Reference Respiratory Muscle Strength Values and a Prediction Equation Using Physical Functions for Pulmonary Rehabilitation in Korea

BACKGROUND

In Korea, tests for evaluating respiratory muscle strength are based on other countries' clinical experience or standards, which can lead to subjective evaluations. When evaluating respiratory function based on the standards of other countries, several variables, such as the race and cultures of different countries, make it difficult to apply these standards. The purpose of this study was to propose objective respiratory muscle strength standards and predicted values for healthy Korean adults based on age, height, weight, and muscle strength, by measuring maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and peak cough flow (PCF).

METHODS

This cross-sectional study analyzed MIP, MEP, and PCF in 360 people, each group comprising 30 adult men and women aged 20-70, diagnosed as healthy after undergoing medical check-ups at a general hospital. Hand grip strength (HGS) and the five times sit-to-stand test (FTSST) results were also recorded. Correlations among respiratory muscle strength, participant demographics, and overall muscle strength were evaluated using Pearson's correlation analysis. The predicted values of respiratory muscle strength were calculated using multiple regression analysis.

RESULTS

Respiratory muscle strength differed from the values reported in studies from other countries. In the entire samples, both MIP and MEP had the highest correlations with peak HGS (r = 0.643, r = 0.693; P < 0.05), while PCF had the highest correlation with forced expiratory volume in 1 s (r = 0.753; P < 0.05). Age, body mass index, peak HGS, and FTSST results were independent variables affecting respiratory muscle strength. A predictive equation for respiratory muscle strength was developed using the multiple regression equation developed in this study.

CONCLUSION

Respiratory muscle strength index may differ by country. For more accurate diagnoses, standard values for each country are required. This study presents reference values for Korea, and a formula for estimation is proposed when no respiratory muscle strength measurement equipment is available.

TRIAL REGISTRATION

Clinical Research Information Service Identifier: KCT0006778.

EFFECT OF WRIST WRAP IN HANDGRIP STRENGTH IN CROSSFIT

Objectives

Analyze wrist wrap influence on the values of maximum handgrip strength and dynamic resistance.

Methods

A controlled randomized cross-over trial including 54 Crossfit participants randomly assigned to two groups. Group 1 began the series of tests with control wrapping, and Group 2 started with functional wrapping. Alternate series of four dynamic grip strength resistance tests were performed, and the resistance and fatigue values were calculated.

Results

The values obtained from the grip tests did not indicate any effect from the wrist wrap for an increase in maximum grip strength (35.7 vs. 35.6 kg; p=0.737) or greater endurance (78.2 vs. 77.8%; p=0.549). Fatigue was also equal in both groups (mean differences between the groups: 0.1 kg, CI= -0.7-0.8; p=0.779).

Conclusion

The hypothesis that using a wrist wrap increases maximum strength and dynamic handgrip endurance was rejected in this study. Evidence Level I; Randomized control trial .

Inhibitory Effects of Prolonged Focal Muscle Vibration on Maximal Grip Strength and Muscle Activity of Wrist and Extrinsic Finger Flexor Muscles

Objective

The objective of this study was to identify effective stimulus time by quantifying the inhibitory effects of focal muscle vibration (FMV) on maximal grip strength and muscle activities of the wrist and extrinsic finger flexors.

Methods

A randomized repeated-measures design was used in this study. A total of 22 healthy volunteers (mean age, 20.9 years) participated. An FMV of 86 Hz was applied to the anterior surface of the distal forearm under the following 3 conditions: no FMV (control), 5-minute FMV, and 10-minute FMV. Maximal grip strength was measured before and after FMV. The muscle activities of the flexor digitorum superficialis, flexor digitorum profundus (FDP), and flexor carpi ulnaris were simultaneously recorded using surface electromyography. Discomfort and complications following FMV were also assessed.

Results

Compared with the control group, a significant decrease in muscle activity was observed in both the flexor digitorum superficialis and flexor carpi ulnaris after 5 and 10 minutes of FMV. In contrast, there was no significant decrease in the maximal grip strength or FDP muscle activity after either FMV condition. The discomfort was significantly higher immediately after both FMV conditions than in the control group, but it decreased 15 minutes after FMV, indicating no significant difference among the 3 conditions. Redness and/or swelling were observed in 13.6% and 36.3% of the participants after 5 and 10 minutes of FMV, respectively.

Conclusion

Five-minute FMV to the distal forearm could be a useful therapeutic method with few complications. However, the FMV in this area alone was not sufficient to suppress the muscle activity of the FDP located in the deep layer.

Children With Cerebral Palsy Show Higher Static-But Not Higher Dynamic-Motor Fatigability in Grip and Pinch Tasks Than Children With Typical Development Do

OBJECTIVE

The purpose of this study was to investigate differences in static and dynamic motor fatigability during grip and pinch tasks between children with unilateral spastic cerebral palsy (USCP) and children with typical development (TD) and between preferred and nonpreferred hands.

METHODS

Fifty-three children with USCP and 53 age-matched children with TD (mean = 11 years 1 month; SD = 3 years 8 months) participated in 30-second maximum exertion sustained and repeated grip and pinch tasks. For sustained tasks, the Static Fatigue Index and the ratio of mean force between the first and last thirds of the curve were calculated. For repeated tasks, the ratio of mean force and the ratio of numbers of peaks between the first and last thirds of the curve were calculated.

RESULTS

Higher Static Fatigue Index scores for grip and pinch were found with USCP in both hands and between hands in both groups. Dynamic motor fatigability showed inconsistent results, with higher levels of fatigability in children with TD than in children with USCP for grip in the ratio of mean force between the first and last thirds of the curve in nonpreferred hands and in the ratio of number of peaks between the first and last thirds of the curve in preferred hands.

CONCLUSION

Higher motor fatigability in children with USCP than in children with TD was found for static but not dynamic grip and pinch. Underlying mechanisms may play different roles in static and dynamic motor fatigability.

IMPACT

These results highlight that static motor fatigability in grip and pinch tasks should be part of a comprehensive upper limb assessment and that this could be the target of individualized interventions.

Test-Retest Reliability of a Static and Dynamic Motor Fatigability Protocol Using Grip and Pinch Strength in Children With Cerebral Palsy

OBJECTIVE

The purpose of this study was to investigate the test-retest reliability, measurement error, and interpretability of new motor fatigability outcomes of grip and pinch strength for children with unilateral cerebral palsy (UCP).

METHODS

Motor fatigability during grip and pinch strength was measured twice (within 48 hours) in both hands of 50 children (mean age = 11 years 2 months; 14, 31, and 5 children with Manual Ability Classification System levels I, II, and III, respectively) using a 30-second static and dynamic maximum exertion protocol. For static motor fatigability, the Static Fatigue Index (SFI) and mean force (Fmean) in the first (Fmean1) and last (Fmean3) 10 seconds were calculated. For dynamic motor fatigability, Fmean1, Fmean3, and the number of peaks in the first and last 10 seconds were calculated.

RESULTS

For static motor fatigability, the intraclass correlation coefficients (ICCs) were moderate to high for Fmean1 and Fmean3 (0.56-0.88), and the SFI showed low to moderate reliability (ICC = 0.32-0.72). For dynamic motor fatigability, the ICCs were moderate to high for all outcomes (0.54-0.91). The standard error of measurement agreement and the smallest detectable difference agreement were large in all outcomes, except for the SFI in static motor fatigability. Details per age group are provided. In general, younger children (6-11 years old) showed lower reliability than older children (12-18 years old).

CONCLUSION

Most outcome measures for static and dynamic motor fatigability of grip and pinch strength show moderate to high reliability in children with UCP, indicating that these tests can be used reliably to investigate the presence of motor fatigability in UCP, especially in older children. Standard error of measurement agreement and smallest detectable difference agreement indicated that these outcome measures should be interpreted with caution when evaluating change.

IMPACT

Most of the proposed outcome measures for static and dynamic motor fatigability of grip and pinch are reliable in children with UCP and can be used for discriminative purposes.

An Investigation of Maximal Strength of the Upper Limb Bilaterally in Individuals With Lateral Elbow Tendinopathy: A Systematic Review With Meta-Analysis

OBJECTIVE

The aim of this study was to investigate whether there is evidence of bilateral upper limb strength deficits in individuals with unilateral lateral elbow tendinopathy (LET).

METHODS

The electronic databases Medline via Ovid, PubMed, and Scopus were searched from inception to March 2020. Included studies encompassed maximal strength outcomes of any upper limb and appendicular musculature in individuals with LET and an asymptomatic comparator. Study quality was rated using a modified version of the Epidemiological Appraisal Instrument. Hedges g effect sizes (ES) and 95% CIs were calculated for comparisons of maximal strength in the LET group and an asymptomatic control group. Meta-analysis using a random-effects model was performed when possible.

RESULTS

Fourteen studies were included. Quality appraisal resulted in a mean Epidemiological Appraisal Instrument score of 46% (SD = 10%). Meta-analysis revealed strength deficits in shoulder abduction (pooled ES = -0.37 [95% CI = -0.62 to -0.12]) and shoulder external rotation (pooled ES = -0.55 [95% CI = -0.83 to -0.28]) of the symptomatic limb compared with an asymptomatic control group. Meta-analysis also revealed maximal strength deficits in the upper trapezius (pooled ES = -0.26 [95% CI = -0.49 to -0.02]) of the asymptomatic limb compared with an asymptomatic control group. There was also consistent evidence for strength deficits in the serratus anterior, lower trapezius, and wrist extensor muscles and deficits in grip strength of the symptomatic limb as well as strength deficits in the wrist extensor muscles of the asymptomatic limb in individuals with unilateral LET.

CONCLUSION

In individuals with LET, there were maximal strength deficits in shoulder abduction, shoulder external rotation, serratus anterior and lower trapezius muscles, and wrist extension, as well as deficits in grip strength of the symptomatic limb compared with an asymptomatic control group. In addition, there appeared to be strength deficits in the upper trapezius muscle, wrist extension, and metacarpophalangeal joint flexion and extension, as well as deficits in grip strength of the asymptomatic limb in individuals with LET compared with an asymptomatic control group. These results suggest bilateral strength deficits.

IMPACT

These findings highlight the importance of a thorough physical examination and appropriate strengthening intervention for the upper limb with a focus on shoulder and scapular stabilizers, in addition to forearm muscles, in individuals with LET.

LAY SUMMARY

In people with tennis elbow, widespread strength deficits, including weakness of the shoulder, forearm, and wrist muscles, may exist. Interestingly, some of these weaknesses appear on both the affected and the unaffected sides in people with tennis elbow. A physical therapist can help strengthen these areas.

Poor handgrip strength determined clinically is associated with falls in older women

Objectives:

To assess the association between poor handgrip strength (HGS) determined by clinical criterion and incidence of falls in older women.

Methods:

The cohort included 195 women (68.1±6.2 years) who were assessed for HGS (Jamar Dynamometer) at baseline and were prospectively followed for 18 months. FNIH Sarcopenia threshold of HGS adjusted for body mass index (<0.56) was used for clinical determination of poor HGS. Association between poor HGS and incidence of falls was analyzed using Cox hazard models in the total cohort and in a stratified analysis by balance status.

Results:

During the follow-up, 53 (27%) women experienced at least one fall. In a multivariable model, poor HGS was associated with approximately 3-fold increased risk for falls [Hazard Ratio (HR)=2.73, 95% Confidence Interval (CI)=1.28–5.82, p=0.009]. In a stratified analysis, women with impaired balance exhibited even greater risk for falls (HR=3.85, 95%CI=1.47–10.12, p=0.011), although no association was found in women with normal balance (p=0.459).

Conclusions:

Poor HGS based on clinical criterion is independently associated with higher risk of falls in older women, particularly in those with impaired balance. These results suggest potential prognostic value of FNIH Sarcopenia threshold for risk stratification and referring high-risk individuals to fall prevention programs.

Cancer Survivors with Low Hand Grip Strength Have Decreased Quality of Life Compared with Healthy Controls: The Korea National Health and Nutrition Examination Survey 2014-2017

BACKGROUND

Cancer survivors experience decreased physical function and reduced muscle strength, which leads to lower quality of life (QOL). The hand grip strength (HGS) can be a predictor of poor health-related QOL as a parameter of sarcopenia. The purpose of this study was to investigate the relationship between low HGS and QOL in cancer survivors and healthy controls.

METHODS

We analyzed 392 cancer survivors and 1,176 healthy controls from the Korea National Health and Nutrition Examination Survey, 2014-2017. We defined low HGS as 2 standard deviation values for healthy young Korean adults from a previous study. QOL was evaluated using the European Quality of Life Scale-Five Dimensions. A complex sample logistic regression model was used to assess the relationship between each dimension of low HGS and QOL.

RESULTS

The odds ratios (ORs) for decreased QOL were significantly higher in male cancer survivors with low HGS on self-care (OR, 8.51; 95% confidence interval [CI], 1.69-42.83) and usual activities (OR, 6.63; 95% CI, 1.22-36.03). The ORs for problems in mobility (OR, 5.87; 95% CI, 2.04-16.91), usual activities (OR, 14.46; 95% CI, 3.84-54.44), pain/discomfort (OR, 4.90; 95% CI, 2.00-12.01), and anxiety/depression (OR, 6.43; 95% CI, 2.16-19.12) were significantly high in female cancer survivors with low HGS. However, healthy controls showed no significant relationship between low HGS and QOL.

CONCLUSION

For cancer survivors, low HGS was associated with poor QOL in some domains. Strategies to increase muscle strength must be considered to improve the QOL of cancer survivors.

Upper Extremity Muscle Strength in Children With Unilateral Spastic Cerebral Palsy: A Bilateral Problem?

OBJECTIVE

The objective was to investigate whether muscle strength in the nonaffected and affected upper extremities (UEs) in children (7-12 years) with unilateral spastic cerebral palsy (USCP) differs from that in children with typical development (TD).

METHODS

A cross-sectional study design was used. Isometric arm strength (wrist flexion, wrist extension with flexed and extended fingers, elbow flexion/extension) was assessed in 72 children (mean age = 9.3 [SD = 1.9] years) with USCP, and isometric grip/pinch strength was assessed in 86 children (mean age = 9.3 [SD = 1.8] years) with USCP. Arm/grip/pinch strength was assessed in 120 children (mean age = 9.5 [SD = 1.7] years) with TD. Arm strength was measured with a hand-held dynamometer, and grip/pinch strength was measured with a calibrated, modified (digitized) grip dynamometer and a pinch meter. The nonaffected UE of children with USCP was compared with the preferred UE of children with TD because both sides represent the preferred UE. The affected UE was compared with the nonpreferred UE of children with TD, as both sides represent the nonpreferred UE.

RESULTS

In all measurements except for grip strength of the preferred UE, children with USCP were weaker than children with TD.

CONCLUSIONS

In children with USCP, muscle strength weakness exists in both UEs.

IMPACT

When unimanual or bimanual ability limitations are present in children with unilateral cerebral palsy, investigation of the muscle strength of the nonaffected UE should be part of the assessment.

Association between Relative Handgrip Strength and Dyslipidemia in Korean Adults: Findings of the 2014-2015 Korea National Health and Nutrition Examination Survey

BACKGROUND

Grip strength is a convenient method to measure muscle strength. Recently, relative handgrip strength (HGS) was recommended as a clinical predictor of metabolic health and disease, such as dyslipidemia, which is considered a risk factor for cardiovascular disease. The purpose of this study was to characterize the association between relative HGS and dyslipidemia.

METHODS

We included 6,027 adults (2,934 men, 3,093 women) aged 30-69 years who participated in the Korea National Health and Nutrition Examination Survey in 2014 and 2015. Relative HGS was obtained by dividing the HGS by body mass index. Complex sampling analysis was conducted to compare the general characteristics of participants according to the quartiles of relative HGS. Logistic regression analysis was used to examine the association between quartiles of relative HGS and dyslipidemia.

RESULTS

After adjustment for age, prevalence of diabetes mellitus, prevalence of hypertension, alcohol consumption, smoking status, exercise, income, and education level, relative HGS was inversely associated with dyslipidemia in both men and women. In multivariable logistic regression analysis, the odds ratios (95% confidence intervals) for dyslipidemia in quartiles 1, 2, and 3 relative to quartile 4 were 1.36 (1.00-1.83), 1.29 (0.98-1.70), 1.23 (0.95- 1.60) in men and 1.81 (1.30-2.50), 1.81 (1.32-2.47), 1.39 (1.07-1.81) in women, respectively.

CONCLUSION

Relative HGS was inversely associated with dyslipidemia risk in Korean adults. Muscle-strengthening exercise is recommended to enhance health outcomes.

Trajectories of Handgrip Strength and Their Associations with Mortality among Older Adults in Korea: Analysis of the Korean Longitudinal Study of Aging

BACKGROUND

Handgrip strength (HGS) is a good predictor of adverse health outcomes in later life. This prospective study aimed to investigate whether HGS trajectory patterns were associated with all-cause mortality among older adults in Korea.

METHODS

This study used the database of the 2006-2016 Korean Longitudinal Study of Aging. Study participants included 3,069 adults aged ≥65 years without a previous history of cancer. The trajectory model was developed to identify different homogeneous trajectory patterns of HGS according to study period. Cox proportional hazards models were then applied to investigate the association between HGS and all-cause mortality.

RESULTS

The survival probability according to HGS during the follow-up period decreased as base HGS weakened. We identified four distinct trajectory groups of HGS among men and three among women. The risk of mortality increased as the HGS of both males and females decreased. Compared with the highest HGS group, the adjusted hazard ratios for all-cause mortality of the lowest, lower-mid, and upper-mid HGS groups among males were 3.46 (95% confidence interval [CI], 2.17-6.69), 2.26 (95% CI, 1.47-3.48), and 1.58 (95% CI, 1.07-2.32). Those of the low and mid HGS groups among females were 2.69 (95% CI, 1.39-5.21) and 1.97 (95% CI, 1.05-3.69).

CONCLUSION

The faster HGS declined over time, the greater the all-cause mortality risk increased compared with the slowly decreasing or maintained HGS groups among men and women. HGS measurement among older adults will be helpful in assessing their health statuses and pre-assessing disease-associated morbidity.

Association of Hand Grip Strength and Cardiometabolic Markers in Korean Adult Population: The Korea National Health and Nutrition Examination Survey 2015-2016

Background

Muscle strength has been suggested as a cardiovascular marker. The aim of this study was to examine the associations between hand grip strength and biomarkers of cardiovascular disease in the Korean population.

Methods

A total of 9,083 participants aged 20–80 years from Korea National Health and Nutrition Examination Survey 2015–2016 were investigated.

Results

Among men, both relative and dominant hand grip strength showed a positive association with diastolic blood pressure in those aged 65–80 years (95% confidence interval, P-value of dominant and relative hand grip strength: β=0.06, 0.01; P<0.05). Among women, relative and dominant hand grip strength showed a positive relationship to diastolic blood pressure in those aged 20–64 years (β=0.06, 0.01; P<0.001). Body mass index was positively associated with dominant hand grip strength in younger women (β=0.18, P<0.05), whereas it was positively associated with relative hand grip strength in all sex and age groups. High-sensitivity C-reactive protein showed a negative association with relative and dominant hand grip strength in all women, although the same association was observed only in younger men. Diabetes was inversely related to hand grip strength in younger women and men.

Conclusion

Increased hand grip strength may be associated with lower C-reactive protein in women and with less risk of diabetes in the Korean adult population. Further prospective studies are needed for the determination of causality between cardiometabolic markers and hand grip strength.

Relationship between Sedentary Time and Handgrip Strength in Healthy Korean Women: Korea National Health and Nutrition Examination Survey 2014-2016

Background

This study aimed to examine the association between sitting time and handgrip strength in healthy Korean women.

Methods

A total of 5,437 participants were included from the Korea National Health and Nutrition Examination Survey 2014–2016. The overall daily sitting time was estimated using health interview surveys, and handgrip strength was assessed using a digital hand dynamometer. The relationship between sitting time and handgrip strength was calculated with a weighted analysis of covariance after adjusting for confounding variables.

Results

Participants in each age group (19–39, 40–64, ≥65 years) were divided into three categories according to sitting time: ≤5, 6–9, and ≥10 h/d. The handgrip strength tended to decrease as sitting time increased after adjusting for age, body mass index, alcohol intake, cigarette smoking, resistance exercise, aerobic physical activity, household income, education level, hypertension, diabetes mellitus, dyslipidemia, and depression in all age groups (all P<0.001).

Conclusion

We observed the inverse relationship between sitting time and handgrip strength in healthy Korean women.

Test-Retest Reliability of Handgrip Strength as an Outcome Measure in Patients With Symptoms of Shoulder Impingement Syndrome

OBJECTIVE

The purpose of this study was to investigate the degree of test-retest reliability of grip strength measurement using a hand dynamometer in patients with shoulder impingement syndrome.

METHODS

A total of 19 patients (10 women and 9 men; mean ± standard deviation age, 33.2 ± 12.9 years; range 18-59 years) with shoulder impingement syndrome were measured using a hand dynamometer by the same data collector in 2 different testing sessions with a 7-day interval. During each session, patients were encouraged to exert 3 maximal isometric contractions on the affected hand and the mean value of the 3 efforts (measured in kilogram-force [Kgf]) was used for data analysis. The intraclass correlation coefficient (ICC_2,1) as well as the standard error of measurement (SEM) and Bland-Altman plot were used to estimate the degree of test-retest reliability and the measurement error, respectively.

RESULTS

Grip strength data analysis revealed an ICC_2,1 score of 0.94, which, based on the Shrout classification, is considered as excellent test-retest reliability of grip strength measurement. The small values of SEMs reported in both sessions (SEM₁, 2.55 Kgf; SEM₂, 2.39 Kgf) and the small width of the 95% limits of agreement in the Bland-Altman plot (ranging from -7.39 Kgf to 7.03 Kgf) reflected the measurement precision and the narrow variation of the differences during the 2 testing sessions.

CONCLUSIONS

Results from this study identified excellent test-retest reliability of grip strength measurement in shoulder impingement syndrome, indicating its potential use as an outcome measure in clinical practice.

Frailty and Access to Kidney Transplantation

BACKGROUND AND OBJECTIVES

Frailty, a syndrome distinct from comorbidity and disability, is clinically manifested as a decreased resistance to stressors and is present in up to 35% of patient with ESKD. It is associated with falls, hospitalizations, poor cognitive function, and mortality. Also, frailty is associated with poor outcomes after kidney transplant, including delirium and mortality. Frailty is likely also associated with decreased access to kidney transplantation, given its association with poor outcomes on dialysis and post-transplant. Yet, clinicians have difficulty identifying which patients are frail; therefore, we sought to quantify if frail kidney transplant candidates had similar access to kidney transplantation as nonfrail candidates.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We studied 7078 kidney transplant candidates (2009-2018) in a three-center prospective cohort study of frailty. Fried frailty (unintentional weight loss, grip strength, walking speed, exhaustion, and activity level) was measured at outpatient kidney transplant evaluation. We estimated time to listing and transplant rate by frailty status using Cox proportional hazards and Poisson regression, adjusting for demographic and health factors.

RESULTS

The mean age was 54 years (SD 13; range, 18-89), 40% were women, 34% were black, and 21% were frail. Frail participants were almost half as likely to be listed for kidney transplantation (hazard ratio, 0.62; 95% confidence interval, 0.56 to 0.69; P<0.001) compared with nonfrail participants, independent of age and other demographic factors. Furthermore, frail candidates were transplanted 32% less frequently than nonfrail candidates (incidence rate ratio, 0.68; 95% confidence interval, 0.58 to 0.81; P<0.001).

CONCLUSIONS

Frailty is associated with lower chance of listing and lower rate of transplant, and is a potentially modifiable risk factor.

The Relationship between Handgrip Strength and Cognitive Function in Elderly Koreans over 8 Years: A Prospective Population-Based Study Using Korean Longitudinal Study of Ageing

Background

Decreased physical performance, such as weakened handgrip strength and cognitive decline, is associated with disability and premature death in old age. We investigated the association between handgrip strength and cognitive impairment in Korean elderly adults with normal cognitive function.

Methods

This prospective study used the database from the Korean Longitudinal Study of Ageing. The participants included 2,378 adults aged 65 years or older with normal cognitive function (Korean Mini-Mental Status Evaluation [K-MMSE] score ≥21). Using a mixed-effects model, we examined the associations at baseline and over an 8-year follow-up period between handgrip strength and K-MMSE score. We investigated handgrip strength as a predictor of change in cognitive function.

Results

This study included 1,138 women (mean maximum handgrip strength 19.2 kg, mean K-MMSE score 25.1) and 1,240 men (mean maximum handgrip strength 30.7 kg, mean MMSE score 26.2). The baseline handgrip strength was positively associated with the baseline K-MMSE score (b=0.18, P<0.001). Using a mixed-effects model, we found that higher handgrip strength at baseline can predict MMSE scores positively over time (b=0.14, P<0.001) and the change of handgrip strength over time was a predictor of high MMSE scores over the study period (b=0.01, P<0.01).

Conclusion

We observed significant associations between baseline handgrip strength and baseline and change of cognition, as well as the longitudinal influence of handgrip strength on the change of cognitive function in elderly Korean adults with normal cognitive function.

Low Grip Strength and Prediabetes in Normal-Weight Adults

INTRODUCTION

Detection of prediabetes is an important step in diabetes prevention in primary care. Risk stratification of healthy-weight individuals for detection of prediabetes is necessary to avoid missed opportunities for diabetes prevention.

METHODS

Using data from the 2011 to 2012 National Health and Nutrition Examination Survey, we studied the relationship between combined handgrip strength, a proxy for lean muscle mass, and prediabetes among adults aged ≥20 years without diagnosed or undiagnosed diabetes who had a healthy body mass index (18.5-24.9 kg/m(2); unweighted n = 1340, weighted n = 58,360,690). Prediabetes was defined as having a glycohemoglobin level between 5.7% and 6.4%.

RESULTS

Of the healthy-weight adults, 20.5% had prediabetes. Combined mean grip strength was lower for individuals with prediabetes than those with normoglycemia in the full sample (63.8 vs 70.9 kg; P = .004). Similar results were seen among both men (87.9 vs 82.1 kg; P = .03) and women (51.8 vs 56.5 kg; P = .001) in subgroup analysis.

CONCLUSIONS

Grip strength is associated with prediabetes among healthy-weight US adults. Grip strength may have utility as an indicator for screening healthy-weight individuals for prediabetes.

Hand-grip strength does not correlate with treatment-related weight loss in patients with head and neck cancer

BACKGROUND

Hand-grip strength has been shown to be a reliable predictor of health outcomes. However, evidence supporting its use as an indicator of nutritional status is inconsistent. This study investigated its use in monitoring nutritional status in patients with head and neck cancer.

METHODS

A prospective audit of patients treated for head and neck cancer was undertaken at four centres over a three-month period in 2009. Nutritional outcomes were collected at 3, 6 and 12 months, and the data were statistically analysed.

RESULTS

Data from 114 patients showed that mean weight, but not hand-grip strength, fell significantly at 3, 6 and 12 months post-treatment (p < 0.003 vs p < 0.126).

CONCLUSION

A fall in weight does not coincide with a drop in hand-grip strength in patients receiving treatment for head and neck cancer. Hand-grip strength may therefore not be of benefit in the nutritional assessment of these patients and should not be part of routine assessment.

Immediate and delayed effects of forearm kinesio taping on grip strength

BACKGROUND

Due to the fundamental role of gripping in most upper limb activities, grip strength promotion is a chief goal in the treatment of patients with upper limb musculoskeletal disorders. Kinesio taping is a novel and effective therapeutic technique believed to facilitate muscle contraction through stimulating mechanoreceptors and increasing the sensory feedback around the taped region.

OBJECTIVES

The present study aimed to identify the best region (flexor, extensor and flexor/extensor regions) and time (immediate, 0.5, 1, 1.5, and 2 hours) of forearm Kinesio taping to obtain the maximum improvement in grip strength.

MATERIALS AND METHODS

In this longitudinal study, 40 healthy men and women (the mean age of 22.3 ± 2.19 years) were selected among students of Shahid Beheshti University of Medical Sciences, Tehran, Iran by simple, nonrandom sampling method. A dynamometer was used to measure grip strength immediately and every 30 minutes during the two hours after I-shaped application of tape (with 50% stretch) to the flexor, extensor, and flexor/extensor forearm muscles.

RESULTS

Grip strength was significantly increased in various muscle groups for males (P = 0.002) and females (P = 0.000) of the forearm and at different intervals for males (P = 0.000) and females (P = 0.000). Moreover, in both men and women, tape application to the extensor region provided greater grip strength compared to taping of the flexor and flexor/extensor regions (P = 0.000 for both). Furthermore, the maximum increase in grip strength were 0.5 (10.8% increase, P = 0.001) and 1.5 h (23.9% increase, P = 0.000) after taping in males and females, respectively.

CONCLUSIONS

Taping the extensor region of forearm is recommended to achieve higher grip strength. Although grip strength increased at a slower pace in females than males, the final values were higher in women.

Test-retest reliability of handgrip strength measurement using a hydraulic hand dynamometer in patients with cervical radiculopathy

OBJECTIVE

The purpose of this study was to evaluate the test-retest reliability of handgrip strength measurement using a hydraulic hand dynamometer in patients with cervical radiculopathy (CR).

METHODS

A convenience sample of 19 participants (14 men and 5 women; mean ± SD age, 50.5 ± 12 years) with CR was measured using a Jamar hydraulic hand dynamometer by the same rater on 2 different testing sessions with an interval of 7 days between sessions. Data collection procedures followed standardized grip strength testing guidelines established by the American Society of Hand Therapists. During the repeated measures, patients were advised to rest their upper limb in the standardized arm position and encouraged to exert 3 maximum gripping efforts. The mean value of the 3 efforts (measured in kilogram force [Kgf]) was used for data analysis. The intraclass correlation coefficient, SEM, and the Bland-Altman plot were used to estimate test-retest reliability and measurement precision.

RESULTS

Grip strength measurement in CR demonstrated an intraclass correlation coefficient of 0.976, suggesting excellent test-retest reliability. The small SEM in both testing sessions (SEM1, 2.41 Kgf; SEM2, 2.51 Kgf) as well as the narrow width of the 95% limits of agreements (95% limits of agreement, -4.9 to 4.4 Kgf) in the Bland-Altman plot reflected precise measurements of grip strength in both occasions.

CONCLUSIONS

Excellent test-retest reliability for grip strength measurement was measured in patients with CR, demonstrating that a hydraulic hand dynamometer could be used as an outcome measure for these patients.

Effects of taping on pain, grip strength and wrist extension force in patients with tennis elbow

Background

Tennis elbow (TE) is a common musculotendinous degenerative disorder of the extensor origin at the lateral humeral epicondyle. Different modes of treatment are used for management of tennis elbow.

Objectives

This study investigated the effect of the taping technique (TT) on pain, grip strength and wrist extension force in treatment of tennis elbow.

Patients and Methods

Thirty patients (16 men /14 women with a mean age of 32.2 years) with tennis elbow of their dominant arm participated in this study. Outcome measures were assessment of pain at the lateral aspect of the elbow, grip strength and wrist extension force before and five to ten minutes after application of elbow tape on the affected and unaffected arms. A Visual Analog Scale was used to assess pain. A dynamometer and a hand-held dynamometer were used for evaluation of grip strength and wrist extension force, respectively.

Results

Among the variables, significant differences were found in wrist extension forces between effected and unaffected arms (P = 0.02). Changes in grip strength showed statically significant improvements in the affected arm compared to the unaffected arm (P = 0.03). Also, in assessment of pain at the lateral epicondyle, the mean change between affected and unaffected arms was significant, with P = 0.001.

Conclusions

The taping technique, as applied in this study demonstrates an impressive effect on wrist extension force and grip strength of patients with TE. Elbow taping also reduces pain at the lateral aspect of the elbow in these patients.

Correlations of Handgrip Strength with Selected Hand-Arm-Anthropometric Variables in Indian Inter-university Female Volleyball Players

Purpose

The purpose of this study was to estimate the dominant handgrip strength and its correlations with some hand and arm anthropometric variables in 101 randomly selected Indian inter-university female volleyball players aged 18-25 years (mean age 20.52±1.40) from six Indian universities.

Methods

Three anthropometric variables, i.e. height, weight, BMI, two hand anthropometric variables, viz. right and left hand width and length, four arm anthropometric variables, i.e. upper arm length, lower arm length, upper extremity length, upper arm circumference and dominant right and non-dominant handgrip strength were measured among Indian inter-university female volleyball players by standard anthropometric techniques.

Results

The findings of the present study indicated that Indian female volleyball players had higher mean values in eleven variables and lesser mean values in two variables than their control counterparts, showing significant differences (P<0.032-0.001) in height (t=2.63), weight (t=8.66), left hand width (t=2.10), left and right hand length (t=9.99 and 10.40 respectively), right upper arm length (t=8.48), right forearm length (t=5.41), dominant (right) and non-dominant (left) handgrip strength (t=9.37 and 6.76 respectively). In female volleyball players, dominant handgrip strength had significantly positive correlations (P=0.01) with all the variables studied.

Conclusion

It may be concluded that dominant handgrip strength had strong positive correlations with all the variables studied in Indian inter-university female volleyball players.