The Association of Handgrip Strength and Mortality: What Does It Tell Us and What Can We Do With It?

Handgrip strength of young athletes differs based on the type of sport played and age

OBJECTIVE

Handgrip strength may differ depending on the type of sport played during the developmental period. Youth sports in which athletes hold equipment in their hands may be the most effective for improving handgrip strength. This study aimed to examine the age at which differences in handgrip strength appear by comparing sports that involve gripping (kendo) with those that do not involve gripping (soccer) in young athletes.

METHODS

Two hundred and twenty-two male athletes (115 kendo and 107 soccer) between 6 and 15 years old participated in this study. Handgrip strength was measured using a dynamometer, and the average value of both hands was used for analysis. Sports experience was determined when they started practicing each sport. Handgrip strength was compared between sports. Statistical moderation was used to determine if the relationship between sport and handgrip strength depended upon the age of the athlete.

RESULTS

Kendo athletes had significantly higher handgrip strength than soccer athletes (4.77 kg [95% CI: 2.34, 7.19]) in the overall sample. We found that the relationship between sport and handgrip strength depended upon the age of the child (sport*age t = -3.6, p = .004). Using the Johnson-Neyman procedure, we found statistically significant differences between sports from 8.48 years and older.

CONCLUSIONS

Our results suggest that the type of sport played, that is, whether or not an athlete plays with sports equipment in their hands, may influence the development of handgrip strength during the period of growth, and these sports may contribute to a higher level of handgrip strength in adulthood.

Tracking handgrip strength in Kendo athletes from university to middle and older adulthood

OBJECTIVE

This study aimed to compare the current handgrip strength (HGS) of Kendo athletes with their HGS when they were in university (up to 50 years).

METHODS

Eighty male graduates who were Kendo club members during their university days performed anthropometric and HGS measurements, and these HGS were compared with those measured during their university days (mean age of 19.5 years old).

RESULTS

There was no evidence of a statistical difference in HGS between the current measurement and the measurement taken during university [-0.64 (-1.9, 0.67) kg, p = .336]. There was, however, evidence that the difference in HGS depended upon the current age of the individual (t = -6.43, p < .001). When probing the interaction, there were statistical differences between the ages of 24.6 and 38.2 years and between the ages of 47.4 and 69.9 years. Strength increased across time in the younger participants and decreased for those who were older. Between the ages of 38.9 and 46.1 years, there was no evidence of a statistical difference indicating a maintenance of strength.

CONCLUSION

The HGS of Kendo club graduates, which they acquired during their formative years, continued to increase even after they graduated from university and entered their 30s. However, their HGS decreased from age 50, even though they practiced Kendo.

Resistance Exercise Training, a Simple Intervention to Preserve Muscle Mass and Strength in Prostate Cancer Patients on Androgen Deprivation Therapy

Androgen deprivation therapy (ADT) forms the cornerstone in the treatment of advanced prostate cancer. However, by suppressing testosterone ADT results in a decrease of skeletal muscle mass. In this narrative review, we explore the magnitude and mechanisms of ADT-induced muscle mass loss and the consequences for muscle strength and physical performance. Subsequently, we elucidate the effectiveness of supervised resistance exercise training as a means to mitigate these adverse effects. Literature shows that resistance exercise training can effectively counteract ADT-induced loss of appendicular lean body mass and decline in muscle strength, while the effect on physical performances is inconclusive. As resistance exercise training is feasible and can be safely implemented during ADT (with special attention for patients with bone metastases), it should be incorporated in standard clinical care for prostate cancer patients (starting) with ADT.

Association of changes in grip strength with second digit length adjusted for fourth digit length in young children

OBJECTIVES

The factors involved in changes in grip strength (GS) during growth/development are not well known. Findings from cross-sectional studies have indicated that digit lengths are associated with physical fitness, including GS. This study aimed to investigate the association of changes in GS over 1 year and the second (2D) and fourth (4D) digit lengths in young children using the 4D as a covariate.

METHODS

One hundred and three young children (54 boys and 49 girls) performed maximum voluntary GS and ultrasound-measured forearm muscle thickness measurements in the right hand. All participants completed the first measurement and underwent a second measurement 1 year after the first one. The 2D and 4D were taken on the palmar surface of the outstretched right hand at the second measurement.

RESULTS

The 2D was inversely associated with the change in GS (B = -2.1, p = 0.023) adjusted for all covariates. Girls had numerically lower adjusted changes in grip strength, although this was not statistically significant [-0.61 (-1.2, 0.02) kg]. When sex was removed from the model, the 2D remained inversely associated with the change in GS (B = -2.39, p = 0.011). Finally, when only adjusting for the 4D, the 2D was inversely associated with the change in GS (B = -3.07, p = 0.004).

CONCLUSION

This study documented the association between changes in GS over 1 year and digit lengths in young children. The difference in children's digit length needs to be recognized as a factor involved in weak GS in children.

One-Year Handgrip Strength Change in Kindergarteners Depends upon Physical Activity Status

Free play in kindergarten can be roughly divided into fine and gross motor activities, but the effects of these activities on improving handgrip strength are unknown. Therefore, we aimed to compare one-year changes in handgrip strength and forearm flexor muscle size in children separated by preferred play in a kindergarten. One hundred and eleven children were recruited from a local kindergarten. They underwent handgrip strength and forearm muscle thickness measurements, and 95 (49 boys and 46 girls) underwent a second measurement one year after the first measurement. Class teachers assessed the physical activity of everyone in their class after the second measurement. Using three evaluation scores by the class teachers, we divided children into three groups based on the children's preference to play in kindergarten (fine movement vs. gross motor movement). Handgrip strength did not change differently between groups across one year. However, children who liked active playing outside (i.e., gross motor activity) were stronger than others. Furthermore, children who like playing outside observed greater changes than the other groups in the ulna (right hand) and radius muscle thickness (left hand), suggesting that changes in forearm muscle size might be incongruent with changes in handgrip strength among the three activity groups.

Handgrip Strength and Healthspan: Impact of Sports During the Developmental Period on Handgrip Strength (Juntendo Fitness Plus Study)

Handgrip strength as a biomarker is being studied as a factor in predicting disease onset. However, the effect of improving handgrip strength through physical exercises, such as sports during the developmental period, on disease prevention has yet to be fully elucidated. The Juntendo Fitness Plus (J-Fit Plus) Study is a unique database of anthropometric and physical fitness measurements with over 50 years of accumulated data. It has the potential to explore the effects of sports on the association between handgrip strength and morbidity/mortality. We first outline previous studies on the impact of physical exercise interventions on handgrip strength, separated into adulthood and developmental period. We then introduced a unique effort to investigate the effects of sports using the J-Fit Plus Study database and describe the challenges of finally elucidating the impact of exercise on the association between handgrip strength and health status.

Low skeletal muscle mass index and all-cause mortality risk in adults: A systematic review and meta-analysis of prospective cohort studies

OBJECTIVE

The relationship between low skeletal muscle mass index (SMI) and all-cause mortality risk in the general adults remains unclear. Our study was conducted to examine and quantify the associations between low SMI and all-cause mortality risks.

METHODS

PubMed, Web of Science, and Cochrane Library for primary data sources and references to relevant publications retrieved until 1 April 2023. A random-effect model, subgroup analyses, meta-regression, sensitivity analysis, and publication bias were conducted using STATA 16.0.

RESULTS

Sixteen prospective studies were included in the meta-analysis of low SMI and the risk of all-cause mortality. A total of 11696 deaths were ascertained among 81358 participants during the 3 to 14.4 years follow-up. The pooled RR of all-cause mortality risk was 1.57 (95% CI, 1.25 to 1.96, P < 0.001) across the lowest to the normal muscle mass category. The results of meta-regression showed that BMI (P = 0.086) might be sources of heterogeneity between studies. Subgroup analysis showed that low SMI was significantly associated with an increased risk of all-cause mortality in studies with a body mass index (BMI) between 18.5 to 25 (1.34, 95% CI, 1.24-1.45, P<0.001), 25 to 30 (1.91, 95% CI, 1.16-3.15, P = 0.011), and over 30 (2.58, 95% CI, 1.20-5.54 P = 0.015).

CONCLUSIONS

Low SMI was significantly associated with the increased risk of all-cause mortality, and the risk of all-cause mortality associated with low SMI was higher in adults with a higher BMI. Low SMI Prevention and treatment might be significant for reducing mortality risk and promoting healthy longevity.

Association of absolute and relative hand grip strength with all-cause mortality among middle-aged and old-aged people

OBJECTIVES

This study aimed to examine the association of absolute and relative hand grip strength (HGS) with the risk of all-cause mortality among middle-aged and old-aged people in South Korea. Considering that both absolute HGS and relative HGS could be effective measures, an in-depth investigation is necessary to compare the effects of both measures on mortality.

METHODS

Data of 9,102 participants, derived from the Korean Longitudinal Study of Aging from 2006 to 2018, were examined. HGS was divided into two categories: absolute HGS and relative HGS (defined as HGS divided by body mass index). The risk of all-cause mortality was the dependent variable. Cox proportional hazard regression was used to analyze the association between HGS and all-cause mortality.

RESULTS

The average of absolute and relative HGS were 25.6 ± 8.7 kg and 1.1 ± 0.4 kg/BMI, respectively. The all-cause mortality rate decreased by 3.2% as absolute HGS increased by 1 kg (adjusted hazard ratio [HR] = 0.968, 95% CI = 0.958-0.978). An increase in relative HGS by 1 kg/BMI was associated with a 22% reduction in risk of all-cause mortality (adjusted HR = 0.780, 95% CI = 0.634-0.960). Individuals with more than two chronic diseases, there was a decrease in all-cause mortality as absolute HGS increased by 1 kg and relative HGS by 1 kg/BMI (absolute HGS; adjusted HR = 0.97, 95% CI = 0.959-0.982, relative HGS; adjusted HR = 0.483, 95% CI = 0.325-0.718).

CONCLUSIONS

Our study findings showed that both absolute and relative HGS were inversely associated with the risk of all-cause mortality; a higher absolute/relative HGS was associated with a lower risk of all-cause mortality. Moreover, these findings highlight the importance of improving HGS to alleviate the burden of adverse health problems.

Musculoskeletal Fitness for Identifying Low Physical Function in Older Women

AIMS

This cross-sectional study aimed to analyze the relevance of musculoskeletal fitness for identifying low physical functioning in community-dwelling older women.

METHODS

Sixty-six older women (73.62 ± 8.23 yrs old) performed a musculoskeletal fitness assessment of the upper and lower limbs. A handheld dynamometer was used to evaluate upper-limb muscle strength through a handgrip (HG) test. Lower-limb power and force were assessed from a two-leg countermovement vertical jump (VJ) on a ground reaction force platform. Physical functioning was assessed subjectively using the Composite Physical Function (CPF) questionnaire and objectively by daily step count measured by accelerometry and gait speed/agility assessed by the 8-Foot Up-and-Go (TUG) test. Logistic regressions and ROC curves were carried out to define odds ratios and ideal cutoff values for discriminatory variables.

RESULTS

VJ power showed the ability to identify low physical functioning when evaluated through the CPF (14 W/kg, 1011 W), gait speed/agility (15 W/kg, 800 W), or daily accumulated steps (17 W/kg). Considering that VJ power was normalized for body mass, the increase of 1 W/kg corresponds to a decrease of 21%, 19%, or 16% in the chance of low physical functioning when expressed by these variables, respectively. HG strength and VJ force did not show a capacity to identify low physical functioning.

CONCLUSIONS

The results suggest that VJ power is the only marker of low physical functioning when considering the three benchmarks: perception of physical ability, capacity for mobility, and daily mobility.

Association between Preoperative Hand Grip Strength and Postoperative Delirium after Cardiovascular Surgery: A Retrospective Study

The association of frailty with postoperative delirium has not been fully investigated in patients undergoing cardiovascular surgery. Therefore, this study aimed to investigate whether preoperative hand grip strength is associated with postoperative delirium. This retrospective study included patients aged >65 years who had undergone elective cardiovascular surgery using cardiopulmonary bypass at a Japanese university hospital between April 2020 and February 2022. We defined low hand grip strength as hand grip values of <275 n and <177 n for men and women, respectively. Postoperative delirium was assessed using the confusion assessment method during patients’ intensive care unit stay. The odds ratio of low hand grip strength for postoperative delirium was estimated using multiple logistic analysis, which was adjusted for prominent clinical factors. Ninety-five patients with a median age of 74 years were included in the final analysis, and 31.5% of them had low hand grip strength. Postoperative delirium occurred in 37% of patients, and the odds ratio of low preoperative hand grip strength for postoperative delirium was 4.58 (95% confidence interval: 1.57–13.2). Thirty-seven patients experienced postoperative delirium after cardiovascular surgery using cardiopulmonary bypass, and low preoperative hand grip strength was positively associated with its occurrence.

Athletes in sporting events with upper-body gripping movements have greater handgrip strength than those in sporting events that prioritize the lower body

OBJECTIVE

Evidence suggests that acquiring a high level of handgrip strength early in life and maintaining that strength throughout life may be important for health. In addition, it is thought that sports activities performed during the developmental period are effective in improving handgrip strength, but it is unknown what types of sports are more effective. As a first step, we conducted a cross-sectional study to compare handgrip strength across different sports (upper-body gripping sports vs. lower body) in early adulthood.

METHODS

We used the Juntendo Fitness Plus Study data from 1973 to 2018 and selected two types of sporting events with matching physiques (soccer, baseball, and kendo) but different degrees of gripping. Data on 7344 male first-year sports university students included 1127 soccer, 297 Kendo, and 698 baseball players.

RESULTS

Those in the lower body-only (soccer) sports had -3.78 (95% CI: -4.27, -3.29) kg lower handgrip strength than those in the lower + upper (kendo and baseball). Comparing each individual sport found that each sport was different from each other with Kendo > Baseball > Soccer (between each sport, p < .001). In addition, the difference between sports has become greater across time.

CONCLUSIONS

In early adulthood, handgrip strength is greatest in those participating in sports with upper-body movements compared to those participating in sports that mainly involved lower-body movements. The three sports we selected are natural activities that do not directly train handgrip strength. Therefore, sport may be one potential method to improve low handgrip strength in children/adolescents during the developmental period.

Effects of post-exercise cold-water immersion on resistance training-induced gains in muscular strength: a meta-analysis

The aim of this review was to perform a meta-analysis examining the effects of cold-water immersion (CWI) coupled with resistance training on gains in muscular strength. Four databases were searched to find relevant studies. Their methodological quality and risk of bias were evaluated using the PEDro checklist. The effects of CWI vs. control on muscular strength were examined in a random-effects meta-analysis. Ten studies (n = 170; 92% males), with 11 comparisons across 22 groups, were included in the analysis. Studies were classified as of good or fair methodological quality. The main meta-analysis found that CWI attenuated muscular strength gains (effect size [ES]: -0.23; 95% confidence interval [CI]: -0.45, -0.01; p = 0.041). In the analysis of data from studies applying CWI only to the trained limbs, CWI attenuated muscular strength gains (ES: -0.31; 95% CI: -0.61, -0.01; p = 0.041). In the analysis of data from studies using whole-body CWI, there was no significant difference in muscular strength gains between CWI and control (ES: -0.08; 95% CI: -0.53, 0.38; p = 0.743). In summary, this meta-analysis found that the use of CWI following resistance exercise sessions attenuates muscular strength gains in males. However, when CWI was applied to the whole body, there was no significant difference between CWI and control for muscular strength. Due to the attenuated gains in muscular strength found with single limb CWI, the use and/or timing of CWI in resistance training should be carefully considered and individualized.

Children with Low Handgrip Strength: A Narrative Review of Possible Exercise Strategies to Improve Its Development

BACKGROUND

Handgrip strength (HGS) is a predictor of health in both children and adults. Evidence suggests that without a possible strategy, children with low HGS may become adults with low HGS. However, little is known about what strategies are effective for children with low HGS to achieve a higher baseline level in adulthood. This narrative review aimed to investigate whether physical exercise interventions could improve HGS in children.

METHODS

The relevant databases/search engine was searched using keywords related to the main topics discussed throughout this review.

RESULTS

Our findings suggest that it may not be possible to improve HGS over that observed from normal development with physical education or traditional resistance-training programs. However, if the training program includes exercises that directly stimulate the forearm/hand muscle groups to grip, it may be possible to obtain changes in HGS that exceed the changes due to normal developmental growth.

CONCLUSION

Although there are associations between HGS and markers of health, no research could be identified that examined whether increasing HGS would lead to an improvement in health. If an increase in HGS really does represent an improvement in long-term health, then gripping exercise may need to be included into physical activity programs during the growth/development phase.

Physical and psychological reconditioning in long COVID syndrome: Results of an out-of-hospital exercise and psychological - based rehabilitation program

Background

Long Covid Syndrome (LCS) is used to describe signs and symptoms that continue or develop after acute COVID-19 infection. Natural history and treatment of this syndrome are still poorly understood, even if evidences suggest the potential role of physical rehabilitation in improving symptoms in these patients.

Aim of the study

The aim of the present study was to evaluate effectiveness, safety and feasibility of an out-of-hospital multidisciplinary rehabilitation (MDR) program, based both on physical and psychological reconditioning, in reducing symptoms and improving physical fitness and psychological parameters in patients with LCS.

Methods

Thirty consecutive patients with LCS (18 males, mean age 58 years) underwent an accurate medical screening process including anthropometric and muscular strength evaluation, cardiopulmonary exercise test, quality of life (QoL) and psychological appraisal before and after a MDR program.

Results

At baseline, all LCS patients were strongly symptomatic and showed severe impairments in physical performance, QoL and psychological parameters. No adverse effects and dropouts were observed during the exercise training sessions. After the MDR program, COVID-19 residual symptoms significantly decreased, and significant improvements in upper and lower limb muscular strength, cardiopulmonary parameters, perceived physical and mental health, depression and anxiety were observed.

Conclusions

The present study confirms the severe physical and psychological impairment of patients with LCS and suggests that a MDR program is effective, safe and feasible in these patients and could promote their physical and psychological recovery.

Muscular strength and skeletal muscle mass in 511 physically independent older women aged 60-88 years

Although one-repetition maximum (1RM) and lean soft tissue (LST) are the most common measures to assess muscular strength and skeletal muscle mass in older adults, reference data is still missing. Therefore, the present study aimed to produce reference values for the 1RM tests and LST in physically independent older women. Furthermore, the effect of age and body segment on these outcomes was examined. Five hundred and eleven older women aged 60-88 years participated in the present study. The 1RM tests were performed on chest press, leg extension, and preacher curl exercises. Dual-energy X-ray absorptiometry exams were used to determine total and segmental LST. The 1RM and LST average values: chest press = 44.0 ± 11.1 kg, leg extension = 48.8 ± 11.8 kg, preacher curl = 21.6 ± 5.4 kg; trunk LST = 19.0 ± 2.7 kg, lower-limbs LST = 12.5 ± 1.9 kg, upper-limbs LST = 4.0 ± 0.7 kg, appendicular LST = 16.6 ± 2.6, total LST = 38.5 ± 5.2 kg. The age-related declines in 1RM chest press and leg extension were higher than in preacher curl. The present study provides reference values for 1RM of different body segments and total and segmental LST in older women. In addition, our results revealed a reduction of muscular strength and LST with increasing age, and the magnitude of the age-related strength reduction depends on the body segment analyzed.

Weak Hand Grip Strength Is Associated with Alexithymia in Outpatients in a Mexican Population

Hand grip strength has been considered as a possible marker for metabolic and psychiatric disease. To date, however, no research has focused on the association between alexithymia and hand grip strength. The objective of the present study was to investigate the correct association between hand grip strength and alexithymia. A cross-sectional study was carried out in Comalcalco, Tabasco, México. A total of 246 individuals were included. Hand grip strength was evaluated in the dominant hand using a Takei^® portable digital dynamometer. Alexithymia was measured using the Toronto Alexithymia Scale (TAS-20). Two linear regression models adjusted by confounders were used to determine the association between alexithymia and hand grip strength. The rate for positive alexithymia was 39.0% (n = 94). Individuals with alexithymia showed a weaker hand grip strength than the comparison group (t = 2.4, 244 df, p = 0.01). Individuals with alexithymia had significantly reduced levels of hand grip strength (β = −0.39 ± 0.14; p = 0.006); after additional adjustment for clinical variables, decreased hand grip strength remained (β = 8.00 ± 1.86; p ≤ 0.001). Our results suggest that a decrease in hand grip strength could be associated with alexithymia. This measurement could be useful as a predictive marker for the identification of alexithymia in Mexican individuals who attend outpatient clinics.

Absolute and relative grip strength as predictors of cancer: prospective cohort study of 445 552 participants in UK Biobank

BACKGROUND

Reduced muscular strength, as measured by absolute grip strength, has been associated with increased risk of some site-specific cancers. The ability of grip strength to predict other diseases may be affected by whether it is expressed in absolute or relative terms, but the evidence for cancer is scarce. This study compared the associations of absolute and relative grip strength with all-cause and 15 site-specific cancers.

METHODS

A prospective cohort study was undertaken using data from the UK Biobank. The exposure variable was grip strength, in absolute form (kilogrammes) and relative to weight, body mass index (BMI), height. and body fat mass. The outcome was incident cancer, at 15 sites and overall. Cox proportional hazard models were performed to study the associations.

RESULTS

This study included 445 552 participants, where 53.8% of the participants were women, with a mean (SD) age of 56.3 (8.11) years. During a median of 8.8 years follow-up period, 48 886 (11.0%) patients were diagnosed with cancer. After adjusting for sociodemographic and lifestyle factors, as well as multiple testing, absolute grip strength was inversely and linearly associated with endometrial [hazard ratio (HR): 0.74, 95% confidence interval (CI): 0.69; 0.79, P value <0.001], gallbladder (HR: 0.81, 95% CI: 0.72; 0.92, P value = 0.001), liver (HR: 0.86, 95% CI: 0.79; 0.93, P value <0.001), kidney (HR: 0.93, 95% CI: 0.88; 0.99), and breast (HR: 0.93, 95% CI: 0.91; 0.96, P value = 0.031), as well as all-cause cancer (HR: 0.97, 95% CI: 0.95; 0.98, P value <0.001). Eight cancer sites were inversely associated with HGS relative to weight and BMI: endometrium, liver, gallbladder, kidney, oesophagus, pancreas, colorectal, breast, and all-cause cancer. Compared with absolute grip strength, grip strength relative to body fat mass had better discriminatory power for head and neck and breast cancer. Grip strength relative to BMI was marginally better than absolute grip strength in predicting stomach cancer.

CONCLUSIONS

Grip strength was associated with risk of several site-specific cancers and all-cause cancer. Head and neck and breast cancers might be better predicted by relative grip strength.

Associations Between Relative Grip Strength and the Risk of 15 Cancer Sites

INTRODUCTION

Grip strength is the most commonly used muscle strength proxy in clinical research. However, evidence regarding the associations of grip strength with cancer has been mainly restricted to overall cancer risk. Therefore, this study aims to evaluate the associations between grip strength relative to BMI and 15 cancer sites as well as with all-cause cancer mortality.

METHODS

A total of 445,555 participants (53.8% women, mean age=56.3 years) were recruited across the United Kingdom. The association of grip strength relative to BMI (expressed as 1 SD) with incidence and mortality from 15 cancer sites was investigated using Cox proportional hazard models. All analyses were conducted in April 2021.

RESULTS

Over an 8.8-year follow-up period, 37,291 patients were diagnosed with cancer, and 11,363 died of it. After covariate adjustment, higher relative grip strength per 1 SD was associated with a lower risk of incident endometrial (hazard ratio=0.76, 95% CI=0.71, 0.81), liver (hazard ratio=0.81, 95% CI=0.74, 0.88), gallbladder (hazard ratio=0.83, 95% CI=0.73, 0.94), kidney (hazard ratio=0.89, 95% CI=0.84, 0.95), and colorectal (hazard ratio=0.94, 95% CI=0.91, 0.98) cancer as well as with lower risk of gallbladder, colorectal, endometrial, liver, and all-cause cancer mortality.

CONCLUSIONS

Grip strength relative to BMI was associated with incidence and mortality from endometrial, gallbladder, colorectal, liver, all-cause cancer, and breast and kidney cancer incidence, independent of major confounding factors, including comorbidity, diet, and physical activity.

Association between grip strength and anthropometric characteristics in the community-dwelling elderly population in Taiwan

BACKGROUND

Sarcopenia and muscle weakness in elderly are contributed burden of public health and impact on quality of life. Weak grip strength was key role in diagnosis of sarcopenia and reported increased mortality, function declined in elderly. This study evaluated the association between GS and each common anthropometric characteristic in community-dwelling elderly.

DESIGN AND METHOD

From 2017 to 2019, we conducted a community-based health survey among the elderly in Chiayi county, Taiwan. Participants were 65 years old or older, and total of 3,739 elderly subjects (1,600 males and 2,139 females) with a mean age of 76 years (range 65-85 years old) were recruited. General demographic data and lifestyle patterns were measured using a standard questionnaire. Anthropometric characteristics such as body height, body weight, body mass index (BMI), body waist and hip circumference, and body fat were measured by standard methods. GS was measured using a digital dynamometers (TKK5101) method.

RESULTS

The mean GS was 32.8 ± 7.1 kg for males and 21.6 ± 4.8 kg for females (p < 0.001). For both sexes, elderly subjects with the same body weight but smaller body waist circumference had greater GS. The subjects with the same body waist size but heavier weight had greater GS. Furthermore, after adjusting for age, lifestyles, disease status, and potential anthropometric variable, multivariate regression analyses indicated that BMI was positively associated with GS (for males, beta = 0.310 and for females beta = 0.143, both p < 0.001) and body waist was negatively associated with GS (for males, beta = -0.108, p < 0.001; for females, beta = -0.030, p = 0.061).

CONCLUSIONS

This study suggested that old adults with higher waist circumstance had weaker GS. Waist circumstance was negatively associated with GS, body weight was positively associated with GS in contrast. It may implies that central obesity was more important than overweight for GS in elderly.

Associations between grip strength and incident type 2 diabetes: findings from the UK Biobank prospective cohort study

INTRODUCTION

Grip strength has been associated with chronic diseases and mortality. However, current evidence of the association between grip strength and incident type 2 diabetes mellitus (T2DM) is controversial. The aim of this study was to investigate the associations of absolute and relative grip strength with incident T2DM and whether these associations differ by sociodemographic, lifestyle and adiposity-related factors.

RESEARCH DESIGN AND METHODS

This was a prospective cohort study of 166 894 participants in the UK Biobank (mean age 56.5 years, 54.4% women). The outcome was T2DM incidence and the exposure was grip strength, expressed in absolute (kg) and relative (kg per kg of body weight) values. The association between grip strength and T2DM incidence was investigated using Cox-proportional regression.

RESULTS

The median follow-up was 5.3 years (IQR: 4.7-6.1). During this time, 3713 participants developed T2DM. Lower grip strength was associated with a higher risk of T2DM in both sexes. Those in the lowest quintile of absolute grip strength had a 50% higher risk in men (HR: 1.50 (95% CI: 1.30 to 1.73)) and 25% higher risk in women (HR: 1.25 (95% CI: 1.06 to 1.47)) compared with those in the highest quintile. For relative grip strength, risk of diabetes was more than double for men (HR: 2.22 (95% CI: 1.84 to 2.67)) and 96% higher for women (HR: 1.96 (95% CI: 1.52 to 2.53)) in the lowest compared with highest quintiles.

CONCLUSIONS

Grip strength is associated with a higher risk of T2DM incidence in both men and women independent of important confounding factors including age, deprivation, adiposity and lifestyle. However, the associations were stronger when grip strength is expressed relative to body weight, which could reflect the importance of muscle quality.

Comparison of risk factors between people with type 2 diabetes and matched controls in Nairobi, Kenya

OBJECTIVE

To identify risk factors associated with type 2 diabetes (T2D) in Nairobi, Kenya.

METHODS

A case-control study comparing 70 (53% women) recently diagnosed T2D cases with age-, sex- and socioeconomic status-matched normoglycemic controls (1:1). Objectively measured data were obtained on anthropometrics, handgrip strength and physical activity (by accelerometer). Self-reported data were collected on demographic characteristics and lifestyle factors. Logistic regression models, adjusted for covariates, were used to analyse the data.

RESULTS

Each standard deviation (SD) increase in height was associated with lower odds for T2D (adjusted odds ratio (AOR) = 0.34 (95% confidence intervals [CIs] 0.17, 0.66), P = 0.0031). Fat-free mass was inversely associated with T2D (AOR = 0.42 (95% CI 0.24, 0.75), P = 0.0032, per SD increase). Grip strength was associated with a lower risk of T2D (AOR = 0.20 (95% CI 0.08, 0.45), P < 0.001, per SD increase). BMI was not associated with T2D, but higher waist-to-hip ratio was associated higher odds of T2D (AOR = 2.28 (95% CI 1.38, 3.79), P = 0.0014, per SD increase). Physical activity was not associated with T2D. Cases reported higher intakes of fruits and vegetables and a lower intake of sugar than controls.

CONCLUSIONS

Central obesity, rather than BMI, may have more utility for T2D risk stratification in Kenya, and interventions that increase muscle mass and strength, as well as support weight loss, may be useful for T2D prevention in this and other SSA populations. However, more evidence is needed to determine whether low muscle mass, strength and height are causally related to T2D risk and/or are indicators of adverse early-life environment.

Handgrip strength and health outcomes: Umbrella review of systematic reviews with meta-analyses of observational studies

PURPOSE

The aim of the present study was to assess both the credibility and strength of evidence arising from systematic reviews with meta-analyses of observational studies on handgrip strength and health outcomes.

METHODS

An umbrella review of systematic reviews with meta-analyses of observational studies was conducted. We assessed meta-analyses of observational studies based on random-effect summary effect sizes and their p values, 95% prediction intervals, heterogeneity, small-study effects, and excess significance. We graded the evidence from convincing (Class I) to weak (Class IV).

RESULTS

From 504 articles returned in a search of the literature, 8 systematic reviews were included in our review, with a total of 11 outcomes. Overall, nine of the 11 of the outcomes reported nominally significant summary results (p < 0.05), with 4 associations surviving the application of the more stringent p value (p < 10^-6). No outcome presented convincing evidence. Three associations showed Class II evidence (i.e., highly suggestive): (1) higher handgrip values at baseline were associated with a minor reduction in mortality risk in the general population (n = 34 studies; sample size = 1,855,817; relative risk = 0.72, 95% confidence interval (95%CI): 0.67-0.78), (2) cardiovascular death risk in mixed populations (n = 15 studies; relative risk = 0.84, 95%CI: 0.78-0.91), and (3) incidence of disability (n = 7 studies; relative risk = 0.76, 95%CI: 0.66-0.87).

CONCLUSION

The present results show that handgrip strength is a useful indicator for general health status and specifically for early all-cause and cardiovascular mortality, as well as disability. To further inform intervention strategies, future research is now required to fully understand mechanisms linking handgrip strength scores to these health outcomes.

Effects of Resistance Training on Muscle Size and Strength in Very Elderly Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Effects of resistance training on muscle strength and hypertrophy are well established in adults and younger elderly. However, less is currently known about these effects in the very elderly (i.e., 75 years of age and older).

OBJECTIVE

To examine the effects of resistance training on muscle size and strength in very elderly individuals.

METHODS

Randomized controlled studies that explored the effects of resistance training in very elderly on muscle strength, handgrip strength, whole-muscle hypertrophy, and/or muscle fiber hypertrophy were included in the review. Meta-analyses of effect sizes (ESs) were used to analyze the data.

RESULTS

Twenty-two studies were included in the review. The meta-analysis found a significant effect of resistance training on muscle strength in the very elderly [difference in ES = 0.97; 95% confidence interval (CI) 0.50, 1.44; p = 0.001]. In a subgroup analysis that included only the oldest-old participants (80 + years of age), there was a significant effect of resistance training on muscle strength (difference in ES = 1.28; 95% CI 0.28, 2.29; p = 0.020). For handgrip strength, we found no significant difference between resistance training and control groups (difference in ES = 0.26; 95% CI - 0.02, 0.54; p = 0.064). For whole-muscle hypertrophy, there was a significant effect of resistance training in the very elderly (difference in ES = 0 30; 95% CI 0.10, 0.50; p = 0.013). We found no significant difference in muscle fiber hypertrophy between resistance training and control groups (difference in ES = 0.33; 95% CI - 0.67, 1.33; p = 0.266). There were minimal reports of adverse events associated with the training programs in the included studies.

CONCLUSIONS

We found that very elderly can increase muscle strength and muscle size by participating in resistance training programs. Resistance training was found to be an effective way to improve muscle strength even among the oldest-old.

Does resistance training promote enough muscular strength increases to move weak older women to better strength categories?

We compared the magnitude of muscular strength changes among older women occupants of different strength tertiles in response to progressive resistance-training (RT). Additionally, we examined the possibility of older women initially characterized as weak (occupants of the lower tertile of strength status) can achieve a higher muscular strength level to be inserted into a better category (middle or upper tertiles). The present investigation was attended by 113 physically independent older women (>60 years old). Muscular strength was assessed by one-repetition maximum (1RM) tests on chest press, preacher curl, leg extension exercises, and by the isokinetic (ISOK) peak torque of knee extension and flexion at 60 and 180°/s angular velocities. The RT lasted 12 weeks (3 x/week) and consisted of eight exercises for the whole body. The participants were divided into tertiles (LOWER, MIDDLE, and UPPER) according to the performance at baseline for each strength measure. After RT, the LOWER tertile showed more significant magnitude gains than the UPPER tertile to the 1RM in leg extension and preacher curl and isokinetic measurements (6.9-36.3%). A considerable number of older women increased muscular strength enough to move from LOWER to MIDDLE or UPPER tertiles. From our results, it can be inferred that older women occupants of the lower strength tertile show more significant muscular strength gains when compared to their stronger counterparts. Moreover, 12 weeks of RT seem to be sufficient to transfer older women previously characterized as "weak" to a better category.

Cortical hemodynamics as a function of handgrip strength and cognitive performance: a cross-sectional fNIRS study in younger adults

BACKGROUND

There is growing evidence for a positive correlation between measures of muscular strength and cognitive abilities. However, the neurophysiological correlates of this relationship are not well understood so far. The aim of this study was to investigate cortical hemodynamics [i.e., changes in concentrations of oxygenated (oxyHb) and deoxygenated hemoglobin (deoxyHb)] as a possible link between measures of muscular strength and cognitive performance.

METHODS

In a cohort of younger adults (n = 39, 18-30 years), we assessed (i) handgrip strength by a handhold dynamometer, (ii) short-term working memory performance by using error rates and reaction times in the Sternberg task, and (iii) cortical hemodynamics of the prefrontal cortex (PFC) via functional near-infrared spectroscopy (fNIRS).

RESULTS

We observed low to moderate negative correlations (rp =  ~ - 0.38 to - 0.51; p < 0.05) between reaction time and levels of oxyHb in specific parts of the PFC. Furthermore, we noticed low to moderate positive correlations (rp =  ~ 0.34 to 0.45; p < 0.05) between reaction times and levels of deoxyHb in distinct parts of the PFC. Additionally, higher levels of oxyHb (rp (35) = 0.401; p = 0.014) and lower levels of deoxyHb (rp (34) = - 0.338; p = 0.043) in specific parts of the PFC were linked to higher percentage of correct answers. We also found low to moderate correlations (p < 0.05) between measures of handgrip strength and levels of oxyHb (rp =  ~ 0.35; p < 0.05) and levels of deoxyHb (rp =  ~ - 0.25 to - 0.49; p < 0.05) in specific parts of the PFC. However, there was neither a correlation between cognitive performance and handgrip strength nor did cortical hemodynamics in the PFC mediate the relationship between handgrip strength and cognitive performance (p > 0.05).

CONCLUSION

The present study provides evidence for a positive neurobehavioral relationship between cortical hemodynamics and cognitive performance. Our findings further imply that in younger adults higher levels of handgrip strength positively influence cortical hemodynamics although the latter did not necessarily culminate in better cognitive performance. Future research should examine whether the present findings can be generalized to other cohorts (e.g., older adults).

Resistance training leads to large improvements in strength and moderate improvements in physical function in adults who are overweight or obese: a systematic review

QUESTIONS

What are the effects of resistance training on muscle strength, physical function and muscle power in adults who are overweight or obese? Which factors moderate the effects?

DESIGN

Systematic review of randomised controlled trials, with random effects meta-analyses and meta-regressions.

PARTICIPANTS

Adults who are overweight or obese.

INTERVENTION

Resistance training lasting ≥ 4 weeks.

OUTCOME MEASURES

Muscle strength, muscle power and physical function.

RESULTS

Thirty trials with 1,416 participants met the eligibility criteria. Pooled analyses indicated that resistance training has a large beneficial effect on muscle strength (SMD 1.39, 95% CI 1.05 to 1.73, I² = 85%) and a moderate effect on physical function (SMD 0.67, 95% CI 0.25 to 1.08, I² = 71%) in adults who are overweight or obese. However, the effect of resistance training on muscle power was unclear (SMD 0.42, 95% CI -3.3 to 4.2, I² = 46%). The effect of resistance training on strength was greatest for the upper body (versus lower/whole body: β = 0.35, 95% CI 0.05 to 0.66) and in dynamic strength tests (versus isometric/isokinetic: β = 1.20, 95% CI 0.60 to 1.81), although trials judged to have good methodological quality reported statistically smaller effects (versus poor/fair quality: β = -1.21, 95% CI -2.35 to -0.07). Concomitant calorie restriction did not modify strength gains but reduced the effect of resistance training on physical function (β = -0.79, 95% CI -1.41 to -0.17). Small study effects were evident for strength outcomes (β = 5.9, p < 0.001).

CONCLUSIONS

Resistance training has a large positive effect on muscle strength and a moderate effect on physical function in adults who are overweight or obese. However, the effect of resistance training on muscle power is uncertain. In addition, concomitant calorie restriction may compromise the functional adaptations to resistance training.

REGISTRATION

PROSPERO CRD42019146394.

Comparative Effects of High-Intensity Interval Training vs Moderate-Intensity Continuous Training in Phase III of a Tennis-Based Cardiac Rehabilitation Program: A Pilot Randomized Controlled Trial

The aim of the present study was to investigate the effects of two tennis-based cardiac rehabilitation programs using two protocols: high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) in the body composition, physical fitness, heart rate variability, and health-related quality of life. It was performed as a single-blinded randomized controlled trial of 21 people with acute coronary syndrome. The 12-week cardiac rehabilitation program consisted of three sessions per week of 60 min with the main part consisting of 10 sets of 15 s with 15 s of active recovery at 85%–90% of their maximum heart rate or 40 min at 70%–85% of their maximum heart rate in the HIIT and the MICT groups, respectively. Results show that both cardiac rehabilitation programs improved the agility and the mental components of the health-related quality of life (p-value < 0.05). The HIIT protocol also showed a significant improvement in the flexibility of upper and lower limbs (p-value < 0.05). Moreover, significant group × time interaction was found in the handgrip strength in favor of the HIIT group (p-value = 0.035). Nevertheless, no significant effects on cardiorespiratory fitness or heart rate variability were found. Importantly, no adverse event was detected, so HIIT appears to be a safe and effective alternative for the rehabilitation of patients with acute coronary syndrome.

Influence of Handgrip Stabilization During Isokinetic Knee Strength Assessment in Older Women

The present study aimed to evaluate the influence of holding the chair handles during the assessment of older women's knee flexion and extension isokinetic and isometric strength. Of 57 older women (≥60 years) selected from a convenience sample for this research, 23 were randomly chosen to perform the tests twice for reliability analyses. Each participant performed maximal isokinetic knee extension and flexion at 60°/s and 180°/s angular velocities and isometric tests under two conditions: (a) holding the lateral handle of the chair (HOLD) and (b) supporting the hands on the shoulders with the arms crossed (i.e., not holding the handle [NHOLD]). Participants performed significantly better in the HOLD compared with the NHOLD condition. Slightly lower intraclass correlation coefficients (ICC = 0.870-0.956) were noted for the HOLD than for the NHOLD condition (ICC = 0.900-0.981) so that the HOLD performance on Days 1 and 2 was different on some measures. Owing to the higher reliability coefficients in the NHOLD condition, results suggest that, when assessing knee strength in older women, the evaluee should place their hands over their shoulders with arms crossed in front of the chest (NHOLD) to maximize assessment reliability (reproducibility of performance).

What are the association patterns between handgrip strength and adverse health conditions? A topical review

Measures of handgrip strength can be used to conveniently assess overall muscle strength capacity. Although stand-alone measures of handgrip strength provide robust health information, the clinical meaningfulness to determine prevention and treatment options for weakness remains limited because the etiology of muscle weakness remains unclear. Moreover, clinical outcomes associated with handgrip strength are wide-ranging. Therefore, disentangling how handgrip strength is associated with health conditions that are metabolically or neurologically driven may improve our understanding of the factors linked to handgrip strength. The purpose of this topical review was to highlight and summarize evidence examining the associations of handgrip strength with certain health outcomes that are metabolically and neurologically driven. From this perusal of the literature, we posit that stand-alone handgrip strength be considered an umbrella assessment of the body systems that contribute to strength capacity, and a panoptic measurement of muscle strength that is representative of overall health status, not a specific health condition. Recommendations for future strength capacity–related research are also provided.

Handedness, Grip Strength, and Memory Function: Considerations by Biological Sex

Background and Objective: The objective of this study was to evaluate the potential independent and interactive effects of handedness and grip strength on episodic memory function, and whether biological sex moderated these relationships. Materials and Methods: 162 young adults (Mage = 20.7 years) completed a series of memory assessments including a subjective memory complaint evaluation and several objective measures of memory. Handedness (i.e., left-hand dominant, inconsistent handedness (ICH), and right-hand dominant) was evaluated using the Edinburgh Handedness Inventory. Handgrip strength was determined from a handgrip dynamometer. Results: When compared to ICH individuals, retrospective memory scores were statistically significantly worse for left-handed (p = 0.02) and right-handed (p = 0.03) individuals. Higher grip strength was statistically significantly associated with fewer retrospective memory complaints (b = 0.10, 95% CI: 0.01, 0.19, p = 0.04). Conclusions: The present study provides some suggestive evidence that ICH (inconsistent handedness) and greater grip strength are associated with fewer retrospective memory complaints. However, we did not observe any evidence of an interaction effect of handedness and grip strength on memory, and similarly, biological sex did not interact with these parameters to influence memory.