Reliability and Validity of Individual Finger Flexor Strength Measurement Using the Martin Vigorimeter.

Purpose: This study aimed to estimate the intra- and inter-rater reliability of the JTECH computerized, wireless apparatus and its validity (compared to established devices) for measurements of maximal shoulder isometric strength and handgrip strength among healthy adults with no shoulder pathology. Methods: Twenty healthy young adults had shoulder strength tested with JTECH and Micro-FET2 hand-held dynamometers, and the handgrip strength was tested using JTECH and Jamar handgrip dynamometers. Assessments were performed by the same rater to determine intra-rater reliability and convergent validity, at least two days apart, while on a third visit, the other rater performed measures to determine inter-rater reliability. Results: The JTECH computerized, wireless devices demonstrated good to excellent intra-rater reliability (ICCs (2,1)=0.78-0.97) and inter-rater reliability for strength measures (ICCs (2,1)=0.76-0.95). The JTECH computerized device compared to the Micro-FET2 hand-held dynamometer showed substantial concurrent validity for shoulder flexion (R2=0.87), extension (R2=0.87), abduction (R2=0.88), and adduction (R2=0.85). Substantial concurrent validity was shown for the JTECH computerized device and Jamar handgrip dynamometers (R2=0.92). Conclusions: The JTECH computerized, wireless devices demonstrated high intra- and inter-rater reliability and substantial concurrent validity for shoulder isometric strength and handgrip strength in healthy adults.

Recently, subclinical aspiration has been identified in approximately 30% of community-dwelling older adults. Given that the tongue is a key component of the safe swallow, we hypothesized healthy older adults who aspirate will generate less tongue strength than adults who do not aspirate. Furthermore, as muscle weakness may reflect a global effect of aging, we further investigated whether tongue strength is correlated with handgrip strength. We assessed 78 healthy community-dwelling older adults (M = 77.3 years, SD = 7.26) for aspiration status (37% aspirators) via flexible endoscopic evaluation of swallowing. Maximal isometric anterior and posterior tongue strength, anterior and posterior swallowing tongue strength, and maximum handgrip strength were measured. Isometric tongue strength was significantly lower in aspirators versus nonaspirators (p = .03) at both the anterior (463 vs 548 mmHg, respectively) and posterior lingual locations (285 vs 370 mmHg, respectively). Likewise, swallowing tongue strength was significantly lower in aspirators versus nonaspirators at both the anterior (270 vs 317 mmHg, respectively) and posterior lingual locations (220 vs 267 mmHg, respectively). There was no difference between aspirators and nonaspirators' handgrip strength (p > .05), although handgrip strength was correlated with posterior tongue strength (r = .34, p = .005). Lower anterior and posterior isometric and swallowing tongue strength were dependent on aspiration status. Lower lingual strength in healthy adults may predispose them to aspiration. The correlation between tongue and handgrip strength is consistent with the hypothesis that impaired oropharyngeal strength reflects global age-related declines in muscle strength.

Grip strength is important for fine motor skills, and one of the measurement tools for grip strength is the Martin Vigorimeter (MV) dynamometer. Studies on establishing the reliability and validity of the MV in Koreans are limited. We aimed to establish the reliability and validity of the MV for grip strength measurement in healthy Korean adults by comparing it with the Jamar dynamometer, the standard tool used by the American Society of Hand Therapists. In total, 99 healthy participants (50 men and 49 women) were enrolled. Grip strength was measured using the Jamar dynamometer and MV. Reliability and validity were assessed using the intraclass correlation coefficient (ICC) and minimal detectable change (MDC). The correlation between the measurements of the instruments was analyzed using Pearson's correlation. The effect of hand anthropometry was evaluated, and the conversion equation between the instruments was calculated. MV showed excellent reliability (ICC > 0.90, p < 0.001) and validity with a high correlation (0.7 ≤ r < 0.9) with the Jamar dynamometer. The MDC was acceptable for detecting minimal clinically important differences (< 19.5%) in both instruments (Jamar: 3.4%-6.7%, MV: 3.8% to 6.3%). The grip strength measured using the MV was independent of hand anthropometry, unlike that using the Jamar dynamometer. This study provides insights into the relationship between the Jamar and MV instruments for measuring grip strength in Koreans. The MV is a viable alternative to the Jamar dynamometer in Koreans, offering not only reproducible and reliable measurements of grip strength but also the advantage of being unaffected by variations in hand anthropometry.

The purpose of this study was to investigate the reliability of tongue and handgrip strength and endurance measurements in healthy adults using the Iowa Oral Performance Instrument. Fifty-one healthy participants (21 males, 30 females; age range = 19-57 years) were tested on four occasions 1 week apart to determine test-retest reliability. The primary outcome measures were isometric tongue and handgrip strength (best of three trials) and sustained isometric endurance. Small increases (changes in group mean) in both anterior (1.7 %) and posterior (2.5 %) tongue strength and handgrip strength (5 %) between weeks 1 and 2 were observed with no change in subsequent weeks, suggesting that there is only a small learning effect for these measurements. The within-subject variation (mean-typical error expressed as a coefficient of variation [CV]) indicated higher than desirable initial variation for anterior (CV 10.8 %) and posterior (CV 11.8 %) tongue strength and handgrip strength (CV 15.2 %) but this was reduced in weeks 2-4. Intraclass correlation coefficients (ICC) indicated acceptable and improved reliability for both anterior (ICC 0.77-0.90) and posterior (ICC 0.79-0.86) tongue strength and handgrip strength (ICC 0.69-0.91) after week 1. Additional exploratory analyses were conducted with a subset of data to determine whether two values within 5 kPa (tongue) or 15 kPa (handgrip) provide superior strength reliability. Neither tongue nor hand endurance measurements were sufficiently reliable. These findings suggest that tongue and handgrip strength values demonstrate acceptable reliability, especially if familiarization is provided. Further investigation is needed to reduce sources of variability in tongue endurance measurements.

Objective There are limited reports about the reliability of measuring neck extensor muscle strength using a portable dynamometer in neck pain patients. The aims of the current study were 1) to investigate intra- and inter-rater reliability of neck extensor isometric strength measurement using a portable dynamometer in patients with chronic nonspecific neck pain (CNSNP) and 2) to compare neck extensor isometric strength in participants with and without CNSNP. Methods Guidelines for Reporting Reliability and Agreement Studies (GRRAS) were followed. Two examiners received a 15-minute training before enrollment. Inter-rater reliability was assessed with a 10-minute interval between measurements, and intra-rater reliability was assessed with a 10-day interval. Three trials were assessed and examiners were blind to the strength values (in Newtons) from other sessions of 20 individuals with CNSNP (mean±SD= 37.9 ± 9.8y; Neck Disability Index 29.2 ± 7.4%) and 20 individuals with other musculoskeletal disorders (mean ± SD = 32.8 ± 46.2y). Results Intra-rater reliability was excellent with intraclass correlation coefficient (ICC)(3,1) of 0.95 (CI:0.90–0.97) and inter-rater reliability was good to excellent with ICC(2,1) of 0.88 (CI:0.77–0.94) in CNSNP. No significant difference of neck extensor strength was found between CNSNP (93.27N±31.94) and Individuals without CNSNP (111.43N±40.11) (p > 0.05). Conclusion A portable dynamometer is a reliable tool for measuring maximal isometric neck extension strength in individuals with CNSNP. Slightly but no significant differences of neck extensor strength values between individuals with and without CNSNP. Future studies are needed to assess the generalizability of the findings in patients with other muscle deconditioning.

Purpose: The make and break tests are used in isometric muscle measurement via a handheld dynamometer. This study aimed to compare the reliability of intrinsic foot muscle strength assessment with break and make tests in healthy young adults. Methods: Seventy-five healthy adults completed the test-retest protocol with five days between tests. The maximal isometric strength measure of intrinsic foot muscles was measured during make/break tests using a handheld dynamometer. Test-retest reliability was calculated using intra-class correlation coefficients (ICC). Minimal detectable changes were calculated using standard error measurements. Results: According to the analysis, the strength results of the break test were higher in all muscles when compared to the make test (p&amp;lt;0.05). The strength measurements of the intrinsic foot muscles was found to have almost perfect test-retest reliability in the make and break test (ICC=0.938-0.986). Conclusion: Healthy adults showed stable test-retest results on all muscle strength measurements of the intrinsic foot muscles. The make and break test carried out usnig the handheld dynamometer is a reliable method for assessing intrinsic foot muscle strength in healthy adults. Both make and break tests are reliable measurements for the strength of intrinsic foot muscles.

BACKGROUND: A single measure to characterize overall muscle strength is advantageous because it saves time and costs of evaluation. For this reason, the back-leg-chest (BLC) strength might be an appropriate single measure in characterizing total body strength. OBJECTIVE: To assess the test-retest reproducibility and smallest real difference (SRD) of the BLC dynamometer in healthy adults and adolescents and to examine whether handgrip, knee-extensor and knee-flexor strength predict BLC strength in healthy adults. METHODS: Forty-five adults and 58 adolescents were recruited. In a first session back-leg-chest strength, handgrip strength, and additionally, in adults, isometric knee-extensor strength, and knee-flexor strength were measured. In a second session, 2-5 days later, BLC strength was measured again for test-retest reproducibility. RESULTS: Inter-session correlations of BLC strength were high (all r's and ICC's &gt; 0.92). Bland-Altman-plots showed high agreement. The SRD and SRD% were between 14-26, and 19% and 26% respectively. Strength variables (handgrip, knee-extensor, and knee-flexor strength) explained 87% of the variance in BLC strength. A stepwise linear regression showed that dominant knee extensor and flexor strength were the most important significant predictors of BLC strength (r2 = 0.86). CONCLUSIONS: This study demonstrated that the BLC dynamometer has reasonably high test-retest reproducibility and hence may serve in some pertinent situations to be an appropriate tool for clinical, basic and applied research.

Reliability of VALD DynaMo dynamometer to assess upper and lower body isometric strength in healthy adults.

BackgroundHigh prevalence rates have been reported for physical inactivity, mobility limitations, and falls in older adults. Home-based exercise might be an adequate means to increase physical activity by improving health- (i.e., muscle strength) and skill-related components of physical fitness (i.e., balance), particularly in times of restricted physical activity due to pandemics.ObjectiveThe objective of this study was to examine the effects of home-based balance exercises conducted during daily tooth brushing on measures of balance and muscle strength in healthy older adults.MethodsFifty-one older adults were randomly assigned to a balance exercise group (n = 27; age: 65.1 ± 1.1 years) or a passive control group (n = 24; age: 66.2 ± 3.3 years). The intervention group conducted balance exercises over a period of eight weeks twice daily for three minutes each during their daily tooth brushing routine. Pre- and post-intervention, tests were included for the assessment of static steady-state balance (i.e., Romberg test), dynamic steady-state balance (i.e., 10-m single and dual-task walk test using a cognitive and motor interference task), proactive balance (i.e., Timed-Up-and-Go Test [TUG], Functional-Reach-Test [FRT]), and muscle strength (i.e., Chair-Rise-Test [CRT]).ResultsIrrespective of group, the statistical analysis revealed significant main effects for time (pre vs. post) for dual-task gait speed (p < .001, 1.12 ≤ d ≤ 2.65), TUG (p < .001, d = 1.17), FRT (p = .002, d = 0.92), and CRT (p = .002, d = 0.94) but not for single-task gait speed and for the Romberg-Test. No significant group × time interactions were found for any of the investigated variables.ConclusionsThe applied lifestyle balance training program conducted twice daily during tooth brushing routines appears not to be sufficient in terms of exercise dosage and difficulty level to enhance balance and muscle strength in healthy adults aged 60–72 years. Consequently, structured balance training programs using higher exercise dosages and/or more difficult balance tasks are recommended for older adults to improve balance and muscle strength.

Grip strengthis not only very important in the daily life but also a major part in sports, including Judo, climbing, baseball and racquets sports. The strength of grip directlyinfluences the performance, so it is an important topic to improve grip strengtheffectively. Recently, Kinesio taping becomes very popular in athletes, it is believed that Kinesio taping can reduce pain, improve body fluid circulation and sport performance. However, the effects of Kinesio taping have not been confirmed in clinical studies. According to recent research, there are no significan differences between Kinesio taping and placebo taping in reducing pain and improving performance. Additionally, few studies have examined the effects of Kinesio taping on grip strength. PURPOSE: To examine the effects of Kinesio taping on maximal grip strength in healthy adults. METHODS: Twelve healthy adult subjects voluntarily participated in this study. Themaximal grip strength for both hands was measured via the JAMAR Hydraulic Hand Dynamometer. The average of the three trials of each hand was recorded for analysis. The forearm facilitation taping was applied one week after the first grip strength testing (without taping), and the grip strength testing was performed again. The maximal grip strength in the two conditions was compared using the Wilcoxon signed-rank test. RESULTS: Twelve healthy adult subjects completed this study. The maximal grip strength of right hand was less in the Kinesio taping condition as compared to no taping condition (35.97 ± 10.16 vs. 40.42 ± 10.96 kg, p =0.002). Left hand also showed less strength in the Kinesio taping condition as compared to no taping condition (32.89 ± 8.27 vs. 35.31 ± 9.47 kg, p=0.003). CONCLUSION: Kinesio taping appears to have no positive effect on facilitating maximal grip strength in healthy adults.

To determine intrasession and intersession reliability of strength measurements and hamstrings to quadriceps strength imbalance ratios (H/Q ratios) using the new isoforce dynamometer. Repeated measures. Exercise science laboratory. Thirty healthy subjects (15 females, 15 males, 27.8 years). Coefficient of variation (CV) and intraclass correlation coefficients (ICC) were calculated for (1) strength parameters, that is peak torque, mean work, and mean power for concentric and eccentric maximal voluntary contractions; isometric maximal voluntary torque (IMVT); rate of torque development (RTD), and (2) H/Q ratios, that is conventional concentric, eccentric, and isometric H/Q ratios (Hcon/Qcon at 60 deg/s, 120 deg/s, and 180 deg/s, Hecc/Qecc at -60 deg/s and Hiso/Qiso) and functional eccentric antagonist to concentric agonist H/Q ratios (Hecc/Qcon and Hcon/Qecc). High reliability: CV <10%, ICC >0.90; moderate reliability: CV between 10% and 20%, ICC between 0.80 and 0.90; low reliability: CV >20%, ICC <0.80. (1) Strength parameters: (a) high intrasession reliability for concentric, eccentric, and isometric measurements, (b) moderate-to-high intersession reliability for concentric and eccentric measurements and IMVT, and (c) moderate-to-high intrasession reliability but low intersession reliability for RTD. (2) H/Q ratios: (a) moderate-to-high intrasession reliability for conventional ratios, (b) high intrasession reliability for functional ratios, (c) higher intersession reliability for Hcon/Qcon and Hiso/Qiso (moderate to high) than Hecc/Qecc (low to moderate), and (d) higher intersession reliability for conventional H/Q ratios (low to high) than functional H/Q ratios (low to moderate). The results have confirmed the reliability of strength parameters and the most frequently used H/Q ratios.

Grip Strength in Older Adults: Test-Retest Reliability and Cutoff for Subjective Weakness of Using the Hands in Heavy Tasks

BackgroundMuscular strength is a key parameter of rehabilitation programs and a strong predictor of functional capacity. Traditional methods to measure strength, such as manual muscle testing (MMT) and hand-held dynamometry (HHD), are limited by the strength and experience of the tester. The Performance Recorder 1 (PR1) is a strength assessment tool attached to resistance training equipment and may be a time- and cost-effective tool to measure strength in clinical practice that overcomes some limitations of MMT and HHD. However, reliability and validity of the PR1 have not been reported. Methods: Test-retest and inter-rater reliability was assessed using the PR1 in healthy adults (n = 15) during isometric knee flexion and extension. Criterion-related validity was assessed through comparison of values obtained from the PR1 and Biodex® isokinetic dynamometer. Results: Test-retest reliability was excellent for peak knee flexion (intra-class correlation coefficient [ICC] of 0.96, 95% CI: 0.85, 0.99) and knee extension (ICC = 0.96, 95% CI: 0.87, 0.99). Inter-rater reliability was also excellent for peak knee flexion (ICC = 0.95, 95% CI: 0.85, 0.99) and peak knee extension (ICC = 0.97, 95% CI: 0.91, 0.99). Validity was moderate for peak knee flexion (ICC = 0.75, 95% CI: 0.38, 0.92) but poor for peak knee extension (ICC = 0.37, 95% CI: 0, 0.73). Conclusions: The PR1 provides a reliable measure of isometric knee flexor and extensor strength in healthy adults that could be used in the clinical setting, but absolute values may not be comparable to strength assessment by gold-standard measures.

Individual finger strength:: Are the ulnar digits “powerful”?

Measuring intrinsic hand strength in healthy adults: The accuracy intrarater and inter-rater reliability of the Rotterdam Intrinsic Hand Myometer