Muscle strength: clinical and prognostic value of hand-grip dynamometry

Hand grip strength as a physical biomarker of aging from the perspective of a Fibonacci mathematical modeling

Background

The Golden Ratio (GR) and the Fibonacci sequence have wide applications in biodiversity research, and recent studies indicate that the GR can be highlighted in the organization and physiological functioning of many body systems. The aim of this cross-sectional descriptive study is to determine the applicability of a mathematical model derived from the Fibonacci sequence to investigate the changes in hand grip strength (HGS) induced by the aging process.

Methods

We assessed the HGS for both hands, using a Saehan hydraulic hand dynamometer in a group of autonomous elderly subjects. One hundred twenty 55-year-old subjects (58 males and 62 females) and seventy 89-year-old subjects (31 men and 39 women) were included in the study group. All subjects were completely independent or independent with minimal assistance in activities of daily living (ADL), as determined after applying the Barthel index of ADL. The data series were statistically processed using descriptive statistics (univariate analysis) and inferential statistical methods (the t test for unpaired groups, with effect size measure – Cohen’s d and the ratio of the means method).

Results

The decline of the relative HGS between the two age groups can be expressed by values close to the GR value (p < 0.001), both in relation to body symmetry (left hand/right hand evaluation) and laterality (dominant hand/non-dominant hand evaluation), for both sexes. For the whole group of men and women, the rhythm of HGS decline may be expressed by a value (1.61) notably close to the GR, regardless of body symmetry or laterality.

Conclusions

The common pattern of the relative HGS reduction between 55 and 89 years, as expressed by a value notably close to GR, can be considered to be an expression of a specific and predictable manifestation of the aging process, in the absence of disability.

Low handgrip strength is closely associated with chronic low back pain among women aged 50 years or older: A cross-sectional study using a national health survey

Object

This study aimed to analyze the association between low handgrip strength (HGS) and low back pain (LBP) according to physical activity (PA) in the general population aged over 50 years.

Methods

Nationwide health surveys and examinations were performed in a cross-sectional representative of the Korean general population (n = 7,550 in 2014, n = 7,380 in 2015). Chronic LBP status was determined by self-reported survey responses with respect to the occurrence of LBP for more than 30 days during the previous 3 months. Maximal HGS was determined as the maximal strength of the dominant hand, and low HGS was defined as measurement in the lower 20th percentile of HGS measurements for the general population. High PA was defined as muscle-strengthening exercise for at least 3 days within 1 week. Demographics, medical history, and other variables were used to analyze adjusted weighted logistic regression models with propensity score matching. After propensity score matching, 429 participants were included in each group.

Results

Analysis was confined to those aged 50–89 years who responded to the chronic LBP survey and had no missing data on HGS. Low HGS and LBP showed significant association in the crude logistic regression model. In the multiple logistic regression model, after adjusting for confounding factors, low HGS was significantly associated with LBP in women with low PA (adjusted odds ratio [aOR]: 1.75, p = 0.047). In the logistic regression model after propensity score matching, low HGS was also significantly related to LBP in women with low PA (aOR: 3.12, p = 0.004).

Conclusions

Our study showed the relationship between low HGS and LBP using a cross-sectional Korean population-based health survey. Low HGS in women aged over 50 years with low PA was significantly associated with the presence of LBP.

Handgrip Strength and Health in Aging Adults

Handgrip strength (HGS) is often used as an indicator of overall muscle strength for aging adults, and low HGS is associated with a variety of poor health outcomes including chronic morbidities, functional disabilities, and all-cause mortality. As public health initiatives and programs target the preservation of muscle strength for aging adults, it is important to understand how HGS factors into the disabling process and the sequence of health events that connect low HGS with premature mortality. Such information will help to inform interventions designed to slow the disabling process and improve health outcomes for those at risk for muscle weakness. Further, unraveling the disabling process and identifying the role of weakness throughout the life course will help to facilitate the adoption of HGS measurements into clinical practice for healthcare providers and their patients. The purposes of this article were to (1) highlight evidence demonstrating the associations between HGS and clinically relevant health outcomes, (2) provide directions for future research in HGS and health, and (3) propose a sequence of health-related events that may better explain the role of muscle weakness in the disabling process.

Handgrip strength in old and oldest old Swiss adults - a cross-sectional study

Background

Handgrip strength is indicative of overall physical health and mobility in the elderly. A reduction in strength below a certain threshold severely increases the risk of mobility limitations and is predictive for adverse outcomes such as dependence in daily activities and mortality. An overview of age- and geography- specific handgrip strength values in older adults provide a reference for further investigations and measures in clinical practice to identify people at risk for clinically meaningful weakness. The aim of this study was to evaluate handgrip strength in the Swiss-German population aged 75 and over.

Methods

In a cross-sectional study, maximal isometric handgrip strength of the dominant hand was evaluated in 244 Swiss people aged 75 years and over (62.7% women), with mean age (SD) of 84.5 (5.6) years in men and 83.1 (5.9) years in women. Demographic data and information about comorbidities, medication, fall history, global cognitive function, self-reported physical activity and dependence in activities of daily living were collected, and correlated with grip strength measures. Age- and gender specific grip strength values are reported as means, standard deviations and standard error of mean.

Results

Sex-stratified handgrip strength was significantly lower with advancing age in men (p < .01), from 37.7 (6.5) kg to 25.6 (7.6) kg and in women (p < .01) from 22.2 (4.0) kg to 16.5 (4.7) kg. Handgrip strength in our sample was significantly higher than in Southern European countries. Handgrip strength was independently associated with age, height and ADL dependence in men and women. Overall, 44% of men and 53% of women had handgrip strength measures that were below the clinically relevant threshold for mobility limitations.

Conclusion

This study reports the age- and sex-stratified reference values for handgrip strength in a representative sample of the Swiss population, aged 75–99 years. Although grip strength decreased with advancing age in both sexes; the relative decline was greater in men than women. Nonetheless men had significantly higher grip strength in all age groups. While the Swiss population sampled had greater grip strength than that reported in other European countries, about 50% were still classified as at risk of mobility limitations.

Association of Serum TSH With Handgrip Strength in Community-Dwelling Euthyroid Elderly

CONTEXT

Despite apparent muscle weakness in overt or even subclinical hyperthyroidism, the effects of thyroid function in the reference range on muscle strength are unknown.

OBJECTIVE

To investigate the association of serum TSH and free T4 with handgrip strength (HGS) in euthyroid elderly.

DESIGN AND SETTING

A nationally representative population-based, cross-sectional study from the Korea National Health and Nutrition Examination Surveys.

PARTICIPANTS

A total of 650 men aged ≥50 years and 533 postmenopausal women.

MAIN OUTCOME MEASURES

HGS was measured using a digital grip strength dynamometer, and low muscle strength was defined based on the Korean specific cutoff point of HGS (28.9 and 16.8 kg in men and women, respectively).

RESULTS

After adjustment for confounders, lower serum TSH but not free T4 was associated with lower HGS in men (P = 0.032). Compared with men with high-normal TSH, those with low-normal TSH consistently showed 5.0% lower HGS (P = 0.027), with a linear decrease in HGS across decreasing serum TSH quartiles (P for trend = 0.018). Men with low muscle strength had 22.0% lower serum TSH than those without (P = 0.015), and the odds for the risk of low muscle strength was 3.76 times higher among men with low-normal TSH than it was among those with high-normal TSH (P = 0.021). However, these associations were not observed in postmenopausal women.

CONCLUSIONS

These results suggest that serum TSH level at the lower end of reference range may be associated with low muscle strength, especially in older men.

Neuromodulation treats Chikungunya arthralgia: a randomized controlled trial

The Chikungunya (CHIK) virus is epidemic in Brazil, with 170,000 cases in the first half of 2016. More than 60% of patients present relapsing and remitting chronic arthralgia with debilitating pain lasting years. There are no specific therapeutic agents to treat and rehabilitee infected persons with CHIK. Persistent pain can lead to incapacitation, requiring long-term pharmacological treatment. Advances in non-pharmacological treatments are necessary to promote pain relief without side effects and to restore functionality. Clinical trials indicate transcranial direct current stimulation (tDCS) can treat a broad range of chronic pain disorders, including diffuse neuromuscular pain and arthralgia. Here, we demonstrate that the tDCS across the primary motor cortex significantly reduces pain in the chronic phase of CHIK. High-resolution computational model was created to analyze the cortical electric field generated during tDCS and a diffuse and clustered brain current flow including M1 ipsilateral and contralateral, left DLPFC, nucleus accumbens, and cingulate was found. Our findings suggest tDCS could be an effective, inexpensive and deployable therapy to areas lacking resources with a significant number of patients with chronic CHIK persistent pain.

Association of Handgrip Strength with Dietary Intake in the Korean Population: Findings Based on the Seventh Korea National Health and Nutrition Examination Survey (KNHANES VII-1), 2016

To evaluate associations between handgrip strength (HGS) and dietary nutrients, this study of a representative Korean population of 1553 adults aged ≥60 years (706 men and 847 women) analyzed data from the Korea National Health and Nutrition Examination Survey (2016). HGS was measured in both hands three times using a digital grip strength dynamometer. Dietary intake data were collected by the 24-h recall method through computer-assisted personal interviews. The study population had a mean age of 70.1 years, body mass index (BMI) of 24.2 kg/m², and HGS of 35.7 kg in men, 21.2 kg in women. Total energy (r = 0.411), protein (r = 0.217), polyunsaturated fatty acid (PUFA) (r = 0.269), fiber (r = 0.272), and vitamin C (r = 0.098) were positively correlated with HGS. In multivariable regression analysis, PUFA (β = 0.083) and vitamin C (β = 0.003) were positively associated with HGS among women. Fiber (β = 0.071) and vitamin C (β = 0.006) showed a positive association with HGS among men. Community-dwelling older men and women with higher levels of PUFA, fiber, and vitamin C in their diet were more likely to have greater HGS even after adjusting for age, total calorie intake, BMI, chronic diseases and health-related habits.

Muscular grip strength normative values for a Korean population from the Korea National Health and Nutrition Examination Survey, 2014-2015

Introduction

Muscle weakness is linked to a range of adverse health outcomes across the lifespan including mortality, morbidity, and disability. Because lifestyles and body composition are quite different between Western and Asian countries, there is an urgent need to establish normative grip strength values for individuals of Asian descent. This study presents normative data for hand grip strength in a Korean population-representative sample.

Methods

A sample of 11,073 individuals (age 10–80 years) was included from the Sixth Korea National Health and Nutrition Examination Survey, 2014–2015. Isometric grip strength was assessed using a handheld dynamometer. Relative grip strength was calculated as the maximum absolute grip strength divided by body mass index. Means, standard error, and quintiles for grip strength and relative grip strength were analyzed per 5-year age group for each sex. To create growth charts for grip strength and relative grip strength, parametric quantile regression was used.

Results

In males, absolute grip strength increased quickly starting from 10 years of age until approximately 20 years of age. In females, there was gradual growth until approximately 15 years of age. Grip strength continued to increase until a peak between ages 30 and 39 years, and then declined from midlife onwards in both sexes. Our data showed that the prevalence of weak grip strength increased rapidly in late adult life based on a T-score of -2 standard deviations below the sex-specific peak mean (equivalent to 33 kg in males and 20 kg in females). Approximately 20% of subjects had weak grip strength at age 65–69 years.

Conclusion

This was the first study to establish normative reference values for grip strength across the lifespan in a Korean population aged 10–80 years. Percentiles of grip strength will inform clinical assessments and will help identify thresholds for the identification of muscle weakness.

Whey protein supplementation for the preservation of mass and muscular strength of patients with heart failure: study protocol for a randomized controlled trial

Background

Heart failure (HF) is an important public health problem, considered a new epidemic with high morbidity and mortality. The progression of HF often determines weight reduction, muscle mass loss, and reduced physical ability. Whey protein supplementation may increase the effects of exercise on strength and muscle mass, in addition to promoting improved endothelial function, body composition and quality of life. However, studies are needed to evaluate its benefits in patients with HF.

Methods/design

This is a double-blind, randomized, placebo-controlled clinical trial in which patients with HF will be randomly allocated to two groups to receive supplementation with whey protein or placebo, associated with supervised exercise, for 12 weeks. The frequency of exercise will be three times a week. The study variables will be evaluated at baseline and 12 weeks. The main outcome will be maintenance of muscle mass and strength. Microvascular reactivity, quality of life, and inflammatory parameters will be evaluated as secondary outcomes.

Discussion

HF is associated with severe loss of muscle mass and strength, directly contributing to exercise intolerance and inability to maintain daily life activities, becoming a strong predictor of reduced quality of life and mortality. The results of this study will add to the evidence base for providing new dietary recommendations.

Trial registration

ClinicalTrials.gov, ID: NCT03142399. Registered on 29 May 2016. Effect of Whey Protein’ Supplementation and Exercise in Patients with Heart Failure (PROT-HF).

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2811-4) contains supplementary material, which is available to authorized users.

Association of Anthropometric and Nutrition Status Indicators with Hand Grip Strength and Gait Speed in Older Adults

BACKGROUND

How nutrition status indicators relate to function in older adults is an issue that needs to be explored. This study aimed to quantify the associations of anthropometric parameters and nutrition status indicators with hand grip strength (HGS) and gait speed (GS) in older adults.

METHODS

A cross-sectional observational study was conducted in a population-based sample of 1500 older adults ≥65 years old. Logistic regression models were used to explore the associations between anthropometric, nutrition, and functional measures.

RESULTS

Lower values of height, mid-arm muscle circumference, and calf circumference, as well as higher values of waist circumference, were associated with both low GS and HGS. The adjusted odds ratio (OR) for low GS was around 2-fold higher in participants presenting risk for undernutrition or undernutrition. The adjusted OR (95% confidence interval) for low HGS was 1.54 (1.01-2.36) in women and 1.57 (0.91-2.72) in men at risk for undernutrition/undernutrition.

CONCLUSIONS

In older adults, lower values of height and calf circumference, as well as higher waist circumference, were associated with both low GS and HGS. Lower values of mid-arm muscle circumference were also associated with low values of both functional parameters only in men. The risk for undernutrition/undernutrition was more strongly associated with low GS than with low HGS in both women and men.

Exercise assessments and trainings of pulmonary rehabilitation in COPD: a literature review

Skeletal muscle dysfunction leads to reduction in activity in patients with COPD. As an essential part of the management of COPD, pulmonary rehabilitation (PR) alleviates dyspnea and fatigue, improves exercise tolerance and health-related quality of life, and reduces hospital admissions and mortality for COPD patients. Exercise is the key component of PR, which is composed of exercise assessment and training therapy. To evaluate PR’s application in clinical practice, this article summarizes the common methods of exercise measurement and exercise training for patients with COPD. Exercise assessments should calculate patients’ symptoms, endurance, strength, and health-related quality of life. After calculation, detailed exercise therapies should be developed, which may involve endurance, strength, and respiratory training. The detailed exercise training of each modality is mentioned in this review. Although various methods and therapies of PR have been used in COPD patients, developing an individualized exercise training prescription is the target. More studies are warranted to support the evidence and examine the effects of long-term benefits of exercise training for patients with COPD in each stage.

Handgrip fatiguing exercise can provide objective assessment of cancer-related fatigue: a pilot study

PURPOSE

As a subjective symptom, cancer-related fatigue is assessed via patient-reported outcomes. Due to the inherent bias of such evaluation, screening and treatment for cancer-related fatigue remains suboptimal. The purpose is to evaluate whether objective cancer patients' hand muscle mechanical parameters (maximal force, critical force, force variability) extracted from a fatiguing handgrip exercise may be correlated to the different dimensions (physical, emotional, and cognitive) of cancer-related fatigue.

METHODS

Fourteen women with advanced breast cancer, still under or having previously received chemotherapy within the preceding 3 months, and 11 healthy women participated to the present study. Cancer-related fatigue was first assessed through the EORTC QLQ-30 and its fatigue module. Fatigability was then measured during 60 maximal repeated handgrip contractions. The maximum force, critical force (asymptote of the force-time evolution), and force variability (root mean square of the successive differences) were extracted. Multiple regression models were performed to investigate the influence of the force parameters on cancer-related fatigue's dimensions.

RESULTS

The multiple linear regression analysis evidenced that physical fatigue was best explained by maximum force and critical force (r = 0.81; p = 0.029). The emotional fatigue was best explained by maximum force, critical force, and force variability (r = 0.83; p = 0.008). The cognitive fatigue was best explained by critical force and force variability (r = 0.62; p = 0.035).

CONCLUSION

The handgrip maximal force, critical force, and force variability may offer objective measures of the different dimensions of cancer-related fatigue and could provide a complementary approach to the patient reported outcomes.

Relationship between muscle strength and fall episodes among the elderly: the Yilan study, Taiwan

Background

Fall episodes are not unusual among community residents, especially the elderly, and lower muscle strength is an important issue to address in order to prevent falls.

Methods

A community health survey was conducted in a suburban area of Taiwan, and 1067 older adults were selected for enrollment in the present study. All the enrolled subjects had been visited at their homes; the subjects’ strength of both hands and muscle mass of both legs were measured and well-established questionnaires were finished by certificated paramedic staffs.

Results

The incidence of fall episodes in the previous 1 year in the Yilan elderly population was 15.1%, and the female predominance was significant. A significantly higher prevalence of cataracts was found in group who experienced a fall in the past year (64% vs. 54.9% in the non-fall group). Mild or more severe dementia was much more prevalent in the group who experienced a recent fall (33.8% vs. 25.7% in the non-fall group). The strength of both hands tested as the physical function was 17.6 ± 8.0 kg in the recent fall group, significantly weaker than that in the non-fall group (20.7 ± 8.7 kg). Multivariate regression analysis revealed a greater weekly exercise duration and greater strength of both hands reduced the occurrence of falls among the whole and the female population. The standardized effect sizes of hand grip strength between both groups, not trivial, were 0.29 and 0.37 for the total population and the female subpopulation respectively.

Conclusions

Less weekly exercise duration and weaker muscle strength were f ound to be independent risk factors of fall episode(s) in an elderly Taiwanese population, especially in the female sub-population. Muscle strength, measured by average of both hands grip strength, was the most significantly factor of one-year fall episode(s) accessed retrospectively.

Handgrip strength is associated with improved spirometry in adolescents

Introduction

Pulmonary rehabilitation, including aerobic exercise and strength training, improves function, such as spirometric indices, in lung disease. However, we found spirometry did not correlate with physical activity (PA) in healthy adolescents (Smith ERJ: 42(4), 2016). To address whether muscle strength did, we measured these adolescents’ handgrip strength and correlated it with spirometry.

Methods

In 1846 non-smoking, non-asthmatic Germans (age 15.2 years, 47% male), we modeled spirometric indices as functions of handgrip strength by linear regression in each sex, corrected for factors including age, height, and lean body mass.

Results

Handgrip averaged 35.4 (SD 7.3) kg in boys, 26.6 (4.2) in girls. Spirometric volumes and flows increased linearly with handgrip. In boys each kg handgrip was associated with about 28 mL greater FEV1 and FVC; 60 mL/sec faster PEF; and 38 mL/sec faster FEF2575. Effects were 10–30% smaller in girls (all p<0.0001) and stable when Z-scores for spirometry and grip were modeled, after further correction for environment and/or other exposures, and consistent across stages of puberty.

Conclusions

Grip strength was associated with spirometry in a cohort of healthy adolescents whose PA was not. Thus, research into PA’s relationship with lung function should consider strength as well as total PA. Strength training may benefit healthy lungs; interventions are needed to prove causality.

Reference values for hand grip strength in the South Korean population

Objective

To establish reference values for hand grip strength (HGS) in a healthy Korean population and to identify the dependent anthropometric variables that affect HGS.

Methods

Based on the sixth Korea National Health and Nutrition Examination Survey from 2014 to 2015, we analyzed the HGS data of 7,969 South Koreans. Individuals with specific chronic diseases and who reported poor subjective health status were excluded to ensure a healthy population sample. Means with standard deviations (SDs) and 95% confidence intervals were calculated for each 5-year interval starting from 10 years of age. To determine the relationship between HGS and anthropometric variables, we performed correlation analyses between HGS and height, weight, and body mass index (BMI). Additionally, based on these findings, the cut-off value for low HGS was presented by deriving -2SD values of healthy young adults as recommended by the European Working Group on Sarcopenia in Older People.

Results

The mean age and BMI of men and women were 38.3 and 38.2 years and 23.8 and 22.4 kg/m², respectively. Mean HGS of the dominant hand in men and women was 39.5 and 24.2 kg, respectively. The peak in HGS was at 35–39 years of age, after which HGS decreased in both sexes. HGS was significantly correlated with height, weight, and BMI. The cut-off values for weak HGS were < 28.9 and < 16.8 kg in men and women, respectively.

Conclusion

These results provide useful reference values to assess HGS in patients who undergo hand surgery or who have various diseases that affect HGS. Moreover, a cut-off value for low HGS may help in defining sarcopenia among the Korean population.

Differences in Prevalence of Muscle Weakness (Sarcopenia) in Haemodialysis Patients Determined by Hand Grip Strength Due to Variation in Guideline Definitions of Sarcopenia

BACKGROUND

Muscle weakness is associated with increased mortality, and hemodialysis (HD) patients are at an increased risk for muscle loss. There is no agreed definition for muscle weakness, so we determined whether using different cut-off criteria recommended by guideline groups altered the prevalence in HD patients.

METHODS

We measured hand grip strength (HGS) in HD outpatients, comparing HGS with clinical guideline cut-offs (European Working Group on Sarcopenia in Older People [EWGSOP] and North American Foundation for the National Institutes of Health Sarcopenia Project [FNIH]) used to define muscle wasting (sarcopenia) with age-matched and gender-matched normative data.

RESULTS

We studied 459 patients, 61.4% male, 47.3% diabetic. The prevalence of muscle weakness was significantly different when measuring HGS; 84.5% using the EWGSOP cut-off and 73.2% with FNIH criteria, and 75.2% using North American normative data and 56.6% U.K. normative data (P < .01). On logistic regression, muscle weakness was associated with age (odds ratio [OR] 1.05, P < .001), weight (OR 0.96, P < .001), serum albumin (OR 0.89, P = .007), and being nondiabetic (OR 0.31, P = .001). Of patients with no comorbidity, 66.7% were weak when compared with 93.8% with the highest comorbidity scores (P < .001).

CONCLUSION

There is currently no agreed universal definition for sarcopenia, but the EWGSOP and FNIH advocate HGS cut-offs as part of their definition. The prevalence of muscle weakness varies according to cut-off and whether age-matched and gender-matched normative data are used. In addition, patient characteristics in terms of age and comorbidity determine the prevalence of muscle weakness.

Muscle Weakness and Physical Disability in Older Americans: Longitudinal Findings from the U.S. Health and Retirement Study

IMPORTANCE

Muscle weakness is an important indicator of disability, chronic disease and mortality. While we recently proposed sex/race specific grip strength cutpoints for clinical muscle weakness in a diverse, nationally representative sample of older Americans, the extent to which these cutpoints predict physical disability remains unknown.

OBJECTIVE

To examine whether sex/race specific muscle weakness cutpoints predict physical disability status in a nationally representative sample of Americans age 65+.

DESIGN

We used data from the 2006-2010 Health and Retirement Study. Fully-adjusted, weighted multinomial logistic regression models were used to quantify the odds of experiencing the onset, progression or persistence of disability in activities of daily living (ADL) among weak versus non-weak individuals over a 2-year period.

SETTING

General community, nationally representative sample of older Americans.

PARTICIPANTS

Population-based, community dwelling sample of older American adults aged 65-years+; 57 percent were women, 91% were White and the mean age was 75 years. Main Outcome(s) and Measure(s): The primary outcome of interest was disability dynamics, defined by changes in ADL status across at 2- year period. The primary exposure was clinical muscle weakness as defined by previously identified cutpoints. Hypotheses were formulated before analyses were conducted.

RESULTS

In this nationally representative sample (n= 8,725), 44% of individuals were classified as weak at baseline. At follow-up, 55% remained independent with no change in their ADL status, 11% had an onset of disability and 4% progressed in their disability status. The odds of experiencing an onset of ADL disability was 54% higher among weak individuals compared those who were not weak at baseline (OR= 1.54, 95% CI= 1.54, 1.5, p<.0001); the odds of experiencing a progression in physical disability status was 2.16 times higher among those who were weak at baseline compared to non-weak individuals (OR= 2.16, 95% CI= 2.15, 2.16, p<.0001).

CONCLUSIONS

This is the first study to use grip strength weakness cut-points to identify those who may be at greatest risk for experiencing physical disability in later life. Results underscore the importance of using population-specific cutpoints for clinical weakness in order to identify individuals at greatest risk for adverse health outcomes.

The Association Between Sleep Duration and Hand Grip Strength in Community-Dwelling Older Adults: The Yilan Study, Taiwan

Study objectives

Different pathomechanisms may underlie the age-related decline in muscle mass and muscle power in older adults. This study aimed to examine the independent relationship between sleep duration and muscle power.

Methods

Older adults, aged 65 years and older, were randomly selected to participate in a community-based survey in Yilan city, Taiwan. Data on self-reported sleep duration, sociodemographic information, lifestyle, chronic medical and mental health conditions, sleep-related parameters, and anthropometric measurements were collected. Participants who slept ≤4 hr, 5 hr, 6-7 hr, 8 hr, and ≥9 hr were defined as shortest, short, mid-range, long, and longest sleepers, respectively. Muscle power was estimated using hand grip strength.

Results

A total of 1081 individuals participated. Their average age was 76.3 ± 6.1 years, and 59.4% were female. After controlling for covariates, including muscle mass of the upper extremities, both long (estimated mean [95% confidence interval, CI]: 19.2 [18.2-20.2], p = .03) and longest sleepers (estimated mean [95% CI]: 17.8 [16.4-19.2], p = .001) had weaker hand grip strength than mid-range sleepers (estimated mean [95% CI]: 20.9 [20.3-21.4]). When stratified by sex, the association between longest sleep duration and weaker hand grip strength was noted among men only.

Conclusions

Older adults with long sleep duration had weaker hand grip strength irrespective of muscle mass. This finding suggests that decreased muscle power may mediate or confound the relationship between long sleep duration and adverse health outcomes.

Hand grip strength and chronic obstructive pulmonary disease in Korea: an analysis in KNHANES VI

Background

Muscle mass is known to be associated with mortality in elderly adults. Because hand grip strength (HGS) is known as a simple assessment tool for muscular strength, many researchers have studied the association between HGS and disease. However, empirical evidence for the relationship between chronic obstructive pulmonary disease (COPD) and HGS is still controversial. The aim of this study was to evaluate the association between COPD and HGS, using Korean population data.

Methods

This was a population-based cross-sectional study. Data were obtained from the sixth Korean National Health and Nutrition Examination Survey, which was conducted from 2013 to 2015. To reduce the effects of HGS-related factors and potential confounding factors, propensity score matching was used to match subjects with and without COPD.

Results

Among 14,930 subjects, 832 were enrolled in each group (non-COPD and COPD) after propensity score matching. COPD subjects did not have lower HGS than non-COPD subjects (non-COPD vs COPD, male, 38.0±7.0 vs 38.9±7.0 kg, P=0.044, female, 23.8±4.6 vs 24.2±4.9 kg, P=0.342). Lung function was classified by Global Initiative for Chronic Obstructive Lung Disease stages and was not significantly associated with HGS. For male COPD subjects, there was a significant correlation between HGS and the EuroQol Five-Dimension Questionnaire (EQ5D) utility score index, which is an indicator of quality of life that adjusts for age and body mass index (r=0.201, P<0.001). The correlation was absent for female subjects (r=0.098, P=0.170).

Conclusion

COPD subjects did not have lower HGS than non-COPD subjects. HGS did not associate with lung function. However, the HGS of male COPD subjects was positively associated with EQ5D utility score index, an indicator of quality of life. HGS may be helpful as an additional method to the evaluation of quality of life in male COPD patients.

Mean Hand Grip Strength and Cut-off Value for Sarcopenia in Korean Adults Using KNHANES VI

The purpose of this study was to report age- and gender-specific distribution of the hand grip strength (HGS) using data from the Korea National Health and Nutrition Examination Survey (KNHANES) VI-3 (2015) survey and determine cut-off values for low muscle strength of HGS of Koreans. Of a total of 7,380 participants, 4,553 were subjected to measurements of HGS, including 1,997 men and 2,556 women with a mean age of 49.3 years (range, 19-80 years). The mean ages of men and women were 49.0 and 49.5 years, respectively. HGS was measured using a digital hand dynamometer. It was defined as maximal measured grip strength of the dominant hand. The cut-off value for low muscle strength was defined as the lower 20th percentile of HGS of the study population. Maximum grip strength of men was significantly higher than that of women (40.2 kg in men vs. 24.2 kg in women, P < 0.001). The mean HGS was increased from the age of 19 to 39 years. It was peaked in the age of 35 to 39 years range for both men and women. It was then decreased after 39 years. The cut-off values of HGS in male and female elderly healthy populations were 28.6 and 16.4 kg, respectively. These data might be used as reference values when evaluating sarcopenia and assessing hand injuries.

Reference equations for handgrip strength: Normative values in young adult and middle-aged subjects

BACKGROUND & AIMS

Handgrip strength (HS) has been widely used as a functionality parameter of the upper limbs (UL) and general health. The measurement of HS by dynamometry is a low cost, non-invasive method of simple applicability, widely used in pulmonary rehabilitation and in critical care units. However, there are no reports in the literature of reference equations for the Brazilian population involving young and middle-aged adults. The aim of this study was to establish reference equations to predict normal HS for young and middle-aged adults through demographic and anthropometric data.

METHODS

This is a cross-sectional study with a sample of 80 healthy subjects (40 men and 40 women), aged 20-60 years. Inclusion criteria were: 1) BMI between 18.5 and 30 kg/m²; 2) presence of dominant hand; 3) no cardiac, pulmonary, metabolic, or neurologic diseases; 4) lack of musculoskeletal disorders; 5) no history of fractures or trauma of the UL. Anthropometric measurements of the UL were obtained by a tape (hand length and width, forearm circumference and length). The dominance of hands was defined by the Dutch Handedness Questionnaire. HS measures were obtained by a manual hydraulic dynamometer, according to the recommendations of the American Association of Hand Therapists. Data were analyzed with SPSS for Windows, version 17.0, and treated with descriptive and inferential analysis. Normality was evaluated by Kolmogorov-Smirnov. Pearson or Spearman coefficients and multiple regression analysis were also used.

RESULTS

HS was significantly higher for men compared to women, and also higher for the dominant hand (HSD) compared to the non-dominant hand (HSND) (p < 0.05). No significant differences were found for HS between the age groups 20-30, 30-40, 40-50 and 50-60 years (p > 0.05). No correlation was found between HS and age. A weak correlation was found between HS and BMI. A moderate correlation of HS was observed with weight and height. Finally, moderate and high correlations were found between HS and anthropometric variables of UL. The best reference equations with R², adjusted to 0.71 and 0.70, were respectively: HSD_kg = -15.490 + (10.787 × Gender _{male=1; female=0}) + (0.558 × Forearm circumference) + (1.763 × Hand Length); HSND_kg = -9.887 + (12.832 × Gender _{male=1; female=0}) + (2.028 × Hand Length).

CONCLUSION

The variability of HS is largely explained by gender, forearm circumference, and hand length.

Strong or Weak Handgrip? Normative Reference Values for the German Population across the Life Course Stratified by Sex, Age, and Body Height

Handgrip strength is an important biomarker of healthy ageing and a powerful predictor of future morbidity and mortality both in younger and older populations. Therefore, the measurement of handgrip strength is increasingly used as a simple but efficient screening tool for health vulnerability. This study presents normative reference values for handgrip strength in Germany for use in research and clinical practice. It is the first study to provide normative data across the life course that is stratified by sex, age, and body height. The study used a nationally representative sample of test participants ages 17–90. It was based on pooled data from five waves of the German Socio-Economic Panel (2006–2014) and involved a total of 11,790 persons living in Germany (providing 25,285 observations). Handgrip strength was measured with a Smedley dynamometer. Results showed that peak mean values of handgrip strength are reached in men’s and women’s 30s and 40s after which handgrip strength declines in linear fashion with age. Following published recommendations, the study used a cut-off at 2 SD below the sex-specific peak mean value across the life course to define a ‘weak grip’. Less than 10% of women and men aged 65–69 were classified as weak according to this definition, shares increasing to about half of the population aged 80–90. Based on survival analysis that linked handgrip strength to a relevant outcome, however, a ‘critically weak grip’ that warrants further examination was estimated to commence already at 1 SD below the group-specific mean value.

Association Between Maximal Bench Press Strength and Isometric Handgrip Strength Among Breast Cancer Survivors

OBJECTIVE

To characterize the relationship between 1-repetition maximum (1-RM) bench press strength and isometric handgrip strength among breast cancer survivors.

DESIGN

Cross-sectional study.

SETTING

Laboratory.

PARTICIPANTS

Community-dwelling breast cancer survivors (N=295).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

1-RM bench press strength was measured with a barbell and exercise bench. Isometric handgrip strength was measured using an isometric dynamometer, with 3 maximal contractions of the left and right hands. All measures were conducted by staff with training in clinical exercise testing.

RESULTS

Among 295 breast cancer survivors, 1-RM bench press strength was 18.2±6.1kg (range, 2.2-43.0kg), and isometric handgrip strength was 23.5±5.8kg (range, 9.0-43.0kg). The strongest correlate of 1-RM bench press strength was the average isometric handgrip strength of both hands (r=.399; P<.0001). Mean difference analysis suggested that the average isometric handgrip strength of both hands overestimated 1-RM bench press strength by 4.7kg (95% limits of agreement, -8.2 to 17.6kg). In a multivariable linear regression model, the average isometric handgrip strength of both hands (β=.31; P<.0001) and age (β=-.20; P<.0001) were positively correlated with 1-RM bench press strength (R²=.23).

CONCLUSIONS

Isometric handgrip strength is a poor surrogate for 1-RM bench press strength among breast cancer survivors. 1-RM bench press strength and isometric handgrip strength quantify distinct components of muscular strength.

Sociodemographic factors related to handgrip strength in children and adolescents in a middle income country: The SALUS study

OBJECTIVE

To determine sociodemographic factors associated with handgrip (HG) strength in a representative sample of children and adolescents from a middle income country.

METHODS

We evaluated youth between the ages of 8 and 17 from a representative sample of individuals from the Department of Santander, Colombia. Anthropometric measures, HG strength, and self-reported physical activity were assessed, and parents/guardians completed sociodemographic questionnairres. Multinomial logistic regression models were used to estimate the association between sociodemographic and anthropometric characteristics and tertiles of relative HG strength. We also produced centile data for raw HG strength using quantile regression.

RESULTS

1,691 young people were evaluated. HG strength increased with age, and was higher in males than females in all age groups. Lower HG strength was associated with indicators of higher socioeconomic status, such as living in an urban area, residence in higher social strata neighborhoods, parent/guardian with secondary education or higher, higher household income, and membership in health insurance schemes. In addition, low HG strength was associated with lower physical activity levels and higher waist-to-hip ratio. In a fully adjusted regression model, all factors remained significant except for health insurance, household income, and physical activity level.

CONCLUSIONS

While age and gender specific HG strength values were substantially lower than contemporary data from high income countries, we found that within this middle income population indicators of higher socioeconomic status were associated with lower HG strength. This analysis also suggests that in countries undergoing rapid nutrition transition, improvements in socioeconomic conditions may be accompanied by reduction in muscle strength.

Association of physical fitness, body composition, cardiometabolic markers and adherence to the Mediterranean diet with bone mineral density in perimenopausal women. The FLAMENCO project

This study aimed to analyse the association of different components of physical fitness, body composition, cardiometabolic markers and the Mediterranean diet with bone mineral density (BMD) in perimenopausal women, and to test which of these components are independently associated with BMD. The sample comprised 197 perimenopausal women (52.6 ± 4.5 years). Physical fitness was assessed with the "Senior Fitness Test" battery and the handgrip strength and Bruce tests. Fat and lean mass and BMD were measured using dual-energy X-ray absorptiometry. We analysed the markers of metabolic syndrome, C-reactive protein, and components of the Mediterranean diet. Handgrip muscle strength (β = 0.212, P = 0.005), body weight (β = 0.244, P = 0.001), BMI (β = 0.180, P = 0.011) and lean mass (β = 0.379, P < 0.001) were positively associated with BMD. No associations were observed between cardiometabolic markers or the Mediterranean diet with BMD (all P > 0.05). When all relevant indicators of BMD were simultaneously considered, lean mass was the only 1 showing an independent association with BMD (β = 0.392, P < 0.001), explaining 14% of the BMD variability. In conclusion, muscle strength might be a marker of BMD in perimenopausal women. However, lean mass was the only factor independently associated with BMD. Future research to determine whether increasing lean mass through specific exercise-based interventions contributes to increasing BMD is warranted.

The association of grip strength from midlife onwards with all-cause and cause-specific mortality over 17 years of follow-up in the Tromsø Study

Background

Grip strength has consistently been found to predict all-cause mortality rates. However, few studies have examined cause-specific mortality or tested age differences in these associations.

Methods

In 1994, grip strength was measured in the population-based Tromsø Study, covering the ages 50–80 years (N=6850). Grip strength was categorised into fifths, and as z-scores. In this cohort study, models with all-cause mortality and deaths from specific causes as the outcome were performed, stratified by sex and age using Cox regression, adjusting for lifestyle-related and health-related factors.

Results

During 17 years of follow-up, 2338 participants died. A 1 SD reduction in grip strength was associated with HR=1.17 (95% CI 1.12 to 1.22) for all-cause mortality in a model adjusted for age, gender and body size. This association was similar across all age groups, in men and women, and robust to adjustment for a range of lifestyle-related and health-related factors. Results for deaths due to cardiovascular disease (CVD), respiratory diseases and external causes resembled those for all-cause mortality, while for cancer, the association was much weaker and not significant after adjustment for lifestyle-related and health-related factors.

Conclusions

Weaker grip strength was associated with increased all-cause mortality rates, with similar effects on deaths due to CVD, respiratory disease and external causes, while a much weaker association was observed for cancer-related deaths. These associations were similar in both genders and across age groups, which supports the hypothesis that grip strength might be a biomarker of ageing over the lifespan.

Mid-upper arm circumference is associated with biochemically determined nutritional status indicators among adolescent girls in Central Mozambique

Biochemically determined nutritional status measurements in low-income countries are often too expensive. Therefore, we hypothesized that some anthropometrical or functional measurements (handgrip) could reflect nutritional status measured by specific biochemical indicators. We did a population-based study from 1 urban area and 2 rural districts in Zambézia Province of Mozambique. The participants (n=386) were non-pregnant adolescent girls between 15 and 18 years of age. 96% had a normal BMI-for-age score. Weight and mid-upper arm circumference (MUAC) were highly correlated (r>0.8) with each other and with total body muscle mass, body mass index (BMI), and with waist circumference, as well as with skinfolds (r>0.6). Upper and total arm lengths were correlated (r>0.7) with height and with each other, and right and left handgrip were correlated only with each other, as were triceps and subscapular skinfolds (r>0.7). Serum albumin correlated negatively with waist circumference (P<.001) and positively with MUAC (P=.007). Stepwise regressions showed that waist circumference, MUAC, weight, and handgrip were important nutritional status indicators in the models using hemoglobin, serum albumin, ferritin, zinc, and plasma retinol concentrations as dependent variables. MUAC could be a valuable anthropometric marker of the overall nutritional status of adolescent girls in low-income countries. When nutrition transition proceeds, waist circumference together with MUAC could form tools for the prediction of worsening of nutritional status.

Neuromuscular function in different stages of sarcopenia

This study applied the screening tool developed by the European Working Group on Sarcopenia in Older People (EWGSOP) on seniors aged over 65years and concurrently tested various laboratory-based indices of neuromuscular function. Twenty-four healthy and independent living older adults (9 men, 15 women) with a mean age of 79.1±5.8years participated. Based on gait speed, handgrip strength and muscle mass all subjects were categorized into one of the three conceptual sarcopenia stages (pre-sarcopenia, sarcopenia, severe sarcopenia). Maximal strength of dorsiflexors in the left leg was measured and voluntary activation was assessed by the interpolated twitch technique. In addition, isometric evoked contractile properties were recorded. Skeletal muscle mass was assessed by ultrasound from nine sites. There were roughly equal number of subjects in each sarcopenic category, and age was not different among the 3 groups. There were no differences in handgrip strength and skeletal muscle mass index among the 3 groups. Gait speed was significantly slower (p<0.01) in the severe sarcopenic subjects compared to the pre-sarcopenic group. With no differences in voluntary activation among the groups, the maximal voluntary contractions (MVCs) for severe sarcopenic subjects were 29% lower (p=0.02) and with 19% slower (p=0.02) voluntary rates of torque development (RTD) compared to sarcopenic subjects. Furthermore, the severe group was 34% lower (p=0.04) with 36% slower (p=0.02) RTD compared to pre-sarcopenic subjects. Peak twitch tension was 54% lower (p<0.01) in the severe group compared with the pre-sarcopenic group. Maximal twitch RTD were 40% (p=0.03) slower for the severe group compared to the sarcopenia group, and 51% slower (p=0.03) compared with the pre-sarcopenia group, but when normalized to peak torques there were no statistical differences. The laboratory tests found neuromuscular differences among the 3 groups which generally supported the classification scheme and helped to illustrate some key factors that could explain differences in functional capacities. These initial findings support the assumption that this categorization is relevant for identifying older adults with different neuromuscular properties. However, further studies are needed to provide more insight into the specific neuromuscular changes in the three sarcopenia stages, and how these changes relate to functional capacity. Such studies could ultimately contribute to identifying optimal interventions to improve neuromuscular functioning.