Attenuation of cardiovascular adaptations to exercise in frail octogenarians

Development of an Algorithm to Screen for Frailty Using the Clinical Frailty Scale with Postoperative Patients Entering Cardiac Rehabilitation

Purpose

Frailty is not commonly assessed on intake to cardiac rehabilitation (CR), but screening could enable targeted interventions and potentially reduce secondary complications. This study aimed to develop and retrospectively examine the feasibility of utilizing a CR-specific algorithm based on the Clinical Frailty Scale (CFS). Our CFS-CR algorithm endeavoured to screen for frailty in older adults (> 65 y) entering CR following cardiac surgery/procedure.

Method

The charts of 30 former patients (mean age: 74.0 ± 6.9 y) were examined by a clinician working in CR.

Results

The clinician was unable to score any of the patients based on their medical charts using the CFS-CR due to insufficient data. Documentation was typically limited in the areas of instrumental and basic activities of daily living whereas exercise data were readily available.

Conclusions

Current intake documentation in CR limited the ability to retrospectively screen for frailty. This finding suggests a need for a frailty-specific tool to support routine clinical screening. Prospective evaluation of the CFS-CR is warranted to further examine the clinical utility of the algorithm during CR intake assessments.

Effects of aging and endurance exercise training on cardiorespiratory fitness and cardiac structure and function in healthy midlife and older women

Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality in women in developed societies. Unfavorable structural and functional adaptations within the heart and central blood vessels with sedentary aging in women can act as the substrate for the development of debilitating CVD conditions such as heart failure with preserved ejection fraction (HFpEF). The large decline in cardiorespiratory fitness, as indicated by maximal or peak oxygen uptake (V̇o2max and V̇o2peak, respectively), that occurs in women as they age significantly affects their health and chronic disease status, as well as the risk of cardiovascular and all-cause mortality. Midlife and older women who have performed structured endurance exercise training for several years or decades of their adult lives exhibit a V̇o2max and cardiac and vascular structure and function that are on par or even superior to much younger sedentary women. Therefore, regular endurance exercise training appears to be an effective preventative strategy for mitigating the adverse physiological cardiovascular adaptations associated with sedentary aging in women. Herein, we narratively describe the aging and short- and long-term endurance exercise training adaptations in V̇o2max, cardiac structure, and left ventricular systolic and diastolic function at rest and exercise in midlife and older women. The role of circulating estrogens on cardiac structure and function is described for consideration in the timing of exercise interventions to maximize beneficial adaptations. Current research gaps and potential areas for future investigation to advance our understanding in this critical knowledge area are highlighted.

Predictors of Improvement in Exercise Capacity After Cardiac Rehabilitation Differ Between Octogenarian and Young-Old Patients With Acute Myocardial Infarction

BACKGROUND

Whether the magnitude and predictors of improvement in exercise capacity after cardiac rehabilitation (CR) are the same between young-old (YO) and octogenarian (OCT) patients with acute myocardial infarction (AMI) is unknown.Methods and Results: We studied 284 YO (age range 65-69 years; mean [±SD] 67±1 years) and 65 OCT (age range ≥80 years; mean [±SD] 83±2 years) patients who participated in a post-AMI CR program. After 3 months of CR, peak oxygen uptake (PV̇O₂) measured during cardiopulmonary exercise testing improved significantly in both age groups (P<0.01), although the percentage increase in PV̇O₂(%∆PV̇O₂) was significantly smaller in the OCT than YO group (5.4±13.7% vs. 10.0±12.8%; P<0.01). Multiple regression analysis demonstrated that independent predictors of %∆PV̇O₂were the number of outpatient CR (OPCR) sessions attended (P=0.015), left ventricular ejection fraction (P=0.028), and baseline PV̇O₂(P=0.0007) in the YO group; and the number of sessions attended (P=0.018), atrial fibrillation (P=0.042), and the presence of nutritional risk (Geriatric Nutritional Risk Index ≤98; P=0.036) in the OCT group.

CONCLUSIONS

The predictors of improvement in exercise capacity after CR differed between the YO and OCT patients with AMI. To obtain a greater improvement in PV̇O₂in CR, frequent OPCR session attendance may be necessary in both groups; in addition, particularly in OCT patients, better nutritional status may be important.

Hybrid Exercise Program Enhances Physical Fitness and Reverses Frailty in Older Adults: Insights and Predictions from Machine Learning

PURPOSE

The declining physical condition of the older adults is a pressing issue. Wu Qin Xi exercise, despite being low-intensity, is highly effective among older adults. Inspired by its characteristics, we designed a new exercise program for frail older adults, combining strength, endurance, and Wu Qin Xi. Furthermore, we employed machine learning to predict whether frailty can be reversed in older adults after the intervention.

METHODS

A total of 181 community-dwelling frail older adults aged 65 years or older participated in this single-center, randomized controlled study, with 54.7% (n=99) being female. The study assessed the effectiveness of several exercise modalities in reversing frailty. The Fried's frailty criterion was used to assess the degree of frailty of the subjects. Participants were assigned a three-digit code 001-163 and randomly assigned (1:1:1) by computer to three different groups based on the study participant number: the Wu Qin Xi group (WQX), the strength exercise mixed with endurance exercise training group (SE), and the WQXSE hybrid exercise group incorporated the above two. Body composition and frailty-related physical fitness factors were measured before and after a 24-week intervention. The measurements included Body height, Body mass, Timed Up and Go Test (TUGT), grip strength assessment (GS), 6min walk test (6 min WT), and 10 m maximum walk speed (10 m MWS). Data were analyzed using repeated measures ANOVA to determine group and time interaction effects and machine learning models were used to predict program effectiveness.

RESULTS

A total of 163 participants completed the study, with 53.9% (n=88) of them being female. The two items, 10 m maximum walking speed (10 m MWS) and grip strength, were significantly affected by the interaction of group and time. Compared to the other two groups, the WQXSE group showed the most improvement in the item 10 m MWS. In addition, following 24 weeks of training, 68 (41.7%) of the initially frail older adults had reversed their frailty status. Among them, 19 (36.5%) were in the WQX group, 24 (44.4%) were in the WQXSE group, and 25 (43.9%) were in the SE group. The stacking model exhibited superior performance when compared to other algorithms.

CONCLUSION

A hybrid exercise regimen comprising the Wu Qin Xi routine and exercises focused on both strength and endurance holds the potential to yield greater improvements in the physical fitness of older adults, as well as reducing frailty. Leveraging a stacking model, it is possible to forecast the likelihood of older adults successfully reversing their frailty status following participation in a prevention exercise program.

Exercise and Nutritional Intervention for Physical Function of the Prefrail: A Systematic Review and Meta-Analysis

OBJECTIVES

The aim is to inspect the effects of exercise and nutritional intervention on prefrail older adults' physical function.

DESIGN

Systematic review and meta-analysis registered with PROSPERO (registration number: CRD42021261197).

SETTING AND PARTICIPANTS

Randomized controlled trials involving prefrail older adults who received exercise and/or nutritional interventions.

METHODS

Ovid MEDLINE, EMBASE, Cochrane Central Registry of Controlled Trials (CENTRAL), Web of Science, Clinical Trials, and PubMed were searched from inception to September 1, 2021. Primary outcomes were physical function, including physical performance, mobility, and grip strength. The short physical performance battery score and chair sit-to-stand test were used to assess the physical performance. Timed up and go and gait speed were applied to assess the mobility. Secondary outcomes were frailty status, weight, body mass index, Barthel index, and quality of life (Euro quality of life 5 dimension index values).

RESULTS

We included 16 randomized controlled trials comprising 1199 prefrail older adults (intervention group, n = 593; control group, n = 606). Exercise and nutritional interventions significantly improved the short physical performance battery score [n = 5, mean difference 0.81, 95% confidence interval (CI) 0.21‒1.42, I² = 62%], handgrip strength (n = 7, mean difference 1.52, 95% CI 0.70‒2.34, I² = 6%), and gait speed (n = 4, standard weighted mean difference -1.06, 95% CI -1.87 to -0.25, I² = 89%). There were no significant differences among the chair sit-to-stand test, timed up and go, weight, body mass index, and Barthel index.

CONCLUSIONS AND IMPLICATIONS

Our systematic review and meta-analysis shows that the receipt of exercise and nutritional intervention significantly improved physical function in prefrail older adults.

Effectiveness of a Hybrid Exercise Program on the Physical Abilities of Frail Elderly and Explainable Artificial-Intelligence-Based Clinical Assistance

Background: Due to the low physical fitness of the frail elderly, current exercise program strategies have a limited impact. Eight-form Tai Chi has a low intensity, but high effectiveness in the elderly. Inspired by it, we designed an exercise program that incorporates eight-form Tai Chi, strength, and endurance exercises, to improve physical fitness and reverse frailty in the elderly. Additionally, for the ease of use in clinical practice, machine learning simulations were used to predict the frailty status after the intervention. Methods: For 24 weeks, 150 frail elderly people completed the experiment, which comprised the eight-form Tai Chi group (TC), the strength and endurance training group (SE), and a comprehensive intervention combining both TC and SE (TCSE). The comparison of the demographic variables used one-way ANOVA for continuous data and the chi-squared test for categorical data. Two-way repeated measures analysis of variance (ANOVA) was performed to determine significant main effects and interaction effects. Eleven machine learning models were used to predict the frailty status of the elderly following the intervention. Results: Two-way repeated measures ANOVA results before the intervention, group effects of ten-meter maximum walking speed (10 m MWS), grip strength (GS), timed up and go test (TUGT), and the six-minute walk test (6 min WT) were not significant. There was a significant interaction effect of group × time in ten-meter maximum walking speed, grip strength, and the six-minute walk test. Post hoc tests showed that after 24 weeks of intervention, subjects in the TCSE group showed the greatest significant improvements in ten-meter maximum walking speed (p < 0.05) and the six-minute walk test (p < 0.05) compared to the TC group and SE group. The improvement in grip strength in the TCSE group (4.29 kg) was slightly less than that in the SE group (5.16 kg). There was neither a significant main effect nor a significant interaction effect for TUGT in subjects. The stacking model outperformed other algorithms. Accuracy and the F1-score were 67.8% and 71.3%, respectively. Conclusion: A hybrid exercise program consisting of eight-form Tai Chi and strength and endurance exercises can more effectively improve physical fitness and reduce frailty among the elderly. It is possible to predict whether an elderly person will reverse frailty following an exercise program based on the stacking model.

Exercise in Octogenarians: How Much Is Too Little?

The global population is rapidly aging, with predictions of many more people living beyond 85 years. Age-related physiological adaptations predispose to decrements in physical function and functional capacity, the rate of which can be accelerated by chronic disease and prolonged physical inactivity. Decrements in physical function exacerbate the risk of chronic disease, disability, dependency, and frailty with advancing age. Regular exercise positively influences health status, physical function, and disease risk in adults of all ages. Herein, we review the role of structured exercise training in the oldest old on cardiorespiratory fitness and muscular strength and power, attributes critical for physical function, mobility, and independent living. Expected final online publication date for the Annual Review of Medicine, Volume 73 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Effectiveness of physical activity interventions in older adults with frailty or prefrailty: a systematic review and meta-analysis

Background:

Methods:

Results:

Interpretation:

PROSPERO registration:

Sarcopenia as a Mediator of the Effect of a Gerontogymnastics Program on Cardiorespiratory Fitness of Overweight and Obese Older Women: A Randomized Controlled Trial

The objectives were to analyze the effect of a gerontogymnastics program on functional ability and fitness on overweight and obese older woman and to understand if sarcopenia mediates its effect. This randomized controlled trial involved 216 overweight and obese women. The experimental group (EG) carried out 12 weeks of a gerontogymnastics program. The assessment was of gait speed, cardiorespiratory fitness, functional capacity, and muscle strength. EG showed significant improvements in almost every test. When the effect of training was adjusted by gait speed, the improvement of the 6 min walk test (MWT) for the trained group was no longer significant (p = 0.127). The improvement of the 6 MWT was significantly and positively associated with the 10 m test (β = −10.087). After including the 10-m test in the equations, the association between the 6MWT and carrying out the training program decreased but remained significant (β = −19.904). The mediation analysis showed a significant, direct and indirect effect with a significant Sobel test value (z = 6.606 ± 7.733; p = 0.000). These results indicate that a gerontogymnastics program improves functional capacity and fitness; and the effect of a gerontogymnastics program on CRF is mediated by sarcopenia in older women who are overweight and obese.

Effects of concurrent aerobic and resistance exercise in frail and pre-frail older adults: A randomized trial of supervised versus home-based programs

BACKGROUND

This study aimed to investigate the effects of supervised and home-based exercise programs on older people with frailty or pre-frailty.

METHODS

A total of 146 community-dwelling participants aged 65 and older who were prefrail or frail were randomly allocated into supervised exercise (N = 74) and home exercise (N = 72) groups. The 3-month supervised exercise training consisted of 3 exercise sessions per week, was performed at a hospital and supervised by a physical therapist. Home exercise participants took instructions on exercise and illustrated exercise handouts. The baseline and 3-month follow-up measurements included body composition, strength of selected upper and lower limb muscle groups, grip and leg press strengths, and five physical performance tests. Mixed-model repeated-measures analysis was applied to determine whether two groups differ in terms of changes before and after the intervention and to compare within-group improvements.

RESULTS

After 3 months of supervised or home-based exercise, the average number of frailty criteria met and fat percentage decreased significantly. Strength of knee extensors, knee flexors and leg press improved significantly in supervised exercise group. In home-based exercise group, the strength of all muscle groups tested improved significantly, except for leg press strength. Walking speed improved in both groups, and timed-up-and-go and timed chair rise tests improved significantly only in supervised exercise group.

CONCLUSIONS

Three-month supervised or home-based exercise improved walking speed and strength of the limb muscles. Supervised group showed more improvements in the physical performance tests compared with home-based exercise group.

Multicomponent Exercise Program Reduces Frailty and Inflammatory Biomarkers and Improves Physical Performance in Community-Dwelling Older Adults: A Randomized Controlled Trial

The efficacy of exercise to reverse frailty in the aging population has not been extensively investigated. This study aimed to investigate the effectiveness of a multicomponent exercise program (MCEP) on frailty, physical performance (handgrip strength, Berg Balance Scale (BBS), Timed Up and Go test (TUG), and VO2Max), blood biomarkers (Interleukin-6 (IL-6) and C-reactive protein (CRP)) in frail older adults. A randomized controlled trial using an allocation concealment method, included 64 older adults (77.78 ± 7.24 years), were divided into two parallel groups using block randomization: an MCEP group (n = 32) and a control group (n = 32). The combined center- and home-based MCEP training consisted of chair aerobic, resistance, and balance, which was carried out 3 days per week for 24 weeks. A mixed model repeated measure ANOVA demonstrated significant interaction effects of group x time for BBS, TUG and frailty scores (p < 0.001). Additionally, the post-hoc analysis revealed that the MCEP group showed significantly improved BBS, TUG, and frailty scores (p < 0.01), at both 12- and 24-weeks. When compared with controls at 12-weeks, the MCEP group decreased IL-6 and CRP levels (p < 0.05). The combined center- and home-based MCEP were effective in reversing frailty to pre-frailty and improving physical performance especially balance in the older population.

Effectiveness of exercise interventions on physical function in community-dwelling frail older people: an umbrella review of systematic reviews

OBJECTIVES

This umbrella review aimed to determine the effectiveness of exercise interventions, alone or in combination with other interventions, in improving physical function in community-dwelling older people identified as pre-frail or frail.

INTRODUCTION

Exercise is said to have a positive impact on muscle mass and strength which improves physical function and hence is beneficial for the treatment of frailty. Several systematic reviews discuss the effects of exercise interventions on physical function parameters, such as strength, mobility, gait, balance and physical performance, and indicate that multi-component exercise, including resistance, aerobic, balance and flexibility training, appears to be the best way in which to improve physical function parameters in frail older people. However, there is still uncertainty as to which exercise characteristics (type, frequency, intensity, duration and combinations) are the most effective and sustainable over the long-term.

INCLUSION CRITERIA

Participants were adults, 60 years or over, living in the community and identified as pre-frail or frail. Quantitative systematic reviews, with or without meta-analysis that examined the effectiveness of exercise interventions of any form, duration, frequency and intensity, alone or in combination with other interventions designed to alter physical function parameters in frail older people, were considered. The quantitative outcome measures were physical function, including muscular strength, gait, balance, mobility and physical performance.

METHODS

An iterative search strategy for ten bibliometric databases and gray literature was developed. Critical appraisal of seven systematic reviews was conducted independently by two reviewers using a standard Joanna Briggs Institute tool. Data was extracted independently by two reviewers using a standard Joanna Briggs Institute data extraction tool and summarized using a narrative synthesis approach.

RESULTS

Seven systematic reviews were included in this umbrella review, with a total of 58 relevant randomized controlled trials and 6927 participants. Five systematic reviews examined the effects of exercise only, while two systematic reviews reported on exercise in combination with a nutritional approach, including protein supplementations, as well as fruit and dairy products. The average exercise frequency was 2-3 times per week (mean 3.0 ± 1.5 times per week; range 1-7 weekly) for 10-90 minutes per session (mean of 52.0 ± 16.5 mins) and a total duration of 5-72 weeks with the majority lasting a minimum of 2.5 months (mean 22.7 ± 17.7 weeks). Multi-component exercise interventions can currently be recommended for pre-frail and frail older adults to improve muscular strength, gait speed, balance and physical performance, including resistance, aerobic, balance and flexibility tasks. Resistance training alone also appeared to be beneficial, in particular for improving muscular strength, gait speed and physical performance. Other types of exercise were not sufficiently studied and their effectiveness is yet to be established.

CONCLUSIONS

Interventions for pre-frail and frail older adults should include multi-component exercises, including in particular resistance training, as well as aerobic, balance and flexibility tasks. Future research should adopt a consistent definition of frailty and investigate the effects of other types of exercise alone or in combination with nutritional interventions so that more specific recommendations can be made.

Associations Between Skeletal Muscle Mass, Grip Strength, and Physical and Cognitive Functions in Elderly Women: Effect of Exercise with Resistive Theraband

PURPOSE

The purpose of this study was to identify the relationships between muscle mass, muscle strength, and physical and cognitive functions and to examine the effects of resistive Theraband® exercise on sarcopenia-associated variables in the older population.

METHODS

A total of 28 elderly women (age: 69.90 ± 0.8 years) participated in this study, 15 of whom underwent elastic band exercise for 1 hour per day, twice per week for 8 weeks. The correlation analysis was conducted to identify the associations between body composition, skeletal muscle mass indices, grip strength, and physical and cognitive functions. All variables were assessed at baseline and post-exercise.

RESULTS

Skeletal muscle mass was significantly associated with grip strength and physical function. Gait speed was positively correlated with grip strength and physical function, but not with cognitive function. Theraband® exercise significantly improved gait speed and physical function.

CONCLUSION

The present data suggest that skeletal muscle mass is highly correlated with grip strength and physical function. Eight weeks of resistive Theraband® exercise favorably affects sarcopenia by improving gait speed and mobility of elderly women.

Management of Frailty at Individual Level: Narrative Review of Physical Activity from the European Perspective of Joint Action on Frailty - JA Advantage

Introduction

This paper aimed to review the effect of physical activity and exercise in frail older persons. As the process which leads to frailty and disability can be slowed down or even completely reversed, it can be appropriate for early interventions.

Methodology

A literature search was conducted in the following databases: PubMed, Cochrane, Embase, Cinahl and UpToDate. The criterion in selecting the literature was that articles were published from 2002 to 2017. From 620,043 initial hits, 25 publications were selected.

Results

Physical activity and exercise in frail elderly are effective and relatively safe and may reverse frailty.

Conclusion

Different exercise interventions in frail elderly persons can increase strength and power, improve balance and reduce fall incidence resulting in greater quality of life. From this perspective, physical exercise interventions should become daily routine in frail elderly persons.

The historical context and scientific legacy of John O. Holloszy

John O. Holloszy, as perhaps the world's preeminent exercise biochemist/physiologist, published >400 papers over his 50+ year career, and they have been cited >41,000 times. In 1965 Holloszy showed for the first time that exercise training in rodents resulted in a doubling of skeletal muscle mitochondria, ushering in a very active era of skeletal muscle plasticity research. He subsequently went on to describe the consequences of and the mechanisms underlying these adaptations. Holloszy was first to show that muscle contractions increase muscle glucose transport independent of insulin, and he studied the mechanisms underlying this response throughout his career. He published important papers assessing the impact of training on glucose and insulin metabolism in healthy and diseased humans. Holloszy was at the forefront of rodent studies of caloric restriction and longevity in the 1980s, following these studies with important cross-sectional and longitudinal caloric restriction studies in humans. Holloszy was influential in the discipline of cardiovascular physiology, showing that older healthy and diseased populations could still elicit beneficial cardiovascular adaptations with exercise training. Holloszy and his group made important contributions to exercise physiology on the effects of training on numerous metabolic, hormonal, and cardiovascular adaptations. Holloszy's outstanding productivity was made possible by his mentoring of ~100 postdoctoral fellows and substantial NIH grant funding over his entire career. Many of these fellows have also played critical roles in the exercise physiology/biochemistry discipline. Thus it is clear that exercise biochemistry and physiology will be influenced by John Holloszy for numerous years to come.

Insights into the mechanism of paradoxical low-flow, low-pressure gradient severe aortic stenosis: association with reduced O2 consumption by the whole body

The mechanism of reduced stroke volume index (SVi) in paradoxical low-flow, low-pressure gradient (PLFLPG) aortic stenosis (AS) remains unclarified. Guyton et al. ( 21 ) demonstrated that SVi is determined by whole body O₂ consumption (V̇o₂) in many subjects, including patients with heart disease. We hypothesized that reduced SVi in PLFLPG AS is associated with reduced V̇o₂ by the whole body. This study investigated the relationship between V̇o₂, SVi, and AS severity in patients with AS to examine the association between reduced V̇o₂ and PLFLPG AS. In 59 patients (24 men and 35 women, mean age: 78 ± 7 yr old) with severe AS, SVi, AS severity, and type were evaluated by echocardiography, and V̇o₂ was measured by the fraction of O₂ in expired gases. SVi and V̇o₂ were significantly decreased in 20 patients with PLFLPG AS compared with 39 patients with non-PLFLPG AS (30 ± 4 vs. 41 ± 7 ml/m² and 2.4 ± 0.5 vs. 3.0 ± 0.5 ml·min^-1·kg^-1, respectively, P < 0.01). The SVi-to-V̇o₂ ratio was not different between the two groups (13.1 ± 2.6 vs. 13.6 ± 2.1, not significant). SVi was independently correlated with V̇o₂ ( r = 0.74, P < 0.01) but not with the aortic valve area index. Categorized PLFLPG AS was also significantly associated with reduced V̇o₂ ( P < 0.001). PLFLPG AS is associated with reduced V̇o₂ by the whole body, which may offer insights into the mechanism of PLFLPG AS. NEW & NOTEWORTHY Paradoxical low-flow, low-pressure gradient severe aortic stenosis (PLFLPG AS) is an important and problematic subtype, and its central pathophysiology with reduced stroke volume is yet to be clarified. We hypothesized and subsequently clarified that reduced stroke volume in PLFLPG AS is associated with reduced O₂ consumption by the whole body. This study suggests important insights into the mechanism of PLFLPG AS and may further promote studies to investigate further mechanisms and novel treatment.

Making More of IT: Enabling Intensive Motor Cognitive Rehabilitation Exercises in Geriatrics Using Information Technology Solutions

Although the health benefits of physical activity and exercise for older people are well established, a largely sedentary lifestyle still prevails in ageing western societies. Finding new ways to make exercise more accessible and acceptable for older adults must be developed to fully unleash its potential in preventing and weakening age-related physical and cognitive decline. Existing barriers to implement effective exercise-based treatment plans include motivational reservations on both the clinician's and patient's side, but also physical limitations caused by disease or deconditioning. Particularly in the more senior population, debilitating conditions do not allow adherence to currently recommended exercise regimes. A major rethinking of age- and user-adapted exercise is overdue. The high intensities required for physical and mental adaptations must be modifiable and personalized according to the functional status of each patient. Emerging information and communication technologies (ICT) have brought forward a plethora of attractive solutions for smart and adapted exercise, but there remains a vast gap between technological advancement and clinical relevance. Where in the beginning ICT for active ageing mainly focussed on aspects of usability and user experience, the current status of IT as applied in ageing populations noticeably shifted toward new services, applications, and devices that can be offered with the aim to prevent, compensate, care, and/or enhance daily life functioning of senior citizens. In this perspective paper, we aim to summarize the current state of the art in ICT-based interventions aimed at improved motor-cognitive control and make suggestions about how these could be combined with high-intensive interval exercise regimes to make rehabilitation for the impaired older adults more effective, and more fun.

Effectiveness of Multimodal Training on Functional Capacity in Frail Older People: A Meta-Analysis of Randomized Controlled Trials

In this meta-analysis, we investigated the effect of resistance training (RT) alone or included in a multimodal training on physical frailty outcomes, and whether different variables of RT prescription affect these outcomes. We identified 15 relevant studies searching through MEDLINE, Cochrane Central Register of Controlled Trials, SPORTDiscus, and PEDro database. Postintervention standardized mean difference scores were computed and combined using fixed effects meta-analysis. Analyses have shown positive effects of interventions on maximum strength, gait speed, and Timed Up and Go test. Further analyses have shown significant greater effect of shorter periods on maximum strength. Regarding RT prescription, percentage of one-repetition maximum showed significant effect on physical variables, whereas RT based on rate of perceived effort presented lower effect in the Timed Up and Go test. Although multimodal training is an effective intervention to increase physical capacity, caution should be taken regarding the period and the method to control RT intensity to optimize enhancements in frail older people.

Peak exercise stroke volume effects on cognitive impairment in community-dwelling people with preserved ejection fraction

AIMS

The association of vascular dysfunction and amyloid beta deposition attracted attentions for its relationship with cognitive decline. Previous studies show the correlation between the declined cardiac function and the cognitive impairment. In the present study, we analysed the association between cognitive functions and cardiac parameters in community-dwelling people with preserved ejection fraction without heart failure.

METHODS AND RESULTS

Subjects were 108 Japanese community-dwelling middle-aged and older adults with preserved ejection fraction (25 men and 83 women; mean age 74.7 years). Cardiac functional parameters at rest were assessed with B-type natriuretic peptide and echocardiography. The cardiopulmonary exercise test was used to test these parameters during exercise. Cognitive function was assessed with the Japanese version of the Montreal Cognitive Assessment (MoCA-J). Other indices were assessed biochemically, physiologically, and physically. There were significant correlations between MoCA-J score and age (r = -0.388), peak oxygen uptake (VO₂ , r = 0.201), peak VO₂ /heart rate (HR, r = 0.243), peak VO₂ /weight (r = 0.244), peak metabolic equivalents (r = 0.244), usual walking speed (r = -0.200), and the Timed Up and Go test (r = -0.230). Multiple linear regression analysis showed peak VO₂ /HR was an independent determinant of MoCA-J score after adjusting for potential confounders (B = 0.424). After 6 months of exercise training with 64 subjects, we found that the per cent change of peak VO₂ /HR was related to the per cent change of MoCA-J score (r = 0.296).

CONCLUSIONS

These results suggested that peak VO₂ /HR (an index of stroke volume at peak exercise) might be associated with cognitive impairment based on the vascular cascade hypothesis.

Relationship between hand grip strength and peak VO2 in community-dwelling elderly outpatients

Background: Hand grip strength and peak oxygen uptake (VO2) are important components of frailty. However, the relationship between these two variables among community-dwelling elderly people is still unclear. The present study aimed to investigate this relationship.Methods: Participants were 190 Japanese community-dwelling elderly outpatients (61 men and 129 women, mean age 78.0 years). Hand grip strength of participants’ dominant hand was measured using a Smedley-type hand dynamometer. Peak VO2 levels were assessed with a cardiopulmonary exercise test. Skeletal muscle mass index (SMI) and usual walking speed were assessed physiologically and physically. Sample size was calculated using G*Power 3.1.9.2.Results: There were significant correlations between hand grip strength and age (r = −0.22), peak VO2 (r = 0.40), SMI (r = 0.51), and usual walking speed (r = 0.29). There were significant differences in age, peak VO2 and SMI after participants were divided into normal and low hand grip strength groups according to the Asian Working Group for Sarcopenia threshold, whether both sexes were combined or considered separately. Multiple logistic regression analysis showed that peak VO2, SMI and age were independent determinants of hand grip strength after adjusting for potential confounders (Exp(B) = 0.871; 0.475; 1.065). Longitudinal analysis after 6 months of exercise training showed the percentage of change in hand grip strength and peak VO2 were correlated positively (r = 0.22) for 92 participants. Conclusion: Peak VO2 is independently associated with hand grip strength among community-dwelling elderly outpatients.  

[Effectiveness of physical exercise on fitness in frail older adults: A systematic review of randomised trials]

Performing exercise to maintain a good physical condition is crucial to improve and prevent frailty in older adults. The aim of this review was to assess the beneficial effects of physical exercise on fitness in frail older adults. A thorough literature search of randomised clinical trials (RCT) in the last 15 years was performed on different electronic databases. The methodological assessment of studies was obtained using the PEDro scale. Ten RCT were included, providing a final sample of 1,130 individuals. Scores on the PEDro scale ranged from 5 to 8/10. Multicomponent training programs seem to be the best strategy to improve fitness outcomes. Further studies should be performed in order to optimise the design of supervised exercise programs, and further research is needed in hospital and institutionalised settings.

Relationship between skeletal muscle mass and cardiac function during exercise in community-dwelling older adults

Aims

This study aimed to investigate the relationship between skeletal muscle mass and cardiac functional parameters in older adults during cardiopulmonary exercise testing (CPET).

Methods and results

Sixty‐three Japanese community‐dwelling older adults were enrolled (20 men and 43 women; mean age 80 years, range 65–97 years). Cardiac functional parameters during exercise were assessed using CPET. Skeletal muscle mass index (SMI) was calculated by dividing the appendicular lean mass (measured using dual‐energy X‐ray absorptiometry) by height in metres squared. Subjects were divided into two groups: men with SMI ≥ 7.0 kg/m² and women with SMI ≥ 5.4 kg/m² (non‐sarcopenic group); or men with SMI < 7.0 kg/m² and women with SMI < 5.4 kg/m² (sarcopenic group). There were significant positive correlations between SMI and peak oxygen uptake (VO₂) (r = 0.631, P < 0.001), and between SMI and peak VO₂/heart rate (HR) (r = 0.683, P < 0.001). However, only peak VO₂/HR significantly differed between groups in both sexes. Multiple linear regression analyses with peak VO₂/HR as a dependent variable showed that SMI was the only independent determinant after adjusting for potential confounders. After 4 month follow‐up of 47 participants, there was still a significant positive correlation between SMI and peak VO₂/HR (r = 0.567, P < 0.001), and between percent change of SMI and percent change of peak VO₂/HR (r = 0.305, P < 0.05).

Conclusions

Peak VO₂/HR, an index of stroke volume at peak exercise, was associated with SMI. This indicates that skeletal muscle mass might affect cardiac function during exercise.

Exercise prescription to reverse frailty

Frailty is a clinical geriatric syndrome caused by physiological deficits across multiple systems. These deficits make it challenging to sustain homeostasis required for the demands of everyday life. Exercise is likely the best therapy to reverse frailty status. Literature to date suggests that pre-frail older adults, those with 1–2 deficits on the Cardiovascular Health Study-Frailty Phenotype (CHS-frailty phenotype), should exercise 2–3 times a week, for 45–60 min. Aerobic, resistance, flexibility, and balance training components should be incorporated but resistance and balance activities should be emphasized. On the other hand, frail (CHS-frailty phenotype ≥ 3 physical deficits) older adults should exercise 3 times per week, for 30–45 min for each session with an emphasis on aerobic training. During aerobic, balance, and flexibility training, both frail and pre-frail older adults should work at an intensity equivalent to a rating of perceived exertion of 3–4 (“somewhat hard”) on the Borg CR10 scale. Resistance-training intensity should be based on a percentage of 1-repetition estimated maximum (1RM). Program onset should occur at 55% of 1RM (endurance) and progress to higher intensities of 80% of 1RM (strength) to maximize functional gains. Exercise is the medicine to reverse or mitigate frailty, preserve quality of life, and restore independent functioning in older adults at risk of frailty.

The effect of 1 year of Alagebrium and moderate-intensity exercise training on left ventricular function during exercise in seniors: a randomized controlled trial

Sedentary aging leads to left ventricular (LV) and vascular stiffening due in part to advanced glycation end-products (AGEs) cross-linking of extracellular matrix proteins. Vigorous lifelong exercise ameliorates age-related cardiovascular (CV) stiffening and enhances exercise LV function, although this effect is limited when exercise is initiated later in life. We hypothesized that exercise training might be more effective at improving the impact of age-related CV stiffening during exercise when combined with an AGE cross-link breaker (Alagebrium). Sixty-two seniors (≥60 yr) were randomized into four groups: sedentary + placebo, sedentary + Alagebrium, exercise + placebo, and exercise + Alagebrium for 1 yr. Moderate-intensity aerobic exercise was performed 3-4 sessions/wk; controls underwent similar frequency of yoga/balance training. Twenty-four similarly-aged, lifelong exercisers (4-5 sessions/wk) served as a comparator for the effect of lifelong exercise on exercising LV function. Oxygen uptake (Douglas bags), stroke index (SI; acetylene rebreathing), and effective arterial elastance (Ea) were collected at rest and submaximal and maximal exercise. Maximum O2 uptake (23 ± 5 to 25 ± 6 ml·kg(-1)·min(-1)) increased, while SI (35 ± 11 to 39 ± 12 ml/m(2)) and Ea (4.0 ± 1.1 to 3.7 ± 1.2 mmHg·ml(-1)·m(-2)) were improved across all conditions with exercise, but remained unchanged in controls (exercise × time, P ≤ 0.018). SI or Ea were not affected by Alagebrium (medication × time, P ≥ 0.468) or its combination with exercise (interaction P ≥ 0.252). After 1 yr of exercise plus Alagebrium, exercise SI and Ea remained substantially below that of lifelong exercisers (15-24 and 9-22%, respectively, P ≤ 0.415). In conclusion, Alagebrium plus exercise had no synergistic effect on exercise LV function and failed to achieve levels associated with lifelong exercise, despite a similar exercise frequency.

Frailty and sarcopenia as the basis for the phenotypic manifestation of chronic diseases in older adults

Frailty is a functional status that precedes disability and is characterized by decreased functional reserve and increased vulnerability. In addition to disability, the frailty phenotype predicts falls, institutionalization, hospitalization and mortality. Frailty is the consequence of the interaction between the aging process and some chronic diseases and conditions that compromise functional systems and finally produce sarcopenia. Many of the clinical manifestations of frailty are explained by sarcopenia which is closely related to poor physical performance. Reduced regenerative capacity, malperfusion, oxidative stress, mitochondrial dysfunction and inflammation compose the sarcopenic skeletal muscle alterations associated to the frailty phenotype. Inflammation appears as a common determinant for chronic diseases, sarcopenia and frailty. The strategies to prevent the frailty phenotype include an adequate amount of physical activity and exercise as well as pharmacological interventions such as myostatin inhibitors and specific androgen receptor modulators. Cell response to stress pathways such as Nrf2, sirtuins and klotho could be considered as future therapeutic interventions for the management of frailty phenotype and aging-related chronic diseases.

Altered left ventricular performance in aging physically active mice with an ankle sprain injury

We assessed the impact of differing physical activity levels throughout the lifespan, using a musculoskeletal injury model, on the age-related changes in left ventricular (LV) parameters in active mice. Forty male mice (CBA/J) were randomly placed into one of three running wheel groups (transected CFL group, transected ATFL/CFL group, SHAM group) or a SHAM Sedentary group (SHAMSED). Before surgery and every 6 weeks after surgery, LV parameters were measured under 2.5 % isoflurane inhalation. Group effects for daily distance run was significantly greater for the SHAM and lesser for the ATLF/CFL mice (p = 0.013) with distance run decreasing with age for all mice (p < 0.0001). Beginning at 6 months of age, interaction (group × age) was noted with LV posterior wall thickness-to-radius ratios (h/r) where h/r increased with age in the ATFL/CFL and SHAMSED mice while the SHAM and CFL mice exhibited decreased h/r with age (p = 0.0002). Passive filling velocity (E wave) was significantly greater in the SHAM mice and lowest for the ATFL/CFL and SHAMSED mice (p < 0.0001) beginning at 9 months of age. Active filling velocity (A wave) was not different between groups (p = 0.10). Passive-to-active filling velocity ratio (E/A ratio) was different between groups (p < 0.0001), with higher ratios for the SHAM mice and lower ratios for the ATFL/CFL and SHAMSED mice in response to physical activity beginning at 9 months of age. Passive-to-active filling velocity ratio decreased with age (p < 0.0001). Regular physical activity throughout the lifespan improved LV structure, passive filling velocity, and E/A ratio by 6 to 9 months of age and attenuated any negative alterations throughout the second half of life. The diastolic filling differences were found to be significantly related to the amount of activity performed by 9 months and at the end of the lifespan.

Exercise attenuates the major hallmarks of aging

Regular exercise has multi-system anti-aging effects. Here we summarize how exercise impacts the major hallmarks of aging. We propose that, besides searching for novel pharmaceutical targets of the aging process, more research efforts should be devoted to gaining insights into the molecular mediators of the benefits of exercise and to implement effective exercise interventions for elderly people.

Physical Exercise as Therapy for Frailty

Longitudinal studies demonstrate that regular physical exercise extends longevity and reduces the risk of physical disability. Decline in physical activity with aging is associated with a decrease in exercise capacity that predisposes to frailty. The frailty syndrome includes a lowered activity level, poor exercise tolerance, and loss of lean body and muscle mass. Poor exercise tolerance is related to aerobic endurance. Aerobic endurance training can significantly improve peak oxygen consumption by ∼10-15%. Resistance training is the best way to increase muscle strength and mass. Although the increase in muscle mass in response to resistance training may be attenuated in frail older adults, resistance training can significantly improve muscle strength, particularly in institutionalized patients, by ∼110%. Because both aerobic and resistance training target specific components of frailty, studies combining aerobic and resistance training provide the most promising evidence with respect to successfully treating frailty. At the molecular level, exercise reduces frailty by decreasing muscle inflammation, increasing anabolism, and increasing muscle protein synthesis. More studies are needed to determine which exercises are best suited, most effective, and safe for this population. Based on the available studies, an individualized multicomponent exercise program that includes aerobic activity, strength exercises, and flexibility is recommended to treat frailty.

Effect of endurance and/or strength training on muscle fiber size, oxidative capacity, and capillarity in hemodialysis patients

We previously reported reduced limb muscle fiber succinate dehydrogenase (SDH) activity and capillarity density and increased cross-sectional areas (CSAs) of all fiber types in maintenance hemodialysis (MHD) patients compared with matched controls that may contribute to their effort intolerance and muscle weakness. This study evaluated whether endurance training (ET), strength training (ST), or their combination (EST) alters these metabolic and morphometric aberrations as a mechanism for functional improvement. Five groups were evaluated: 1) controls; 2) MHD/no training; 3) MHD/ET; 4) MHD/ST; and 5) MHD/EST. Training duration was 21.5 ± 0.7 wk. Vastus lateralis muscle biopsies were obtained after HD at baseline and at study end. Muscle fibers were classified immunohistochemically, and fiber CSAs were computed. Individual fiber SDH activity was determined by a microdensitometric assay. Capillaries were identified using antibodies against endothelial cells. Type I and IIA fiber CSAs decreased significantly (10%) with EST. In the ET group, SDH activity increased 16.3% in type IIA and 19.6% in type IIX fibers. Capillary density increased significantly by 28% in the EST group and 14.3% with ET. The number of capillaries surrounding individual fiber type increased significantly in EST and ET groups. Capillary-to-fiber ratio increased significantly by 11 and 9.6% in EST and ET groups, respectively. We conclude that increments in capillarity and possibly SDH activity in part underlie improvements in endurance of MHD patients posttraining. We speculate that improved specific force and/or neural adaptations to exercise underlie improvements in limb muscle strength of MHD patients.

Social vulnerability and survival across levels of frailty in the Honolulu-Asia Aging Study

PURPOSE

we evaluated mortality risk in relation to social vulnerability across levels of frailty among a cohort of older Japanese-American men.

METHODS

in secondary analysis of the Honolulu-Asia Aging Study (HAAS), participants (n = 3,271) were aged 72-93 years at baseline. A frailty index (FI) created using 58 potential health deficits to quantify participants' frailty level at baseline, with four frailty strata: 0.0 < FI ≤ 0.1 (n = 1,074); 0.1 < FI ≤ 0.20 (n = 1,549); 0.2 < FI ≤ 0.30 (n = 472); FI > 0.3 (n = 176). Similarly, a social vulnerability index was created using 19 self-reported social deficits. Cox proportional hazard modelling was employed to estimate the impact of social vulnerability across the four levels of frailty, accounting for age, smoking, alcohol use and variation in health deficits within each frailty level.

RESULTS

for the fittest participants, social vulnerability was associated with mortality (hazards ratio (HR) = 1.04, 95% confidence interval (CI) = 1.01, 1.07; P value = 0.008). Similarly, for those considered at risk for frailty, each social deficit was associated with a 5% increased risk of mortality. For frail individuals, the Cox regression analyses indicated that social vulnerability was not significantly associated with mortality (0.2 < FI ≤ 0.3: HR = 1.016, 95% CI = 0.98, 1.06; P value = 0.442; FI > 0.3: HR = 0.98, 95% CI = 0.93, 1.04).

CONCLUSIONS

for the fittest and at-risk HAAS participants, the accumulation of social deficits was associated with significant increases in mortality risk. For frail individuals (FI > 0.20), the estimation of mortality risk may depend more so on intrinsic factors related to their health.

Strength and endurance training prescription in healthy and frail elderly

Aging is associated with declines in the neuromuscular and cardiovascular systems, resulting in an impaired capacity to perform daily activities. Frailty is an age-associated biological syndrome characterized by decreases in the biological functional reserve and resistance to stressors due to changes in several physiological systems, which puts older individuals at special risk of disability. To counteract the neuromuscular and cardiovascular declines associated with aging, as well as to prevent and treat the frailty syndrome, the strength and endurance training seems to be an effective strategy to improve muscle hypertrophy, strength and power output, as well as endurance performance. The first purpose of this review was discuss the neuromuscular adaptations to strength training, as well as the cardiovascular adaptations to endurance training in healthy and frail elderly subjects. In addition, the second purpose of this study was investigate the concurrent training adaptations in the elderly. Based on the results found, the combination of strength and endurance training (i.e., concurrent training) performed at moderate volume and moderate to high intensity in elderly populations is the most effective way to improve both neuromuscular and cardiorespiratory functions. Moreover, exercise interventions that include muscle power training should be prescribed to frail elderly in order to improve the overall physical status of this population and prevent disability.

Strength and endurance training prescription in healthy and frail elderly

Aging is associated with declines in the neuromuscular and cardiovascular systems, resulting in an impaired capacity to perform daily activities. Frailty is an age-associated biological syndrome characterized by decreases in the biological functional reserve and resistance to stressors due to changes in several physiological systems, which puts older individuals at special risk of disability. To counteract the neuromuscular and cardiovascular declines associated with aging, as well as to prevent and treat the frailty syndrome, the strength and endurance training seems to be an effective strategy to improve muscle hypertrophy, strength and power output, as well as endurance performance. The first purpose of this review was discuss the neuromuscular adaptations to strength training, as well as the cardiovascular adaptations to endurance training in healthy and frail elderly subjects. In addition, the second purpose of this study was investigate the concurrent training adaptations in the elderly. Based on the results found, the combination of strength and endurance training (i.e., concurrent training) performed at moderate volume and moderate to high intensity in elderly populations is the most effective way to improve both neuromuscular and cardiorespiratory functions. Moreover, exercise interventions that include muscle power training should be prescribed to frail elderly in order to improve the overall physical status of this population and prevent disability.

Exercise-training-induced changes in metabolic capacity with age: the role of central cardiovascular plasticity

Although aging is typically associated with a decline in maximal oxygen consumption (VO2max), young and old subjects, of similar initial muscle metabolic capacity, increased quadriceps VO2max equally when this small muscle mass was trained in isolation. As it is unclear if this preserved exercise-induced plasticity with age is still evident with centrally challenging whole body exercise, we assessed maximal exercise responses in 13 young (24 ± 2 years) and 13 old (60 ± 3 years) males, matched for cycling VO2max (3.82 ± 0.66 and 3.69 ± 0.30 L min(-1), respectively), both before and after 8 weeks of high aerobic intensity cycle exercise training. As a consequence of the training both young and old significantly improved VO2max (13 ± 6 vs. 6 ± 7 %) and maximal power output (20 ± 6 vs. 10 ± 6 %, respectively) from baseline, however, the young exhibited a significantly larger increase than the old. Similarly, independently assessed maximal cardiac output (Q max) tended to increase more in the young (16 ± 14 %) than in the old (11 ± 12 %), with no change in a-vO2 difference in either group. Further examination of the components of Q max provided additional evidence of reduced exercise-induced plasticity in both maximal heart rate (young -3 %, old 0 %) and stroke volume (young 19 ± 15, old 11 ± 11 %) in the old. In combination, these findings imply that limited central cardiovascular plasticity may be responsible, at least in part, for the attenuated response to whole body exercise training with increasing age.

Effects of different exercise interventions on risk of falls, gait ability, and balance in physically frail older adults: a systematic review

The aim of this review was to recommend training strategies that improve the functional capacity in physically frail older adults based on scientific literature, focusing specially in supervised exercise programs that improved muscle strength, fall risk, balance, and gait ability. Scielo, Science Citation Index, MEDLINE, Scopus, Sport Discus, and ScienceDirect databases were searched from 1990 to 2012. Studies must have mentioned the effects of exercise training on at least one of the following four parameters: Incidence of falls, gait, balance, and lower-body strength. Twenty studies that investigated the effects of multi-component exercise training (10), resistance training (6), endurance training (1), and balance training (3) were included in the present revision. Ten trials investigated the effects of exercise on the incidence of falls in elderly with physical frailty. Seven of them have found a fewer falls incidence after physical training when compared with the control group. Eleven trials investigated the effects of exercise intervention on the gait ability. Six of them showed enhancements in the gait ability. Ten trials investigated the effects of exercise intervention on the balance performance and seven of them demonstrated enhanced balance. Thirteen trials investigated the effects of exercise intervention on the muscle strength and nine of them showed increases in the muscle strength. The multi-component exercise intervention composed by strength, endurance and balance training seems to be the best strategy to improve rate of falls, gait ability, balance, and strength performance in physically frail older adults.

The effect of lifelong exercise dose on cardiovascular function during exercise

An increased "dose" of endurance exercise training is associated with a greater maximal oxygen uptake (Vo2max), a larger left ventricular (LV) mass, and improved heart rate and blood pressure control. However, the effect of lifelong exercise dose on metabolic and hemodynamic response during exercise has not been previously examined. We performed a cross-sectional study on 101 (69 men) seniors (60 yr and older) focusing on lifelong exercise frequency as an index of exercise dose. These included 27 who had performed ≤ 2 exercise sessions/wk (sedentary), 25 who performed 2-3 sessions/wk (casual), 24 who performed 4-5 sessions/wk (committed) and 25 who performed ≥ 6 sessions/wk plus regular competitions (Masters athletes) over at least the last 25 yr. Oxygen uptake and hemodynamics [cardiac output, stroke volume (SV)] were collected at rest, two levels of steady-state submaximal exercise, and maximal exercise. Doppler ultrasound measures of LV diastolic filling were assessed at rest and during LV loading (saline infusion) to simulate increased LV filling. Body composition, total blood volume, and heart rate recovery after maximal exercise were also examined. Vo2max increased in a dose-dependent manner (P < 0.05). At maximal exercise, cardiac output and SV were largest in committed exercisers and Masters athletes (P < 0.05), while arteriovenous oxygen difference was greater in all trained groups (P < 0.05). At maximal exercise, effective arterial elastance, an index of ventricular-arterial coupling, was lower in committed exercisers and Masters athletes (P < 0.05). Doppler measures of LV filling were not enhanced at any condition, irrespective of lifelong exercise frequency. These data suggest that performing four or more weekly endurance exercise sessions over a lifetime results in significant gains in Vo2max, SV, and heart rate regulation during exercise; however, improved SV regulation during exercise is not coupled with favorable effects on LV filling, even when the heart is fully loaded.

New records in aerobic power among octogenarian lifelong endurance athletes

We examined whole body aerobic capacity and myocellular markers of oxidative metabolism in lifelong endurance athletes [n = 9, 81 ± 1 yr, 68 ± 3 kg, body mass index (BMI) = 23 ± 1 kg/m(2)] and age-matched, healthy, untrained men (n = 6; 82 ± 1 y, 77 ± 5 kg, BMI = 26 ± 1 kg/m(2)). The endurance athletes were cross-country skiers, including a former Olympic champion and several national/regional champions, with a history of aerobic exercise and participation in endurance events throughout their lives. Each subject performed a maximal cycle test to assess aerobic capacity (VO(2max)). Subjects had a resting vastus lateralis muscle biopsy to assess oxidative enzymes (citrate synthase and βHAD) and molecular (mRNA) targets associated with mitochondrial biogenesis [peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) and mitochondrial transcription factor A (Tfam)]. The octogenarian athletes had a higher (P < 0.05) absolute (2.6 ± 0.1 vs. 1.6 ± 0.1 l/min) and relative (38 ± 1 vs. 21 ± 1 ml·kg(-1)·min(-1)) VO(2max), ventilation (79 ± 3 vs. 64 ± 7 l/min), heart rate (160 ± 5 vs. 146 ± 8 beats per minute), and final workload (182 ± 4 vs. 131 ± 14 W). Skeletal muscle oxidative enzymes were 54% (citrate synthase) and 42% (βHAD) higher (P < 0.05) in the octogenarian athletes. Likewise, basal PGC-1α and Tfam mRNA were 135% and 80% greater (P < 0.05) in the octogenarian athletes. To our knowledge, the VO(2max) of the lifelong endurance athletes is the highest recorded in humans >80 yr of age and comparable to nonendurance trained men 40 years younger. The superior cardiovascular and skeletal muscle health profile of the octogenarian athletes provides a large functional reserve above the aerobic frailty threshold and is associated with lower risk for disability and mortality.

Salzburg Skiing for the Elderly Study: changes in cardiovascular risk factors through skiing in the elderly

Numerous studies have shown that treatment of the modifiable cardiovascular risk factors (CVRF) results in a decreased risk to suffer from stroke or myocardial infarction. Despite the fact that exercise training is a potent treatment choice for CVRF, this is the first randomized study to assess the effects of alpine skiing on CVRF in elderly skiers. Subjects (n=42) were randomized into an intervention group (IG; n=22; 12 males/10 females; age: 66.6 ± 2.1 years) completing 12 weeks of guided skiing or a control group (CG; n=20; 10 males/10 females; age: 67.3 ± 4.4 years). CVRF were assessed before and after the intervention period. No cardiovascular event occurred within a total of 795.1 h of skiing. A significant increase in exercise capacity in IG (ΔVO(2 max) : +2.0 mL/kg/min, P=0.005) but not in CG (ΔVO(2 max) : -0.1 mL/kg/min, P=0.858; IG vs CG: P=0.008) as well as a decrease in body fat mass [IG: -2.3%, P<0.0001; CG: ± 0.0%, P=0.866; IG vs CG: P<0.0001] was achieved. Blood pressure, blood lipids, heart rate and everyday physical activity remained essentially unchanged. Alpine skiing in the elderly is safe with respect to cardiovascular events, and improves some, but not all CVRF.

The effectiveness of exercise interventions for the management of frailty: a systematic review

This systematic review examines the effectiveness of current exercise interventions for the management of frailty. Eight electronic databases were searched for randomized controlled trials that identified their participants as “frail” either in the title, abstract, and/or text and included exercise as an independent component of the intervention. Three of the 47 included studies utilized a validated definition of frailty to categorize participants. Emerging evidence suggests that exercise has a positive impact on some physical determinants and on all functional ability outcomes reported in this systematic review. Exercise programs that optimize the health of frail older adults seem to be different from those recommended for healthy older adults. There was a paucity of evidence to characterize the most beneficial exercise program for this population. However, multicomponent training interventions, of long duration (≥5 months), performed three times per week, for 30–45 minutes per session, generally had superior outcomes than other exercise programs. In conclusion, structured exercise training seems to have a positive impact on frail older adults and may be used for the management of frailty.

Exercise as an intervention for frailty

By 2015, nearly 15% of the US population will be older than 65 years. In 2030, there will be more than 70 million older Americans. This increase in the elderly population has prompted interest in recent years toward the study of frail older adults. This article reviews the literature investigating the utility of aerobic and resistance exercise training as an intervention for frailty in older adults. In addition, areas of future research are addressed, including concerns related to the dissemination of exercise interventions on a widespread scale. Guidelines for an "exercise prescription" for frail older adults are briefly outlined.

Mitochondrial function as a determinant of life span

Average human life expectancy has progressively increased over many decades largely due to improvements in nutrition, vaccination, antimicrobial agents, and effective treatment/prevention of cardiovascular disease, cancer, etc. Maximal life span, in contrast, has changed very little. Caloric restriction (CR) increases maximal life span in many species, in concert with improvements in mitochondrial function. These effects have yet to be demonstrated in humans, and the duration and level of CR required to extend life span in animals is not realistic in humans. Physical activity (voluntary exercise) continues to hold much promise for increasing healthy life expectancy in humans, but remains to show any impact to increase maximal life span. However, longevity in Caenorhabditis elegans is related to activity levels, possibly through maintenance of mitochondrial function throughout the life span. In humans, we reported a progressive decline in muscle mitochondrial DNA abundance and protein synthesis with age. Other investigators also noted age-related declines in muscle mitochondrial function, which are related to peak oxygen uptake. Long-term aerobic exercise largely prevented age-related declines in mitochondrial DNA abundance and function in humans and may increase spontaneous activity levels in mice. Notwithstanding, the impact of aerobic exercise and activity levels on maximal life span is uncertain. It is proposed that age-related declines in mitochondrial content and function not only affect physical function, but also play a major role in regulation of life span. Regular aerobic exercise and prevention of adiposity by healthy diet may increase healthy life expectancy and prolong life span through beneficial effects at the level of the mitochondrion.

Exercise and health in frail elderly people: a review of randomized controlled trials

Frailty is a physiological syndrome that increases the risk of poor health. Although some research has been conducted to study the benefits of physical exercise in frail elderly populations, different operational definitions of frailty have been used, and this makes the studies difficult to compare. The present review was aimed at examining the influence of exercise on health in frail older adults. Studies using randomized controlled trials that administered an exercise program to a frail elderly population and that had an operational definition of frailty were selected from publications between January 2000 and October 2008. Information about the study population, frailty criteria, exercise program, principles of exercise training, randomization procedures, main and secondary outcome measures, study follow-up, and control group characteristics was taken from these studies, and the results from a final sample of 28 articles are discussed. Exercise training seems to be a safe and effective tool for promoting and maintaining optimal health levels in a wide variety of vulnerable older adults. However, the lack of studies on a well-defined frail older adult sample with selection procedures based on current knowledge in this field does not allow us, at the present time, to conclude that exercise influences health in this population. Further research is needed to confirm the benefits of exercise on health in frail older adults. The study population must be selected based on current knowledge in the area of frailty, and the design of the exercise program must be based on principles of training.

Transcriptional and post-transcriptional regulation of mitochondrial biogenesis in skeletal muscle: effects of exercise and aging

Acute contractile activity of skeletal muscle initiates the activation of signaling kinases. This promotes the phosphorylation of transcription factors, leading to enhanced DNA binding and transcriptional activation and/or repression. The mRNA products of nuclear genes encoding mitochondrial proteins are translated in the cytosol and imported into pre-existing mitochondria. When contractile activity is repeated, the recapitulation of these cellular events progressively leads to an expansion of the mitochondrial reticulum within muscle. This has physiologically relevant health benefit, including enhanced lipid metabolism and reduced muscle fatigability. In aging skeletal muscle, the response to contractile activity appears to be attenuated, suggesting that a greater contractile stimulus is required to attain a similar phenotype adaptation. This review summarizes our current understanding of the effects of exercise on the gene expression pathway leading to organelle biogenesis in muscle.

Exercise training from late middle age until senescence does not attenuate the declines in skeletal muscle aerobic function

We previously showed that 7 wk of treadmill exercise training in late-middle-aged rats can reverse the modest reductions in skeletal muscle aerobic function and enzyme activity relative to values in young adult rats (Exp Physiol 93: 863-871, 2008). The purpose of the present study was to determine whether extending this training program into senescence would attenuate the accelerated decline in the muscle aerobic machinery normally seen at this advanced age. For this purpose, 29-mo-old Fisher 344 Brown-Norway rats underwent 5 or 7 mo of treadmill exercise training. Training resulted in greater exercise capacity during an incremental treadmill exercise test and reduced percent body fat in 34- and 36-mo-old rats and improved survival. Despite these benefits at the whole body level, in situ muscle aerobic capacity and muscle mass were not greater in the trained groups at 34 mo or 36 mo of age. Similarly, the trained groups did not have higher activities of citrate synthase (CS) or Complex IV in homogenates of either the plantaris (fast twitch) or the soleus (slow twitch) muscles at either age. Finally, protein expression of CS (a marker of mitochondrial content) and peroxisome proliferator-activated receptor-gamma coactivator-1 (relating to the drive on mitochondrial biogenesis) were not higher in the trained groups. Therefore, although treadmill training from late middle age into senescence had significant benefits on running capacity, survival, and body fat, it did not prevent the declines in muscle mass, muscle aerobic capacity, or mitochondrial enzyme activities normally seen across this age, revealing a markedly diminished plasticity of the aerobic machinery in response to endurance exercise at advanced age.

[Aging and physical activity data on which to base recommendations for exercise in older adults]

An abundance of epidemiological research confirms the benefits of physical activity in reducing risk of various age-related morbidities and all-cause mortality. Analysis of the literature focusing on key exercise variables (e.g., intensity, type, and volume) suggests that the requisite beneficial amount of activity is that which engenders improved cardiorespiratory fitness, strength, power, and, indirectly, balance. Age-related declines in these components are such that physical limitations impinge on functional activities of daily living. However, an exercise programme can minimize declines, thus preventing older adults (age 65+ years) from crossing functional thresholds of inability. Cross-sectional and longitudinal data demonstrate that cardiorespiratory fitness is associated with functional capacity and independence; strength and, importantly, power are related to performance and activities of daily living; and balance-mobility in combination with power are important factors in preventing falls. Exercise interventions have documented that older adults can adapt physiologically to exercise training, with gains in functional capacities. The few studies that have explored minimal or optimal activity requirements suggest that a threshold (intensity) within the moderately vigorous domain is needed to achieve and preserve related health benefits. Thus, physical activity and (or) exercise prescriptions should emphasize activities of the specificity and type to improve components related to the maintenance of functional capacity and independence; these will also delay morbidity and mortality. An appropriate recommendation for older adults includes moderately vigorous cardiorespiratory activities (e.g., brisk walking), strength and (or) power training for maintenance of muscle mass and specific muscle-group performance, as well as "balance-mobility practice" and flexibility (stretching) exercise as needed.