Reference Values of Grip Strength, Prevalence of Low Grip Strength, and Factors Affecting Grip Strength Values in Chinese Adults

Associations of childhood socioeconomic position and health with trajectories of grip strength from middle to older ages in populations from China and England

BACKGROUND

We investigated associations of childhood socioeconomic position and health with trajectories of grip strength from middle to older ages in two distinct populations.

METHODS

We used data from the China Health and Retirement Longitudinal Study (CHARLS, n = 16,701) and English Longitudinal Study of Ageing (ELSA, n = 12,695). Hand grip strength was measured at three timepoints in CHARLS (2011-2015) and four in ELSA (2001-2020). Random-effects growth models were applied to assess associations between each childhood factor and age trajectories of grip strength.

FINDINGS

Lower parental education was associated with weaker grip strength, by 0·36 kg(95 % CI:0·17,0·56) for participants of illiterate (vs literate) parents in CHARLS and 1·88 kg(0·43,3·33) for participants of parents without education (vs ≥ high school) in ELSA, after adjusting for parental occupation and own adult socioeconomic position. Low parental occupation was associated with weaker grip strength, although the difference diminished after adjustment for adult socioeconomic position. Financial hardship was associated with weaker grip strength only in CHARLS, by 0·19 kg(0·01,0·38) after adjustment. Self-rated poor childhood health and school absenteeism were associated with weaker grip strength (both studies). Being confined to bed and hospitalised for more than a month due to health were associated with weaker grip strength only in CHARLS. Each additional childhood illness (only reported in ELSA) was associated with 0·52 kg(0·28,0·81) lower mean grip strength. Reported poor childhood health (CHARLS), low parental education and school absenteeism (ELSA) were associated with grip strength decline.

INTERPRETATION

Lower socioeconomic position and poor health in childhood were associated with weaker grip strength in later life in both Chinese and English populations. Addressing socioeconomic disparities and promoting health of children may enhance life-course physical capacity, promote healthy ageing and reduce age-related adversities.

The effect of a pre-operative and post-operative exercise programme versus standard care on physical fitness of patients with oesophageal and gastric cancer undergoing neoadjuvant treatment prior to surgery (the PERIOP-OG trial): a randomized controlled trial

INTRODUCTION

Although the benefits of post-operative rehabilitation in cancer surgery are well established, the role of prehabilitation is less defined. Oesophagogastric cancers present a unique opportunity to study the impact of prehabilitation during the neoadjuvant window, whether with chemotherapy or chemoradiotherapy (NCT) in patients who are frequently nutritionally depleted. This trial examines the impact of a community-based exercise programme on patient fitness during and after the neoadjuvant window.

METHODS

A pragmatic, randomized controlled multicentre trial was undertaken in three centres. Inclusion criteria were patients aged at least 18 years planned for NCT and esophagectomy or gastrectomy. Participants were randomized 1:1 to an exercise prehabilitation group (EX) or to usual care (UC). The primary endpoint was cardiorespiratory fitness between baseline and pre-surgery time point using the 6-minute walk test (MVT). Secondary endpoints included a hand dynamometer, 10-s sit-to-stand, activity behaviour, body mass index, semi-structured interviews, questionnaires assessing the quality of life, surgical fear, general self-efficacy and mastery.

RESULTS

Between March 2019 and December 2020, 71 participants were recruited: EX ( n =36) or UC ( n =35). From baseline to pre-surgery, the difference-in-difference (DID) for EX showed a significant improvement in 6MWT of 50.7 m ( P =0.05) compared to UC [mean (SD): 522.1 m (+/-104.3) to 582.1 m (+/-108) vs. 497.5 m (+/-106.3) to 506.0 m (+/-140.4). There was no statistically significant DID for secondary outcome measures.

CONCLUSIONS

This community exercise prehabilitation programme significantly improves physical fitness for surgery, is feasible and provides a standardized framework for the prescription of exercise in oesophagogastric cancer patients undergoing NCT.

Population-specific equations of age-related maximum handgrip force: a comprehensive review

Background

The measurement of handgrip force responses is important in many aspects, for example: to complement neurological assessments, to investigate the contribution of muscle mass in predicting functional outcomes, in setting realistic treatment goals, evaluating rehabilitation strategies. Normative data about handgrip force can assist the therapist in interpreting a patient's results compared with healthy individuals of the same age and gender and can serve as key decision criteria. In this context, establishing normative values of handgrip strength is crucial. Hence, the aim of the this study is to develop a tool that could be used both in rehabilitation and in the prevention of work-related musculoskeletal disorders. This tool takes the form of population-specific predictive equations, which express maximum handgrip force as a function of age.

Methodology

In order to collect data from studies measuring maximum handgrip force, three databases were searched. The search yielded 5,058 articles. Upon the removal of duplicates, the screening of abstracts and the full-text review of potentially relevant articles, 143 publications which focussed on experimental studies on various age groups were considered as fulfilling the eligibility criteria. A comprehensive literature review produced 1,276 mean values of maximum handgrip force.

Results

A meta-analysis resulted in gender- and world region-specific (general population, USA, Europe and Asia) equations expressing maximum force as a function of age. The equations showed quantitative differences and trends in maximum handgrip force among age, gender and national groups. They also showed that values of maximum handgrip force are about 40% higher for males than for females and that age-induced decrease in force differs between males and females, with a proved 35% difference between the ages of 35 and 75. The difference was lowest for the 60-64 year olds and highest for the 18-25 year-olds. The equations also showed that differences due to region are smaller than those due to age or gender.

Conclusions

The equations that were developed for this study can be beneficial in setting population-specific thresholds for rehabilitation programmes and workstation exposure. They can also contribute to the modification of commonly used methods for assessing musculoskeletal load and work-related risk of developing musculoskeletal disorders by scaling their limit values.

Effects of Wrist Stability Training Combined with Grip Strength Exercise on Pain and Function in Patients with Nonspecific Chronic Wrist Pain

Background and Objectives: Non-specific chronic wrist pain is wrist pain that occurs without a specific cause, such as trauma, and may limit the range of motion of the joints of the wrist and hand, affecting muscle strength, grip strength, and function. This study aimed to determine the effects of grip-strengthening exercises combined with wrist stability training on pain and function in patients with non-specific chronic wrist pain. Materials and Methods: The subjects of the study were 31 patients with wrist pain. To determine the effect of grip-strengthening exercises combined with wrist stability training, 15 participants participated in grip-strengthening exercises combined with wrist stability training and 16 control subjects participated. The experimental group participated in wrist-stability training. Grip-strengthening exercises combined with wrist stability training were performed for 20 min/day twice a week for 4 weeks, and relaxation massage and conservative physical therapy were performed for 20 min/day twice a week for 4 weeks. The control group received relaxation massage and conservative physical therapy for 40 min/day twice a week for 4 weeks. A visual pain scale was used to evaluate the degree of pain before and after treatment, and a patient-rated wrist evaluation was used to evaluate wrist function. Results: The results showed that the visual score significantly decreased in the time effect before and after the intervention in both groups (p < 0.001), patient-rated wrist evaluation significantly decreased (p < 0.001), and grip strength and muscle strength significantly increased (p < 0.001). The results of this study showed that grip-strengthening exercises combined with wrist stability training were effective in improving pain, function, grip strength, and muscle strength in patients with non-specific chronic wrist pain. Conclusions: Grip-strengthening exercises combined with wrist stability training can be used as an effective intervention method to improve pain, function, grip strength, and muscle strength, emphasizing the need for wrist exercise interventions in patients with non-specific chronic wrist pain in the future.

Cross-cultural perception of strength, attractiveness, aggressiveness and helpfulness of Maasai male faces calibrated to handgrip strength

Previous research has demonstrated that Maasai and Europeans tend to align in their ratings of the physical strength and aggressiveness of Maasai male faces, calibrated to hand grip strength (HGS). However, perceptions of attractiveness of these faces differed among populations. In this study, three morphs of young Maasai men created by means of geometric morphometrics, and depicting the average sample and two extrema (± 4 SD of HGS), were assessed by men and women from Tanzania, Czech Republic, Russia, Pakistan, China, and Mexico (total sample = 1540). The aim of this study was to test cross-cultural differences in the perception of young Maasai men's composites calibrated to HGS, focusing on four traits: physical strength, attractiveness, aggressiveness, and helpfulness. Individuals from all six cultures were able to distinguish between low, medium, and high HGS portraits. Across all study populations, portrait of Maasai men with lower HGS was perceived as less attractive, more aggressive, and less helpful. This suggests that people from diverse populations share similar perceptions of physical strength based on facial shape, as well as attribute similar social qualities like aggressiveness and helpfulness to these facial images. Participants from all samples rated the composite image of weak Maasai men as the least attractive.

The effects of back extensor strength in different body positions on health-related quality of life in patients with degenerative spinal deformity

BACKGROUND

Degenerative spinal deformity (DSD) is believed to originate from degeneration of the discs and facet joints and vertebral wedging. Currently, the nosogeny of DSD is not yet fully clarified and there has been no systematic study on the impact of their lower back muscle strength on quality of life.

OBJECTIVE

To determine the characteristics of back extensor strength (BES) in different body positions and examine their correlations with health-related quality of life (HQOL) in degenerative spinal deformity (DSD) patients.

METHODS

Participants comprised 60 DSD patients and 40 healthy volunteers. Maximal isometric BES was evaluated by dynamometers with the subject in three different positions (standing, prone, sitting). The visual analogue scale (VAS) score, Oswestry Disability Index (ODI), Roland-Morris Disability Questionnaire (RMQ), and 36-item Short Form Health Survey (SF-36) score were used to evaluate patient HQOL. Correlations between the BES in different body positions and HQOL were analysed.

RESULTS

The BES values in three body positions were significantly smaller in DSD patients than healthy subjects (P< 0.05). The standing BES was found to be negatively associated with ODI and RMQ (R= 0.313, p< 0.05 and R= 0.422, p< 0.01, respectively). A negative relationship between sitting BES and RMQ was also seen (R= 0.271, p< 0.05). In addition, the standing and prone BES were positively correlated with the physical functioning score of the SF-36 (R= 0.471, p< 0.01 and R= 0.289, p< 0.05, respectively), and the sitting BES was positively correlated with the role-physical score of the SF-36 (R= 0.436, p< 0.01).

CONCLUSION

The results indicate that the back extensor muscle is compromised in DSD patients and there are differences in predicting the severity of disability and physical HQOL scores with BES in different positions. Standing BES was the most reliable contributor to HQOL among three body positions.

Reference values for Jamar+ digital dynamometer hand grip strength in healthy adults and in adults with non-communicable diseases or osteoarthritis: the Norwegian Tromsø study 2015-2016

Hand grip strength (HGS) is a key indicator of intrinsic capacity and has shown good predictive ability for morbidity and mortality. Reference values from normative populations are valuable, and such data from the Norwegian population are scarce. Normative values for the digital Jamar+ dynamometer are largely lacking.HGS was assessed in the Norwegian Tromsø study, survey 7 in 2015-2016 for 7824 participants (9324 invited) aged 40+ using a Jamar+ digital dynamometer, and three measurements for each hand were performed following the Southampton protocol. To account for non-response, full Tromsø population data, by age, education and sex, were collected from registry data from microdata.no, a service from Statistics Norway, and were then used as post-stratification weights, to provide standardized HGS values. HGS was higher in men than in women and inversely associated with age. Men and women with a history of non-communicable diseases had lower HGS than those without these conditions, while osteoarthritis was associated with lower HGS only among men. Lower height was associated with lower HGS, especially at younger ages in men. This article provides up-to-date references values for HGS in the community-dwelling population aged 40+ with or without osteoarthritis or non-communicable diseases, in Tromsø, Norway. These reference values will guide clinicians and researchers.

Prediabetes Progression and Regression on Objectively- Measured Physical Function: A Prospective Cohort Study

BACKGRUOUND

Prediabetes leads to declines in physical function in older adults, but the impact of prediabetes progression or regression on physical function is unknown. This study assessed this longitudinal association, with physical function objectivelymeasured by grip strength, walking speed, and standing balance, based on the Health and Retirement Study enrolling United States adults aged >50 years.

METHODS

Participants with prediabetes were followed-up for 4-year to ascertain prediabetes status alteration (maintained, regressed, or progressed), and another 4-year to assess their impacts on physical function. Weak grip strength was defined as <26 kg for men and <16 kg for women, slow walking speed was as <0.8 m/sec, and poor standing balance was as an uncompleted fulltandem standing testing. Logistic and linear regression analyses were performed.

RESULTS

Of the included 1,511 participants with prediabetes, 700 maintained as prediabetes, 306 progressed to diabetes, and 505 regressed to normoglycemia over 4 years. Grip strength and walking speed were declined from baseline during the 4-year followup, regardless of prediabetes status alteration. Compared with prediabetes maintenance, prediabetes progression increased the odds of developing weak grip strength by 89% (95% confidence interval [CI], 0.04 to 2.44) and exhibited larger declines in grip strength by 0.85 kg (95% CI, -1.65 to -0.04). However, prediabetes progression was not related to impairments in walking speed or standing balance. Prediabetes regression also did not affect any measures of physical function.

CONCLUSION

Prediabetes progression accelerates grip strength decline in aging population, while prediabetes regression may not prevent physical function decline due to aging.

Comparison of Grip Strength Measurements by Widely Used Three Dynamometers in Outpatients Aged 60 Years and Over

Grip strength (GS) is widely used in various fields such as sports, rehabilitation, and geriatrics to assess muscle strength, and to diagnose sarcopenia and frailty in older adults. There is a potential for measurement differences among different dynamometers available, and studies comparing GS measurements by variable tools have conflicting results. The two most frequently used dynamometers are the Jamar hydraulic (Jamar) and spring-type hand grip dynamometers, and Jamar has not been compared to Jamar PLUS+ Digital (Jamar+) dynamometer in older adults. So, we aimed to assess GS measurements with the Jamar as the reference standard against Jamar+, and spring-type Takei T.KK. 5401 (Takei) digital dynamometers. One hundred and ten outpatients aged >60 years were included. Inter-instrumental reliability was determined. The differences between dynamometers were evaluated by Bland-Altman plots and measurement error. The measurements with Jamar+, and Takei dynamometers were reliable and valid regarding the Jamar dynamometer. Takei and Jamar+ dynamometers overestimated GS over the Jamar dynamometer. Though the differences in the measured values might be disregarded in clinical practice, individuals defined to have low GS varied by the use of different dynamometers. Grip strength better be measured by the same dynamometer in serial measurements of older individuals.

The Controversial Relationship between Body Mass Index and Handgrip Strength in the Elderly: An Overview

Body mass index (BMI) is one of the most commonly used anthropometric measurements. BMI is measured by dividing an individual's weight by their height. In the elderly, the aging process causes physiological changes to organ systems as well as body composition. The most noticeable changes occur in the musculoskeletal system-that is, of decreased muscle strength. Handgrip strength is one of the most commonly considered criteria to measure muscle strength. Various factors, including age, gender and anthropometric measurements such as BMI, are known to affect a person's muscle strength. In addition, weight and height affect the handgrip strength of an elderly person. However, whether BMI directly affects handgrip strength in the elderly is still debated. Several studies have stated that BMI has a relationship with handgrip strength in the elderly, while other studies have found no relationship between BMI and handgrip strength. BMI and handgrip strength is still controversial and requires further research.

Isokinetic strength assessment of trunk muscle and its relationship with spinal-pelvic parameters in patients with degenerative spinal deformity

BACKGROUND

The incidence rate of degenerative spinal deformity (DSD) has gradually increased in the elderly. Currently, the relationship between the functional status of trunk muscle and the spinal-pelvic parameters of DSD patients remains unclear.

OBJECTIVE

This paper aims to explore the relationship between the two factors and provide new clues for exploring the mechanism of the occurrence and development of DSD.

METHODS

A total of 41 DSD patients treated in our hospital (DSD group) and 35 healthy volunteers (control group) were selected. Muscle strength was evaluated using an IsoMed-2000 isokinetic dynamometer, and the trunk flexor and extensor peak torque (PT) of subjects was measured at a low, medium, and high angular velocity of 30∘/s, 60∘/s, and 120∘/s, respectively. Hand grip strength (HGS) was assessed using an electronic grip dynamometer and Surgimap software was used to measure the spinal-pelvic parameters, including the sagittal vertical axis (SVA), thoracic kyphosis (TK), lumbar lordosis (LL), sacral slope (SS), pelvic tilt (PT), pelvic incidence rate (PI), and PI-LL, and the relationship between trunk muscle function and various parameters was analyzed.

RESULTS

Under the three angular velocities, the flexor and extensor PT values in the DSD group were lower than those in the control group, and only the extensor PT showed a statistically significant difference (P< 0.05). There was no significant difference in HGS between the two groups (P> 0.05). In the DSD group, the extensor PT at 30∘/s was significantly negatively correlated with SVA (P< 0.05). At 60∘/s and 120∘/s, the extensor PT was significantly negatively correlated with SVA and PT (P< 0.05).

CONCLUSION

Trunk extensor strength is significantly lower in DSD patients than in normal controls. The decline in trunk extensor strength in DSD patients is a type of local muscle dysfunction more closely related to the deformity, which is likely involved in the compensatory mechanism of DSD and may reflect the overall imbalance of the trunk.

Association between Handgrip Strength, Skinfold Thickness, and Trunk Strength among University Students

OBJECTIVES

The main goal was to explore the relationship between hand grip strength (HGS), the thickness of the skinfold at multiple sites, and the trunk flexor (TF) and extensor (TE) muscle strength among healthy participants.

METHODS

We employed a cross-sectional design and randomly recruited 40 participants. Ultimately, only 39 participants were included. First, measurements for demographic and anthropometric variables were carried out. After that, the evaluation of hand grip strength and skinfold was performed.

DATA ANALYSIS

Descriptive statistics were used to explore the amount of interaction between the smoking and nonsmoking groups, and a repeated measures analysis of variance was employed. Furthermore, associations between dependent and independent variables were discovered through a multiple linear regression model.

RESULTS

The participants had a mean age of 21.59 ± 1.19 years. The results of the repeated measures analysis of variance validated an acceptable interaction between the trunk and hand grip strength at a significance level of p < 0.01, further emphasized by their moderate association (p < 0.05). Multiple regressions between TE, TF, the independent variables T score, height, and age were also significant (p < 0.05).

CONCLUSIONS

The trunk muscle strength can be used as a health indicator for comprehensive evaluation. The present study also found a moderate relationship between hand grip strength, trunk strength, and T score.

Narrative Review of Sex Differences in Muscle Strength, Endurance, Activation, Size, Fiber Type, and Strength Training Participation Rates, Preferences, Motivations, Injuries, and Neuromuscular Adaptations

ABSTRACT

Nuzzo, JL. Narrative review of sex differences in muscle strength, endurance, activation, size, fiber type, and strength training participation rates, preferences, motivations, injuries, and neuromuscular adaptations. J Strength Cond Res 37(2): 494-536, 2023-Biological sex and its relation with exercise participation and sports performance continue to be discussed. Here, the purpose was to inform such discussions by summarizing the literature on sex differences in numerous strength training-related variables and outcomes-muscle strength and endurance, muscle mass and size, muscle fiber type, muscle twitch forces, and voluntary activation; strength training participation rates, motivations, preferences, and practices; and injuries and changes in muscle size and strength with strength training. Male subjects become notably stronger than female subjects around age 15 years. In adults, sex differences in strength are more pronounced in upper-body than lower-body muscles and in concentric than eccentric contractions. Greater male than female strength is not because of higher voluntary activation but to greater muscle mass and type II fiber areas. Men participate in strength training more frequently than women. Men are motivated more by challenge, competition, social recognition, and a desire to increase muscle size and strength. Men also have greater preference for competitive, high-intensity, and upper-body exercise. Women are motivated more by improved attractiveness, muscle "toning," and body mass management. Women have greater preference for supervised and lower-body exercise. Intrasexual competition, mate selection, and the drive for muscularity are likely fundamental causes of exercise behaviors in men and women. Men and women increase muscle size and strength after weeks of strength training, but women experience greater relative strength improvements depending on age and muscle group. Men exhibit higher strength training injury rates. No sex difference exists in strength loss and muscle soreness after muscle-damaging exercise.

Effect on muscle strength after blood flow restriction resistance exercise in early in-patient rehabilitation of post-chronic obstructive pulmonary disease acute exacerbation, a single blinded, randomized controlled study

BACKGROUND

Early commencement of rehabilitation might counteract the loss of muscle strength due to a chronic obstructive pulmonary disease acute exacerbation (COPDAE). Blood flow restriction resistance exercise (BFR-RE) using a low intensity of training load has demonstrated muscle strength gain in varieties of clinical populations. This trial aimed at studying the efficacy and acceptability of BFR-RE in patients with post-COPDAE which was not reported before.

METHOD

A prospective, assessor blinded, randomized controlled study with 2-week in-patient rehabilitation program with BFR-RE was compared to a matched program with resistance exercise without BFR in patients with post-COPDAE. The primary outcome was the change of muscle strength of knee extensor of dominant leg. The secondary outcomes included changes of hand grip strength (HGS), 6-minute walk test (6MWT) distance, short physical performance battery (SPPB) scores, COPD assessment test (CAT) scores; acceptability and feasibility of BFR-RE; and 1-month unplanned re-admission rate.

RESULTS

Forty-Five post-COPDAE patients (mean age = 76 ± 10, mean FEV1%=49% ± 24%) were analyzed. After training, BFR-RE group and control group demonstrated a statistically significant median muscle strength gain of 20 (Interquartile range (IQR) 3 to 38) Newton(N) and 12 (IQR -9 to 30) N respectively. BFR-RE group showed a significant change in SPPB scores, but not in 6MWT distance and HGS after training. Between groups did not have statistically significant different in all primary and secondary outcomes, though with similar acceptability. Drop-out rate due to training-related discomfort in BFR-RE group was 3.7%.

CONCLUSION

BFR-RE is feasible and acceptable in patients with post-COPDAE. A 2-week inpatient pulmonary rehabilitation with BFR-RE improved muscle strength of knee extensors, but not a greater extent than the same rehabilitation program with resistance exercise without BFR. Further studies could be considered with a longer training duration and progression of resistance load. [ClinicalTrials.gov Identifier: NCT04448236].

Differences in the Relationships Between Muscle Strength, Muscle Mass, Balance Function, and Quality of Life for Middle-Aged and Older Breast Cancer Survivors

PURPOSE

The purpose of this study was to investigate the differences in muscle strength, muscle mass, balance function, and quality of life (QOL) among middle-aged breast cancer survivors (BCSs) and older BCSs.

METHODS

The study included 53 middle-aged (<65 years old) BCSs and 49 older (≥65 years old) BCSs. Muscle strength was evaluated via handgrip and knee extensor strength, and muscle mass was assessed using a body composition test. Balance function was assessed using the Timed Up and Go test and the body sway test. QOL was assessed using the Medical Outcome Study 36-item Short-Form Health Survey.

RESULTS

The older BCSs had significantly lower right grip strength, right knee extension strength, and muscle mass (P < .05) than the middle-aged BCSs. In addition, the body sway test showed that older BCSs had a significant increase in the length of center of pressure compared to middle-aged BCSs (P < .05). Older BCSs showed significantly lower physical functioning subscales in QOL compared to middle-aged BCSs (P < .05). The associations among muscle strength, muscle mass and QOL were more significantly observed in the older BCSs (P < .05). Furthermore, a significant correlation between QOL and balance function was observed in the older BCSs, but not in the middle-aged BCSs (P < .05).

CONCLUSION

There may be associations among muscle strength, muscle mass, balance and QOL in older BCSs, but not in middle-aged BCSs. We believe that the findings of this study will be relevant in the context of planning rehabilitation for older BCSs.

Longitudinal Associations Between Household Solid Fuel Use and Handgrip Strength in Middle-Aged and Older Chinese Individuals: The China Health and Retirement Longitudinal Study

Background

Household solid fuel have been associated with changes of handgrip strength (HGS). However, no study has explored the longitudinal associations between household solid fuel use and HGS. Thus, the aim of our cohort study was to investigate the longitudinal associations between household fuel use and HGS.

Methods

The study was based on the China Health and Retirement Longitudinal Study. A handheld dynamometer was used to measure HGS. Household fuel use statuses were collected using questionnaires. Analyses of covariance were performed to examine the associations between household fuel use and HGS.

Results

The study included 9,382 participants during a 4-year follow-up. The participants who used solid fuel for cooking had more decreases of HGS than those who used clean fuel (P < 0.0001). The least square means (95% CIs) of changes of HGS for participants who used solid fuel and those who used clean fuel for cooking were −1.67 (−2.15, −1.19) and−2.27 (−2.75, −1.79), respectively. The association between fuel use for heating and HGS was non-significant (P = 0.63). The interaction terms of sex to cooking fuel (P = 0.04) and smoking to cooking fuel (P < 0.001) were significant; men and participants who had ever smoked had higher decreases in HGS.

Conclusion

Using household solid fuel for cooking but not heating was associated with more decreases in HGS. Proper ventilation and clean fuel should be promoted for public health.

Effect of the level of manual performance disability caused by exposure to vibration among sailors working on sailing speed vessels

BACKGROUND

hand-arm vibration is one of the typical annoying physical factors. Hand-arm vibration syndrome (HAVS) is a disorder caused by vibrating working tools which vibrate hands beyond the threshold. Long-term HAVS may result in damage to blood vessels, chronic numbness in the fingers, bone injury, and muscular weakness. People are exposed to high-rate noise vibration in a variety of situations, including vessel employment and operating in tiny boats. Moreover, the extant study was conducted to examine manual function disability levels caused by Sailing Speed Vessels (SSV) vibration.

METHODS

The extant study was quasi-experimental research in which, 52 male sailors in SSVs were chosen as the experimental group, and 27 office personnel were selected as the control group. The demographic factors questionnaire, DASH questionnaire, grip and pinch strength tests, the neurosensory exam, and the skill-dexterity test were all employed in this study. SPSS23 software was used to analyze the data.

RESULTS

The findings suggested that the experimental group experienced greater vibration disorder symptoms than the control group. Because the experimental group had a higher score, the individuals experienced poorer circumstances in terms of arm, shoulder, and hand impairment as compared to the control group. The mean grip strength of hands and fingers in two hands of the experimental group was lower than the control group (P < 0.05). There was a statistically significant relationship among grip strengths of both experimental and control groups (P < 0.05). There was a reduction in skill and dexterity of both dominant and non-dominant hands of members in the experimental group. According to the statistical tests, there was no significant association between dominant (P = 0.001) skills and non-dominant (P = 0.010) hands in experimental and control groups. There was not also any significant relationship between skill and dexterity of both hands (P = 0.001) and the dominant hand tweezer test (P = 0.001) in two experimental and control groups. There was a statistically significant association between experimental and control groups in terms of assembly skill and dexterity (P = 0.482).

CONCLUSION

Individuals who are at risk of vibration experience less physical and sensory function. DASH score, grip strength, skill, and dexterity could predict the reduction in physical function disability.

Longitudinal association between muscle strength and depression in middle-aged and older adults: A 7-year prospective cohort study in China

BACKGROUND

Evidence regarding the associations between muscle strength in different parts of the body and depression is lacking. This study examined whether poor muscle strength is associated with a higher incidence of depression in a large cohort of middle-aged and older adults.

METHODS

In total, 5,228 middle-aged and older adults from the China Health and Retirement Longitudinal Study without depression at baseline were followed for 7 years. Their demographic characteristics, chronic diseases and lifestyle behaviors were assessed. After adjusting for relevant variables, a Cox regression was used to determine the relationship between muscle strength and incident depression.

RESULTS

Over 32,544 person-years of follow-up, 1,490 participants developed depression. Low muscle strength at baseline was associated with a higher 7-year incident of depression, even after excluding those who developed depression within 2 years. After adjusting for confounding factors, it was found that a higher baseline relative handgrip strength was a protective factor against depression (HR [95% CI]=0.575 [0.430-0.768] for the lowest quartile vs. the highest quartile; p<0.001). Longer times on the 5TSTS test were a risk factor for depression (HR [95% CI]=1.321 [1.077-1.621] for the lowest quartile vs. the highest quartile; p = 0.007). When the strengths of the upper and lower limbs were considered together, the hazard ratio for depression in people with relatively greater muscle strength was 0.463 (95% CI=0.307-0.699; p<0.001).

CONCLUSIONS

Muscle strength could be predictive of depression, and the combined measurement of upper and lower limb muscle strength can improve the predictive ability.

Effects of Adding Respiratory Training to Osteopathic Manipulative Treatment on Exhaled Nitric Oxide Level and Cardiopulmonary Function in Patients With Pulmonary Arterial Hypertension

Limited research exists regarding nonpharmacologic management of pulmonary arterial hypertension (PAH), except for exercise training. The objective of this study was to investigate the effects of osteopathic manipulative treatment (OMT) alone and combined with respiratory training on fractional exhaled nitric oxide (FeNO), and cardiopulmonary function in patients with PAH. This single-blind, prospective, randomized controlled study included 54 patients with PAH who were randomly allocated to OMT, combined intervention, and control groups. The OMT group (n = 16) and combined intervention group (n = 16) received OMT and yoga respiratory training plus OMT, respectively, twice a week for 8 weeks. The control group (n = 16) received no intervention. All patients undertook an educational lecture. FeNO level, pulmonary function, 6-minute walk distance (6MWD), maximal inspiratory and expiratory pressures, and handgrip strength were assessed at baseline and 8 weeks. Combined intervention and OMT groups significantly improved all outcome measures after 8 weeks of treatment (p <0.01), except mean forced expiratory flow between 25% and 75% of forced vital capacity, which did not change in the OMT group (p >0.05). The control group showed significant deteriorations in 6MWD, inspiratory and peripheral muscle strength, and pulmonary function except peak expiratory flow at 8 weeks (p <0.05). The combined intervention group revealed significantly greater improvements of FeNO, 6MWD, respiratory and peripheral muscle strength, and pulmonary function except mean forced expiratory flow between 25% and 75% of forced vital capacity compared with the OMT group (p <0.05). All outcomes significantly improved in both intervention groups versus the control group (p <0.05). Our study demonstrated that adding respiratory training to OMT provided further benefit to FeNO level and cardiopulmonary function compared with OMT alone and that the OMT might be a useful and safe intervention for patients who cannot attend cardiac rehabilitation programs.

Physical performance in relation to preserved ratio impaired spirometry: a cross-sectional study of community-dwelling older Japanese adults

Preserved ratio impaired spirometry (PRISm) is associated with an increased mortality rate; however, its characteristics have not been clearly identified in Japan. This cross-sectional study of community-dwelling older adults compared physical function between people with PRISm and those with no respiratory issues, from 2014 to 2019. We collected demographic data through interviews and measured respiratory and physical functions. We included 668 older adults (male, 23.5%; mean age, 72.8 ± 5.6 years); the prevalence of PRISm was 12%, while the prevalence of obstruction was 6.9%. Propensity score matching was used to identify control subjects with normal spirometry (n = 80) while minimizing the effects of confounders during comparisons with the PRISm population (n = 80). Compared with community-dwelling older adults with normal lung capacity, older adults with PRISm had a lower forced vital capacity (%FVC; 68.7 ± 9.1% vs. 92.5 ± 12.7%, p < 0.001), lower core muscle endurance (sit-up test: 6.7 ± 5.8 vs. 8.7 ± 6.0, p = 0.032), and a longer one-leg stance duration (52.4 ± 41.1 s vs. 36.4 ± 34.1 s, p = 0.008). In multivariable logistic regression, %FVC and increased one-leg stance were independent predictors of PRISm status. The prevalence of PRISm among community-dwelling elderly Japanese exceeds that of obstructive lung disease and is associated with reduced %FVC and better performance on balance testing.

Hand grip strength and chair stand test amongst Greenlandic Inuit: reference values and international comparisons

Muscle strength is an important predictor for function and mortality among older adults. We measured hand grip strength among 1442 participants aged 15+ years and carried out a 30 second chair stand test among 786 participants aged 55+ years. Neither test has been carried out among the Inuit before. We present reference values for men and women as means with standard deviations and medians with 10^th, 25^th, 75^th and 90^th percentiles. Hand grip strength was higher among men than among women (means 45.2 kg and 25.8 kg; p < 0.0001), in linear regression analyses it increased with height (β_men = 0.69; β_women = 0.46), weight (β_men = 0.24; β_women = 0.08) and body mass index (β_men = 0.56; β_women = 0.24), and decreased with age (β_men = −0.49; β_women = −0.29) and Inuit genetic ancestry (β_men = −0.96; β_women = −0.59). Chair stand score showed similar associations with sex (mean score for men and women 13.8 and 11.5; p < 0.0001), age (β_men = −0.22; β_women = −0.20) and Inuit genetic ancestry (β_men = −0.38; β_women = −0.41). The hand grip strength of the Inuit was at the same level as in European and North American populations whereas chair stand score was lower than that of a mostly white US population.

Assessing Additional Characteristics of Muscle Function With Digital Handgrip Dynamometry and Accelerometry: Framework for a Novel Handgrip Strength Protocol

Maximal handgrip strength (HGS) is a convenient and reliable, but incomplete, assessment of muscle function. Although low HGS is a powerful predictor of poor health, several limitations to maximal HGS exist. The predictive value of HGS is restricted because low HGS is associated with a wide range of unspecified health conditions, and other characteristics of muscle function aside from strength capacity are not evaluated. Current HGS protocol guidelines emphasize the ascertainment of maximal force, which is only a single muscle function characteristic. Muscle function is intrinsically multivariable, and assessing other attributes in addition to strength capacity will improve screenings for age-related disabilities and diseases. Digital handgrip dynamometers and accelerometers provide unique opportunities to examine several aspects of muscle function beyond strength capacity, while also maintaining procedural ease. Specifically, digital handgrip dynamometry and accelerometry can assess the rate of force development, submaximal force steadiness, fatigability, and task-specific tremoring. Moreover, HGS protocols can be easily refined to include an examination of strength asymmetry and bilateral strength. Therefore, evaluating muscle function with new HGS technologies and protocols may provide a more comprehensive assessment of muscle function beyond maximal strength, without sacrificing feasibility. This Special Article introduces a novel framework for assessing multiple attributes of muscle function with digital handgrip dynamometry, accelerometry, and refinements to current HGS protocols. Such framework may aid in the discovery of measures that better predict and explain age-related disability, biological aging, and the effects of comorbid diseases that are amenable to interventions. These additional HGS measures may also contribute to our understanding of concepts such as resilience. Using sophisticated HGS technologies that are currently available and modernizing protocols for developing a new muscle function assessment may help transform clinical practice by enhancing screenings that will better identify the onset and progression of the disabling process.

Low Grip Strength Associated with Clinical Outcomes after Total Hip Arthroplasty - A Prospective Case-Control Study

OBJECTIVE

To assess whether low grip strength (GS) is associated with clinical outcomes after total hip arthroplasty (THA).

METHODS

A prospective case-control study was designed to assess 231 cases of primary THA between January 1, 2015 to May 1, 2018, at an urban tertiary care hospital. Patients were placed into two cohorts based on preoperative GS levels. Low GS in the present study was defined as GS lower than 26 kg for men and 16 kg for women in the dominant hand. Baseline data were prospectively collected and included patient demographics (age, sex, body mass index [BMI]), the surgeon's diagnoses, medical history, length of stay, and American Society of Anaesthesiologists' (ASA) score. Clinical outcomes included surgery- and prosthesis-related variables. The Harris hip score (HHS) and the Short Form Health Survey (SF-12) were completed at the baseline visit and at 1 and 2 years postoperatively in the outpatient department to assess the hip's function and quality of life. Differences in baseline data, length of study (LOS), 90-day postoperative complications, and hospital readmissions were compared. Besides, the correlations between GS and Harris hip score (HHS) and Short Form score (SF-12) were tested.

RESULTS

A total of 202 participants have completed records for analysis finally. The patients were followed up for an average of 24.8 months postoperatively (24-26 months). Eighty-two patients (40.6%) had low GS before THA. Patients with low GS were more likely to be female, older, fracture of femoral head or neck as the primary cause, albumin <3.5 g/dL, and have a lower BMI, higher ASA score, increased rates of the pressure sore, blood transfusion, and LOS compared to normal GS (all P < 0.05). Also, patients in the low GS cohort showed a statistically significant increased unplanned hospital readmissions and decreased discharge home compared to normal GS (both P < 0.05). There was an increasing rate of complications between the two cohorts, for cardiac complications, pressure sore after THA, respiratory complications, urinary tract infection, stroke, and DVT (all P < 0.05). A partial correlation test by controlling medical comorbidities and demographic factors was used to determine the correlation between GS and HHS. There was a significant correlation between them (r = -0.673; P = 0.002). A similar condition was detected in the correlation between GS and SF-12 (r = 0.645; P = 0.001).

CONCLUSIONS

Clinicians should be encouraged to include GS assessment in their evaluation of patients who planned to undergo THA in order to optimize the treatment of high-risk individuals.

Normative reference values of handgrip strength for Brazilian older people aged 65 to 90 years: Evidence from the multicenter Fibra‑BR study

BACKGROUND

Handgrip strength (HGS) is an indicator of muscle strength, suited for evaluating the aging process. Its use depends on the availability of reliable normative reference values (NRV). The main objective of this study is to provide NRV of HGS for Brazilians aged 65 to 90 years.

METHODS

Participants were from the Frailty in Brazilian Older People research. 2,999 successful aging (SA) subjects comprised the development sample. HGS was measured using a hydraulic dynamometer. Obtaining NRV involved regressing HGS on age per sex-height strata, fitting separate fractional polynomial (FP) models for the mean and coefficient of variation. Model fit was assessed via standardized residuals, probability/quantile plots, and comparing observed to normal expected percentages of subjects falling within specified centile intervals. For validation, the latter procedure was applied to 2,369 unsuccessfully aging (UA) subjects.

RESULTS

Across strata, the best-fitting models for the means were FP of power 1. FP models for the CV indicated age invariance, entailing steady heteroscedastic age decline in SD since coefficients for the means were negative and SD = CV×mean. All models adjusted well. Centiles distributions for the SA and UA populations showed anticipated patterns, respectively falling on and below the normative expected centile references. Results (NRV) are presented in tables and centile charts. Equations are also provided.

CONCLUSION

NRV/charts may be endorsed for routine use, while still tested further. They would aid professionals caring for older people, not only to identify those at risk and eligible for immediate provisions, but also in planning prevention and rehabilitation measures.

Can We Use Grip Strength to Predict Other Types of Hand Exertions? An Example of Manufacturing Industry Workers

Background: There are different types of hand motions in people’s daily lives and working environments. However, testing duration increases as the types of hand motions increase to build a normative database. Long testing duration decreases the motivation of study participants. The purpose of this study is to propose models to predict pinch and press strength using grip strength. Methods: One hundred ninety-eight healthy volunteers were recruited from the manufacturing industries in Central Taiwan. The five types of hand motions were grip, lateral pinch, palmar pinch, thumb press, and ball of thumb press. Stepwise multiple linear regression was used to explore the relationship between force type, gender, height, weight, age, and muscle strength. Results: The prediction models developed according to the variable of the strength of the opposite hand are good for explaining variance (76.9–93.1%). Gender is the key demographic variable in the predicting models. Grip strength is not a good predictor of palmar pinch (adjusted-R²: 0.572–0.609), nor of thumb press and ball of thumb (adjusted-R²: 0.279–0.443). Conclusions: We recommend measuring the palmar pinch and ball of thumb strength and using them to predict the other two hand motions for convenience and time saving.

Normative Hand Strength of Healthcare Industry Workers in Central Taiwan

Objectives: The purpose of this study is to establish the norms of hand grip strength in the healthcare industry in Taiwan and propose models to predict the strength of hand movement by regression with demographic and anthropometric factors. Methods: This is a cross-sectional study with a stratified convenience sample of workers in healthcare service industries in central Taiwan. Three hundred twenty-nine healthy subjects were recruited. Strength of different hand movement were tested three times in both hands and rests were given between tests. Results: Female strength of these hand movement was 59.1% to 73.0% that in males (p < 0.001). In general, the hand strength of male workers in the healthcare industry was less than that of male workers in the manufacturing industry (p < 0.001). In the prediction model, sex and weight played important roles in predicting hand strength. Conclusions: The norms of different types of hand strength was investigated the first time in workers in the healthcare industry in Taiwan. The tasks performed by healthcare personnel vary widely, and this variable should be considered in a future prediction model.

Assessment of isokinetic trunk muscle strength and its association with health-related quality of life in patients with degenerative spinal deformity

Background

A considerable portion of the elderly population are increasingly afflicted by degenerative spinal deformity (DSD), which seriously affects patient health-related quality of life (HRQoL). HRQoL index is used across many studies to show correlations between radio-graphical alignment, disability, and pain in patients with DSD. However, imaged structural deformity represents only one aspect for consideration, namely, the disability effect of DSD. We assessed the isokinetic strength of trunk muscle in patients with degenerative spinal deformity (DSD), and investigated its relationship with HRQoL.

Methods

In total, 38 patients with DSD (DSD group) and 32 healthy individuals (control group) were recruited. Both groups were homogeneous for age, weight, height and body mass index (BMI). Assessments were performed using the isokinetic dynamometer IsoMed-2000; trunk extensor, flexor strength and flexion/extension (F/E) ratios were explored concentrically at speeds of 30°, 60° and 120° per second. The grip strength of both hands was measured using a hand-held dynamometer. Visual analogue scale (VAS) scores, the Oswestry Disability Index (ODI), a Roland-Morris disability questionnaire (RDQ), and a 36-item Short Form Health Survey (SF-36) evaluated patient HRQoL. Correlations between trunk strength and HRQoL were analyzed.

Results

When compared with the control group, the DSD group showed lower trunk extensor strength at three velocity movements, and higher F/E ratios at 60° and 120°/s (p < 0.05). Both groups exhibited similar trunk flexor strength and grip strength (p > 0.05). In DSD group, trunk extensor strength at 60°/s was negatively associated with ODI and RDQ (p < 0.05). A negative relationship between trunk flexor strength at 120°/s and ODI was also recorded (p < 0.05). In addition, trunk extensor strength at 60°/s and trunk flexor strength at 120°/s were positively correlated with physical functioning and role-physical scores according to the SF-36 (p < 0.05).

Conclusions

We identified isolated trunk extensor myopathy in DSD, which causes an imbalance in trunk muscle strength. Isokinetic trunk extensor strength at 60°/s and trunk flexor strength at 120°/s can predict disability, and decrease physical HRQoL in DSD patients.

The Association between Health Literacy and Gait Speed in Community-Dwelling Older Adults

The association between gait speed, a vital health outcome in older adults, and health literacy, an important health promotion aspect, is unclear. This study examined the relationship of gait speed with health literacy, physical function, and cognitive function in community-dwelling older adults. The subjects were 240 older adults (52 men, mean age 73.8 ± 6.0 years). Gender, age, and education were self-reported, while height and weight were measured directly. Health literacy was evaluated using Communicative and Critical Health Literacy (CCHL). Grip strength, knee extension strength, toe-grip strength, sit-up test, sit-and-reach test, one-leg stance test time, 30-s chair-stand test (CS-30), and normal gait speed were measured. Subjects were divided into two groups based on normal gait speed—fast (speed ≥ 1.3 m/s) and slow (<1.3 m/s). In the logistic regression analysis, the dependent variable was normal gait speed (fast/slow). Four logistic regression models were utilized to determine whether health literacy affects gait speed. Height and CCHL were found to independently affect gait speed. That health literacy influences gait speed is a new discovery.

The effect of a pre- and post-operative exercise programme versus standard care on physical fitness of patients with oesophageal and gastric cancer undergoing neoadjuvant treatment prior to surgery (The PERIOP-OG Trial): Study protocol for a randomised controlled trial

BACKGROUND

Advances in peri-operative oncological treatment, surgery and peri-operative care have improved survival for patients with oesophagogastric cancers. Neoadjuvant cancer treatment (NCT) reduces physical fitness, which may reduce both compliance and tolerance of NCT as well as compromising post-operative outcomes. This is particularly detrimental in a patient group where malnutrition is common and surgery is demanding. The aim of this trial is to assess the effect on physical fitness and clinical outcomes of a comprehensive exercise training programme in patients undergoing NCT and surgical resection for oesophagogastric malignancies.

METHODS

The PERIOP-OG trial is a pragmatic, multi-centre, randomised controlled trial comparing a peri-operative exercise programme with standard care in patients with oesophagogastric cancers treated with NCT and surgery. The intervention group undergo a formal exercise training programme and the usual care group receive standard clinical care (no formal exercise advice). The training programme is initiated at cancer diagnosis, continued during NCT, between NCT and surgery, and resumes after surgery. All participants undergo assessments at baseline, post-NCT, pre-surgery and at 4 and 10 weeks after surgery. The primary endpoint is cardiorespiratory fitness measured by demonstration of a 15% difference in the 6-min walk test assessed at the pre-surgery timepoint. Secondary endpoints include measures of physical health (upper and lower body strength tests), body mass index, frailty, activity behaviour, psychological and health-related quality of life outcomes. Exploratory endpoints include a health economics analysis, assessment of clinical health by post-operative morbidity scores, hospital length of stay, nutritional status, immune and inflammatory markers, and response to NCT. Rates of NCT toxicity, tolerance and compliance will also be assessed.

DISCUSSION

The PERIOP-OG trial will determine whether, when compared to usual care, exercise training initiated at diagnosis and continued during NCT, between NCT and surgery and then during recovery, can maintain or improve cardiorespiratory fitness and other physical, psychological and clinical health outcomes. This trial will inform both the prescription of exercise regimes as well as the design of a larger prehabilitation and rehabilitation trial to investigate whether exercise in combination with nutritional and psychological interventions elicit greater benefits.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03807518 . Registered on 1 January 2019.

Factors Affecting Reliability of Grip Strength Measurements in Middle Aged and Older Adults

Background: Grip strength is a well-established marker of frailty and a good predictor of mortality that has been measured in a diverse range of samples including many population studies. The reliability of grip strength measurement in longitudinal studies is not well understood. Methods: Participants (n=130) completed a baseline and repeat health assessment in the Irish Longitudinal Study on Ageing. Grip strength was assessed using dominant and non-dominant hands (two trials on each). Repeat assessments were conducted 1-4 months later and participants were randomised into groups so that 50% changed time (morning or afternoon assessment) and 50% changed assessor between assessments. Intra-class correlation (ICC) and minimum detectable change (MDC95) were calculated and the effects of repeat assessment, time of day and assessor were determined. Results: Aggregated measures had little variation by repeat assessment or time of day; however, there was a significant effect of assessor (up to 2 kg depending on the measure used). Reliability between assessments was good (ICC>0.9) while MDC95 ranged from 5.59–7.96 kg. Non-aggregated measures alone, taken on the non-dominant hand were susceptible to repeat assessment, time of day, assessor and repeated measures within-assessment effects whereas the dominant hand was only affected by assessor.   Conclusions: Mean and maximum grip strength had a higher ICC and lower MDC95 than measures on the dominant or non-dominant hands alone. The MDC95 is less than 8 kg regardless of the specific measure reported. However, changing assessor further increases variability, highlighting the need for comprehensive assessor training and avoiding changes within studies where possible.

Management challenges for chronic dysimmune neuropathies during the COVID-19 pandemic

Since March 2020, the COVID-19 pandemic has led to the need to re-think the delivery of services to patients with chronic dysimmune neuropathies. Telephone/video consultations have become widespread but have compounded concerns about objective evaluation. Therapeutic decisions need, more than ever before, to be considered in the best interests of both patients, and society, while not denying function-preserving/restoring treatment. Immunoglobulin therapy and plasma exchange, for those treated outside of the home, expose patients to the hazards of hospital or outpatient infusion centers. Steroid therapy initiation and continuation pose increased infectious risk. Immunosuppressant therapy similarly becomes highly problematic, with the risks of treatment continuation enhanced by uncertainties regarding duration of the pandemic. The required processes necessitate considerable time and effort especially as resources and staff are re-deployed to face the pandemic, but are essential for protecting this group of patients and as an integral part of wider public health actions.

The Study of Health-Related Fitness Normative Scores for Nepalese Older Adults

Physical fitness tests are important to maintain and promote the health status of people. The purpose of this study was to develop health-related fitness evaluation norms according to the age and gender of Nepalese older adults. One thousand nine subjects (449 males, 560 females) above 60 years, residing in 19 wards (rural and urban) of Dhangadhi Sub-Metropolitan City participated in this study. The test included the PAR-Q (Physical Activity Readiness Questionnaire), social aspects questionnaire, blood pressure test, height, weight, BMI (body mass index), percent body fat, and four physical fitness components (grip strength, 1-minute sit-to-stand, sit and reach, and 2-minute step tests). Mean, SD, and fitness evaluation norms for each component were obtained after the main test and statistical analyses. This study showed higher BMI and percent body fat in female age groups than in male age groups. Grip strength, relative grip strength, sit-to-stand, and 2-minute steps scores were better in male age groups than in female age groups, but in contrast, flexibility was better in female age groups. This study may help the related sectors to assess physical fitness, identify fitness levels, and develop appropriate physical activities or exercise programs for older adults based on age.

A Pilot Study of Five Types of Maximum Hand Strength among Manufacturing Industry Workers in Taiwan

Background: The purpose of this study is to collect five types of maximum hand strength among workers in the manufacturing industry in Taiwan. Methods: This study is a cross sectional study with a stratified and convenient sample of workers on the production line in manufacturing industries in Central Taiwan. In total, we recruited 198 healthy subjects to participate in this study. Five types of hand strength were measured in both hands three times with 3 min rests between trials. Results: The strength of females for these five types of hand exertions were 52.0% to 67.6% of the strength of males (p < 0.001). For both genders, there was a main effect for the types of hand strength for the right hand (p < 0.001) and the left hand (p < 0.001). In general, the hand strength in U.S. and EU countries was 1.2 to 1.7 times greater than the strength among the three types of hand exertions in this study. Conclusion: These results can be used to evaluate the musculoskeletal burdens on the upper extremities in the manufacturing industry and could also be used for tool and job design and job modifications.

CORP: Measurement of upper and lower limb muscle strength and voluntary activation

Muscle strength, the maximal force-generating capacity of a muscle or group of muscles, is regularly assessed in physiological experiments and clinical trials. An understanding of the expected variation in strength and the factors that contribute to this variation is important when designing experiments, describing methodologies, interpreting results, and attempting to replicate methods of others and reproduce their findings. In this review (Cores of Reproducibility in Physiology), we report on the intra- and inter-rater reliability of tests of upper and lower limb muscle strength and voluntary activation in humans. Isometric, isokinetic, and isoinertial strength exhibit good intra-rater reliability in most samples (correlation coefficients ≥0.90). However, some tests of isoinertial strength exhibit systematic bias that is not resolved by familiarization. With the exception of grip strength, few attempts have been made to examine inter-rater reliability of tests of muscle strength. The acute factors most likely to affect muscle strength and serve as a source of its variation from trial-to-trial or day-to-day include attentional focus, breathing technique, remote muscle contractions, rest periods, temperature (core, muscle), time of day, visual feedback, body and limb posture, body stabilization, acute caffeine consumption, dehydration, pain, fatigue from preceding exercise, and static stretching >60 s. Voluntary activation, the nervous system’s ability to drive a muscle to create its maximal force, exhibits good intra-rater reliability when examined with twitch interpolation (correlation coefficients >0.80). However, inter-rater reliability has not been formally examined. The methodological factors most likely to influence voluntary activation are myograph compliance and sensitivity; stimulation location, intensity, and inadvertent stimulation of antagonists; joint angle (muscle length); and the resting twitch.

Carpal tunnel release with versus without flexor retinaculum reconstruction for carpal tunnel syndrome at short- and long-term follow up-A meta-analysis of randomized controlled trials

Background

Carpal tunnel syndrome is a common neuropathy disorder for which surgical treatment consists of release and reconstruction of the flexor retinaculum. Reports of postoperative clinical outcomes after carpal tunnel release with or without flexor retinaculum reconstruction in several studies are controversial. This meta-analysis aimed to compare the efficacy and safety of carpal tunnel release with or without flexor retinaculum reconstruction.

Methods

The PubMed, EMBASE, Web of Science, Ovid, Cochrane Library and Clinical Tri Org databases were searched for randomized controlled trials that compared carpal release with and without transverse carpal ligament reconstruction for carpal tunnel syndrome. Outcomes included postoperative Boston Carpal Tunnel Questionnaire Symptom Severity Scale (SSS), Functional Status Scale (FSS), grip strength and complications. The follow-up time was categorized into short-term (0-3mon) and long-term(>3mon).

Results

A total of 7 studies with 613 patients met the inclusion criteria and were analyzed in detail. Statistical analysis showed no significant difference between two groups on postoperative long-term grip strength (MD 5.85, 95% CI -1.05 to 12.76) long-term SSS (MD -0.31, 95% CI -0.75 to 0.13) and occurrence of complications (RR 1.14, 95% CI 0.84 to 1.54), whereas statistically significant difference was found between groups regarding short-term grip strength (MD 1.51, 95% CI 0.86 to 2.17) and long-term FSS (MD -0.34, 95% CI -0.47 to -0.21).

Conclusion

Carpal tunnel release with flexor retinaculum reconstruction for carpal tunnel syndrome may result in improved long-term functional status while there’s no advantage regarding grip strength, symptom severity and safety over individual carpal tunnel release in short- and long-term outcomes.

Differences in Balance Function Between Cancer Survivors and Healthy Subjects: A Pilot Study

Older adults who have survived cancer experience significantly more falls compared with healthy adults. Adult cancer survivors may also have a lower balance function than healthy adults. We examined muscle strength and balance function among 19 cancer survivors and 14 healthy subjects. The mean age of the cancer survivors was 51.5 ± 11.2 years; 6 men and 13 women. Cancer diagnoses included breast cancer, retroperitoneal sarcoma, acute leukemia, lung cancer, colorectal cancer, thyroid cancer, Ewing’s sarcoma, and tongue cancer. The mean age of healthy subjects was 47.4 ± 14 years; 3 men, 11 women. Muscle strength was assessed using hand grip and knee extensor strength tests. Balance function was evaluated using the Timed Up and Go (TUG) test, and body sway was tested using a force platform. No significant differences were found with respect to right and left grip strength or right and left knee extension strength between the 2 groups. A significantly higher TUG time was observed in cancer survivors than in healthy subjects (P < .05). With eyes open, the area of the center of pressure was significantly larger in cancer survivors than in healthy subjects (P < .05). Similarly, the length per area was significantly lower both with eyes open and closed for cancer survivors than for healthy subjects (P < .05). TUG was significantly correlated with muscle strength in both groups (P < .05). However, no body sway parameters were related to muscle strength in either group. Cancer survivors had lower balance function that might not have been related to muscle strength. Cancer survivors should be evaluated for balance function as there is a potential for impairment. The findings of this study will be relevant for planning the prevention of falls for cancer survivors.

Cancer survivors exhibit a different relationship between muscle strength and health-related quality of life/fatigue compared to healthy subjects

We investigated the difference in relationship between muscle strength and quality of life (QOL)/fatigue in long-term cancer survivors and healthy subjects. Thirty-six cancer survivors and 29 healthy subjects were assessed for body composition and bone status at the calcaneus using the Osteo Sono Assessment Index. Muscle strength was evaluated via handgrip and knee extensor strength. Health-related QOL was assessed using the Medical Outcome Study 36-item Short-Form Health Survey. Fatigue was measured using the brief fatigue inventory. Cancer survivors exhibited lower QOL scores in the physical functioning, physical role function, bodily pain and general health domains (p < .05). Grip and knee extension muscle strength in cancer survivors was positively correlated with the physical function and bodily pain of QOL (p < .05). The usual fatigue subscale score was only significantly higher in cancer survivors than in healthy subjects (p < .05). However, there were no correlations between muscle strength and fatigue in cancer survivors. Our results showed that muscle strength was an important factor for improving QOL in cancer survivors. We believe that the findings of this study will be relevant in the context of planning rehabilitation for cancer survivors.

Hand grip strength in patients with chronic obstructive pulmonary disease

PURPOSE

Hand grip strength (HGS) is a simple way of predicting the risk of cardiovascular disease and all-cause mortality in the general population. However, the practical significance of grip strength in patients with COPD is uncertain. The aim of this study was to compare HGS between subjects with and without COPD and to evaluate its clinical relevance in patients with COPD by using a national survey.

METHODS

Data were collected from the Korean National Health and Nutrition Examination Survey. The study included 421 adults with COPD and 2,542 controls who completed questionnaires, spirometry, and a HGS test. HGS was compared between subjects with and without COPD, and the association between grip strength, lung function, and quality of life (QoL) was evaluated.

RESULTS

The mean HGS was 33.3±9.1 kg in the COPD group and 29.9±9.5 kg in the non-COPD group; adjusted HGS was 30.9±0.33 kg and 30.9±0.11 kg, respectively (P=0.99). HGS was not related to forced vital capacity (β=0.04, P=0.70) or forced expiratory volume in 1 second (β=0.11, P=0.24) in multivariable analysis. HGS was independently associated with the EQ-5D index, but the relationship was stronger in the COPD group (β=0.30, P<0.001) than in the non-COPD group (β=0.21, P<0.001). The results were similar for each component of the EQ-5D, including mobility (β=-0.25, P<0.001), daily activity (β=-0.19, P=0.01), pain/discomfort (β=-0.32, P<0.001), and anxiety/depression (β=-0.16, P=0.01).

CONCLUSION

HGS was not different between subjects with and without COPD, but was associated with QoL - including mobility, daily activity, pain/discomfort, and anxiety/depression - in patients with COPD. The HGS test could be used as a marker of QoL in patients with COPD and could assist risk stratification in clinical practice.