Grip strength changes over 27 yr in Japanese-American men

Estrogen influences on neuromuscular function in postmenopausal women

Exposure to ovarian sex steroids during different life phases has long-term effects on women's health and wellbeing. Menopause is characterized by rapid decline in ovarian sex steroids already during mid-life, between the ages of 46 and 52. Due to the menopause-related hormonal changes, women in most western countries live more than one-third of their lives in postmenopausal status. The role of ovarian steroids on neuromuscular function in middle-aged and older women has been investigated since the 1980s with increasing volume of research during the last decades. This review considers how different components of the neuromuscular system may be influenced by estrogens and so affects neuromuscular function in postmenopausal women. The main focus is on muscle strength and power, which are closely associated with mobility and functional capacity among older populations. In the end of the review, we summarize recent findings on the underlying biological mechanisms in skeletal muscle that could explain the association between hormone replacement therapy and neuromuscular function among postmenopausal women.

Acceleration training for improving physical fitness and weight loss in obese women

BACKGROUND

Reducing body weight and visceral adipose tissue (VAT) are the primary goals for maintaining health in obese individuals as compared to those of normal weight, but it is also important to maintain physical fitness for a healthy life after weight-loss. Acceleration training (AT) has recently been indicated as an alternative to resistance training for elite athletes and also as a component of preventive medicine. However, it is unclear whether combining AT with a weight-loss diet will improve physical fitness in obese individuals. The present study aimed to determine the synergistic effects of AT on body composition and physical fitness with weight-loss program in overweight and obese women.

METHODS

Twenty-eight obese, middle-aged women were divided into two groups as follows: diet and aerobic exercise group (DA; BMI: 29.3 ± 3.0 kg/m2); and diet, aerobic exercise and acceleration training group (DAA; BMI: 31.2 ± 4.0 kg/m2). Both groups included a 12-week weight-loss program. Body composition, visceral adipose tissue (VAT) area and physical fitness (hand grip, side-to-side steps, single-leg balance with eyes closed, sit-and-reach and maximal oxygen uptake) were measured before and after the program.

RESULT

Body weight, BMI, waist circumference and VAT area decreased significantly in both groups. Hand grip (2.1 ± 3.0 kg), single-leg balance (11.0 ± 15.4 s) and sit-and-reach (6.5 ± 4.8 cm) improved significantly only in the DAA group.

CONCLUSIONS

Our findings indicate that combining AT with classical lifestyle modifications is effective at reducing VAT, and it may enhance muscle strength and performance in overweight and obese women.

Age and grip strength predict hand dexterity in adults

In the scientific literature, there is much evidence of a relationship between age and dexterity, where increased age is related to slower, less nimble and less smooth, less coordinated and less controlled performances. While some suggest that the relationship is a direct consequence of reduced muscle strength associated to increased age, there is a lack of research that has systematically investigated the relationships between age, strength and hand dexterity. Therefore, the aim of this study was to examine the associations between age, grip strength and dexterity. 107 adults (range 18-93 years) completed a series of hand dexterity tasks (i.e. steadiness, line tracking, aiming, and tapping) and a test of maximal grip strength. We performed three phases of analyses. Firstly, we evaluated the simple relationships between pairs of variables; replicating the existing literature; and found significant relationships of increased age and reduced strength; increased age and reduced dexterity, and; reduced strength and reduced dexterity. Secondly, we used standard Multiple Regression (MR) models to determine which of the age and strength factors accounted for the greater variance in dexterity. The results showed that both age and strength made significant contributions to the data variance, but that age explained more of the variance in steadiness and line tracking dexterity, whereas strength explained more of the variance in aiming and tapping dexterity. In a third phase of analysis, we used MR analyses to show an interaction between age and strength on steadiness hand dexterity. Simple Slopes post-hoc analyses showed that the interaction was explained by the middle to older aged adults showing a relationship between reduced strength and reduced hand steadiness, whereas younger aged adults showed no relationship between strength and steadiness hand dexterity. The results are discussed in terms of how age and grip strength predict different types of hand dexterity in adults.

Comparison of quadriceps strength and handgrip strength in their association with health outcomes in older adults in primary care

Sarcopenia is thought to play a major role in the functional impairment that occurs with old age. In clinical practice, sarcopenia is often determined by measuring handgrip strength. Here, we compared the lower limb quadriceps strength to the handgrip strength in their association with health outcomes in older adults in primary care. Our study population consisted of older adults (n = 764, 68.2% women, median age 83) that participated in the Integrated Systemic Care for Older People (ISCOPE) study. Participants were visited at baseline to measure quadriceps strength and handgrip strength. Data on health outcomes were obtained at baseline and after 12 months (including life satisfaction, disability in daily living, GP contact-time and hospitalization). Quadriceps strength and handgrip strength showed a weak association (β = 0.42 [95% CI 0.33-0.50]; R (2) = 0.17). Quadriceps strength and handgrip strength were independently associated with health outcomes at baseline, including quality of life, disability in daily living, GP contact-time, hospitalization, and gait speed. Combined weakness of the quadriceps and handgrip distinguished a most vulnerable subpopulation that presented with the poorest health outcomes. At follow-up, handgrip strength showed an association with quality of life (β = 0.05; P = 0.002) and disability in daily living (β = -0.5; P = 0.004). Quadriceps weakness did not further contribute to the prediction of the measured health outcomes. We conclude that quadriceps strength is only moderately associated with handgrip strength in an older population and that the combination of quadriceps strength and handgrip strength measurements may aid in the identification of older adults in primary care with the poorest health outcomes. In the prediction of poor health outcomes, quadriceps strength measurements do not show an added value to the handgrip strength.

Human centred design considerations for connected health devices for the older adult

Connected health devices are generally designed for unsupervised use, by non-healthcare professionals, facilitating independent control of the individuals own healthcare. Older adults are major users of such devices and are a population significantly increasing in size. This group presents challenges due to the wide spectrum of capabilities and attitudes towards technology. The fit between capabilities of the user and demands of the device can be optimised in a process called Human Centred Design. Here we review examples of some connected health devices chosen by random selection, assess older adult known capabilities and attitudes and finally make analytical recommendations for design approaches and design specifications.

A life-course approach to healthy ageing: maintaining physical capability

Research on healthy ageing lacks an agreed conceptual framework and has not adequately taken into account the growing evidence that social and biological factors from early life onwards affect later health. We conceptualise healthy ageing within a life-course framework, separating healthy biological ageing (in terms of optimal physical and cognitive functioning, delaying the onset of chronic diseases, and extending length of life for as long as possible) from changes in psychological and social wellbeing. We summarise the findings of a review of healthy ageing indicators, focusing on objective measures of physical capability, such as tests of grip strength, walking speed, chair rises and standing balance, which aim to capture physical functioning at the individual level, assessing the capacity to undertake the physical tasks of daily living. There is robust evidence that higher scores on these measures are associated with lower rates of mortality, and more limited evidence of lower risk of morbidity, and of age-related patterns of change. Drawing on a research collaboration of UK cohort studies, we summarise what is known about the influences on physical capability in terms of lifetime socioeconomic position, body size and lifestyle, and underlying physiology and genetics; the evidence to date supports a broad set of factors already identified as risk factors for chronic diseases. We identify a need for larger longitudinal studies to investigate age-related change and ethnic diversity in these objective measures, the dynamic relationships between them, and how they relate to other component measures of healthy ageing. Robust evidence across cohort studies, using standardised measures within a clear conceptual framework, will benefit policy and practice to promote healthy ageing.

Comparison of explosive force between young and elderly women: evidence of an earlier decline from explosive force

The aging process causes many changes in muscle strength, and analysis of explosive force from handgrip strength seems to be useful and promising in studying the aging musculoskeletal system. Therefore, the purpose of this study was to investigate if explosive force parameters [rate of force development (RFD) and contractile impulse (CI) over the time interval of 0-200 ms from the onset of contraction] during handgrip efforts decline differently than maximum handgrip strength with increasing age. Twenty healthy young women (20-27 years) and 65 healthy elderly women, assigned into three age groups (50-64, 65-74, and 75-86 years), participated in this study. All participants performed two maximal grip attempts. Handgrip data were recorded as force-time curves, peak force, and explosive force parameters. Our results revealed that peak force decreased significantly (p < 0.05) for those who are 65 years old, while explosive force parameters decreased significantly (p < 0.05) for those aged 50 years. These data indicate that the decline in explosive grip force-generating capacity may begin earlier (i.e., for those aged 50 years old) than peak force during the aging process. Our findings suggest that the aging process reduces the explosive grip force-generating capacity before affecting peak force.

Hand impairment and activity limitations in four chronic diseases

STUDY DESIGN

Retrospective cohort.

INTRODUCTION

Hand involvement in osteoarthritis (OA) and rheumatoid arthritis (RA) are well known to occupational and physical therapists; however, it is not known whether the impairments and activity limitations with diabetes (DMII) and systemic sclerosis (SSc) are as severe as those observed with OA and RA.

PURPOSE

To compare the hand impairments and activity limitations in the 4 diseases.

METHODS

A convenience sample of 156 participants received evaluations of hand impairments: strength, joint motion, and dexterity and completed a hand activity limitations questionnaire.

RESULTS

The SSc and RA participants had weaker pinch, decreased joint motion and more activity limitations than the DMII and OA groups. There were no significant differences between the groups for right hand grip strength and pegboard dexterity, and applied dexterity.

CONCLUSIONS

OA and DMII groups had significantly less impairments and activity limitations than the SSc and RA groups.

LEVEL OF EVIDENCE

2C.

Midlife and late-life handgrip strength and risk of cause-specific death in a general Japanese population: the Hisayama Study

BACKGROUND

Decreased handgrip strength has been reported to be a risk factor for all-cause death among the elderly. However, it is unclear whether handgrip strength measured in midlife is associated with risk of all-cause and cause-specific death in the general population.

METHODS

We followed, prospectively, a total of 2527 community-dwelling Japanese (1064 men and 1463 women) aged ≥40 years for 19 years. Participants were divided into three groups according to the age-specific and sex-specific tertiles of handgrip strength (T1, lowest; T3, highest).

RESULTS

During the follow-up period, 783 participants died, of whom 235 died of cardiovascular disease, 249 of cancer, 154 of respiratory disease and 145 of other causes. In the middle-aged group (40-64 years), multivariable-adjusted HRs (95% CIs) for all-cause death were 0.75 (0.56 to 0.99) in T2 and 0.49 (0.35 to 0.68) in T3 compared with T1 as a reference. Corresponding HRs (95% CI) in the elderly group (≥65 years) were 0.50 (0.40 to 0.62) and 0.41 (0.32 to 0.51), respectively. As regards the cause of death, higher levels of handgrip strength were significantly associated with decreased risks of cardiovascular death, respiratory death and death from other causes, but not of cancer, in the middle-aged and the elderly.

CONCLUSIONS

Our findings suggest that handgrip strength levels in midlife and late life are inversely associated with the risks of all-cause and non-cancer death in the general Japanese population.

Grip strength and its determinants among older people in different healthcare settings

BACKGROUND

low muscle strength is central to geriatric syndromes including sarcopenia and frailty. It is well described in community-dwelling older people, but the epidemiology of grip strength of older people in rehabilitation or long-term care has been little explored.

OBJECTIVE

to describe grip strength of older people in rehabilitation and nursing home settings.

DESIGN

cross-sectional epidemiological study.

SETTING

three healthcare settings in one town.

SUBJECTS

hundred and one inpatients on a rehabilitation ward, 47 community rehabilitation referrals and 100 nursing home residents.

METHODS

grip strength, age, height, weight, body mass index, number of co-morbidities and medications, Barthel score, Mini-Mental State Examination (MMSE), nutritional status and number of falls in the last year were recorded.

RESULTS

grip strength differed substantially between healthcare settings for both men and women (P < 0.0001). Nursing home residents had the lowest age-adjusted mean grip strength and community rehabilitation referrals the highest. Broadly higher grip strength was associated in univariate analyses with younger age, greater height and weight, fewer comorbidities, higher Barthel score, higher MMSE score, better nutritional status and fewer falls. However, after mutual adjustment for these factors, the difference in grip strength between settings remained significant. The Barthel score was the characteristic most strongly associated with grip strength.

CONCLUSIONS

older people in rehabilitation and care home settings had lower grip strength than reported for those living at home. Furthermore grip strength varied widely between healthcare settings independent of known major influences. Further research is required to ascertain whether grip strength may help identify people at risk of adverse health outcomes within these settings.

Prestroke weight loss is associated with poststroke mortality among men in the Honolulu-Asia Aging Study

OBJECTIVE

To examine baseline prestroke weight loss and poststroke mortality among men.

DESIGN

Longitudinal study of late-life prestroke body mass index (BMI), weight loss, and BMI change (midlife to late life) with up to 8-year incident stroke and mortality follow-up.

SETTING

Community-based aging study data.

PARTICIPANTS

Japanese-American men (N=3581; age range, 71-93y) who were stroke free at baseline.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

Poststroke mortality: 30 days poststroke, analyzed with stepwise multivariable logistic regression; and long-term poststroke (up to 8y), analyzed with stepwise multivariable Cox regression.

RESULTS

Weight loss (4.5kg decrements) was associated with increased 30-day poststroke mortality (adjusted odds ratio=1.48; 95% confidence interval [CI], 1.14-1.92), long-term mortality after incident stroke (all types, n=225; adjusted hazards ratio (aHR)=1.25; 95% CI, 1.09-1.44), and long-term mortality after incident thromboembolic stroke (n=153; aHR=1.19; 95% CI, 1.01 to 1.40). Men with overweight/obese late-life BMI (≥25kg/m(2), compared with healthy/underweight BMI) had increased long-term mortality after incident hemorrhagic stroke (n=54; aHR=2.27; 95% CI, 1.07-4.82). Neither desirable nor excessive BMI reductions (vs no change/increased BMI) were associated with poststroke mortality. In the overall sample (N=3581), nutrition factors associated with increased long-term mortality included the following: (1) weight loss (10lb decrements; aHR=1.15; 95% CI, 1.09-1.21), (2) underweight BMI (vs healthy BMI; aHR=1.76; 95% CI, 1.40-2.20), and (3) both desirable and excessive BMI reductions (vs no change or gain, separate model from weight loss and BMI; aHR range, 1.36-1.97; P<.001).

CONCLUSIONS

Although obesity is a risk factor for stroke incidence, prestroke weight loss was associated with increased poststroke (all types and thromboembolic) mortality. Overweight/obese late-life BMI was associated with increased posthemorrhagic stroke mortality. Desirable and excessive BMI reductions were not associated with poststroke mortality. Weight loss, underweight late-life BMI, and any BMI reduction were all associated with increased long-term mortality in the overall sample.

Indoor mobility-related fatigue and muscle strength in nonagenarians: a prospective longitudinal study

BACKGROUND AND AIMS

Mobility-related fatigue is an important indicator of functional decline in old age, however, very little is known about fatigue in the oldest old population segment. The aim of this study was to examine the association between indoor mobility-related fatigue and muscle strength decline in nonagenarians.

METHODS

The study is based on a prospective longitudinal study of all Danes born in 1905 and assessed in 1998, 2000 and 2003, and includes 92- to 93-year-old persons who were independent of help in basic indoor mobility at baseline (n = 1,353). Fatigue was assessed at baseline and defined as a subjective feeling of fatigue when transferring or walking indoors. The outcome measure, maximum grip strength, was measured at each measurement point.

RESULTS

Grip strength declined throughout the study in participants with and without fatigue, but those reporting fatigue had significantly (P < .001) lower muscle strength during the entire study period. Longitudinal analyses indicated slightly slower decline in muscle strength among participants with fatigue compared to those without; however, observed selective dropout of participants with fatigue and poor performance at baseline needs to be considered when interpreting the results. Accordingly, participants without fatigue had significantly higher chances of being alive and having muscle strength above gender-specific median at first (RR 1.32, 95 % CI 1.07-1.58), second (RR 1.51, 1.06-1.96) and third (RR 1.39, 1.01-1.97) measurement points.

CONCLUSIONS

Indoor mobility-related fatigue in advanced later life should not merely be considered as an unpleasant symptom, but rather an indicator of physical impairment, and consequently declined physiological reserve.

Hand grip strength and associated factors in non-institutionalised men and women 50 years and older in South Africa

BACKGROUND

Little is known about the prevalence, predictors and gender differences in hand grip strength of older adults in Africa. This study aims to investigate social and health differences in hand grip strength among older adults in a national probability sample of older South Africans who participated in the Study of Global Ageing and Adults Health (SAGE wave 1) in 2008.

METHODS

We conducted a national population-based cross-sectional study with a sample of 3840 men and women aged 50 years or older in South Africa. The questionnaire included socio-demographic characteristics, health variables, and anthropometric measurements. Linear multivariate regression analysis was performed to assess the association of social factors, health variables and grip strength.

RESULTS

The mean overall hand grip strength was 37.9 kgs for men (mean age 61.1 years, SD = 9.1) and 31.5 kgs for women (mean age 62.0 years, SD = 9.7). In multivariate analysis among men, greater height, not being underweight and lower functional disability was associated with greater grip strength, and among women, greater height, better cognitive functioning, and lower functional disability were associated with greater grip strength.

CONCLUSIONS

Greater height and lower functional disability were found for both older South African men and women to be significantly associated with grip strength.

Longitudinal impact of aging on muscle quality in middle-aged men

The present follow-up study aims at assessing the longitudinal changes in muscle quality after an interval of 9.45 years in middle-aged men. In addition, the relative contribution of muscle mass, muscle strength, and muscle power at middle age to these changes was investigated. The results showed a small, though unexpected, increase in total body and leg muscle mass (respectively 0.22 ± 0.04 and 0.29 ± 0.06 % yearly, p < 0.0001), whereas basic strength (-0.71 to -0.87 % yearly, p < 0.0001) and velocity-dependent strength and power (-1.19 to -1.86 % yearly, p < 0.0001) declined. Consequently, muscle quality, defined as the ratio of basic strength or velocity-dependent strength and power to muscle mass decreased (-1.46 to -2.43 % yearly, p < 0.0001) from baseline to follow-up. We found that baseline basic strength is a strong determinant of the decline in muscle quality basic strength with advancing age, whereas only a small part of the age-associated decline in muscle quality based on velocity-dependent strength and power could be explained. To conclude, our results indicate that muscle becomes less efficient at middle age and that baseline muscle strength is a strong predictor of this change. These findings imply that unmeasured neural factors, influencing both contraction speed and the capacity of muscle to produce strength, are possibly other involved determinants. Therefore, timely interventions including strength training and higher-velocity strength training at middle age are recommended.

Handgrip strength predicts persistent walking recovery after hip fracture surgery

BACKGROUND

In older people, hip fractures often lead to disability and death. We evaluated handgrip strength, an objective measure of physical function for bedridden patients, as a predictor of walking recovery in the year after fracture surgery.

METHODS

This multicenter prospective cohort study included 504 patients, aged 70 years or more, who were admitted to the hospital for hip fracture surgery and were formerly able to walk independently. A multidimensional geriatric evaluation that included a physical examination, Short Portable Mental Status Questionnaire, Geriatric Depression Scale, Charlson Index, Basic Activities of Daily Living, and grip strength was administered at the time of admission. Follow-ups were performed every 3 months for 1 year after surgery to assess functional status and survival. The walking recovery probability was evaluated using multivariable logistic regression models.

RESULTS

The mean age of the participants was 85.3 ± 5.5 years, and 76.1% of the participants were women. The mean grip strength was greater in men (β: 6.6 ± 0.62, P < .001) and was directly related to the Short Portable Mental Status Questionnaire results (P < .001), Basic Activities of Daily Living results (P < .001), serum vitamin D levels (P = .03), and time before surgery (P < .001), whereas it was inversely related to age (P < .001), Geriatric Depression Scale score (P < .001), and Charlson Index (P < .001). After adjusting for confounders, the grip strength was directly associated with the probability of both incident and persistent walking recovery (odds ratio highest tertile vs lowest tertile, 2.84, confidence interval, 1.76-4.59 and 2.79, confidence interval, 1.35-5.79, respectively).

CONCLUSIONS

In older patients with hip fractures, early grip strength evaluation might provide important prognostic information regarding the patient's future functional trajectory.

Digit ratio (2D:4D) and handgrip strength in Hani ethnicity

Introduction

The ratio of the length of the second finger to the fourth finger (2D:4D) in humans is considered as a putative marker of prenatal exposure to testosterone, and has been progressively adopted as one useful tool to evaluate the effect of prenatal hormones in some traits such as physical ability. Handgrip strength is one authentic measure of physical ability and is generally used on the anthropological research within an evolutionary viewpoint.

Methods

Here we present the first evidence on 2D:4D and handgrip strength on adult participants of Hani ethnicity and explore the relationship between digit ratio (2D:4D) and handgrip strength. We examined 2D:4D and handgrip strength of 80 males and 60 females at Bubeng village, in the Yunnan province of China.

Results

The mean 2D:4D in females was higher than that in males for each hand. Females showed significantly higher 2D:4D than males in the right hand rather than in the left hand. Males displayed significantly higher handgrip strength than females for both hands. Handgrip strength decreased with age for both sexes. A significant negative correlation between 2D:4D and handgrip strength was found in the right hand of males.

Conclusion

The relationship between 2D:4D and handgrip strength may be attributed to evolutionary drive of sexual selection operating on fetal programming.

Grip strength measurement in older adults in Taiwan: a comparison of three testing positions

AIM

The purpose of this study was to explore the effects of three commonly used positions on grip strength measurement in older people.

METHOD

A total of 249 (113 women, 136 men) older participants, 72.8 ± 6.5 years old, participated in this study. Grip strength (kg) was measured in three positions: (i) the standard posture (sitting, elbow flexed 90°) suggested by the American Society of Hand Therapists; (ii) standing, elbow flexed 90°; and (3) standing, elbow fully extended.

RESULTS

One-way repeated measures analysis of variance showed that grip strength was significantly greater in the standing position with the elbow fully extended than in the other two positions.

CONCLUSIONS

The grip strengths obtained from the three positions were not all comparable in our community-dwelling older adults. Clinicians and researchers need to be cautious when choosing testing position for assessing and interpreting grip strength results obtained from these positions.

A cross-sectional assessment of oxidative DNA damage and muscle strength among elderly people living in the community

OBJECTIVES

The mechanism by which muscle weakness leads to an increased risk of death remains a subject of interest. In this context, the aim of this study is to assess the relationship between urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and muscle strength, and other risk factors contributing to poor muscle strength in older persons.

METHODS

This was a cross-sectional study in which a total of 86 participants, both men and women, aged 65 years or above were screened for urinary 8-OHdG, and muscle strength as measured by handgrip strength.

RESULTS

Handgrip strength was lower in participants who had history of acute or chronic disease. Urinary 8-OHdG level was negatively associated with muscle strength, and the association remained after adjusting for confounding factors.

CONCLUSIONS

Urinary 8-OHdG is associated with muscle strength. These findings may be clinically relevant as there is a possibility of controlling oxidative DNA damage by healthy behaviors related to lifestyle.

Gender specific age-related changes in bone density, muscle strength and functional performance in the elderly: a-10 year prospective population-based study

BACKGROUND

Age-related losses in bone mineral density (BMD), muscle strength, balance, and gait have been linked to an increased risk of falls, fractures and disability, but few prospective studies have compared the timing, rate and pattern of changes in each of these measures in middle-aged and older men and women. This is important so that targeted strategies can be developed to optimise specific musculoskeletal and functional performance measures in older adults. Thus, the aim of this 10-year prospective study was to: 1) characterize and compare age- and gender-specific changes in BMD, grip strength, balance and gait in adults aged 50 years and over, and 2) compare the relative rates of changes between each of these musculoskeletal and functional parameters with ageing.

METHODS

Men (n = 152) and women (n = 206) aged 50, 60, 70 and 80 years recruited for a population-based study had forearm BMD, grip strength, balance and gait velocity re-assessed after 10-years.

RESULTS

The annual loss in BMD was 0.5-0.7% greater in women compared to men aged 60 years and older (p < 0.05- < 0.001), but there were no gender differences in the rate of loss in grip strength, balance or gait. From the age of 50 years there was a consistent pattern of loss in grip strength, while the greatest deterioration in balance and gait occurred from 60 and 70 years onwards, respectively. Comparison of the changes between the different measures revealed that the annual loss in grip strength in men and women aged <70 years was 1-3% greater than the decline in BMD, balance and gait velocity.

CONCLUSION

There were no gender differences in the timing (age) and rate (magnitude) of decline in grip strength, balance or gait in Swedish adults aged 50 years and older, but forearm BMD decreased at a greater rate in women than in men. Furthermore, there was heterogeneity in the rate of loss between the different musculoskeletal and function parameters, especially prior to the age of 70 years, with grip strength deteriorating at a greater rate than BMD, balance and gait.

Age-related decrease in physical activity and functional fitness among elderly men and women

AIM

To determine differences in physical activity level and functional fitness between young elderly (60-69 years) and old elderly (70-80 years) people with the hypothesis that an age-related decline would be found.

METHODS

A total of 1288 participants' level of physical activity was evaluated using the International Physical Activity Questionnaire: 594 were male (mean ± standard deviation: body height 175.62 ± 9.78 cm; body weight 82.26 ± 31.33 kg) and 694 female (mean ± standard deviation: body height 165.17 ± 23.12 cm; body weight 69.74 ± 12.44 kg). Functional fitness was also estimated using the Senior Fitness Test: back scratch, chair sit and reach, 8-foot up and go, chair stand up for 30 seconds, arm curl, and 2-minute step test.

RESULTS

Significant differences (P < 0.05) were found for all Senior Fitness tests between young elderly (60-69 years) and old elderly (70-80) men. Similar results were found for the women, except no significant differences were found for the chair sit and reach and the 2-minute step test. From the viewpoint of energy consumption estimated by the International Physical Activity Questionnaire, moderate physical activity is dominant. In addition, with aging, among men and women older than 60 years, the value of the Metabolic Equivalent of Task in total physical activity significantly reduces (P < 0.05).

CONCLUSIONS

This study found that the reduction in physical activity level and functional fitness was equal for both men and women and was due to the aging process. These differences between young and old elderly people were due to the reduction of muscle strength in both upper and lower limbs and changes in body-fat percentage, flexibility, agility, and endurance.

[Handgrip strength and flexibility and their association with anthropometric variables in the elderly]

OBJECTIVE

To verify the correlation between handgrip strength (HGS) and flexibility with age and anthropometric variables in the elderly.

METHODS

This was a cross-sectional home-based study of elderly individuals enrolled in the Family Health Strategy of Campina Grande/PB. Gender, age, HGS, flexibility, arm muscle circumference (AMC), corrected arm muscle area (CAMA), and body mass index (BMI) were recorded.

RESULTS

A total of 420 elderly individuals were evaluated. Correlations of HGS with age, AMC and CAMA, in both genders, were observed. BMI correlated with HGS only in females. Flexibility correlated with BMI in males. In the multivariate analysis, age and AMC were predictive variables of the HGS variation in females. In males, age was the only variable predictive of HGS, and BMI was the predictor of flexibility variation.

CONCLUSION

The results indicate a probable influence of age and anthropometric variables in muscular strength, as well as that of excess weight in flexibility limitation.

Physical function measurements predict mortality in ambulatory older men

BACKGROUND

To assess and compare the predictive value of physical function measurements (PFMs) for all-cause mortality in older men and to evaluate the Timed Up and Go test (TUG) as a predictor in subjects with underlying comorbidity.

DESIGN

Observational study of a population-based sample of 352 ambulatory older men aged 71-86 at study baseline. The Rapid disability rating scale-2, 36-Item short form health survey, Grip strength, Five times sit-to-stand test, Standing balance, and TUG were determined at baseline. Associations with all-cause mortality were assessed using Cox proportional hazard analyses. Age, Body mass index (BMI), smoking status, education, physical activity and cognitive status were included as confounders. Follow-up exceeded 15 years. Comorbidity status was categorized into cardiovascular disease, chronic obstructive pulmonary disease (COPD) and diabetes mellitus.

RESULTS

All examined PFMs were associated with all-cause mortality. TUG was the best predictor (adjusted HR per SD increase = 1·58, 95% CI = 1·40-1·79, P < 0·001) for global mortality and continued to be predictive in subjects with cardiovascular disease (adjusted HR per SD increase = 1·80, 95% CI = 1·40-2·33, P < 0·001).

CONCLUSIONS

The assessment of physical functioning is important in the evaluation of older persons. We encourage the use of the TUG as a reliable, quick and feasible screening tool in clinical settings.

Body mass index, muscle strength and physical performance in older adults from eight cohort studies: the HALCyon programme

Objective

To investigate the associations of body mass index (BMI) and grip strength with objective measures of physical performance (chair rise time, walking speed and balance) including an assessment of sex differences and non-linearity.

Methods

Cross-sectional data from eight UK cohort studies (total N = 16 444) participating in the Healthy Ageing across the Life Course (HALCyon) research programme, ranging in age from 50 to 90+ years at the time of physical capability assessment, were used. Regression models were fitted within each study and meta-analysis methods used to pool regression coefficients across studies and to assess the extent of heterogeneity between studies.

Results

Higher BMI was associated with poorer performance on chair rise (N = 10 773), walking speed (N = 9 761) and standing balance (N = 13 921) tests. Higher BMI was associated with stronger grip strength in men only. Stronger grip strength was associated with better performance on all tests with a tendency for the associations to be stronger in women than men; for example, walking speed was higher by 0.43 cm/s (0.14, 0.71) more per kg in women than men. Both BMI and grip strength remained independently related with performance after mutual adjustment, but there was no evidence of effect modification. Both BMI and grip strength exhibited non-linear relations with performance; those in the lowest fifth of grip strength and highest fifth of BMI having particularly poor performance. Findings were similar when waist circumference was examined in place of BMI.

Conclusion

Older men and women with weak muscle strength and high BMI have considerably poorer performance than others and associations were observed even in the youngest cohort (age 53). Although causality cannot be inferred from observational cross-sectional studies, our findings suggest the likely benefit of early assessment and interventions to reduce fat mass and improve muscle strength in the prevention of future functional limitations.

The Relationship between Smoking, Socioeconomic Status and Grip Strength among Community-dwelling Elderly Men in Korea: Hallym Aging Study

OBJECTIVES

Low grip strength is associated with decline in bone mineral density (BMD) and increased risk of spine fracture among the elderly. Smoking, a major factor determining BMD, is also known to have an indirect effect on bone loss. This study investigated whether smoking is associated with grip strength in the community-dwelling elderly in Korea.

METHODS

This study was an outcome of the second of three waves of the Hallym Aging Study from January to May 2007, a population-based study of Koreans aged 45 years and upwards dwelling in Chuncheon. Its 218 subjects comprised men aged 65 years or over. They were evaluated at a general hospital for socioeconomic status, smoking history, and various clinical measures including grip strength.

RESULTS

Grip strength was higher in non-, ex-, and current smokers (33.7 kg, 30.6 kg, and 29.3 kg, respectively). Current smoking was found to increase the risk of decreased grip strength (adjusted odds ratio [aOR], 4.58; 95% confidence interval [CI],1.31 to 16.04) compared with non-smoking, after adjustment for potential covariates including socioeconomic status. After adjustment for smoking effect, education of fewer than six years and monthly income of fewer than 500,000 Korean won increased the risk of decreased grip strength compared with education of more than six years (aOR, 2.88; 95% CI, 1.08 to 7.66) and monthly income of more than 1,500,000 Korean won (aOR, 2.86; 95% CI, 1.08 to 7.54).

CONCLUSIONS

These results showed that current smoking, low education and low income were independent risk factors for decreased grip strength among elderly men in Korea.

Physical performance tests, self-reported outcomes, and accidental falls before and after total knee arthroplasty: an exploratory study

This longitudinal, observational study explored the relationship between physical performance tests, self-reported outcomes, and accidental falling, before and after total knee arthroplasty (TKA). Thirty-seven patients were randomly selected from a larger study of falling before and after surgery conducted at a UK National Health Service Orthopaedic Unit. Physical performance tests were the Berg Balance Score (BBS), Timed Up and Go (TUG), and Hand Grip Strength (HGS). Self-reported outcomes incorporated the Western Ontario and McMaster's Osteoarthritis Index (WOMAC), Activities Balance Confidence Scale (ABC-UK), Geriatric Depression Scale (GDS), and accidental falls. Paired pre- and postoperative data were available on 22 patients. A total of 22.7% patients fell before and after TKA. Postoperative improvement in BBS and TUG was found in 41% and 50% of patients, respectively, HGS did not change. BBS showed a consistent moderate-to-strong association with other physical tests both before and after surgery; TUG (rs -0.76; rs -0.90), maximal HGS (r 0.49; r 0.48), and self-report measures; ABC-UK (r 0.52; r 0.74), WOMAC stiffness (r -0.53; r -0.48), and WOMAC function (r -0.56; r -0.45). Although self-report questionnaires are an efficient, cost-effective approach to outcome assessment in TKA, there is a growing case for inclusion of physical performance tests. The Berg Balance Score may be a useful addition to outcome assessment in patients with TKA.

Performance-based assessments and demand for personal care in older Japanese people: a cross-sectional study

OBJECTIVES

To identify appropriate clinical tests for determining the demand for personal care in older Japanese people.

DESIGN

Cross-sectional observation study.

SETTING

Obu Study of Health Promotion for the Elderly (Obu, Aichi) and Tsukui Ordered Useful Care for Health (241 day-care centres) cohorts in Japan.

PARTICIPANTS

A total of 10 351 individuals aged 65 years or older (6791 with personal care and 3560 without personal care) participated in the study.

MEASURES

Physical performance tests included grip strength, the chair stand test, walking speed at a comfortable pace, and the timed up-and-go test. Personal care was defined as participants who had been certified in the national social long-term care insurance in Japan.

RESULTS

Individuals who received personal care showed a significantly poorer performance than those without personal care for all physical performance tests (p<0.001). Gait speed was the most useful of the physical performance tests to determine the demand for personal care (receiver operating characteristic curve statistics: men, 0.92; women, 0.94; sensitivity: men, 86; women, 90; specificity: men, 85; women, 85). After adjustment for age, sex, cognitive impairment and other physical tests, all physical performance tests were individually associated with the demand for personal care. A slow gait speed (<1 m/s) was more strongly correlated with the demand for personal care than other performance measures (gait speed OR: 5.9; 95% CI: 5.0 to 6.9).

CONCLUSIONS

Clinical tests of physical performance are associated with the demand for personal care in older people. Preventive strategies to maintain physical independence may be required in older adults who show a gait speed slower than 1 m/s. Further research is necessary to confirm these preliminary results.

Age-related differences in Achilles tendon properties and triceps surae muscle architecture in vivo

This study examined the concurrent age-related differences in muscle and tendon structure and properties. Achilles tendon morphology and mechanical properties and triceps surae muscle architecture were measured from 100 subjects [33 young (24 ± 2 yr) and 67 old (75 ± 3 yr)]. Motion analysis-assisted ultrasonography was used to determine tendon stiffness, Young's modulus, and hysteresis during isometric ramp contractions. Ultrasonography was used to measure muscle architectural features and size and tendon cross-sectional area. Older participants had 17% lower (P < 0.01) Achilles tendon stiffness and 32% lower (P < 0.001) Young's modulus than young participants. Tendon cross-sectional area was also 16% larger (P < 0.001) in older participants. Triceps surae muscle size was smaller (P < 0.05) and gastrocnemius medialis muscle fascicle length shorter (P < 0.05) in old compared with young. Maximal plantarflexion force was associated with tendon stiffness and Young's modulus (r = 0.580, P < 0.001 and r = 0.561, P < 0.001, respectively). Comparison between old and young subjects with similar strengths did not reveal a difference in tendon stiffness. The results suggest that regardless of age, Achilles tendon mechanical properties adapt to match the level of muscle performance. Old people may compensate for lower tendon material properties by increasing tendon cross-sectional area. Lower tendon stiffness in older subjects might be beneficial for movement economy in low-intensity locomotion and thus optimized for their daily activities.

Social engagement, health, and changes in occupational status: analysis of the Korean Longitudinal Study of Ageing (KLoSA)

Background

We focused on whether changes in the occupational status of older male adults can be influenced by social engagement and health status measured at the baseline.

Methods

This study used a sample of the Korean Longitudinal Study of Aging (KLoSA), and the study population was restricted to 1.531 men who were aged 55 to 80 years at the 2006 baseline survey and participated in the second survey in 2008. Social engagement and health status, measured by the number of chronic diseases, grip strength, and depressive symptoms as well as covariates (age, marital status, educational level, and household income) were based on data from the 2006 baseline survey. Occupational engagement over the first and second survey was divided into four categories: ‘consistently employed’ (n = 892), ‘employed-unemployed’ (n = 152), ‘unemployed-employed’ (n = 138), and ‘consistently unemployed’ (n = 349).

Results

In the multinomial model, the ‘consistently employed’ and ‘unemployed-employed’ groups had significantly higher social engagement (1.19 and 1.32 times, respectively) than the referent. The number of chronic diseases was significantly associated with four occupational changes, and the ‘unemployed-employed’ had the fewest chronic conditions.

Conclusion

Our finding suggests that social engagement and health status are likely to affect opportunities to continue working or to start working for older male adults.

Is grip strength associated with length of stay in hospitalised older patients admitted for rehabilitation? Findings from the Southampton grip strength study

BACKGROUND

identification of patients at risk of prolonged hospital stay allows staff to target interventions, provide informed prognosis and manage healthcare resources. Admission grip strength is associated with discharge outcomes in acute hospital settings.

OBJECTIVE

to explore the relationship between grip strength and length of stay in older rehabilitation in-patients.

DESIGN

single-centre prospective cohort study.

SETTING

community hospital rehabilitation ward.

SUBJECTS

one hundred and ten patients aged 70 years and over.

METHODS

data on age, height, weight, body mass index (BMI), co-morbidities, medication, residence, grip strength, physical function, cognitive function, frailty, falls, discharge destination and length of stay were recorded.

RESULTS

higher grip strength was associated with reduced length of stay, characterised by an increased likelihood of discharge to usual residence among male rehabilitation in-patients (hazard ratio 1.09 (95% confidence interval 1.01, 1.17) per kilo increase in grip strength, P = 0.02) after adjustment for age and size.

CONCLUSIONS

this is the first prospective study to show that stronger grip strength, particularly among male in-patients, is associated with a shorter length of stay in a rehabilitation ward. This is important because it demonstrates that grip strength can be discriminatory among frailer people. Further research into the clinical applications of grip strength measurement in rehabilitation settings is needed.

Serum albumin in relation to change in muscle mass, muscle strength, and muscle power in older men

OBJECTIVES

To investigate the relationship between serum albumin and change in muscle mass, grip strength, and leg power.

DESIGN

Prospective cohort.

SETTING

Six U.S. academic medical centers.

PARTICIPANTS

Community-dwelling men aged 65 and older participating in the Osteoporotic Fractures in Men (MrOS) Study.

MEASUREMENTS

Serum albumin was measured at baseline in 5,534 participants. Baseline serum albumin was examined in relation to change in appendicular skeletal muscle (ASM) mass, grip strength, and leg power after 2 and 4.6 years. Two-year change in serum albumin was examined with respect to simultaneous change in these outcomes in 1,267 participants.

RESULTS

Baseline serum albumin <40 g/L was not associated with 2- or 4.6-year change in ASM mass, grip strength, or leg power before or after adjustment for confounders. There was no association between serum albumin change and change in grip strength. A statistically significant trend was observed between serum albumin change and change in ASM mass, but there was substantial overlap across confidence intervals (CIs). Participants with a marked decrease (>3 g/L) and mild decrease (1-2 g/L) in serum albumin over 2 years exhibited a modest change of -8.9 W (95% CI = -25.6 to -7.8 W) and -6.3 W (95% CI = -21.2 to -8.5 W) of leg power, respectively (P for trend = .02), compared with those with no decrease in albumin concentration.

CONCLUSION

Serum albumin demonstrated modest and inconsistent trends with loss of muscle mass and function. Low serum albumin within the normal range is not a risk factor for this process in elderly men.

Digit ratio (2D:4D) and handgrip strength in subjects of Han ethnicity: impact of sex and age

The ratio of the length of the second finger to the fourth finger (2D:4D) is considered to be a putative proxy of prenatal exposure to testosterone, and has been increasingly used as a promising tool to evaluate the impact of prenatal androgenization in humans in such traits as physical performance. In this study, for the first time, we present 2D:4D data on adult participants of Han ethnicity. We consider the sexual dimorphism of 2D:4D and handgrip strength, and also report the relationship between 2D:4D and handgrip strength of males and females. The sample consisted of 54 males and 55 females recruited from a remote village in the Qinling Mountains, China. We found sexual dimorphism of both 2D:4D and handgrip strength, i.e., males had lower 2D:4D and right-left 2D:4D than females and greater handgrip strength than females. There was a sex-specific correlation between 2D:4D and handgrip strength, i.e., 2D:4D in the right hand was negatively correlated with handgrip strength in males but not in females. This relationship may be driven by sexual selection operating on fetal programming.

Voice and handgrip strength predict reproductive success in a group of indigenous African females

Evolutionary accounts of human traits are often based on proxies for genetic fitness (e.g., number of sex partners, facial attractiveness). Instead of using proxies, actual differences in reproductive success is a more direct measure of darwinian fitness. Certain voice acoustics such as fundamental frequency and measures of health such as handgrip strength correlate with proxies of fitness, yet there are few studies showing the relation of these traits to reproduction. Here, we explore whether the fundamental frequency of the voice and handgrip strength account for differences in actual reproduction among a population of natural fertility humans. Our results show that both fundamental frequency and handgrip strength predict several measures of reproductive success among a group of indigenous Namibian females, particularly amongst the elderly, with weight also predicting reproductive outcomes among males. These findings demonstrate that both hormonally regulated and phenotypic quality markers can be used as measures of darwinian fitness among humans living under conditions that resemble the evolutionary environment of Homo sapiens. We also argue that these findings provide support for the Grandmother Hypothesis.

Disability in older people with diabetes: issues for the clinician

Diabetes may become a disabling disease due to diverse mechanisms. Many patients have evidence of physical or cognitive impairments that can markedly influence their ability to diabetes self manage and adversely affect possible outcomes of diabetes care. A screening process for impairment is therefore needed and in frail patients a comprehensive gerontological assessment should be used to improve the efficiency of care. A diabetes educational programme adapted to this population, which has involved the main care-giver has shown its efficacy to improve risk factor control and quality of life in a safer way. The experience of case-managers according to a model of heart failure may be promising for the future.

Midlife muscle strength and human longevity up to age 100 years: a 44-year prospective study among a decedent cohort

We studied prospectively the midlife handgrip strength, living habits, and parents' longevity as predictors of length of life up to becoming a centenarian. The participants were 2,239 men from the Honolulu Heart Program/Honolulu-Asia Aging Study who were born before the end of June 1909 and who took part in baseline physical assessment in 1965-1968, when they were 56-68 years old. Deaths were followed until the end of June 2009 for 44 years with complete ascertainment. Longevity was categorized as centenarian (≥100 years, n = 47), nonagenarian (90-99 years, n = 545), octogenarian (80-89 years, n = 847), and ≤79 years (n = 801, reference). The average survival after baseline was 20.8 years (SD = 9.62). Compared with people who died at the age of ≤79 years, centenarians belonged 2.5 times (odds ratio (OR) = 2.52, 95% confidence interval (CI) = 1.23-5.10) more often to the highest third of grip strength in midlife, were never smokers (OR = 5.75 95% CI = 3.06-10.80), had participated in physical activity outside work (OR = 1.13 per daily hour, 95% CI = 1.02-1.25), and had a long-lived mother (≥80 vs. ≤60 years, OR = 2.3, 95% CI = 1.06-5.01). Associations for nonagenarians and octogenarians were parallel, but weaker. Multivariate modeling showed that mother's longevity and offspring's grip strength operated through the same or overlapping pathway to longevity. High midlife grip strength and long-lived mother may indicate resilience to aging, which, combined with healthy lifestyle, increases the probability of extreme longevity.

Development and validation of criterion-referenced clinically relevant fitness standards for maintaining physical independence in later years

PURPOSE

To develop and validate criterion-referenced fitness standards for older adults that predict the level of capacity needed for maintaining physical independence into later life. The proposed standards were developed for use with a previously validated test battery for older adults-the Senior Fitness Test (Rikli, R. E., & Jones, C. J. (2001). Development and validation of a functional fitness test for community--residing older adults. Journal of Aging and Physical Activity, 6, 127-159; Rikli, R. E., & Jones, C. J. (1999a). Senior fitness test manual. Champaign, IL: Human Kinetics.).

METHODS

A criterion measure to assess physical independence was identified. Next, scores from a subset of 2,140 "moderate-functioning" older adults from a larger cross-sectional database, together with findings from longitudinal research on physical capacity and aging, were used as the basis for proposing fitness standards (performance cut points) associated with having the ability to function independently. Validity and reliability analyses were conducted to test the standards for their accuracy and consistency as predictors of physical independence.

RESULTS

Performance standards are presented for men and women ages 60-94 indicating the level of fitness associated with remaining physically independent until late in life. Reliability and validity indicators for the standards ranged between .79 and .97.

IMPLICATIONS

The proposed standards provide easy-to-use, previously unavailable methods for evaluating physical capacity in older adults relative to that associated with physical independence. Most importantly, the standards can be used in planning interventions that target specific areas of weakness, thus reducing risk for premature loss of mobility and independence.

Sarcopenic obesity and cognitive functioning: the mediating roles of insulin resistance and inflammation?

This study examined the influence of insulin resistance and inflammation on the association between body composition and cognitive performance in older adults, aged 60–69 and aged 70 and older. Subjects included 1127 adults from NHANES 1999–2002. Body composition was categorized based on measurements of muscle mass and waist circumference as sarcopenic nonobese, nonsarcopenic obese, sarcopenic obese, and normal. Using OLS regression models, our findings suggest body composition is not associated with cognitive functioning in adults ages 60–69; however, for adults aged 70 and over, sarcopenia and obesity, either independently or concurrently, were associated with worse cognitive functioning relative to non-sarcopenic non-obese older adults. Furthermore, insulin resistance accounted for a significant proportion of the relationship between cognitive performance and obesity, with or without sarcopenia. Additionally, although high CRP was significantly associated with poorer cognitive functioning in adults ages 60–69, it did not influence the association between body composition and cognitive performance. This study provides evidence that age-related physiological maladaptations, such as metabolic deregulation, which are associated with abdominal fat, may simultaneously contribute to lower cognition and muscle mass, reflecting a degradation of multiple physiological systems.

Patterns and correlates of grip strength change with age in Afro-Caribbean men

BACKGROUND

muscle strength is essential for physical functions and an indicator of morbidity and mortality in older adults. Among the factors associated with muscle strength loss with age, ethnicity has been shown to play an important role.

OBJECTIVE

to examine the patterns and correlates of muscle strength change with age in a population-based cohort of middle-aged and older Afro-Caribbean men.

METHODS

handgrip strength and body composition were measured in 1,710 Afro-Caribbean men. Data were also collected for demographic variables, medical history and lifestyle behaviours.

RESULTS

the age range of the study population was 29-89 years. Grip strength increased below age 50 years, and decreased after age 50 years over 4.5-year follow-up. The average loss in grip strength was 2.2% (0.49% per year) for ages 50 years or older and 3.8% (0.64% per year) for ages 65 years or older. The significant independent predictors of grip strength loss included older age, a greater body mass index, lower initial arm lean mass and greater loss of arm lean mass.

CONCLUSION

Afro-Caribbean men experience a significant decline in muscle strength with advanced age. The major independent factors associated with strength loss were similar to other ethnic groups, including age, body weight and lean mass.

Long-term changes in handgrip strength in men and women--accounting the effect of right censoring due to death

BACKGROUND

Age-related decline in muscle strength is among of the most important factors in the aging process leading to disability. This study examines age-related changes in handgrip strength through a 22-year follow-up in men and women. Because handgrip strength is associated with mortality, this study also accounts for the selection effect of right censoring by comparing the estimates of handgrip strength decline based either on only the handgrip strength data or on the data of both the handgrip strength and survival times.

METHODS

Data are from 1,890 men and women aged 30 years or more at baseline participating in the population-based Mini-Finland Health Examination Survey (1978-1980) with repeated handgrip strength measurement in 2000-2001.

RESULTS

In men aged 31-41 years, the annual decrease in handgrip strength was approximately 3.5 Newtons (N). After that, the decrease accelerated and stabilized around the age of 75 years, being approximately 7.3 N per year. In women, respectively, prior to 45 years, the annual decrease was approximately 2 N and after age 80 years approximately 4 N per year. The estimates for the handgrip strength decline were more pronounced when the right censoring due to death was accounted for, especially for persons aged 65 years and older.

CONCLUSIONS

Our work confirms that the right censoring, which depends on the outcome of interest, should be accounted for in analyses.

Covariance of Isometric and Dynamic Arm Contractions: Multivariate Genetic Analysis

The purpose of the present study was to examine genetic and environmental contributions to individual differences in maximal isometric, concentric and eccentric muscle strength and muscle cross-sectional area (MCSA) of the elbow flexors. A generality versus specificity hypothesis was explored to test whether the 4 strength variables share a genetic component or common factors in the environment or whether the genetic/environmental factors are specific for each strength variable. The 4 variables under study were measured in 25 monozygotic and 16 dizygotic male Caucasian twin pairs (22.4 ± 3.7 years). The multivariate genetic analyses showed that all 4 variables shared a genetic and environmental component, which accounted for 43% and 6% in MCSA (h2= 81%), 47% and 20% in eccentric (h2= 65%), 58% and 4% in isometric (h2= 70%) and 32% and 1% in concentric strength (h2= 32%) respectively. The remaining variation was accounted for by contraction type specific and muscle cross-sectional area specific genetic and environmental effects, which accounted for 38% and 14% in MCSA, 18% and 15% in eccentric, 12% and 26% in isometric and 0% and 67% in concentric strength respectively. This exploratory multivariate study suggests shared pleiotropic gene action for MCSA, eccentric, isometric and concentric strength, with a moderate to high genetic contribution to the variability of these characteristics.

Translational musculoskeletal science: is sarcopenia the next clinical target after osteoporosis?

Translational medicine must increasingly turn its attention to the aging population and the musculoskeletal deterioration that it entails. The latter involves the integrated function of both muscle and bone. Musculoskeletal science has an established interest in such problems in relationship to osteoporosis of bone. The introductory concepts in this paper consider the extent to which loss of muscle mass and function, or sarcopenia, will be the next major translational target. Its epidemiology shows parallels with that of osteoporosis, and the two tissues have a close functional relationship. Its etiology likely involves a loss of motor units combined with cellular signaling and endocrine changes. Finally, the possibility of modification of these physiological changes in the context of management of the sarcopenic condition is considered.

Long-term determinants of muscle strength decline: prospective evidence from the 22-year mini-Finland follow-up survey

OBJECTIVES

To examine long-term changes in handgrip strength and the factors predicting handgrip strength decline.

DESIGN

Longitudinal cohort study with 22 years of follow-up.

SETTING

Population-based Mini-Finland Health Examination Survey in Finland.

PARTICIPANTS

Nine hundred sixty-three men and women aged 30 to 73 at baseline.

MEASUREMENTS

Handgrip strength was measured using a handheld dynamometer at baseline and follow-up. Information on potential risk factors, namely lifestyle and chronic conditions, and their changes throughout the follow-up were based on health interviews.

RESULTS

Based on linear mixed-effect models, midlife physically strenuous work, excess body weight, smoking, cardiovascular disease, hypertension, diabetes mellitus, and asthma predicted muscle strength decline over 22 years of follow-up (P < .05 for all). In addition, pronounced weight loss, becoming physically sedentary, persistent smoking, incident coronary heart disease, other cardiovascular disease, diabetes mellitus, chronic bronchitis, chronic back syndrome, long-lasting cardiovascular disease, hypertension, and asthma were associated with accelerated handgrip strength decline (P < .05 for all).

CONCLUSION

Lifestyle and physical health earlier in life determine rate of muscle strength decline in old age. Efforts should be made to recognize persons at risk in a timely manner and target early interventions to middle-aged persons to slow down muscle strength decline and prevent future functional limitations and disability.

Gender-specific patterns in age-related decline in general health among Danish and Chinese: a cross-national comparative study

AIM

Studies carried out in Western populations have shown age-related changes in multiple health domains together with gender-specific patterns. By focusing on five health domains, self-rated health, hand grip strength, sit-to-stand test, cognitive performance and depression, we examined the age trajectories in general health in a cross-sectional Chinese sample representing the world's largest ethnic population and compare with Danish data that represent Western populations in developed countries.

METHODS

Multiple regression models were fitted to compare patterns across genders and populations together with gender- and population-specific patterns in age-related decline.

RESULTS

Better self-rated health for males than for females was observed in both countries, and Danes reported better health than the Chinese for both genders. For hand grip strength, significant gender differences were shown across countries and significant population differences observed in Danish and Chinese males. There was no population difference in sit-to-stand time across genders. Female Danes outperformed males in cognitive performance. No significant gender differences in depression were observed in both populations.

CONCLUSION

Our cross population analysis identified significant gender and population differences suggesting endogenous biological, physical and social environmental determinants in age-related decline in general health.

Mild thyroid hormone excess is associated with a decreased physical function in elderly men

INTRODUCTION

In the adult, subclinical hyperthyroidism (Shyper) may alter skeletal muscle mass and strength. However, whether these effects are present in elderly subjects is not known. We explored the relationship between mild hyperthyroidism and physical function in a population-based sample of older persons.

METHODS

In a cross-sectional analysis, calf muscle cross-sectional area (CMA), handgrip strength, nerve conduction velocity (NCV), and Short Physical Performance Battery (SPPB) scores were compared between 364 euthyroid (Eut) and 28 Shyper men as well as between 502 Eut and 39 Shyper women. In a longitudinal analysis, we evaluated the relationship between baseline plasma TSH, FT3 and FT4 and the 3-year change in SPPB score in 304 men and 409 women who were euthyroid at enrolment.

RESULTS

At the cross-sectional analysis, Shyper men, but not women, had a significantly (p = 0.02) lower SPPB score than Eut controls, although with comparable CMA, grip strength and NCV, and were more likely to have poor physical performance (odds ratio = 2.97, p < 0.05). Longitudinal analysis showed that in Eut men higher baseline FT4 was significantly (p = 0.02) predictive of a lower SPPB score at the 3-year follow-up.

CONCLUSION

Even a modest thyroid hormone excess is associated with a reduced physical function in elderly men.

Age and gender differences in physical capability levels from mid-life onwards: the harmonisation and meta-analysis of data from eight UK cohort studies

Using data from eight UK cohorts participating in the Healthy Ageing across the Life Course (HALCyon) research programme, with ages at physical capability assessment ranging from 50 to 90+ years, we harmonised data on objective measures of physical capability (i.e. grip strength, chair rising ability, walking speed, timed get up and go, and standing balance performance) and investigated the cross-sectional age and gender differences in these measures. Levels of physical capability were generally lower in study participants of older ages, and men performed better than women (for example, results from meta-analyses (N = 14,213 (5 studies)), found that men had 12.62 kg (11.34, 13.90) higher grip strength than women after adjustment for age and body size), although for walking speed, this gender difference was attenuated after adjustment for body size. There was also evidence that the gender difference in grip strength diminished with increasing age,whereas the gender difference in walking speed widened (p<0.01 for interactions between age and gender in both cases). This study highlights not only the presence of age and gender differences in objective measures of physical capability but provides a demonstration that harmonisation of data from several large cohort studies is possible. These harmonised data are now being used within HALCyon to understand the lifetime social and biological determinants of physical capability and its changes with age.

Forearm muscle size, strength, force, and power in relation to pQCT-derived bone strength at the radius in adults

We aimed to examine the relationship between forearm muscle cross-sectional area (MCSA), muscle force, or rate of torque development (RTD) and 2 estimated radius bone strength indices — compressive bone strength index (BSI) at the wrist and strength strain index in torsion (SSIp) at the shaft — in healthy middle-aged males and females. Distal (4%) and shaft (65%) sites of nondominant forearms were scanned using peripheral quantitative computed tomography (pQCT) in a sample of 48 adults (mean age ± SD, 49.4 ± 2.4 y) to obtain estimated bone strength indices and MCSA. Muscle force, measured by grip dynamometry and wrist flexion RTD, was obtained using an isokinetic dynamometer. Hierarchical linear regressions, adjusted for weight, explained 27% and 36% of the BSI variance at the 4% site in males and premenopausal females, respectively (p < 0.05). At the radius shaft, weight explained 26% (p < 0.05) and 83% (p < 0.01) of SSIp variance. The unique variance of BSI explained by MCSA was 16% in males (p < 0.05) and 31% in females (p < 0.01). Grip force predicted variance in SSIp in males (p < 0.01) and BSI in females (p < 0.05). RTD did not explain any variance in BSI or SSIp. Body weight was the only significant predictor (p < 0.05) of SSIp in females. Although forearm muscle size and grip strength are associated with estimates of radius bone strength at midlife, this relationship appears to be sex dependent. The differences observed between muscle size and strength properties and bone strength at distal and shaft sites of the radius suggest a property-, sex-, and site-specific relationship between muscle and bone in the forearm.

The epidemiology of sarcopenia in community living older adults: what role does lifestyle play?

BACKGROUND: Sarcopenia, the age-related decline in skeletal muscle mass and function, is a relatively poorly understood process which may play an important role in the incidence of physical disability and falls in older adults. Evidence demonstrates that both genetic and environmental factors contribute to increased susceptibility for sarcopenia development, yet some of these factors may represent unavoidable consequences of ageing. METHODS: A review of literature, generally from epidemiological research, was performed to examine the influence that potentially modifiable lifestyle factors (general physical activity, dietary nutrient intake and sun exposure), as well as chronic disease and medication use, may have on sarcopenia progression. RESULTS: The review demonstrated that while physical activity, nutrient intake and sun exposure often decline during ageing, each may have important but differing benefits for the prevention of muscle mass and functional declines in older adults. Conversely, age-related increases in the prevalence of chronic diseases and the subsequent prescription of pharmacotherapy may exacerbate sarcopenia progression. CONCLUSIONS: The prevalence of poor physical activity, diet and sun exposure, as well as chronic disease and medication use, within older adult populations may be modifiable through simple lifestyle and health care interventions. As such, these factors may represent the most effective targets for sarcopenia prevention during the ageing process.

Benefits of home-based rocking-chair exercise for physical performance in community-dwelling elderly women: a randomized controlled trial

BACKGROUND AND AIMS

Home-based exercise is a viable alternative for older adults with difficulties in exercise opportunities outside the home. The aim of this study was to investigate the benefits of home-based rocking-chair training, and its effects on the physical performance of elderly women.

METHODS

Community- dwelling women (n=51) aged 73-87 years were randomly assigned to the rocking-chair group (RCG, n=26) or control group (CG, n=25) by drawing lots. Baseline and outcome measurements were hand grip strength, maximal isometric knee extension, maximal walking speed over 10 meters, rising from a chair five times, and the Berg Balance Scale (BBS). The RCG carried out a six-week rocking-chair training program at home, involving ten sessions per week, twice a day for 15 minutes per session, and ten different movements. The CG continued their usual daily lives. After three months, the RCG responded to a mail questionnaire.

RESULTS

After the intervention, the RCG improved and the CG declined. The data showed significant interactions of group by time in the BBS score (p=0.001), maximal knee extension strength (p=0.006) and maximal walking speed (p=0.046), which indicates that the change between groups during the follow-up period was significant. Adherence to the training protocol was high (96%). After three months, the exercise program had become a regular home exercise habit for 88.5% of the subjects.

CONCLUSIONS

Results indicate that home-based elderly women benefit from this easily implemented rocking-chair exercise program. The subjects became motivated to participate in training and continued the exercises. This is a promising alternative exercise method for maintaining physical activity and leads to improvements in physical performance.