Comparison of Jamar and Bodygrip Dynamometers for Handgrip Strength Measurement

Reliability and validity of the hand-held dynamometer "NOD": a new instrument for assessment of isometric grip strength

INTRODUCTION

Hand grip strength (HGS) is an important measure in a physiotherapy assessment and for this purpose it is necessary to have valid and reliable instruments to measure it. In this study we aimed at investigating the reliability, validity, and agreement of the new hand-held dynamometer NOD (OT-Bioelettronica, To-Italy) compared to Jamar® hydraulic dynamometer (JD), the gold standard.

METHODS

Fifty healthy subjects were selected; 9 trials for the dominant hand and 9 trials for the non-dominant hand were administrated to each of them: 3 trials of HGS with the JD in rung #3, 3 trials with the JD-adapted-grip (like the NOD one), and 3 trials with NOD. To verify the reliability of NOD, the Intraclass Correlation Coefficient (ICC 3,1) was calculated with a mixed effects model with the addition of adjustment variables (age, gender, dominant / non-dominant limb, trials). The model used single HGS measurements to estimate variance components, so reflecting both degree of correspondence and agreement among devices. To assess concurrent validity NOD was compared to the "gold standard" JD, in terms of ICCs and through Pearson correlation. The agreement between the methods of measurement was calculated with the Limits of Agreement (LoA) and the plots of Bland-Altman.

RESULTS

All ICCs show high inter-reliability; the results are very similar for both dynamometers. The value of the adjusted ICC of NOD was 0.90. For validity, Pearson correlations of NOD towards JD and JD-adapted-grip were high (r = 0.87 and 0.88). However, the LoA and the plots of Bland-Altman demonstrated that there is no agreement between NOD and JD and between NOD and JD-adapted-grip, with NOD showing lower mean scores than JD.

CONCLUSIONS

NOD is a reliable and valid instrument for HGS. However, even if it cannot be considered interchangeable with JD because there is no agreement between them in free-living adults, NOD is easier to carry than other dynamometers, it has a Bluetooth® connection with a free App and it is a multi-purpose tool that should be considered both in daily practice and in clinical settings.

Nepal Family Cohort study: a study protocol

INTRODUCTION

The Nepal Family Cohort study uses a life course epidemiological approach to collect comprehensive data on children's and their parents' environmental, behavioural and metabolic risk factors. These factors can affect the overall development of children to adulthood and the onset of specific diseases. Among the many risk factors, exposure to air pollution and lifestyle factors during childhood may impact lung development and function, leading to the early onset of respiratory diseases. The global incidence and prevalence of respiratory diseases are rapidly increasing, with the rate of increase in Nepal being the highest. Although the cohort will primarily focus on respiratory health, other health outcomes such as cardiovascular, metabolic and mental health will be assessed to provide a comprehensive overall health assessment. All other health outcomes are self-reported following doctor diagnosis. Some of these health outcomes will be quality controlled during the follow-up by measuring disease specific markers. Our cohort study will likely provide evidence of risk factors and policy recommendations.

METHODS AND ANALYSIS

Using a life-course epidemiology approach, we established a longitudinal study to address the determinants of lung health and other health outcomes from childhood to adulthood. The baseline data collection (personal data anonymised) was completed in April 2024, and 16 826 participants (9225 children and 7601 parents) from 5829 families were recruited in different geographical and climate areas (hills and plains) of Nepal. We plan to follow up all the participants every 2-3 years.Descriptive analysis will be used to report demographic characteristics and compare rural and semi-urban regions. A linear regression model will assess the association between air pollution, particularly household air pollution (HAP) exposure, and other lifestyle factors, with lung function adjusted for potential confounders. A two-stage linear regression model will help to evaluate lung development based on exposure to HAP.

ETHICS

Ethical approval was obtained from the Nepal Health Research Council, Kathmandu, Nepal, and McMaster University, Hamilton, Canada. Permissions were obtained from two municipalities where the study sites are located. Parents provided signed informed consent and children their assent.

DISSEMINATION

Findings will be disseminated through traditional academic pathways, including peer-reviewed publications and conference presentations. We will also engage the study population and local media (ie, research blogs and dissemination events) and prepare research and policy briefings for stakeholders and leaders at the local, provincial and national levels.

Are accelerometer-measured sitting and physical activity times associated with muscle mass and strength in healthy young adults in the UAE?

Background

A high prevalence of obesity, sedentary behavior, and physical inactivity could affect muscle mass and strength in young adults in the United Arab Emirates (UAE). Therefore, we investigated the association of sex, body mass index (BMI), and accelerometer-measured sitting and physical activity (PA) times with skeletal muscle mass index (SMI), hand grip, and thigh muscle strength in healthy young adults in the UAE.

Methods

In this cross-sectional study, 156 healthy young adults (age 21.68 ± 3.01 years, BMI 25.40 ± 4.79 kg/m2, 52.6 % women) were included. BMI and muscle mass were recorded using a bioelectrical impedance analyzer. Maximum hand grip strength and thigh muscle torque were assessed using the Jamar-smart hand-dynamometer and Biodex System-4-Pro, respectively. Participants wore a triaxial Fibion accelerometer on their anterior thigh for >10 h per day for 4-7 days to measure their sitting and PA times. Multiple linear regression analyses were used.

Results

Participants spent most of their time sitting (11.37 ± 1.10 h), followed by standing (2.92 ± 0.86 h), walking (1.58 ± 0.55 h), and vigorous intensity PA (4.79 ± 5.85 min) per 16-h day. Sex (p < 0.001) and BMI (p < 0.001) were negatively associated with all muscle mass and strength variables. Men had more muscle mass and strength than women. As BMI increased, muscle mass and muscle strength decreased. Accelerometer-measured sitting and walking times were negatively associated with concentric hamstrings (p = 0.044) and quadriceps torques (p = 0.031), respectively.

Conclusion

Sex, BMI, and accelerometer-measured sitting and walking times were associated with muscle mass and/or muscle strength in healthy young adults. Women and those with a high BMI need interventions to improve their muscle mass and strength. The paradox regarding the association of PA with muscle mass and strength in younger adults may be due to possible influences from other factors (e.g., resistance training, dietary intakes, etc.) superseding that of accelerometer-measured PA.

Linguistic, visuospatial, and kinematic writing characteristics in cognitively impaired patients with beta-amyloid deposition

Introduction

Beta-amyloid (Aβ) deposition, a hallmark of Alzheimer's disease (AD), begins before dementia and is an important factor in mild cognitive impairment (MCI). Aβ deposition is a recognized risk factor for various cognitive impairments and has been reported to affect motor performance as well. This study aimed to identify the linguistic, visuospatial, and kinematic characteristics evident in the writing performance of patients with cognitive impairment (CI) who exhibit Aβ deposition.

Methods

A total of 31 patients diagnosed with amnestic mild cognitive impairment (aMCI) with Aβ deposition, 26 patients with Alzheimer's-type dementia, and 33 healthy control (HC) participants without deposition were administered tasks involving dictation of 60 regular words, irregular words, and non-words consisting of 1-4 syllables. Responses from all participants were collected and analyzed through digitized writing tests and analysis tools.

Results

In terms of linguistic aspects, as cognitive decline progressed, performance in the dictation of irregular words decreased, with errors observed in substituting the target grapheme with other graphemes. The aMCI group frequently exhibited corrective aspects involving letter rewriting during the task. In terms of visuospatial aspects, the AD group displayed more errors in grapheme combination compared to the HC group. Lastly, in the kinematic aspects, both the aMCI group and the AD group exhibited slower writing speeds compared to the HC group.

Discussion

The findings suggest that individuals in the CI group exhibited lower performance in word dictation tasks than those in the HC group, and these results possibly indicate complex cognitive-language-motor deficits resulting from temporal-parietal lobe damage, particularly affecting spelling processing. These results provide valuable clinical insights into understanding linguistic-visuospatial-kinematic aspects that contribute to the early diagnosis of CI with Aβ deposition.

Comparison of four screening methods for sarcopenia among community-dwelling older adults: A diagnostic accuracy study

This study aimed to compare the diagnostic values of SARC-F (strength, assistance with walking, rising from a chair, climbing stairs, and falls), SARC-Calf (SARC-F combined with calf circumference), CC (calf circumference), and the Yubi-wakka (finger-ring) test for screening for sarcopenia in community-dwelling older adults. The Asian Working Group for Sarcopenia (AWGS) 2019 criteria were used as a standard reference. A total of 209 participants were enrolled, and 40.7% were identified as sarcopenia. The sensitivity, specificity, and AUC were respectively 54.1%, 70.2%, and 0.687 for SARC-F; 76.5%, 73.4% and 0.832 for SARC-calf, 86.7%, 82.4%, and 0.906 for CC in men, and 85.5%, 63.3%, and 0.877 for CC in women. Relative to the "bigger," a significant association between sarcopenia and the Yubi-wakka test ("just fits" OR: 4.1, 95% CI: 1.57-10.98; "small" OR: 27.5, 95% CI: 10.14-74.55) was observed. The overall accuracy of CC was better than SARC-Calf for sarcopenia screening.

Portable Digital Monitoring System for Sarcopenia Screening and Diagnosis

Sarcopenia is a well-known highly prevalent muscle disease that severely impairs overall physical performance in elders, inducing a massive health-related economic burden. The widespread screening, diagnosis and treatment of sarcopenia are pivotal to restrain the disease progression and constrain its societal impact. Simple-to-use, portable, and reliable methods to evaluate sarcopenia are scarce, and sarcopenia-related assessments are typically done in several time-consuming stages. This study presents a portable digital system that enables a simple and intuitive method to evaluate sarcopenia-based on the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) algorithm-including the four Find-Assess-Confirm-Severity (FACS) steps. The system comprises a mobile application (app); two wireless devices: a dynamometer (Gripwise) and a skinfold caliper (Lipowise); and a back-end website. To find cases, the SARC-F questionnaire is applied. To assess sarcopenia, the handgrip strength and the sit-to-stand tests are performed with the Gripwise and an application-embedded stopwatch, respectively. To confirm cases, anthropometric measures are performed, and muscle quantity is estimated with Lipowise. Finally, to assess severity, the app stopwatch grants the gait speed test application, evaluating physical performance. This step-by-step sarcopenia assessment results in a final grading according to the cut-off points of the EWGSOP2 criteria. All data is automatically encrypted and exported into a GDPR-compliant cloud platform, in which healthcare professionals can access and monitor their patients through the internet.

A Prospective Evaluation of Grip Strength Comparing a Low-Tech Method to Dynanometry in Preoperative Surgical Patients and Weak Intensive Care Patients

Objective. Grip strength testing offers a mechanism to identify patients in whom frailty might be present, discriminate between robust elderly and vulnerable younger patients, and can be used as a tool to track changes in muscle bulk over the course of an inpatient stay. We compared gold-standard quantitative grip strength measurement to a low-tech alternative, a manual bedside sphygmomanometer. Design. Under supervision, subjects performed hand-grip strength testing with each instrument. A mean score is calculated from three measurements on the dominant and nondominant hand. Setting. Testing was performed in a tertiary centre in Perth, Western Australia, in both outpatient clinics and intensive care units. Participants. 51 adult pre-operative surgical outpatients were assessed, alongside 20 intensive care inpatients identified as being weak. Main outcome measures. A statistical correlation between the two measures was evaluated. Feasibility, safety, and convenience were also assessed in outpatient and bedside settings. Results. Highly correlated results in both tertiary surgical outpatients (rs = 0.895, $p\le 0.001$ , N = 102; r (100) = 0.899, $p\le 0.001$ ) and weak intensive care patients (rs = 0.933, $p\le 0.001$ , N = 39 r (37) = 0.935, $p\le 0.001$ ) Conclusions. Modifying a manual bedside sphygmomanometer to measure grip strength is feasible and correlates well with a formal dynamometer in preadmission surgical patients and weak patients in the intensive care unit. The use of an existing, safe, and available device removes barriers to the measurement of weakness in patients and may encourage uptake of objective measurement in multiple settings.

GripAble: An accurate, sensitive and robust digital device for measuring grip strength

Introduction

Grip strength is a reliable biomarker of overall health and physiological well-being. It is widely used in clinical practice as an outcome measure. This paper demonstrates the measurement characteristics of GripAble, a wireless mobile handgrip device that measures grip force both isometrically and elastically-resisted for assessment and training of hand function.

Methods

A series of bench tests were performed to evaluate GripAble's grip force measurement accuracy and sensitivity. Measurement robustness was evaluated through repeated drop tests interwoven with error verification test phases.

Results

GripAble's absolute measurement error at the central position was under 0.81 and 1.67 kg (95^th percentiles; N = 47) when measuring elastically and isometrically, respectively, providing similar or better accuracy than the industry-standard Jamar device. Sensitivity was measured as 0.062 ± 0.015 kg (mean ± std; 95^th percentiles: [0.036, 0.089] kg; N = 47), independent of the applied force. There was no significant performance degradation following impact from 30 drops from a height >1.5 m.

Conclusion

GripAble is an accurate and reliable grip strength dynamometer. It is highly sensitive and robust, which in combination with other novel features (e.g. portability, telerehabilitation and digital data tracking) enable broad applicability in a range of clinical caseloads and environments.

Active vegetarians show better lower limb strength and power than active omnivores

Vegetarian diets have become popular among athletes and active individuals and can have advantages for physical performance, but the results are still conflicting regarding muscle strength and power. The aim of this study was to evaluate the diet and physical performance of vegetarians through tests of dynamic, isometric, and relative strength; muscle power; and aerobic capacity. In this cross-sectional study, 32 vegetarians and 26 omnivores, who were physically active, were evaluated for the Healthy Eating Index and performance tested back squat, handgrip strength, isometric deadlift strength, jump with countermovement, and maximum aerobic speed (MAS). Improved diet quality (63.24 ± 14.40 vs. 54 ± 16.80, p<0.05), greater relative strength (1.03 ± 0.23 vs. 0.91 ± 0.12, p<0.05), and greater jump height (43.77 ± 9.91 vs. 38.45 ± 8.92, p<0.05) were found among vegetarians. No difference was seen in MAS (13.5 ± 2 vs. 11 ± 3, p>0.05) or isometric strength of upper limbs (77 ± 29 vs. 70 ± 50, p>0.05) and lower limbs (89 ± 41 vs. 97 ± 50, p>0.05). Thus, we conclude that vegetarians and omnivores show similar performance in strength and aerobic capacity, but in our sample, vegetarians show higher levels of relative strength and power.

Modernising grip dynamometry: Inter-instrument reliability between GripAble and Jamar

INTRODUCTION

Maximum grip strength (MGS) is a reliable biomarker of overall health and physiological well-being. Therefore, an accurate and reliable measurement device is vital for ensuring the validity of the MGS assessment. This paper presents GripAble, a mobile hand grip device for the assessment of MGS. GripAble's performance was evaluated using an inter-instrument reliability test against the widely used Jamar PLUS+ dynamometer.

METHODS

MGS data from sixty-three participants (N = 63, median (IQR) age = 29.0 (29.5) years, 33 M/30 F) from both hands using GripAble and Jamar PLUS+ were collected and compared. Intraclass correlation (ICC), regression, and Bland and Altman analysis were performed to evaluate the inter-instrument reliability and relationship in MGS measurements between GripAble and Jamar PLUS+ .

RESULTS

GripAble demonstrates good-to-excellent inter-instrument reliability to the Jamar PLUS+ with ICC3,1 = 0.906 (95% CI [0.87-0.94]). GripAble's MGS measurement is equivalent to 69% (95% CI [0.67-0.71]%) of Jamar PLUS+'s measurement. There is a proportional difference in mean MGS between the two devices, with the difference in MGS between GripAble and Jamar PLUS+ increasing with MGS.

CONCLUSION

The GripAble is a reliable tool for measuring grip strength. However, the MGS readings from GripAble and Jamar PLUS+ should not be interchanged for serial measurements of the same patient, nor be translated directly from one device to the other. A new normative MGS data using GripAble will be collected and accessed through the software for immediate comparison to age and gender-matched subpopulations.

Strength Training Intensity and Volume Affect Performance of Young Kayakers/Canoeists

Purpose

The aim of this study was to compare the effects of moderate intensity, low volume (MILV) vs. low intensity, high volume (LIHV) strength training on sport-specific performance, measures of muscular fitness, and skeletal muscle mass in young kayakers and canoeists.

Methods

Semi-elite young kayakers and canoeists (N = 40, 13 ± 0.8 years, 11 girls) performed either MILV (70–80% 1-RM, 6–12 repetitions per set) or LIHV (30–40% 1-RM, 60–120 repetitions per set) strength training for one season. Linear mixed-effects models were used to compare effects of training condition on changes over time in 250 and 2,000 m time trials, handgrip strength, underhand shot throw, average bench pull power over 2 min, and skeletal muscle mass. Both between- and within-subject designs were used for analysis. An alpha of 0.05 was used to determine statistical significance.

Results

Between- and within-subject analyses showed that monthly changes were greater in LIHV vs. MILV for the 2,000 m time trial (between: 9.16 s, SE = 2.70, p < 0.01; within: 2,000 m: 13.90 s, SE = 5.02, p = 0.01) and bench pull average power (between: 0.021 W⋅kg^–1, SE = 0.008, p = 0.02; within: 0.010 W⋅kg^–1, SE = 0.009, p > 0.05). Training conditions did not affect other outcomes.

Conclusion

Young sprint kayakers and canoeists benefit from LIHV more than MILV strength training in terms of 2,000 m performance and muscular endurance (i.e., 2 min bench pull power).

An Attempt to Identify Meaningful Descriptors of Handgrip Strength Using a Novel Prototype: Preliminary Study

Handgrip strength (HGS) is an indicator of muscle condition and general health wellbeing. Usually, instruments measuring handgrip strength only identify its maximum value. This preliminary study is focused on identifying force vs. time parameters which could contribute to better describe individual strength. They were obtained during a Handgrip strength test of 15 s in a sample group of 94 university students. The tests were conducted with a smart multifunction novel prototype dynamometer, named BodyGrip. Mean values of quantities related to the ability to develop and to maintain strength in percentage of maximum handgrip strength, were extracted from the force vs time profile. Contrary to maximum HGS, such quantities were found to be independent of the participant’s anthropometric characteristics. Individual comparisons based on those quantities are therefore not affected by the anthropometric characteristics. It was possible to identify individuals, differing on the development of HGS. Results suggest that the functionality of the BodyGrip tool enables a more thorough characterization of the time profile of the Handgrip strength that might influence the knowledge of the muscle functions, such as power development and endurance.

Concurrent validity of handgrip strength between the jamar and bulb dynamometers in women with rheumatoid arthitis

Abstract Introduction: Rheumatoid arthritis (RA) is a progressive disease that causes deformation and constant joint damage. Handgrip strength (HGS) has been used by several health professionals in clinical practice as a mechanism for assessing muscle strength and overall performance. Objective: To perform the concordance analysis of handgrip strength measurements using a pneumatic dynamometer (Bulb) and a hydraulic dynamometer (Jamar) in women with rheumatoid arthritis. Method: The HGS measurements by the two dynamometers followed the norms of the American Society of Hand Therapists. The concordance between measurements was performed by the Bland-Altman method. Significance level was 5%. Results: In total, 41 women (60.63 ± 8.35 years) participated in the study. Analysis showed that the measures between the two dynamometers were not concordant (bias = 9.04, p < 0.01), there was a linear relationship between the difference of the measures and the mean (r = 0.73, p < 0.01), and the limits of agreement were very extensive (−2.74 to 20.81). Conclusion: Assuming that the rheumatoid arthritis compromises the hands, with a consequent decrease in HGS, further exploration of the subject is suggested in future studies to define the best measure for clinical practice at the different levels of health care. However, since there are many different dynamometers, we suggest to better explore the agreement between the measurements obtained by them in populations under different conditions.

Association between Colorectal Adenoma and Hand Grip Strength in the Elderly

Background

Obesity is known as an important risk factor for colorectal adenoma. However, for the elderly with changes in body composition, reduced muscle, and increased fat, the body mass index (BMI), one of the most commonly used indicators of obesity, is limited in predicting a link to colorectal cancer. This study aimed to investigate the relationship between colorectal adenoma and grip strength that can predict muscle reduction in the elderly.

Methods

This study included 262 participants aged ≥65 years who underwent medical examination between June 2015 and August 2018. The control group comprised participants with normal findings or hyperplasia and other benign lesions, except adenoma on colonoscopy, whereas the adenoma group consisted of participants with more than one adenoma. Grip strength was alternately measured twice for each hand using a hydraulic dynamometer.

Results

The grip strength was statistically lower in the adenoma group than in the control group among women (P=0.042). For both sexes, grip strength was significantly lower in participants with ≥5 adenomas than in those with <5 adenomas (P=0.021, P=0.007). Similarly, men with large adenomas (≥7 mm) exhibited significantly lower grip strength than did those with small adenomas (<7 mm) (P=0.004). Even after correction for age, BMI, smoking status, alcohol consumption, exercise, insulin resistance, hypertension, and diabetes, the negative correlation between grip strength and number of adenomas among men and women remained (P=0.034, P=0.019).

Conclusions

A significant relationship between hand grip strength and number of colorectal adenomas was noted.