent physical activity programs elicited the largest improvements in physical function in these same populations. Moderate evidence indicated that for older adults who sustained a hip fracture or stroke, extended exercise programs and mobility-oriented physical activity improved physical function. Conclusions: Regular physical activity effectively helps older adults improve or delay the loss of physical function and mobility while reducing the risk of fall-related injuries. These important public health benefits underscore the importance of physical activity among older adults, especially those living with declining physical function and chronic health conditions. [ABSTRACT FROM AUTHOR]

The cross-sectional relationship between physical activity, physical fitness, and measures of resting hemodynamic function and adiposity was examined in 11 women and 14 men, all of whom were in good health (M age = 69.3 yrs). Resting diastolic blood pressure (DBP) differed significantly by quartiles of both weekly energy expenditure and estimated VO2max. Subjects whose energy expenditure was above the 50th percentile had significantly lower DBP than Less active subjects, independent of age, gender, and VO2max, whereas those above the 75th percentile of VO2max had lower DBP and mean arterial pressure compared to less fit subjects, independent of age, gender, and weekly energy expenditure. There were no significant differences in the body mass index or percent body fat by quartile of weekly energy expenditure or estimated VO2max in the multivariable analysis. Mean waist- to-hip ratio (WHR) differed by level of weekly energy expenditure, independent of age, gender, and VO2max; individuals who reported a threshold of energy expenditure >&mn;6,099 kcal/wk had less relative abdominal fat than those reporting less activity. There were no significant independent differences in mean WHR or the central-to-peripheral skinfold ratio between quartiles of VO2max. [ABSTRACT FROM AUTHOR]

The article discusses the impact of sarcopenia on African American veterans and the healthcare system of the U.S. Veterans Health Administration (VHA). Topics discussed include the prevalence of sarcopenia in the U.S., assessment of lean body mass (LBM) as part of the diagnosis of sarcopenia, and categories of sarcopenia based on body composition, causative factors and stages of severity.

Describes the change in patterns of habitual physical activity in aging and the relationship of such changes to physical function and selected chronic diseases. Demographics of physical activity in older people; Determinants of physical activity; Level of exercise necessary and sufficient to achieve health benefits.

An introduction is presented in which the editor discusses various reports published within the issue on topics including the model of successful aging, the sex and age differences on a successful aging, and the relationship between stress and glycemic control in older people.