Association between energy availability and physical activity in older adults

Can tailored home-delivered meal services alleviate self-rated frailty of the low-income older adults in Korea?

BACKGROUND/OBJECTIVES

This study aimed to examine whether the tailored home-delivered meal (HDM) services included nutrition counseling impacts alleviating self-rated frailty among low-income older adults in Korea.

SUBJECTS/METHODS

Pre- and post-test were implemented on May 27 and on November 25 in 2019 during 3 weeks, respectively, before and after the 6 months intervention program. Participants completed a questionnaire measuring frailty, malnutrition, food security, depression, and underlying diseases. Initially, 136 older adults were selected as participants for this study, they were recipients of a free meal program from 2 senior welfare centers in Seoul, the final sample size of those who completed the intervention program was 117 (female 70.9%, male 29.1%). Statistical analyses were conducted with IBM SPSS package program, paired t-test and χ2 test to validate the test.

RESULTS

There were statistically significant differences in the score of the Tilburg Frailty Indicator (TFI) before and after receiving the tailored HDM services (pre-test 9.46, post-test 2.8, P < 0.01). The differences in the score of TFI by 3 risk groups at the pre-test decreased as a result of receiving these services.

CONCLUSIONS

The tailored HDM services alleviated the self-rated frailty of low-income older adults with limited mobility in a community setting. Based on the positive outcomes this study could be applied to developing social services for aging in place.

Dual-task walking on real-world surfaces: Adaptive changes in walking speed, step width and step height in young and older adults

OBJECTIVES

Age-related changes in dual-task walking are well established, but research in this topic is based on evidence from laboratory rather than real-world studies. We investigated how dual-task walking on real-world surfaces affects young and older adults' gait characteristics and cognitive resource allocation.

METHOD

Sixteen young (aged 19-35, 12 female) and fifteen older adults (aged 70-85, 7 female) with no major neurological or musculoskeletal disorders walked at a self-selected speed on forty-metre outdoor paths that had asphalt or grass surface. They walked with or without a cognitive task (counting backwards). Cognitive task difficulty was individually adjusted at 80 % accuracy. Participants performed the three tasks in Single Task (ST Asphalt, ST Grass, ST Cognitive) and Dual Task context (DT Asphalt-Cognitive, DT Grass-Cognitive).

RESULTS

The two groups showed similar dual task effects in cognition and walking speed, both of which were slower when dual-task walking. Older adults' steps were wider overall but only young adults widened their step width when dual-task walking on grass compared to asphalt. Similarly, young adults' step height increased from single to dual-task walking when on grass, where older adults' did not.

DISCUSSION

The lack of adaptation of step width and height when dual-task walking may leave older adults vulnerable to tripping or falling in common real-world conditions, such as while walking on grass, gravel, or uneven city sidewalks. Considering this, the built environment should be made more accessible to facilitate older adults' safe walking.

Impact of mobility restrictions on active aging; cross-sectional associations and longitudinal changes parallel to COVID-19 restrictions

BACKGROUND

Meaningful activities can be done in or around home, but opportunities for participation and active aging decrease when moving in smaller areas. Active aging refers to having an active approach to life in line with one's goals, ability and opportunities. In adults over 75 years with different baseline neighborhood mobility levels, we studied active aging scores two years prior to and amid COVID-19, when governments restricted mobility of residents to slow the COVID-19 outbreak.

METHODS

AGNES cohort data were collected in 2017-2018 and spring 2020. Individuals were queried about their will, ability, and opportunity, and extent of doing 17 activities, and subsequently, item, composite and sub-scores of active aging were computed. Neighborhood mobility was assessed as frequency of moving in or beyond own neighborhood (limited, regular, daily=reference). Associations were studied using Generalized Linear Models (cross-sectionally, n = 1007) and General Estimating Equations (prospectively, n = 774).

RESULTS

Participants with limited baseline neighborhood mobility had lower active aging scores than those with daily mobility, but the decline over time was similar. Some item scores on opportunity to act and extent of doing, e.g. for making one's day more interesting and advancing matters of faith or worldview, were better retained amid COVID-19 by those with limited mobility, attenuating group differences.

CONCLUSIONS

Active aging scores were somewhat compromised in individuals with limited neighborhood mobility, but opportunities for and engagement in several activities seemed to be better retained amid COVID-19 than for those with daily mobility. Thus, active aging may be possible despite mobility restriction.

Walking energetics and fatigue are associated with physical activity in people with knee osteoarthritis

BACKGROUND

Aberrant biomechanics may influence osteoarthritis-associated physical activity limitations. Our purpose was to evaluate the association of walking energetics, fatigue, and fatigability on physical activity in people with knee osteoarthritis. We hypothesized that using increased energy for walking, experiencing more fatigue, or being more fatigable are associated with less activity, and that fatigue and fatigability mediate the relationships between walking energetics and physical activity.

METHODS

We tested our hypothesis in 30 people with knee osteoarthritis (age 58 ± 9 years, 10 Male/20 Female). Physical activity was assessed using the University of California Los Angeles score. We used a six-minute walk test to predict VO₂max. Next we used a portable oxygen exchange system to measure relative energy used (100 * VO₂rate/VO₂max) and VO₂cost during walking at preferred speeds. We used the Knee injury and Osteoarthritis Outcome Score subscale to quantify pain, and the Patient Reported Outcome Measurement Instrument System Fatigue survey and a treadmill-based fatigability test to assess fatigue and fatigability. Spearman correlations, regression, and mediation analysis were used to test our hypotheses.

FINDINGS

Greater energy used during walking, fatigue, and fatigability were all associated with lower physical activity (rho = -0.585 to -0.379, P = 0.001 to 0.043). These associations persisted when incorporating pain into the models. Fatigue and fatigability mediated the associations between walking energetics and physical activity.

INTERPRETATION

Walking energetics could be a useful target to promote physical activity in people with osteoarthritis. Further, the effect of walking energetics on physical activity may work through its impact on fatigability.

Association between walking energetics and fragmented physical activity in mid-to-late life

BACKGROUND

Physical activity becomes increasingly fragmented with age, which may be an early marker of functional decline. Energetic cost of walking and energy capacity are also linked with functional decline, but their associations with activity fragmentation, and the potential modifying roles of total daily physical activity and age, remains unclear.

METHODS

493 participants (50-93 years) from the Baltimore Longitudinal Study of Aging underwent measures of: energetic cost of usual-paced overground walking (ml/kg/m), energy demand during slow walking (ml/kg/min) on a treadmill (0.67 m/s, 0% grade),m/s, 0% grade), and average peak walking energy expenditure (ml/kg/min) during a fast-paced 400-m walk. A ratio of slow walking to peak walking energy expenditure ("cost-to-capacity ratio") was calculated. Activity fragmentation was quantified as an active-to-sedentary transition probability (ASTP) using Actiheart accelerometer data. Linear regression models with ASTP as the dependent variable were used to test whether poorer energy cost and capacity were associated with higher ASTP and whether the associations differed by daily physical activity or age.

RESULTS

After adjusting for demographics, body composition, comorbidities and daily physical activity, every 10% higher cost-to-capacity ratio was associated with 0.4% greater ASTP (p=0.005). This association was primarily driven by the least active participants (pinteraction=0.023). Peak walking energy expenditure was only associated with ASTP among participants aged ≥70 years.

CONCLUSIONS

Higher cost-to-capacity ratio and lower energy capacity may manifest as more fragmented physical activity, especially among those less active or aged ≥70 years. Future studies should examine whether an increasing cost-to-capacity ratio or declining energy capacity predicts subsequent activity fragmentation.

Walking energetics and abductor strength are associated with physical activity in older women with hip osteoarthritis

BACKGROUND

Osteoarthritis (OA) can hinder physical activity in older adults for reasons that are not fully understood. Functional barriers may exist such as reduced muscle strength around the affected joint, potentially affecting physical activity. Aging-associated declines in energy capacity may also be exacerbated by OA. These factors may work together to influence physical activity in people with OA.

RESEARCH QUESTION

Our objective was to evaluate the combined role of walking energetics and hip abductor strength on physical activity in older women with hip OA.

METHODS

We evaluated 30 women with moderately symptomatic hip OA (61 ± 10 yrs; 30.7 ± 4.9 kg/m²) in this cross-sectional observational study. We measured physical activity using the UCLA activity score and quantified activity frequency and intensity using accelerometers worn for seven days (7 ± 2 days). We used a portable oxygen exchange system to measure energy used during walking at preferred speeds (relative to total energy capacity assessed using a six-minute walk test) and a dynamometer to measure hip abductor strength. We used Pearson correlations and regression analysis to test our hypotheses.

RESULTS

Greater energy used during walking was associated with lower self-reported physical activity (R=-0.626, p < 0.001), more sedentary time (R = 0.567, p = 0.002), and less light activity time (R=-0.644, p < 0.001). Lower hip abductor strength was associated with lower self-reported physical activity (R = 0.406, p = 0.039). While there was no association between hip abductor strength and energy used during walking, together these variables predicted 55.5 % of the variance in self-reported physical activity.

SIGNIFICANCE

Results suggest intervention targets to promote physical activity in this population.

Association of Mitochondrial Function, Substrate Utilization, and Anaerobic Metabolism With Age-Related Perceived Fatigability

Previous work has shown that poorer mitochondrial function is associated with age-related perceived fatigability. However, whether glucose oxidation and anaerobic metabolism are intermediate factors underlying this association remains unclear. We examined the total cross-sectional association between mitochondrial function and perceived fatigability in 554 adults aged 22-99 years. Mitochondrial function was assessed by skeletal muscle oxidative capacity (kPCr) using 31P magnetic resonance spectroscopy. Perceived fatigability was measured by rating of perceived exertion after a 5-minute (0.67 m/s) treadmill walk. The intermediate role of glucose oxidation (measured by the rate of change of respiratory exchange ratio [RER change rate] during the 5-minute treadmill walk) and anaerobic metabolism (measured by ventilatory threshold [VeT] during a maximal treadmill test) was evaluated by examining their cross-sectional associations with kPCr and perceived exertion. For each 0.01/s lower kPCr, perceived fatigability was 0.47 points higher (p = .002). A 0.01/s lower kPCr was also associated with 8.3 L/min lower VeT (p < .001). Lower VeT was associated with higher fatigability at lower levels of kPCr but not at higher kPCr levels (β for interaction = 0.017, p = .002). kPCr and RER change rate were not significantly associated (p = .341), but a 0.01/min higher RER change rate was associated with 0.12-point higher fatigability (p = .001). Poorer mitochondrial function potentially contributes to higher perceived fatigability through higher glucose oxidation and higher anaerobic metabolism. Future studies to further explore the longitudinal mechanisms between these metabolic changes and fatigability are warranted.

Protein Intake and Frailty: A Matter of Quantity, Quality, and Timing

Frailty is a geriatric syndrome that refers to a state of reduced resiliency to stressful events that occurs in response to physiological and/or psychosocial detriments. Frailty is a predictor of poor prognosis, given that frail older adults are at higher risk of many adverse health-related events. Hence, the identification of potential strategies to prevent the development and progression of frailty is of extreme importance for avoiding its negative outcomes. An adequate protein consumption is advocated as a possible intervention for the management of frailty in older adults due to its effects on muscle mass and physical function. However, empirical evidence is still needed to support this proposition. On the other hand, substantial evidence from observational studies has provided important information on the association between frailty and dietary protein-related parameters. Here, we provide a narrative review of the current literature regarding the association between protein intake (amount (how much?), quality (what type?), and distribution across meals (when?)) and frailty-related parameters. The ultimate aim of this work is to offer practical, evidence-based indications to healthcare professionals responsible for the care of frail older adults.

Neighborhood Mobility and Unmet Physical Activity Need in Old Age: A 2-Year Follow-Up

BACKGROUND

Many older people report a willingness to increase outdoor physical activity (PA), but no opportunities for it, a situation termed as unmet PA need. The authors studied whether lower neighborhood mobility and PA precede the development of unmet PA need.

METHODS

Community-dwelling 75- to 90-year-old people (n = 700) were interviewed annually for 2 years. Unmet PA need, neighborhood mobility, and PA were self-reported. In addition, accelerometer-based step counts were assessed among a subgroup (n = 156).

RESULTS

Logistic regression analyses revealed that lower baseline neighborhood mobility (odds ratio 3.02, 95% confidence interval [1.86, 4.90] vs. daily) and PA (odds ratio 4.37, 95% confidence interval [2.62, 7.29] vs. high) were associated with the development of unmet PA need over 2 years. The participants with higher step counts had a lower risk for unmet PA need (odds ratio 0.68, 95% confidence interval, [0.54, 0.87]).

CONCLUSION

Maintaining higher PA levels and finding solutions for daily outdoor mobility, especially for those with declines in health, may protect from the development of unmet PA need.

The role of nutrition and physical activity in frailty: A review

Frailty is a clinical syndrome with a worldwide prevalence of 5-27% among those aged over 65 years. Frailty is characterised by loss of muscle strength and impaired physical function, and is associated with increased falls, hospitalisation and death. Nutritional deficiencies and low physical activity are common in this age group due to ill health, disability and reductions in enthusiasm, food intake and therefore, energy availability. Both low physical activity and inadequate dietary intake have a significant role to play in the onset and progression of frailty, primarily through bone and muscle health implications. Frailty is, however, preventable and reversible, and several interventions have been carried out to offset and reverse the condition. This article reports the recent evidence on the role of nutrition and physical activity in the pathogenesis of frailty and provides a critical review of previously implemented interventions focussed on physical activity and nutrition to prevent and reduce frailty among older adults.

Perceived Fatigability and Objective Physical Activity in Mid- to Late-Life

Background

Fatigability, defined as fatigue in relation to a standardized task, predicts functional decline in older adults independent of reported tiredness or energy level. Although the sensation of fatigue, tiredness, and energy level adversely affect physical activity (PA), the association between fatigability and objectively measured PA is unknown.

Methods

Participants in the Baltimore Longitudinal Study of Aging (n = 557, 50% women, aged 50-97 years) were instructed to wear an Actiheart accelerometer for 7 consecutive days in the free-living environment. Perceived fatigability was assessed using the Borg rating of perceived exertion (RPE) after 5 minutes of treadmill walking at 1.5 mph (0.67 m/s) and categorized as low (6-7 RPE), intermediate (8-9 RPE), and high (10+ RPE) fatigability. Time-of-day PA differences between fatigability groups were assessed using mixed-effects modeling.

Results

Total daily PA was 1.3% lower for every unit increment in perceived fatigability after adjusting for demographic, behavioral, and medical factors (p = .01). In time-of-day analyses, the high fatigability group was less active compared to the low fatigability group throughout the day (8:00 am to 8:00 pm) and the intermediate fatigability group in the morning (8:00 am to 12:00 pm). Patterns of PA within the high fatigability group differed from both the intermediate and low groups in the morning but mirrored the intermediate group in the afternoon and evening.

Discussion

These results suggest that RPE is a bio-marker of fatigability associated with progressively lower PA with aging. Whether the effects of fatigability occurring at the end of the day reflect waning energy levels or a voluntary choice that could be modified remains to be evaluated.

Fatigability and functional performance among older adults with low-normal ankle-brachial index: Cross-sectional findings from the Baltimore Longitudinal Study of Aging

BACKGROUND AND AIMS

Peripheral artery disease (PAD) is associated with poor mobility and fatigue, but the relationship between preclinical ankle-brachial index (ABI) and early markers of fatigue and functional decline has not been defined.

METHODS

570 adults, 50 and older, from the Baltimore Longitudinal Study of Aging (N = 570), with normal values of ABI (1-1.39), were classified into ABI tertiles. Perceived fatigability was assessed after a 5-min, treadmill walk (1.5 mph) using the Borg rating of perceived exertion (RPE, range 6-20). Functional evaluation included the Health, Aging and Body Composition Physical Performance Battery (HABC PPB), time to complete a 400-m corridor walk (LDCW), and VO₂ peak (ml/kg/min). High RPE and poor walking endurance (PWE) were defined as RPE≥10 and taking >5 min for the LDCW, respectively. Differences between tertiles in fatigability and functional measures were tested adjusting for demographics, behavioral characteristics, self-reported fatigue, and medical history.

RESULTS

Mean LDCW time and RPE were greater for participants in the lowest tertile compared to those in the highest; mean VO₂ peak and HABC PPB scores were lower, suggesting hierarchical associations between fatigability, functional performance, and ABI (p < 0.05 for all). Odds of PWE were greater for those in the lowest ABI tertile compared to the highest; odds of reporting high RPE were greater for those in the middle tertile.

CONCLUSIONS

Lower ABI is associated with poorer physical function and increased fatigability, suggesting that early changes in ABI may infer greater risk of functional decline, even among those who may not progress to PAD.

Hip abductor strength and fatigue are associated with activity levels more than 1 year after total hip replacement

Despite improvements in pain and function, people who undergo total hip arthroplasty (THR) may not always return to desired levels of physical activity (PA). The factors associated with low activity levels are not fully understood. Abductor weakness and fatigue have both been proposed as factors that limit activity in older adults or people with hip osteoarthritis, but have not been investigated after THR. We hypothesized that abductor weakness and fatigue are associated with lower activity levels in people who have undergone a THR and that fatigue mediates the association between abductor strength and activity. We evaluated 16 subjects (24 ± 10 months post-THR; age 56.8 ± 8.4 yrs; BMI 31 ± 7 kg/m² ). Fatigue was assessed using the PROMIS fatigue short-form 7a. Peak isometric hip abductor torque was assessed using a dynamometer with subjects in a sidelying position. We assessed activity level using the UCLA activity score. We used Pearson correlations to explore the associations among the variables. Next we used a three-step linear regression procedure to test whether or not fatigue acted as a mediator between abductor torque and UCLA activity scores. Higher abductor torque was associated with less fatigue (R²  = 0.275; p = 0.037) and with higher UCLA scores (R²  = 0.488, p = 0.003). Higher fatigue was associated with lower UCLA scores (R²  = 0. 307, p = 0.017), however there was no evidence of mediation. This suggests that addressing both abductor strength and fatigue may increase physical activity. Statement of Clinical Significance: Fatigue and abductor weakness should be evaluated in sedentary THR patients presenting for long-term follow-up. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1519-1525, 2018.

Physical Limitations, Walkability, Perceived Environmental Facilitators and Physical Activity of Older Adults in Finland

The aim was to study objectively assessed walkability of the environment and participant perceived environmental facilitators for outdoor mobility as predictors of physical activity in older adults with and without physical limitations. 75–90-year-old adults living independently in Central Finland were interviewed (n = 839) and reassessed for self-reported physical activity one or two years later (n = 787). Lower-extremity physical limitations were defined as Short Physical Performance Battery score ≤9. Number of perceived environmental facilitators was calculated from a 16-item checklist. Walkability index (land use mix, street connectivity, population density) of the home environment was calculated from geographic information and categorized into tertiles. Accelerometer-based step counts were registered for one week (n = 174). Better walkability was associated with higher numbers of perceived environmental facilitators (p < 0.001) and higher physical activity (self-reported p = 0.021, step count p = 0.010). Especially among those with physical limitations, reporting more environmental facilitators was associated with higher odds for reporting at least moderate physical activity (p < 0.001), but not step counts. Perceived environmental facilitators only predicted self-reported physical activity at follow-up. To conclude, high walkability of the living environment provides opportunities for physical activity in old age, but among those with physical limitations especially, awareness of environmental facilitators may be needed to promote physical activity.

Validity of a single question to assess habitual physical activity of community-dwelling older people

The aim is to determine concurrent validity of a single self-report habitual physical activity (PA) question against accelerometer-based PA and mobility variables, and corresponding changes in self-reported PA and mobility. Cross-sectional and longitudinal data of the "Life-space mobility in old age" (LISPE) cohort and its substudy on PA were utilized. At baseline, 848 community-dwelling, 75- to 90-year-old people living independently in central Finland participated in home-based interviews. One and 2 years later, 816 and 761 of them were reassessed by phone, respectively. Tri-axial accelerometer data over 7 days were collected following the baseline assessments in a subsample of 174. Self-reported habitual PA was assessed based on intensity and duration using a single question with seven response options (range: mostly resting to competitive sports). Mobility variables were as follows: life-space mobility, walking difficulty over 500 m, and short physical performance battery. Statistically significant correlations were found between self-reported habitual PA and mobility (Spearman correlation coefficient Rs = 0.40-0.61) and accelerometer-based PA variables [step counts (Rs = 0.49), time in moderate (Rs = 0.49) and low intensity (Rs = 0.40) PA, and time in sedentary behavior (Rs = -0.28)]. A decline in self-reported habitual PA over time was associated with 5-10p decline in life-space mobility (PA improvement with 0-3p increase) and with developing a higher degree of walking difficulty (in 35-44% of participants). In conclusion, based on these results, the self-report question to assess habitual PA is valid and responsive to change and thus useful for epidemiological research in community-dwelling older people, also in follow-up studies.

Effects of blueberry supplementation on measures of functional mobility in older adults

Limited functional mobility in older adults has been associated with declines in tests of motor, psychomotor, and executive function. Animal studies have demonstrated reversals in indices of motor and psychomotor function via supplementation with polyphenolic-rich foods such as blueberries. The purpose of this study was to examine whether 6 weeks of daily consumption of 2 cups of frozen blueberries affects functional mobility in older adults. Pre- and post-intervention assessments of grip strength, simple reaction time, adaptive gait, and executive function were completed for older adults (age >60 years) partially randomly assigned to a blueberry (BB) supplementation or a carrot juice drink control (CAR) group. Paired t tests were used to assess within-group effects for outcome variables in each supplementation group, and a mixed-model analysis of covariance (ANCOVA) was used to determine group (CAR vs. BB) differences. Mixed-model analysis indicated that the BB group demonstrated significant improvements relative to the CAR group in performance (i.e., number of step errors) of a challenging dual-task adaptive gait test that were independent of differences in gait speed. Within only the BB group, significant improvements were also seen in 3 other measures (i.e., usual gait speed; number of step errors during single-task adaptive gait; and gait speed during dual-task adaptive gait). These preliminary findings support the hypothesis that blueberry supplementation may provide an effective countermeasure to age-related declines in functional mobility and serve as justification for an expansion to larger trials to more fully assess this nonpharmacologic approach to maintaining optimal mobility and independence.