Long-Term Effects of a 6-Week Power-Based Resistance Training and Fast Walking Interval Training Program on Physical Function, Muscle Power, Disability, and Frailty in Pre-Frail and Frail Older Adults.

INTRODUCTION: Concurrent training has been shown to be a beneficial approach to improve overall health status in older adults. However, little is known about the adaptations of this type of training in the long term (i.e., after cessation of exercise), even less in older people affected by frailty syndrome. Therefore, this study aimed (i) to assess the effects of a 6-week concurrent training program composed of power-oriented resistance training and fast walking interval training on physical function, muscle power, disability in activities of daily living and frailty in pre-frail and frail older people, and (ii) to assess the effects of a 6-month detraining period on these outcomes. METHODS: A total of 59 pre-frail and frail older adults (>75 years old; Frailty Phenotype >1) were allocated into intervention (INT; n = 32; 81.8 years; 21 women) or control (CON; n = 27; 82.5 years; 19 women) groups. Primary outcomes of this study were Short Physical Performance Battery (SPPB), relative sit-to-stand (STS) power, Barthel index, Lawton scale and Frailty Phenotype. Assessments were performed at baseline (PRE), after the concurrent training programme (POST) and after 6 months of follow-up (DET) in both groups. Mixed model repeated measures ANOVA with Bonferroni's post hoc tests was used. RESULTS: Immediately after the intervention (∆ = POST-PRE), INT improved SPPB (∆ = 3.0 points; p < 0.001), relative STS power (∆ = 0.87 W·kg-1; p < 0.001) and reduced their frailty levels (∆ = -1.42 criteria; p < 0.001), while no changes were observed in CON. After 6 months of detraining (∆ = DET-PRE), INT showed higher SPPB (∆ = 2.2 points; p < 0.001), higher relative STS power (∆ = 0.73 W·kg-1; p < 0.001) and lower frailty (∆ = -1.24 criteria; p < 0.001) values than those reported at baseline, which were significantly different than those reported by CON. Both, Barthel index and Lawton scale values were not modified during the study in either group. CONCLUSIONS: The 6-week concurrent training program improved physical function, muscle power and reduced frailty in pre-frail and frail older people and these improvements were maintained above baseline levels after 6 months of detraining. However, due to the individual variability found, future studies of long-term responders versus non-responders in frail populations are required.

Power-oriented resistance training combined with high-intensity interval training in pre-frail and frail older people: comparison between traditional and cluster training set configurations on the force-velocity relationship, physical function and frailty.

OBJECTIVES: To analyse the force-velocity relationship changes in response to two different training programmes differing in the set configuration (cluster vs. traditional), and their impact on physical function and frailty in pre-frail and frail older adults. METHODS: 43 pre-frail and frail (Frailty Phenotype ≥ 1 criteria) older adults (81.4 ± 5.1 years) participated in this study. Participants were assigned to cluster (CT; n = 10; 10-s intra-set rest), traditional (TT; n = 13; no intra-set rest) or control (CON; n = 20) groups. Force-velocity relationship (F0, V0 and Pmax), physical function (Short Physical Performance Battery, SPPB) and frailty (Frailty Phenotype, FP) were assessed at baseline and after the training programme. RESULTS: Both CT and TT groups showed similar improvements in Pmax after training (CT = + 36.7 ± 34.2 W; TT = + 33.8 ± 44.6 W; both p < 0.01). V0 was improved by both CT (+ 0.08 ± 0.06 m s-1; p < 0.01), and TT (+ 0.07 ± 0.15 m s-1, p > 0.05). F0 remained unchanged in CT (+ 68.6 ± 224.2 N, p > 0.05) but increased in TT (+ 125.4 ± 226.8 N, p < 0.05). Finally, SPPB improved in both training conditions (CT = + 2.3 ± 1.3 points; TT = + 3.0 ± 1.2 points; both p < 0.05) and in the CON group (+ 0.9 ± 1.4 points, p < 0.05). CT and TT reduced their FP (CT = - 1.1 criteria; TT = - 1.6 criteria; both p < 0.01), while no changes were observed in the CON group (- 0.2 criteria, p = 0.38). CONCLUSIONS: Both training methods were equally effective for improving Pmax, physical function and reducing frailty in pre-frail and frail older people. TT may be effective for improving both force and velocity parameters, while CT may be effective for improving velocity parameters alone, although further research is required to confirm these findings.

Optimization of VO2 and VCO2 outputs for the calculation of resting metabolic rate using a portable indirect calorimeter.

This study aimed to compare the Cosmed K5 portable indirect calorimeter, using the mixing chamber mode and face mask, with a stationary metabolic cart when measuring the resting metabolic rate (RMR) and to derive fitting equations if discrepancies are observed. Forty-three adults (18-84 years) were assessed for their RMR for two 30-min consecutive and counterbalanced periods using a Cosmed K5 and an Oxycon Pro. Differences among devices were tested using paired sample Student's t-tests, and correlation and agreement were assessed using Pearson's correlation coefficients, intraclass correlation coefficient and Bland-Altman plots. Forward stepwise multiple linear regression models were performed to develop fitting equations for estimating differences among devices when assessing oxygen uptake (VO2 diff , mL·min-1 ) and carbon dioxide production (VCO2 diff , mL·min-1 ). Furthermore, the Oxycon Pro was tested before being confirmed as a reference device. Significant differences between devices were found in most metabolic and ventilatory parameters, including the primary outcomes of VO2 and VCO2 . These differences showed an overestimation of the Cosmed K5 in all metabolic outcomes, except for Fat, when compared to the Oxycon Pro. When derived fitting equations were applied (VO2 diff - 139.210 + 0.786 [weight, kg] + 1.761 [height, cm] - 0.941 [Cosmed K5 VO2 , mL·min-1 ]; VCO2 diff - 86.569 + 0.548 [weight, kg] + 0.915 [height, cm] - 0.728 [Cosmed K5 VCO2 , mL·min-1 ]), differences were minimized, and agreement was maximized. This study provides fitting equations which allow the use of the Cosmed K5 for reasonably optimal RMR determinations.

Residual effects of 12 weeks of power-oriented resistance training plus high-intensity interval training on muscle dysfunction, systemic oxidative damage, and antioxidant capacity after 10 months of training cessation in older people with COPD.

OBJECTIVE: This study aimed to assess the residual effects of a 12-week concurrent training program (power training + high-intensity interval training) in older adults with chronic obstructive pulmonary disease (COPD). METHODS: A total of 21 older adults with COPD [intervention (INT), n = 8; control (CON), n = 13; 76.9 ± 6.8 years] were assessed at baseline and 10 months after the completion of the intervention by the short physical performance battery (SPPB), health-related quality of life (EQ-5D-5L), vastus lateralis muscle thickness (MT), peak pulmonary oxygen uptake (peak VO2 ) and peak work rate (Wpeak ), early and late isometric rate of force development (RFD), leg and chest press maximum muscle power (LPmax and CPmax ), and systemic oxidative damage and antioxidant capacity. RESULTS: Compared to baseline, after 10 months of detraining, the INT group presented increased SPPB (∆ = 1.0 point), health-related quality of life (∆ = 0.07 points), early RFD (∆ = 834 N∙s-1 ), LPmax (∆ = 62.2 W), and CPmax (∆ = 16.0 W) (all p < 0.05). In addition, a positive effect was noted in INT compared to CON regarding MT and Wpeak (both p < 0.05). No between-group differences were reported in peak VO2 , late RFD, systemic oxidative damage, and antioxidant capacity from baseline to 10 months after the completion of the intervention (all p > 0.05). CONCLUSIONS: Twelve weeks of concurrent training were enough to ensure improved physical function, health-related quality of life, early RFD and maximum muscle power and to preserve MT and Wpeak but not peak VO2 , late RFD, systemic oxidative damage and antioxidant capacity in the subsequent 10 months of detraining in older adults with COPD.

Effects of concurrent exercise training on muscle dysfunction and systemic oxidative stress in older people with COPD.

Oxidative stress is associated with disease severity and limb muscle dysfunction in COPD. Our main goal was to assess the effects of exercise training on systemic oxidative stress and limb muscle dysfunction in older people with COPD. Twenty-nine outpatients with COPD (66-90 years) were randomly assigned to a 12-week exercise training (ET; high-intensity interval training (HIIT) plus power training) or a control (CT; usual care) group. We evaluated mid-thigh muscle cross-sectional area (CSA; computed tomography); vastus lateralis (VL) muscle thickness, pennation angle, and fascicle length (ultrasonography); peak VO2 uptake (VO2peak ) and work rate (Wpeak ) (incremental cardiopulmonary exercise test); rate of force development (RFD); maximal muscle power (Pmax ; force-velocity testing); systemic oxidative stress (plasma protein carbonylation); and physical performance and quality of life. ET subjects experienced changes in mid-thigh muscle CSA (+4%), VL muscle thickness (+11%) and pennation angle (+19%), VO2peak (+14%), Wpeak (+37%), RFD (+32% to 65%), Pmax (+38% to 51%), sit-to-stand time (-24%), and self-reported health status (+20%) (all P < 0.05). No changes were noted in the CT group (P > 0.05). Protein carbonylation decreased among ET subjects (-27%; P < 0.05), but not in the CT group (P > 0.05). Changes in protein carbonylation were associated with changes in muscle size and pennation angle (r = -0.44 to -0.57), exercise capacity (r = -0.46), muscle strength (r = -0.45), and sit-to-stand performance (r = 0.60) (all P < 0.05). The combination of HIIT and power training improved systemic oxidative stress and limb muscle dysfunction in older people with COPD. Changes in oxidative stress were associated with exercise-induced structural and functional adaptations.

The Force-Velocity Relationship in Older People: Reliability and Validity of a Systematic Procedure.

This study compared the reliability and validity of different protocols evaluating the force-velocity (F-V) relationship and muscle power in older adults. Thirty-one older men and women (75.8±4.7 years) underwent two F-V tests by collecting the mean and peak force and velocity data exerted against increasing loads until one repetition maximum (1RM) was achieved in the leg press exercise. Two attempts per load were performed, with a third attempt when F-V points deviated from the linear F-V regression equation. Then, the subjects performed 2×3 repetitions at 60% 1RM to compare purely concentric and eccentric-concentric repetitions. The Short Physical Performance Battery was conducted to assess the validity of the different protocols. Significant differences were found in maximal power (Pmax) between mean and peak values and between protocols differing in the number of attempts per load (p<0.01). Registering mean values, a third attempt, and multiple loads (>3), was significantly more reliable (Pmax: CV=2.6%; ICC=0.99) than the other alternatives. Mean values were also observed to be more associated with physical function than peak values (R2=0.34 and 0.15, respectively; p<0.05). No significant differences were observed between concentric and eccentric-concentric repetitions. Thus, collecting mean force and velocity values against multiple loads, while monitoring the linearity of the F-V relationship, seemed to be the more adequate procedure to assess the F-V profile and muscle power in older adults.

Impact of Relative Muscle Power on Hospitalization and All-Cause Mortality in Older Adults.

BACKGROUND: The purpose of this study was to evaluate the relationship of lower-limb muscle power with mortality and hospitalization. METHODS: A total of 1 928 participants from the Toledo Study for Healthy Aging were included. Muscle power was assessed with the 5-repetition sit-to-stand test and participants were classified into different groups of relative power (ie, normalized to body mass) according to sex-specific tertiles and their inability to perform the test. Mean follow-up periods for hospitalization and all-cause mortality were 3.3 and 6.3 years, respectively. RESULTS: Compared to the high relative muscle power group, men with low (HR [95% CI] = 2.1 [1.2-3.6]) and women with very low and low (HR [95% CI] = 4.7 [3.0-7.4] and 1.8 [1.2-2.7]) relative power had an increased age-adjusted risk of hospitalization. After adjusting for several covariates (age, physical activity, body mass index education, depression, comorbidities, disability, and handgrip strength), these effects were attenuated (men and women with very low relative power: HR [95% CI] = 1.6 [0.9-2.9] and 2.8 [1.6-4.9]). The very low relative muscle power group had also an increased all-cause mortality risk (age-adjusted) in both men and women (HR [95% CI] = 2.3 [1.4-3.9] and 2.9 [1.6-5.3]). After adjusting for all the covariates, a significantly increased mortality risk was observed only in men (HR [95% CI] = 2.1 [1.1-3.8]; women HR [95% CI] = 1.6 [0.8-3.2]), with very low levels of relative power. CONCLUSIONS: Relative muscle power was independently and negatively associated with mortality and hospitalization in older adults. An augmented all-cause mortality risk was noted in the lowest group of relative muscle power.

Relative sit-to-stand power cut-off points and their association with negatives outcomes in older adults.

The purposes of this study were: (i) to evaluate the association of sit-to-stand (STS) power and body composition parameters [body mass index (BMI) and legs skeletal muscle index (SMI)] with age; (ii) to provide cut-off points for low relative STS power (STSrel), (iii) to provide normative data for well-functioning older adults and (iv) to assess the association of low STSrel with negative outcomes. Cross-sectional design (1369 older adults). STS power parameters assessed by validated equations, BMI and Legs SMI assessed by dual-energy X-ray absorptiometry were recorded. Sex- and age-adjusted segmented and logistic regression analyses and receiver operator characteristic curves were used. Among men, STSrel showed a negative association with age up to the age of 85 years (- 1.2 to - 1.4%year-1; p < 0.05). In women, a negative association with age was observed throughout the old adult life (- 1.2 to - 2.0%year-1; p < 0.001). Cut-off values for low STSrel were 2.5 W kg-1 in men and 1.9 W kg-1 in women. Low STSrel was associated with frailty (OR [95% CI] = 5.6 [3.1, 10.1]) and low habitual gait speed (HGS) (OR [95% CI] = 2.7 [1.8, 3.9]) in men while low STSrel was associated with frailty (OR [95% CI] = 6.9 [4.5, 10.5]) low HGS (OR [95% CI] = 2.9 [2.0, 4.1]), disability in activities of daily living (OR [95% CI] = 2.1 [1.4, 3.2]), and low quality of life (OR [95%CI] = 1.7 [1.2, 2.4]) in women. STSrel declined with increasing age in both men and women. Due to the adverse outcomes related to STSrel, the reported cut-off points can be used as a clinical tool to identify low STSrel among older adults.

Low relative mechanical power in older adults: An operational definition and algorithm for its application in the clinical setting.

INTRODUCTION: The assessment and treatment of low relative muscle power in older people has received little attention in the clinical setting when compared to sarcopenia. Our main goal was to assess the associations of low relative power and sarcopenia with other negative outcomes in older people. METHODS: The participants were 1189 subjects (54% women; 65-101 years old) from the Toledo Study for Healthy Aging. Probable sarcopenia was defined as having low handgrip strength, while confirmed sarcopenia also included low appendicular skeletal muscle index (assessed by dual energy X-ray absorptiometry) (EWGSOP2's definition). Low relative (i.e. normalized to body mass) muscle power was assessed with the 5-repetition sit-to-stand power test (which uses an equation that converts sit-to-stand performance into mechanical power) and diagnosed in those subjects in the lowest sex-specific tertile. Low usual gait speed (UGS), frailty (according to Fried's criteria and the Frailty Trait Scale), limitations in basic (BADL) and instrumental activities of daily living (IADL) and poor quality of life were also recorded. RESULTS: Age-adjusted logistic regression analyses demonstrated that low relative muscle power was associated with low UGS (odds ratio (OR) = 1.9 and 2.5), frailty (OR = 3.9 and 4.7) and poor quality of life (OR = 1.8 and 1.9) in older men and women, respectively, and with limitations in BADL (OR = 1.6) and IADL (OR = 3.8) in older women (all p < 0.05). Confirmed sarcopenia was only associated with low UGS (OR = 2.5) and frailty (OR = 5.0) in older men, and with limitations in IADL in older women (OR = 4.3) (all p < 0.05). CONCLUSIONS: Low relative muscle power had a greater clinical relevance than low handgrip strength and confirmed sarcopenia among older people. An operational definition and algorithm for low relative muscle power case finding in daily clinical practice was presented.

Frailty Trait Scale-Short Form: A Frailty Instrument for Clinical Practice.

OBJECTIVES: To develop short versions of the Frailty Trait Scale (FTS) for use in clinical settings. DESIGN: Prospective population-based cohort study. SETTING AND PARTICIPANTS: Data from 1634 participants from the Toledo Study for Healthy Aging. METHODS: The 12-item Frailty Trait Scale (FTS) reduction was performed based on an area under the curve (AUC) analysis adjusted by age, sex, and comorbidity. Items that maximized prognostic information for adverse events were selected. Each item score was done at the same time as the reduction, identifying the score that maximized the predictive ability for adverse events. For each short version of the FTS, cutoffs that optimized the prognostic information (sensitivity and specificity) were chosen, and their predictive value was later compared with a surrogate gold standard for frailty (the Fried Phenotype). RESULTS: Two short forms, the 5-item (FTS5) (range 0-50) and 3-item (FTS3) (range 0-30), were identified, both with AUCs for health adverse events similar to the 12-item FTS. The identified cutoffs were >25 for the FTS5 scale and >15 for the FTS3. The frailty prevalence with these cutoffs was 24% and 20% for the FTS5 and FTS3, respectively, whereas frailty according to Fried Phenotype (FP) reached 8% and prefrailty reached 41%. In general, the FTS5 showed better prognostic performance than the FP, especially with prefrail individuals, in whom the FTS5 form identified 65% of participants with an almost basal risk and 35% with a very high risk for mortality (OR: 4) and frailty (OR: 6.6-8.7), a high risk for hospitalization (OR: 1.9-2.1), and a moderate risk for disability (OR: 1.7) who could be considered frail. The FTS3 form had worse performance than the FTS5, showing 31% of false negatives between frail participants identified by FP with a high risk of adverse events. CONCLUSIONS AND IMPLICATIONS: The FTS5 is a short scale that is easy to administer and has a similar performance to the FTS, and it can be used in clinical settings for frailty diagnosis and evolution.

The Effect of the Stretch-Shortening Cycle in the Force-Velocity Relationship and Its Association With Physical Function in Older Adults With COPD.

This study aimed to evaluate the effect of the stretch-shortening cycle (SSC) on different portions of the force-velocity (F-V) relationship in older adults with and without chronic obstructive pulmonary disease (COPD), and to assess its association with physical function. The participants were 26 older adults with COPD (79 ± 7 years old; FEV1 = 53 ± 36% of predicted) and 10 physically active non-COPD (77 ± 4 years old) older adults. The F-V relationship was evaluated in the leg press exercise during a purely concentric muscle action and compared with that following an eccentric muscle action at 10% intervals of maximal unloaded shortening velocity (V0). Vastus lateralis (VL) muscle thickness, pennation angle (PA), and fascicle length (FL) were assessed by ultrasound. Habitual gait speed was measured over a 4-m distance. COPD subjects exhibited lower physical function and concentric maximal muscle power (Pmax) values compared with the non-COPD group (both p < 0.05). The SSC increased force and power values among COPD participants at 0-100 and 1-100% of V0, respectively, while the same was observed among non-COPD participants only at 40-90 and 30-90% of V0, respectively (all p < 0.05). The SSC induced greater improvements in force, but not power, among COPD compared with non-COPD subjects between 50 and 70% of V0 (all p < 0.05). Thus, between-group differences in muscle power were not statistically significant after the inclusion of the SSC (p > 0.05). The SSC-induced potentiation at 50-100% of V0 was negatively associated with physical function (r = -0.40-0.50), while that observed at 80-100% of V0 was negatively associated with VL muscle thickness and PA (r = -0.43-0.52) (all p < 0.05). In conclusion, older adults with COPD showed a higher SSC-induced potentiation compared with non-COPD subjects, which eliminated between-group differences in muscle power when performing SSC muscle actions. The SSC-induced potentiation was associated with lower physical function, VL muscle thickness, and VL PA values. The SSC-induced potentiation may help as a compensatory mechanism in those older subjects with a decreased ability to produce force/power during purely concentric muscle actions.

Effect of a short multicomponent exercise intervention focused on muscle power in frail and pre frail elderly: A pilot trial.

OBJECTIVES: The aim was to establish whether a short supervised facility-based exercise program improved frailty, physical function and performance in comparison with usual care treatment. METHODS: This was a quasi-experimental, non-randomized controlled intervention study in frail (2.75 ±â€¯1.25 Frailty Phenotype criteria) older adults (range:77.2-95.8 years). The exercise (EX) group (n = 11) performed concurrent training (power training + high-intensity interval training, HIIT) twice weekly for 6 weeks while the control (CT) group (n = 9) followed usual care. RESULTS: The exercise intervention improved frailty status in 64% of the subjects improving Frailty Phenotype by 1.6 points (95%CI 0.8-2.5, p < 0.05), and increasing SPPB score by 3.2 points (95%CI: 2.4-4.0, Cohen's d = 2.0, p < 0.05), muscle power by 47% (95%CI: 7-87%, Cohen's d = 0.5, p < 0.05), muscle strength by 34%(95%CI: 7-60, Cohen's d = 0.6, p < 0.05) and the aerobic capacity by 19% (6 minute walking test +45 m, 95%CI: 7-83, Cohen's d = 0.7, p = 0.054). The CT did not experience any significant changes in frailty status, physical function or performance. CONCLUSIONS: A short concurrent exercise program of muscle power and walking-based HIIT training is a feasible and safe method to increase physical performance and improve function and frailty in elder (pre)frail patients.

The sit-to-stand muscle power test: An easy, inexpensive and portable procedure to assess muscle power in older people.

INTRODUCTION: Skeletal muscle power has been demonstrated to be a stronger predictor of functional limitations than any other physical capability. However, no validated alternatives exist to the usually expensive instruments and/or time-consuming methods to evaluate muscle power in older populations. Our aim was to validate an easily applicable procedure to assess muscle power in large cohort studies and the clinical setting and to assess its association with other age-related outcomes. METHODS: Forty community dwelling older adults (70-87 years) and 1804 older subjects (67-101 years) participating in the Toledo Study for Healthy Aging were included in this investigation. Sit-to-stand (STS) velocity and muscle power were calculated using the subject's body mass and height, chair height and the time needed to complete five STS repetitions, and compared with those obtained in the leg press exercise using a linear position transducer. In addition, STS performance, physical (gait speed) and cognitive function, sarcopenia (skeletal muscle index (SMI)) and health-related quality of life (HRQoL) were recorded to assess the association with the STS muscle power values. RESULTS: No significant differences were found between STS velocity and power values and those obtained from the leg press force-velocity measurements (mean difference ±â€¯95% CI = 0.02 ±â€¯0.05 m·s-1 and 6.9 ±â€¯29.8 W, respectively) (both p > 0.05). STS muscle power was strongly associated with maximal muscle power registered in the leg press exercise (r = 0.72; p < 0.001). In addition, cognitive function and SMI, and physical function, were better associated with absolute and relative STS muscle power, respectively, than STS time values after adjusting by different covariates. In contrast, STS time was slightly more associated with HRQoL than STS muscle power measures. CONCLUSION: The STS muscle power test proved to be a valid, and in general, a more clinically relevant tool to assess functional trajectory in older people compared to traditional STS time values. The low time, space and material requirements of the STS muscle power test, make this test an excellent choice for its application in large cohort studies and the clinical setting.

Force-velocity profiling in older adults: An adequate tool for the management of functional trajectories with aging.

INTRODUCTION: The actual mechanisms leading to a reduced muscle power and functional ability in older adults are poorly understood. We investigated the association between different force-velocity (F-V) profiles and impaired muscle power, physical and cognitive function, frailty, and health-related quality of life (HRQoL) in older people. METHODS: Physical function (habitual gait speed, timed up-and-go test, sit-to-stand and stair-climbing ability), cognitive function, HRQoL and frailty were evaluated in 31 older subjects (70-85 years). The F-V relationship and maximal muscle power (Pmax) were assessed in the leg press exercise. The skeletal muscle index (SMI) and fat index, moderate-to-vigorous physical activity (MVPA) and sedentary time were obtained from DXA scans and accelerometry, respectively. RESULTS: While some subjects showed a force deficit (FDEF), others presented a velocity deficit (VDEF), both leading to an impaired muscle power [Effect size (ES) = 1.30-1.44], and to a likely-very likely moderate harmful effect in their physical and cognitive function, HRQoL and frailty levels (except the VDEF group for cognitive function) [ES = 0.76-1.05]. Leg muscle mass and specific force were similarly associated with force at Pmax, while MVPA but not sedentary time was related to fat index, force at Pmax, and power values (all p < 0.05). A trend was found for the negative association between fat index and relative Pmax (p = 0.075). CONCLUSION: Older subjects exhibited different mechanisms (force vs. velocity deficits) leading to impaired muscle power. Both deficits were associated with a lower physical function and quality of life, and a higher frailty, whereas only a force deficit was associated with a lower cognitive function. Interventions aimed at reversing age- and/or disuse-related impairments of muscle power might evaluate the specific responsible mechanism and act accordingly.

Reallocating Accelerometer-Assessed Sedentary Time to Light or Moderate- to Vigorous-Intensity Physical Activity Reduces Frailty Levels in Older Adults: An Isotemporal Substitution Approach in the TSHA Study.

INTRODUCTION: The effects of replacing sedentary time with light or moderate- to vigorous-intensity physical activity on frailty are not well known. AIM: To examine the mutually independent associations of sedentary time (ST), light-intensity physical activity (LPA), and moderate- to vigorous-intensity physical activity (MVPA) with frailty status in older adults. METHODS: A total of 628 people aged ≥65 years from the Toledo Study of Healthy Aging (TSHA) participated in this cross-sectional study. Frailty was measured using the Frailty Trait Scale. Hip-worn accelerometers were used to capture objective measurements of ST, LPA, and MVPA. Linear regression and isotemporal substitution analyses were used to examine associations of ST, LPA, and MVPA with frailty status. Analyses were also stratified by comorbidity. RESULTS: In single and partition models, LPA and MVPA were negatively associated with frailty. Time in sedentary behavior was not associated with frailty in these models. In the isotemporal substitution models, replacing 30 minutes/d of ST with MVPA was associated with a decrease in frailty [ß -2.460; 95% confidence interval (CI): -3.782, -1.139]. In contrast, replacing ST with LPA was not associated with favorable effects on this outcome. However, when the models were stratified by comorbidity, replacing ST with MVPA had the greatest effect on frailty in both the comorbidity (ß -2.556; 95% CI: -4.451, -0.661) and the no comorbidity group (ß -2.535; 95% CI: -4.343, -0.726). Moreover, the favorable effects of LPA in people with comorbidities was found when replacing 30 minutes/d of ST with LPA (ß -0.568; 95% CI: -1.050, -0.086). CONCLUSIONS: Substituting ST with MVPA is associated with theoretical positive effects on frailty. People with comorbidity may also benefit from replacing ST with LPA, which may have important clinical implications in order to decrease the levels of physical frailty.

Does 8-foot walk time predict cognitive decline in older Mexicans Americans?

OBJECTIVES: To examine the association between 8-foot time walk and change in cognitive function over time in older Mexican Americans. DESIGN: Data used are from the Hispanic Established Population for the Epidemiological Study of the Elderly (1993-2001). SETTING: Five southwestern states: Texas, New Mexico, Colorado, Arizona, and California. PARTICIPANTS: Two thousand seventy noninstitutionalized Mexican-American men and women aged 65 and older who had a Mini-Mental State Examination (MMSE) score of 21 or greater at baseline. MEASUREMENTS: Sociodemographic factors (age, sex, education, marital status), MMSE score, 8-foot walk time, body mass index, medical conditions (stroke, heart attack, diabetes mellitus, depression, and hypertension), and near and distant visual impairment. RESULTS: Using general linear mixed models, it was found that subjects with the slowest 8-foot walk time had a significantly greater rate of cognitive decline over 7 years than subjects with the fastest 8-foot walk time. There was a significant 8-foot walk time-by-time interaction with MMSE scores. Subjects in the lowest 8-foot walk time quartile had a greater cognitive decline over 7 years (estimate=-0.32, SE=0.08; P<.001) than those in the highest quartile. This association remained statistically significant after controlling for potential confounding factors. CONCLUSION: Slow 8-foot walk time in older Mexican-American adults without cognitive impairment at baseline was an independent predictor of MMSE score decline over a 7-year period. Slow 8-foot walk time may be an early marker for older adults in a predementia state who may benefit from early-intervention programs to prevent or slow cognitive decline.

Cognitive Performance across 3 Frailty Phenotypes: Toledo Study for Healthy Aging.

INTRODUCTION: Frailty is a strong predictor of adverse health events, but its impact on cognitive function is poorly understood. AIM: To assess cognitive performance in frailty and to identify the frailty stage where cognitive impairment begins. METHODS: Data were taken from 2044 people aged ≥65 years without cognitive impairment selected from the Toledo Study for Healthy Aging, a population-based cohort of older adults. Frailty status was assessed by 3 different scales: Frailty Phenotype (FP), Frailty Trait Scale (FTS), and Frailty Index (FI). Neuropsychological assessments of different cognitive domains included the Mini-Mental State Examination, Short and Long-Term Memory Recalling Test, the Boston Naming Test, Verbal Fluency Test, Digit Span Forward, Go/No-go Test, Luria Orders Test, Clock Drawing Test, and Serial Word Learning Test. The relationships between the score of the scales and frailty status (robust, prefrail, and frail for FP and quartiles for FTS and FI) were analyzed using multivariate linear regression models including age, sex, and educative level as possible confounders. RESULTS: Participants classified as the worst degree of frailty (frail in FP and fourth quartile of FTS and FI) presented more cognitive domains affected and to a higher extent than moderate frail (prefrail and second quartile and third quartile of FTS and FI) and robust (and first quartile of FTS and FI) participants. CONCLUSIONS: Cognitive performance progressively declined across the frailty state, regardless of the instrument used to assess frailty. In prefrail participants, cognitive impairment may be an early marker of frailty-dependent cerebral involvement and could be already subject to interventions aimed at reducing the transition to frailty.

Endocrinology of Aging From a Muscle Function Point of View: Results From the Toledo Study for Healthy Aging.

INTRODUCTION: Aging is a process that involves a reduction in muscle strength and anabolic hormone concentrations, which impacts significantly on health. AIM: To study the hormone/total strength (H/TS) ratio as a proxy of anabolic insensitivity status in elders, and its relationship with disability, hospitalization, and mortality risk. DESIGN: A total of 1462 persons aged ≥65 years from the Toledo Study of Healthy Aging participated in this study. Serum concentrations of insulin like growth factor 1, total and free testosterone, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and 17ß-estradiol were measured. Total maximal voluntary isometric strength was obtained (handgrip, shoulder, hip, and knee) using standardized techniques and equipment. Physical activity was recorded by physical activity scale for the elderly questionnaire. Associations of the H/TS ratio with hospitalization and mortality were assessed using logistic regression models, and participants stratified into quartiles for each H/TS ratio. RESULTS: In women, all individual ratio H/TS models showed a strong to moderate increased risk for death and hospitalization. In men, all models revealed a significant positive association of the ratio H/TS with mortality rate but not for hospitalization (P < .01). Participants who have 2 or more H/TS ratios in the worst quartile increased the risk of hospitalization and mortality at least by 2-fold. CONCLUSIONS: We demonstrate the main role that muscle function plays in the relationship between the hormonal status and hospitalization and mortality risk; this could be taken into consideration as a way to classify patients for hormonal therapy.

Cognitive status, body mass index, and hip fracture in older Hispanic adults.

OBJECTIVES: To examine the interactive effect of cognition and body weight on hip fracture. DESIGN: A 7-year (1993-2000) prospective cohort study. SETTING: Five southwestern states (Texas, New Mexico, Arizona, Colorado, and California). PARTICIPANTS: Noninstitutionalized Mexican Americans (N=2,653) aged 65 and older and free of hip fracture at baseline interview. MEASUREMENTS: Incidence of hip fracture at 2-, 5-, and 7-year follow-up interviews. Body weight and cognition were measured using body mass index (BMI) and Mini-Mental State Examination score, respectively. Covariates included sociodemographics, self-reported medical conditions, visual acuity, and Short Physical Performance Battery. RESULTS: A significant interaction between BMI and hip fracture was found in persons with cognitive impairment (hazard ratio =0.91, 95% confidence interval=0.85-0.98; P=.02), after adjusting for covariates. In the lowest BMI category, the hip fracture rate in cognitively impaired subjects was more than four times the hip fracture rate for subjects who were not cognitively impaired with the same BMI (34.6% vs 8.7%). Hip fracture rates in the highest BMI category were similar in persons with and without cognitive impairment (9.3% vs 6.1%). CONCLUSION: Low cognitive function increased the conditional association between BMI and hip fracture in older Mexican Americans. The relationship between BMI and cognition is potentially important in identifying persons at risk for hip fracture and supports the need to include cognitive and anthropometric measures in the assessment of hip fracture risk into osteoporosis screening programs.

Handgrip strength and cognitive decline in older Mexican Americans.

BACKGROUND: Cognitive decline and dementia are associated with disability and premature death in old age. We examined whether low handgrip strength predicts subsequent cognitive decline in older Mexican Americans. METHODS: We worked with a 7-year prospective cohort of 2160 noninstitutionalized Mexican Americans aged 65 years or older from the Hispanic Established Population for the Epidemiological Study of the Elderly (H-EPESE) who had a Mini-Mental State Examination (MMSE) score > or = 21 at baseline. Measures included: (i) sociodemographic factors (age, gender, and education), handgrip strength, and near and distant visual impairment from baseline interview; and (ii) MMSE, body mass index (BMI), and medical conditions (stroke, heart attack, diabetes, depression, and hypertension) from four waves of data collection. RESULTS: Using general linear mixed models, we found a significant trend with scores in the lowest quartile of handgrip strength at baseline to be associated with lower MMSE scores over time (estimate = -1.28, standard error = 0.16; p <.0001). There was a significant handgrip Strength-by-Time interaction with MMSE scores. Participants in the lowest handgrip strength quartile had a greater cognitive decline over time (estimate = -0.26, standard error = 0.07; p <.001) than did those participants in the highest quartile. This association remained statistically significant after controlling for potential confounding factors. CONCLUSION: Older Mexican Americans with reduced handgrip strength at baseline demonstrated a statistically significant decline in cognitive function over a 7-year period. By contrast, participants in the highest handgrip strength quartile maintained a higher level of cognitive function.