©Journal of Sports Science and Medicine (2025) 24, 543-554

http://www.jssm.org DOI: https://doi.org/10.52082/jssm.2025.543

` Review article

Impact of Potential Moderating Factors on Absolute Test-Retest Reliability of

Grip Strength Measurements in Healthy Populations: A Systematic Review with
Meta-Analysis

Takashi Abe 1,2, Jun Seob Song 3, Scott J. Dankel 4, Ricardo B. Viana 5, Akemi Abe 2 and Jeremy P.
Loenneke 6
1
Graduate School of Health and Sports Science, Institute of Health and Sports Science & Medicine, Juntendo University,
Chiba, Japan; 2 Division of Children’s Health and Exercise Research, Institute of Trainology, Fukuoka, Japan; 3 Depart-
ment of Counseling, Health and Kinesiology, Texas A&M University-San Antonio, San Antonio, TX, USA; 4 Department
of Health and Exercise Science, Rowan University, Glassboro, NJ, USA; 5 Human Anatomy Laboratory, Institute of
Physical Education and Sport, Federal University of Ceará, Fortaleza, Ceará, Brazil; 6 Department of Health, Exercise
Science, and Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi,
Oxford, MS, USA

2022; Bohannon, 2015; Bohannon, 2019; Norman et al.,

Abstract 2011). An online literature search (i.e., grip strength as a
Grip strength, a biomarker, can be measured at any age; however, keyword) using PubMed identified over 48,000 publica-
its values vary daily for each individual, which impacts the as- tions at a rate of over 3,500 per year in the last five years.
sessment. Absolute test-retest reliability (i.e., minimal difference, These publications include scientific literature and guide-
MD) is commonly defined as the variation in absolute values of lines discussing grip strength's reference values in each age
measurements taken by a single person or instrument on the same
item under identical conditions. Nevertheless, the potential mod-
group in both sexes (Abe et al., 2016; Hanten et al., 1999;
erators of absolute repeatability in grip strength measurements Ramirez-Velez et al., 2021) and its association with current
have not yet been fully elucidated. We conducted a systematic and future health (Celis-Morales et al., 2017; Peralta et al.,
review with meta-analysis to examine the influence of potential 2023; Rantanen et al., 2003). For example, grip strength
moderating factors on the absolute test-retest repeatability of grip increases dramatically from preschool children to young
strength measurements in healthy populations. PubMed, Scopus, adults, maintains stability in middle age, and then declines
and SPORTDiscus databases were searched up to January 2025 in old age (Abe et al., 2024; Loenneke et al., 2024;
following the PRISMA guidelines, and 48 studies were included Stenholm et al., 2012). In children and adolescents, grip
in this review. Age, test-retest interval, and device were used as strength may be a valuable indicator of bone health that
potential moderating factors; however, sex and sports experience
were excluded due to the limited number of published articles.
improves with growth (Saint-Maurice et al., 2018). Grip
We found considerable variation among studies reporting MD strength is also used as a criterion for diagnosing sarcope-
and percentage of MD to measured value (%MD) across each age nia in middle-aged and older men and women (Cruz-Jen-
group. The mean MD (%MD) values were 1.9 kg (25.4%) in toft et al., 2019). However, individual grip strength varies
young children (<7 years old), 2.5 kg (13.8%) in children (7-10 daily, and the degree of these changes may differ depend-
years old), 4.2 kg (17.1%) in adolescents (10 - 18 years old), 4.0 ing on age, sex, device type, and sports experience (i.e.,
kg (11.6%) in young adults (18 - 35 years old), and 4.7 kg (16.7%) athletes). For example, assuming similar daily variation in
in older adults (>60 years old). Neither age [effect size [ES]: each individual, the absolute test-retest reliability of grip
0.015 (95% confidence interval [CI]: -0.004, 0.035; p = 0.113) for strength measurements is expected to differ, being lower in
MD and ES: -0.025 (95% CI: -0.089, 0.039; p = 0.439) for %MD],
test-retest interval [ES: 0.006 (95% CI: -0.002, 0.013; p = 0.143)
children and older adults with low grip strength levels than
for MD and ES: 0.022 (95% CI: -0.001, 0.046; p = 0.065) for in younger adults. The same is true for both men and
%MD] nor handgrip device (p = 0.752 for MD and p = 0.334 for women in adolescence and beyond. Additionally, athletes
%MD) served as significant moderators of MD and %MD relia- in sports may be better equipped to consistently exert max-
bility. Due to the limited number of studies, sex and sports expe- imum muscle strength. Thus, measurement error should be
rience were excluded from the analysis; as a result, their impacts considered when comparing the measured grip strength
remain unknown. values with the evaluation or diagnosis criteria.
As is the case with many studies assessing reliabil-
Key words: Dynamometer, handgrip, reproducibility, peak mus-
cular strength.
ity in the exercise science literature, the intraclass correla-
tion coefficient (ICC) appears to be the preferred method
for reporting the reliability of grip strength measurements
Introduction (Bobos et al., 2020; Bohannon, 2017). One major limita-
tion with reporting ICC values is that they are entirely de-
Grip (or handgrip) strength is an extensively used bi- pendent on the heterogeneity of the sample included in the
omarker in research and clinical practice within the health, reliability assessment (i.e. between subject variability)
sports science, nutrition, and medical fields (Abe et al., given that the ICC is calculated with the following formula:

Received: 18 April 2025 / Accepted: 25 June 2025 / Published (online): 01 September 2025
544 Absolute grip strength test-retest reliability

on absolute test-retest repeatability of grip strength meas-

urements in healthy populations.
Thus, if the sample recruited is very homogenous
(low between subject variability), the ICC values will Methods
likely be small demonstrating poor reliability, even if the
absolute test-retest reliability is good. On the contrary, if We conducted this systematic review according to the Pre-
the sample recruited is very heterogenous (high between ferred Reporting Items for Systematic Review and Meta-
subject variability), the ICC values will likely be high Analysis (PRISMA) statement (Page et al., 2021). The
demonstrating good reliability, even if the absolute test-re- study was pre-registered (January 8, 2025) in the Interna-
test reliability is not good (Weir, 2005). While there are tional Prospective Register of Systematic Reviews
certainly instances where relative reliability may be im- (PROSPERO) (CRD42025635760).
portant (i.e. epidemiologic studies, correlations between English-language searches of the electronic data-
variables, etc.), often absolute reliability (i.e., standard er- bases PubMed, Scopus, and SPORTDiscus were con-
ror of measurement (SEM) and minimal difference (MD)) ducted from inception to January 9, 2025, by a researcher
is preferred and more useful (Weir, 2005). For example, (J.S.S.). Relevant articles were retrieved from electronic
whenever repeated measures are used (i.e. training inter- databases combining the following terms: (handgrip OR
ventions), individuals are only compared to themselves, so grip) AND (reliability OR retest OR reproducibility OR re-
factoring in between subject variability is not important. peatability). Initially, all files were extracted from data-
However, good absolute test-retest reliability will reduce bases in either RIS (Scopus and SPORTDiscus) or NBIB
the variability (i.e. error) amongst repeated measures, im- (PubMed) format. The files were then uploaded into Ray-
proving the ability to detect true changes by reducing the yan software, where duplicates were eliminated. Subse-
denominator in the test statistic. The same holds true for quently, two reviewers (T.A. and J.S.S.) independently
detecting differences between groups, where better abso- checked the titles and abstracts of identified articles for rel-
lute test-retest reliability within each group is preferred to evance. The reviewers then independently reviewed the
lower the pooled standard error. Despite the importance of full text of potentially eligible papers. Any disagreements
establishing absolute test-retest reliability of grip strength, between the reviewers on inclusion were resolved by a con-
it is unclear to what extent it varies with age and other sensus between both reviewers. Additional articles were
physical factors and measurement methods (e.g., time in- identified via hand-searching and reviewing the reference
terval, device used). Therefore, this systematic review with list of relevant papers. The study selection process is sum-
meta-analysis examined the impact of potential moderators marized using the PRISMA flow diagram (Figure 1).

Records identified through

database searching: (n = 4233)
I dentification

Records removed before screening:

 PubMed = 1360
 SPORTDiscus = 331 Duplicate records removed (n = 1508)
 Scopus = 2542

Records screened:
Records excluded: (n = 2162)
(n = 2725)

Reports sought for retrieval:

Reports not retrieved: (n = 0)
(n = 563)
Screening

Reports assessed for eligibility: Reports excluded: (n = 518)

(n = 563) Reasons:
 Foreign language (n = 1)
 Wrong population (n = 107)
 Wrong outcome (n = 282)
 No reliability study (n = 117)
 No original study (n = 3)
 No standardized handgrip device (n = 8)
I ncluded

Studies included in review: Additional studies included through

(n = 48) reference list and author research: (n = 3)

Figure 1. PRISMA flowchart of outcomes of the search strategy.

Abe et al. 545

To be included in this systematic review, studies two researchers (S.J.D. and J.S.S.) independently evalu-
were required to fulfill the following criteria: (1) a pub- ated the included studies. Seven relevant items were ex-
lished original study written in English language; (2) tracted from the modified checklist: 1) Subject characteris-
healthy participants with no restrictions on age, sex, and tics were clearly described, 2) The competence of the raters
physical activity/training status; (3) measured maximum was explicitly detailed, 3) Raters were blinded to their pre-
handgrip strength using a standardized handgrip dyna- vious findings, 4) The time interval between repeated
mometer at both test and retest, with the same investigator measures was appropriate, 5) The execution of the test was
conducting the measurements (i.e., intra-observer); and (4) described in sufficient detail to allow replication, 6) Study
reported absolute reliability (i.e., MD) or provided data participant's withdrawals were clearly explained, 7) The
needed to calculate absolute reliability (e.g., standard error statistical methods were suitable for the study's objectives.
of measurement, standard deviation of test-retest mean dif- Other items were not included as they were not considered
ference). Studies were included if they targeted healthy relevant for this review. The score for each item was deter-
participants based on the title and abstract of the articles, mined as follows: 1 = yes; 0 = no. Consequently, the max-
but were excluded if they targeted participants with any imal possible score was 7.
diseases. When reliability information was not available in To account for the dependency of multiple effect
the title and abstract, we examined the characteristics of the sizes nested within individual studies, a multi-level model
participants in the articles. If there was no mention of a was employed using the metafor package (version 4.6 - 0)
study participant's chronic diseases, they were considered in RStudio (version: 2024.12.1 + 563) (Assink and
"healthy individuals." If a study did not report absolute re- Wibbelink, 2016). Three models were computed to assess
liability, then we calculated the MD using: the standard de- 1) the MD, 2) the %MD, and 3) systematic bias (test 2 -
viation of test-retest mean difference (SDd) (Equation 1); test 1). Since the effect sizes of interest were computed off
and SEM (Equation 2). variability statistics to assess reliability, each of the studies
was weighted based on the sample size as we have done
Equation 1: 𝑀𝐷 𝑆𝐷𝑑 1.96 previously (Dankel et al., 2019). Three moderating varia-
Equation 2: 𝑀𝐷 𝑆𝐸𝑀 1.96 √2 bles were also assessed for the MD and %MD which in-
If a study reported the test-retest pooled SD with in- cluded: 1) age (continuous: years), 2) time interval between
traclass correlation (ICC), we first calculated the SEM us- test-retest (continuous: days), and handgrip device used
ing Equation 3. The calculated SEM was then used to de- (categorical: Jamar, Takei, other) to determine their influ-
termine the MD using Equation 2. For studies that did not ence on reliability. For systematic bias (calculated as the
report the test-retest pooled SD, we used the SD of test change from test 1 to test 2), age was used as a moderator
(pre-test), assuming that test-retest pooled SD and test SD to determine if children or younger adults may have expe-
would be similar, as both tests were completed by the same rienced a greater learning effect. Sex and sports experience
individuals. were not used as moderating variables for any of the anal-
yses, given the limited number of studies that assessed
Equation 3: 𝑆𝐸𝑀 males and females separately and the limited number of
𝑡𝑒𝑠𝑡 & 𝑟𝑒𝑡𝑒𝑠𝑡 𝑝𝑜𝑜𝑙𝑒𝑑 𝑆𝐷 𝑜𝑟 𝑡𝑒𝑠𝑡 𝑆𝐷 √ 1 𝐼𝐶𝐶 studies assessing athletes. In summarizing the results (Ta-
bles 1, 2, and 3), the following age ranges were used for
The percentage MD (%MD) was calculated follow- age categorization: young children (under 7 years old),
ing Equation 4. When the study did not report test-retest children (between 7 - 10 years old), adolescents (between
pooled values, the mean grip strength was calculated as av- 10 - 18 years old), young adults (between 18 - 35 years
erage using the test and retest values. old), middle-aged adults (between 36 - 60 years old), and
Equation 4: %MD = MD ÷ mean test & retest grip older adults (>60 years old). Statistical significance was set
strength 100 at p < 0.05.

The following study characteristics were extracted: Results

authors, publication year, participants’ characteristics (age,
sex, and health status), sample size, handgrip device, time Included studies and participant and research protocol
interval between test and retest, handgrip strength at test characteristics
and retest (with SD), test and retest mean difference (with The original article search yielded 4,233 studies. Three ad-
SD), ICC, SEM, and MD. Two researchers (T.A. and ditional studies were identified from the reference lists of
J.S.S.) extracted these data manually, with disagreement the included articles. After removing duplicates and elimi-
resolved by consensus between both researchers. To stand- nating articles based on the eligibility criteria, 48 studies
ardize grip strength values to kilogram units, those reported (Abe et al., 2018; Abe et al., 2019; Abe et al., 2022;
in newtons were converted as follows: 1 N = 0.10197 kg. Amado-Pacheco et al., 2019; Anstey et al., 1997; Balogun
In studies reporting the sum of grip strength values for both et al., 1991; Beauchamp et al., 2021; Biasini et al., 2023;
the left and right hands, the MD value was divided by 2 for Bohannon, 2006; Bohannon and Schaubert, 2005; Bohan-
statistical processing, as many studies used grip strength non et al., 2011; Boshnjaku et al., 2021; Cadenas-Sanchez
values and MD values for one hand. et al., 2016; Cildan Uysal et al., 2022; Dugdale et al., 2019;
A modified version of the critical appraisal tool was Espana-Romero et al., 2010; Essendrop et al., 2001; Fer-
utilized to evaluate the methodological quality of the stud- nandez-Santos et al., 2016; Ferreira et al., 2021; Gasior et
ies included in this review (Brink and Louw, 2011), and al., 2020; Gerodimos, 2012; Gerodimos and Karatrantou,
546 Absolute grip strength test-retest reliability

Table 1. Study characteristics and absolute reliability in children and adolescents.

Author (Year) Age (yr) Sex Device Interval Arm HGS test1 HGS test2 MD (kg) % MD
Young Children (< 7 years old)
Svensson et al (2008) 6 years 19BG Grippit 7 days NR 7.65 (2.24) 7.85 (2.65) 1.36 17.5
Sanchez-Delgado (3-5) 32B 6.6 (3.0) 6.2 (2.6) 2.52 39.4
Takei 3 hours NR
et al (2015) (3-5) 24G 6.6 (3.1) 6.7 (3.0) 2.17 32.7
Cadenas-Sanchez 4.90 (0.86) 92B Avg of 8.40 (2.40) 8.02 (2.56) 2.59 31.5
Takei 14 days
et al (2016) 4.82 (0.79) 69G both hands 7.24 (2.34) 7.22 (2.21) 2.37 32.8
Amado-Pacheco 4.04 (0.82) 48B Avg of 8.19 (2.46) 8.10 (2.39) 1.14 14.0
NR 14 days
et al (2019) 3.95 (0.82) 42G both hands 7.30 (1.95) 7.35 (1.92) 1.41 19.3
Abe et al (2022) 6.1 (0.3) 8B 5G Takei 7 days Right 10.3 (1.4) 10.1 (1.1) 1.60 15.8
King-Dowling 22B Dominant 7.4 (1.6) 7.8 (1.6) 2.16 28.4
4.7 (0.6) Takei 2-3 weeks
et al (2024) 20G Nondominant 7.7 (1.5) 7.8 (1.5) 1.76 22.8
Children (7-10 years)
Espana-Romero Sum of
(6-11) 58BG Takei 7 days 29.9 (4.9) 28.4 (3.8) 4.31 14.8
et al (2010) both hands
30B Preferred 20.06 (4.67) 20.32 (4.81) 3.23 16.0
Gerodimos (2012) 9.85 (0.70) Jamar 24 hours
[BB] Non-preferred 19.78 (4.59) 19.92 (4.59) 2.37 12.0
Gerodimos & 27B Preferred 22.33 (3.37) 22.11 (3.66) 2.55 11.5
9.49 (0.96) Jamar 24 hours
Karatrantou (2013) [WR] Non-preferred 21.78 (3.30) 21.59 (3.42) 2.74 12.7
Fernandez-Santos Sum of
8.7 (1.8) 98B 82G Takei 7 days 31.5 (10.1) 31.3 (9.9) 5.25 16.7
et al (2016) both hands
Gasior et al (2020) 7~9 69B 68G Jamar 24 hours Dominant 13.25 (3.28) 13.75 (3.34) 1.78 13.2
Adolescents (10-18 years old)
Svensson 10 years 20BG 15.7 (3.98) 17.0 (4.89) 5.68 34.8
Grippit 7 days NR
et al (2008) 14 years 19BG 32.3 (8.66) 33.1 (8.57) 4.74 14.5
Ortega 13.7 (0.8) 69B Avg of 31.2 (6.4) 31.5 (6.9) 4.90 15.6
Takei 2 weeks
et al (2008) 13.6 (0.8) 54G both hands 26.1 (5.1) 26.1 (4.9) 3.53 13.5
Espana-Romero Sum of
(12-18) 80BG Takei 7 days 50.5 (14.6) 51.9 (15.3) 9.60 18.8
et al (2010) both hands
14.37 30B Preferred 42.10 (9.44) 42.67 (9.15) 3.14 7.4
Gerodimos (2012) Jamar 24 hours
(0.61) [BB] Non-preferred 41.27 (8.41) 41.81 (8.73) 3.25 7.8
Gerodimos & 14.60 27B Preferred 47.07 (8.32) 47.26 (8.56) 2.94 6.2
Jamar 24 hours
Karatrantou (2013) (0.50) [WR] Non-preferred 46.67 (9.2) 46.63 (9.23) 3.60 7.7
Ramirez-Velez 12.8 (2.4) 124B Avg of both 19.6 (8.9) 19.0 (8.5) 3.92 20.3
Takei 7 days
et al (2015) 12.8 (2.5) 105G hands 16.9 (5.1) 16.5 (5.4) 3.14 18.8
26B 17.8 (2.6) 17.7 (2.9) 1.91 10.7
NR for 51B 18.1 (3.6) 18.7 (3.3) 4.11 22.4
each group, 75B 21.5 (4.5) 22.1 (4.8) 4.83 22.2
Dugdale et al (2019) overall 59B Takei 7-14 days Dominant 25.3 (5.3) 25.9 (5.8) 4.87 19.0
13.5 (1.8) 81B 33.2 (7.5) 33.4 (7.2) 5.88 17.7
[SO] 46B 37.7 (7.2) 38.3 (6.3) 5.28 13.9
35B 37.5 (7.3) 37.8 (7.0) 7.01 18.6
Gasior et al (2020) 10~13 87B 82G Jamar 24 hours Dominant 22.68 (5.60) 22.70 (5.50) 2.41 10.6
13.44
19B, 26G 21.5 (4.1) 21.5 (4.5) 2.16 10.0
O'Keeffe (0.35) Avg of both
Takei 7 days
et al (2020) 13.42 hands
20B, 21G 25.3 (5.4) 25.0 (5.3) 1.76 7.0
(0.32)
Right 20.50 (4.89) 19.32 (4.91) 5.25 26.4
Jamar
Trajkovic Left 18.64 (4.07) 18.01 (4.39) 5.17 28.2
12.2 (0.4) 32B 24G 5 days
et al (2024) Right 20.81 (4.84) 20.16 (5.34) 5.53 27.0
Takei
Left 19.22 (4.26) 19.01 (4.94) 5.54 29.0
B, boys; G, girls; Avg, average; NR, not reported; MD, minimal difference; %MD, percentage of a minimal difference to the measured value; HGS,
handgrip strength (unit in kilograms); BB, basketball players; WR, wrestlers; SO, soccer players

2013; Gil et al., 2022; Hamilton et al., 1992; Jenkins and and Adams, 2007) were included in this review. Of those
Cramer, 2017; Karatrantou et al., 2020; Kieser et al., 2025; studies, 16 included 42 data points assigned to children and
King-Dowling et al., 2024; Legg et al., 2020; Lemmink et adolescents (852 boys, 294 girls, and 879 mixed) (Abe et
al., 2001; Leszczak et al., 2024; Maurya et al., 2023; al., 2022; Amado-Pacheco et al., 2019; Cadenas-Sanchez
O’Keeffe et al., 2020; Ortega et al., 2008; Petersen et al., et al., 2016; Dugdale et al., 2019; Espana-Romero et al.,
2015; Plant et al., 2016; Ramirez-Velez et al., 2015; 2010; Fernandez-Santos et al., 2016; Gasior et al., 2020;
Sanchez-Delgado et al., 2015; Savva et al, 2013; Suzuki et Gerodimos, 2012; Gerodimos and Karatrantou, 2013;
al., 2019; Svensson et al., 2008; Tan et al., 2001; Trajkovic King-Dowling et al., 2024; O’Keeffe et al., 2020; Ortega
et al., 2024; Tsang, 2005; Venegas-Carro et al., 2022; Vil- et al., 2008; Ramirez-Velez et al., 2015; Sanchez-Delgado
lafane et al., 2016; Walamies and Turjanmaa, 1993; Ward et al., 2015; Svensson et al., 2008; Trajkovic et al., 2024)
Abe et al. 547

(Table 1), 25 included 50 data points assigned to young and et al., 2022; Villafane et al., 2016; Ward and Adams, 2007)
middle-aged adults (98 men, 109 women, and 1,244 and Takei (Abe et al., 2018; Abe et al., 2019; Abe et al.,
mixed) (Abe et al., 2018; Abe et al. 2019; Balogun et al., 2022; Cadenas-Sanchez et al., 2016; Dugdale et al., 2019;
1991; Beauchamp et al., 2021; Biasini et al., 2023; Bohan- Fernandez-Santos et al., 2016; Gerodimos and
non, 2006; Bohannon et al., 2011; Boshnjaku et al., 2021; Karatrantou, 2013; King-Dowling et al., 2024; O’Keeffe et
Cildan Uysal et al., 2022; Essendrop et al., 2001; Gerodi- al., 2020; Ortega et al., 2008; Petersen et al., 2015;
mos, 2012; Gil et al., 2022; Hamilton et al., 1992; Ramirez-Velez et al., 2015; Sanchez-Delgado et al., 2015;
Karatrantou et al., 2020; Kieser et al., 2025; Leszczak et al., Suzuki et al., 2019; Tan et al., 2001; Trajkovic et al., 2024).
2024; Maurya et al., 2023; Petersen et al., 2015; Plant et al., Other studies used different types of dynamometers, such
2016; Savva et al., 2013; Tan et al., 2001; Tsang, 2005; as Grippit (Svensson et al., 2008), JTECH (Biasini et al.,
Venegas-Carro et al., 2022; Walamies and Turjanmaa, 2023; Plant et al., 2016), and MicroFET (O’Keeffe et al.,
1993; Ward and Adams, 2007) (Table 3), and 12 included 2020). Two studies did not report the type of dynamome-
23 data points assigned to older adults (166 men, 292 ters (Amado-Pacheco et al., 2019; Beauchamp et al., 2021).
women, and 1,046 mixed) (Abe et al., 2018; Anstey et al., The most commonly used test-retest intervals were
1997; Beauchamp et al., 2021; Bohannon and Schaubert, 24 hours (Abe et al., 2018; Abe et al., 2019; Bohannon,
2005; Boshnjaku et al., 2021; Ferreira et al., 2021; Gil et 2006; Gasior et al., 2020; Gerodimos, 2012; Gerodimos et
al., 2022; Jenkins and Cramer, 2017; Legg et al., 2020; al., 2013; Tan et al., 2001; Ward and Adams, 2007) or 7
Lemmink et al., 2001; Suzuki et al., 2019; Villafane et al., days (Abe et al., 2022; Beauchamp et al., 2021; Espana-
2016) (Table 2). The following studies (Bohannon, 2006; Romero et al., 2010; Essendrop et al., 20 01; Fernandez-
Bohannon et al., 2011; Kieser et al., 2025; Plant et al., Santos et al., 2016; Ferreira et al., 2021; Gil et al., 2022;
2016; Tsang, 2005) included participants spanning a broad Hamilton et al., 1992; Lemmink et al., 2001; O’Keeffe et
range of adults (young, middle-aged, and older) and were al., 2020; Petersen et al., 2015; Ramirez-Velez et al., 2015;
therefore included in Table 3. Savva et al., 2013; Svensson et al., 2008; Venegas-Carro et
The main dynamometers used to measure grip al., 2022; Villafane et al., 2016), with several studies using
strength were Jamar (Abe et al., 2019; Bohannon and 2 weeks (Amado-Pacheco et al., 2019; Cadenas-Sanchez et
Schaubert, 2005; Bohannon et al., 2011; Boshnjaku et al., al., 2016; Hamilton et al., 1992; Leszczak et al., 2024; Or-
2021; Essendrop et al., 2001; Gasior et al., 2020; Gerodi- tega et al., 2008). In 41 of the 48 studies, the test-retest in-
mos, 2012; Gerodimos and Karatrantou,2013; Hamilton et terval was 2 weeks or less. Nine studies had a range of test-
al., 1992; Jenkins and Cramer, 2017; Karatrantou et al., retest intervals that were not consistent, such as within 7
2020; Legg et al., 2020; Lemmink et al., 2001; Savva et al., days (Balogun et al., 1991; Biasini et al., 2023; Maurya et
2013; Trajkovic et al., 2024; Tsang, 2005; Venegas-Carro al., 2023) or 2 - 10 days (Kieser et al., 2025).
Table 2. Study characteristics and absolute reliability in older adults (>60 years old).
Author (Year) Age (yr) Sex Device Interval Arm HGS test1 HGS test2 MD (kg) % MD
Anstey et al. Spedly Right 25.52 (4.55) 26.15 (5.91) 5.50 21.3
67.92 (4.89) 50W 3 months
(1997) manual Left 22.63 (4.16) 23.48 (5.03) 4.61 20.0
Lemmink et 65.8 (7.03) 68M 43.9 (8.00) 44.7 (8.45) 7.53 17.0
Jamar 7 days Preferred
al. (2001) 66.1 (6.75) 83W 28.1 (5.30) 29.3 (5.55) 6.17 21.5
Bohannon & Right 26.70 (7.39) 25.83 (7.05) 5.94 22.6
Schaubert 75.0 (5.9) 4M 17W Jamar 12 weeks
Left 24.71 (7.69) 24.36 (7.44) 4.51 18.4
(2005)
Villafane et Dominant 25.8 (9.9) 25.8 (9.9) 0.67 2.6
67.5 (10.2) 6M 9W Jamar 7 days
al. (2016) Nondominant 24.4 (10.5) 24.3 (10.6) 2.22 9.1
12 weeks 29.76 (9.27) 29.62 (8.83) 5.49 18.5
Jenkins & 76.8 (6.3) 98M
24 weeks 30.42 (9.09) 30.61 (8.98) 5.07 16.6
Cramer Jamar NR
12 weeks 17.60 (6.10) 17.63 (6.08) 3.38 19.2
(2017) 75.9 (6.6) 159W
24 weeks 18.17 (5.82) 18.27 (5.72) 2.66 14.6
Abe et al.
72 (3.8) 34M 46W Takei 1 year Right 31.8 (7.9) 29.5 (6.8) 6.4 21.1
(2018)
Suzuki et al.
≥65 197M 21W Takei NA Dominant 26.3 (6.8) 26.0 (6.8) 3.94 15.1
(2019)
Legg et al. Dominant 34.7 (15.1) 35.1 (14.4) 5.92 17.0
71 (10) 6M 11W Jamar 48 hours
(2020) Nondominant 32.6 (16.6) 33.6 (16.3) 4.60 13.9
Beauchamp 69 (3) 29M 521W 37.08 (12.79) 39.08 (13.23) 10.64 28.0
NR 7 days Dominant
et al. (2021) 81 (4) 29M 20W 29.41 (9.28) 36.65 (12.63) 5.16 15.6
Boshnjaku et
70.7 (6.1) 22M 39W Jamar 7-97 days Dominant 29.2 (9.2) 28.8 (9.3) 5.29 18.3
al. (2021)
Ferreira et al. Baseline Dominant 18.9 (5.9) 18.9 (5.8) 3.49 18.5
84.5 (6.5) 15M 28W 7 days
(2021) Smedley Non-dominant 17.1 (5.6) 17.4 (5.4) 2.91 16.9
Gil et al. Right 29.5 (8.4) 29.2 (8.0) 2.27 7.7
70.5 (5.0) 6M 6W Straingauge 7 days
(2022) Left 26.9 (7.8) 28.5 (7.1) 2.92 10.5
M, men; W, women; Avg, average; NR, not reported; MD, minimal difference; %MD, percentage of a minimal difference to the measured value; HGS,
handgrip strength (unit in kilograms)
 548 Absolute grip strength test-retest reliability

Table 3. Study characteristics and absolute reliability in young and middle-aged adults.
Author (Year) Age (yr) Sex Device Interval Arm HGS test1 HGS test2 MD (kg) % MD
Young Adults (18-35 years old)
Right 36.7 (7.7) 36.2 (7.3) 4.23 11.6
60M
within Left 35.4 (6.7) 35.0 (6.8) 4.59 13.0
Balogun et al. (1991) 23.7 (2.4) Harpenden
7 days Right 24.1 (5.2) 24.6 (5.0) 3.76 15.4
60W
Left 22.1 (4.5) 22.1 (4.2) 3.46 15.7
7 days 63.09 (9.43)* 69.21 (8.08)* 9.19 13.9
Hamilton et al. (1992) 23.8 (4.9) 29W Jamar Right
14 days 63.09 (9.43)* 66.23 (10.50)* 11.55 17.9
26.06 Preferred 66.49 (9.33) 66.71 (9.68) 4.57 6.9
Gerodimos (2012) 30M [BB] Jamar 24 hours
(5.57) Non-preferred 65.68 (9.16) 65.95 (9.26) 4.06 6.2
Savva et al. (2013) 21~26 10M 9W Jamar 7 days Dominant 35.6 (12.1) 36.2 (12.7) 6.45 18.0
Right 50.8 (10.6) (pooled) 5.43 10.7
Petersen et al. (2015) 25 (2) 8M Takei 7 days
Left 48.0 (10.7) (pooled) 6.93 14.4
Karatrantou et al. Preferred 40.45 (8.70) 40.65 (8.80) 2.66 6.6
18.5 (3.4) 14M 6W Jamar 3 days
(2020) Non-preferred 39.85 (9.42) 40.00 (8.81) 4.80 12.0
Boshnjaku et al. 7-97
22.6 (3.7) 31M 26W Jamar Dominant 41.5 (10.7) 42.3 (11.0) 5.29 12.6
(2021) days
Venegas-Carro et al. 7 days 47.7 (12) 47.9 (12) 3.1 6.6
24.2 (2.2) 10M 7W Jamar Preferred
(2022) 9 weeks 47.7 (12) 48.4 (14) 5.7 11.8
Right 35.0 (9.8) 35.8 (10.1) 4.78 13.5
Gil et al. (2022) 22.7 (2.8) 6M 6W Straingauge 7 days
Left 33.0 (8.9) 34.0 (9.0) 3.51 10.5
Right (standing) 25.92 (8.49) 25.86 (8.38) 2.68 10.4
Cildan Uysal et al. 22.32 K-Force Left (standing) 23.98 (8.01) 23.75 (7.3) 3.22 13.5
19M 31W 48 hours
(2022) (0.79) Grip Right (sitting) 25.67 (8.36) 25.58 (8.25) 2.84 11.1
Left (sitting) 23.69 (7.43) 23.64 (7.45) 3.32 14.0
Biasini et al. (2023) 24.4 (1.4) 10M 10W JTECH 2-5 days Dominant 45.4 (13.7) 44.4 (13.7) 6.90 15.4
Dynamo Torque 2-7
Maurya et al. (2023) 21 (3) 20W Dominant 18.8 (4.5) 18.2 (4.6) 3.37 18.2
Analyzer days
Right (rater #1) 35.36 (11.69) 35.44 (11.77) 2.16 6.1
22.2 Biometrics Left (rater #1) 30.47 (9.89) 30.50 (9.81) 1.65 5.4
Leszczak et al. (2024) 44M 78W 2 weeks
(1.46) E-Link EP9 Right (rater #2) 35.58 (11.66) 35.72 (11.70) 2.08 5.8
Left (rater #2) 30.06 (9.87) 30.01 (9.68) 1.98 6.6
Young and Middle-aged Adults
Walamies & 1-2
23-49 13M 27W Straingauge Dominant 36.9 (11.2) 37.5 (11.2) 4.39 11.8
Turjanmaa (1993) months
Essendrop et al. (2001) 35 (6.9) 6M 13W Jamar 7 days Right 39.8 (10.2) 41.5 (10.5) 4.00 9.8
12M, 9W
Tan et al. (2001) 34.3 (8.2) Takei 24 hours Bowling hand 38.2 (8.8) 37.4 (7.9) 6.45 17.1
[BL]
Dominant 32.77 (10.43) 32.2 (9.85) 6.70 20.6
Jamar
Non-dominant 30.79 (9.69) 29.94 (8.47) 6.53 21.5
Dominant 30.02 (8.17) 28.47 (8.91) 6.88 23.5
Ward & Adams (2007) 19~47 9M 21W MIE 24 hours
Non-dominant 27.56 (8.13) 27.55 (8.23) 5.76 20.9
Dominant 29.41 (12.04) 28.11 (12.38) 9.37 32.6
Lafayette
Non-dominant 27.84 (10.97) 26.11 (10.69) 7.61 28.2
Abe et al. (2018) 54 (6) 9M 9W Takei 24 hours Right 40.1 (10.9) 38.7 (11.4) 3.97 10.1
46.4 Takei 39.5 (10.8) 38.5 (10.8) 3.5 8.9
Abe et al. (2019) 10M 10W 24 hours Right
(13.2) Jamar 42.6 (12.8) 41.5 (12.8) 4.6 10.9
Beauchamp et al.
58 (4) 18M 30W NR 7 days Dominant 36.65 (12.63) 37.56 (12.84) 6.07 16.4
(2021)
Young, Middle-age and Older Adults
37.8 226M Dominant 36.2 (10.4) 35.7 (10.3) 6.10 17.0
Tsang et al. (2005) Jamar 3 days
(10.9) 322W Nondominant 33.7 (10.0) 33.3 (10.0) 6.10 18.2
38.0 Right 44.1 (15.3) 44.3 (16.1) 5.85 13.2
Bohannon (2006) 14M, 16W MicroFET 24 hours
(15.6) Left 42.2 (14.1) 41.8 (14.7) 4.79 11.4
45.7 4-10 Right 38.2 (10.0) 38.8 (10.8) 6.94 15.3
Bohannon et al. (2011) 14M, 14W Jamar
(23.5) days Left 35.9 (9.8) 36.5 (10.2) 5.88 19.2
JTECH
11.3 27.5 (9.6) 26.7 (8.9) 5.32 19.6
(Manual)
Plant et al. (2016) (23-67) 10M 15W (10.6) NR
JTECH
weeks 28.4 (10.2) 27.9 (9.4) 5.66 20.1
(Electronic)
48.0 2-10 Max value of
Kieser et al. (2025) 39M 61W Biopac 26.9 (9.7) 27.1 (9.6) 4.63 17.1
(20.2) days both hands
B, boys; G, girls; M, men; W, women; Avg, average; NR, not reported; MD, minimal difference; %MD, percentage of a minimal difference to the measured
value; HGS, handgrip strength (unit in kilograms); BB, basketball players; BL, 10-pin bowlers.
*The unit of measured grip strength was pounds per square inch. Thus, this study was not included in the minimal differences (MD) analysis.
Abe et al. 549

Table 4. Absolute reliability (minimal difference and percentage of minimal difference to the measured value) of grip
strength measurements according to age, sex, and hand dominance.
# of Studies Minimal Difference % Minimal Difference
Mean [Min, Max] Mean [Min, Max]
Young Children 6 1.9 [1.14, 2.59] 25.4 [14.0, 39.4]
Children 5 2.5 [1.78, 3.23] 13.8 [11.5, 16.7]
Adolescents 10 4.2 [1.76, 7.01] 17.1 [6.2, 34.8]
Age Group
Young Adults 13 4.0 [1.65, 6.93] 11.6 [5.4, 18.2]
Young & Middle-aged Adults 7 5.8 [3.97, 9.37] 17.9 [8.9, 32.6]
Older Adults 12 4.7 [0.67, 10.64] 16.7 [2.6, 28.0]
Boys 5 3.0 [1.14, 4.90] 24.2 [14.0, 39.4]
Girls 5 2.5 [1.41, 3.53] 23.4 [13.5, 32.8]
Sex
Men 3 5.4 [4.23, 7.53] 15.3 [11.6, 18.5]
Women 3 3.9 [2.66, 6.17] 17.3 [14.6, 21.5]
Dominant 11 3.4 [0.67, 6.1] 12.5 [6.6, 28.4]
Non-dominant 11 3.5 [1.76, 6.1] 12.7 [6.2, 22.8]
Hand
Right 11 4.4 [2.08, 6.97] 14.5 [5.8, 27.0]
Left 11 4.1 [1.65, 6.93] 15.3 [5.4, 29.0]
Min, minimum; Max, maximum
and %MD) in each age group (Figure 2 and 4). Specifically,
Assessment of methodological quality the mean MD value for young children (under 7 years old)
The mean score was 4.2 out of 7 (range: 2 - 7), indicating was 1.9 kg (Abe et al., 2022; Amado-Pacheco et al., 2019;
a methodological quality rating that varied from low to Cadenas-Sanchez et al., 2016; King-Dowling et al., 2024;
high (Supplementary Table 1). Seventeen of the 48 studies Sanchez-Delgado et al., 2015; Svensson et al., 2008), while
scored 5 or higher, while 10 received scores of 2 or 3. it was 2.5 kg for children aged 7 to 10 (Espana-Romero et
al., 2010; Fernandez-Santos et al., 2016; Gerodimos, 2012;
Gerodimos and Karatrantou, 2013; Gasior et al., 2020).
The mean MD for adolescents (10 - 18 years old) was 4.2
kg (Dugdale et al., 2019; Espana-Romero et al., 2010;
Gasior et al., 2020; Gerodimos, 2012; Gerodimos and
Karatrantou, 2013; O’Keeffe et al., 2020; Ortega et al.,
2008; Ramirez-Velez et al., 2015; Svensson et al., 2008;
Trajkovic et al., 2024), which is similar to young adults (18
- 35 years old; 4.0 kg) (Balogun et al., 1991; Biasini et al.,
2023; Boshnjaku et al., 2021; Cildan Uysal et al., 2022;
Gerodimos, 2012; Gil et al., 2022; Hamilton et al., 1992;
Karatrantou et al., 2020; Leszczak et al., 2024; Maurya et
al., 2023; Petersen et al., 2015; Savva et al., 2013; Vene-
gas-Carro et al., 2022). Middle-aged (36 - 60 years old) and
older (>60 years old) adults had an MD of approximately
5 - 6 kg. On the other hand, the mean %MD values in young
children and adolescents were approximately 25% and
17%, respectively, while those in young and older adults
were about 12% and 17%, respectively (Table 4).

Mean weighted reliability statistics

The overall weighted MD was 4.463 (95% confidence in-
Figure 2. The relationship between the average age of study terval [CI]: 3.926, 4.999; p < 0.001). As there was signifi-
participants and the absolute reliability [minimal difference cant heterogeneity (Q = 36,484.970 p < 0.001) that could
(MD) and percentage of minimal difference to the measured be attributed to both within (33.9%) and between (65.7%)
value (%MD)] of handgrip strength measurements. In studies
where MD was calculated using handgrip strength values of
study variance, potential moderators were examined. Nei-
both hands, 1/2 MD value was used. %MD = MD / average ther age [effect size [ES]: 0.015 (95% CI: -0.004, 0.035; p
handgrip strength * 100 = 0.113)], test-retest interval [ES: 0.006 (95% CI: -0.002,
0.013; p = 0.143)] nor handgrip device (p = 0.752) were
Impact of potential moderators on absolute test-retest significant moderators of reliability. The overall weighted
reliability of grip strength measurements %MD was 16.307 (95% CI: 14.529, 18.085; p < 0.001).
Nine of the 48 studies did not report the mean age of par- Like that of the absolute MD, neither age [ES: -0.025 (95%
ticipants, only an age range (Dugdale et al., 2019; Espana- CI: -0.089, 0.039; p = 0.439)], test-retest interval [ES:
Romero et al., 2010; Gasior et al., 2020; Plant et al., 2016; 0.022 (95% CI: -0.001, 0.046; p = 0.065)], or handgrip de-
Sanchez-Delgado et al., 2015; Suzuki et al., 2019; Svens- vice (p = 0.334) were significant moderators of reliability.
son et al., 2008; Walamies and Turjanmaa, 1993; Ward and There was also no apparent systematic bias [ES: 0.162
Adams, 2007). There was considerable variation among (95% CI: -0.139, 0.464; p = 0.291)], and the presence of
studies reporting absolute test-retest reliability (MD systematic bias was not moderated by age [ES: 0.005 (95%
550 Absolute grip strength test-retest reliability

CI: -0.006, 0.017; p = 0.380)] suggesting there was no and %MD calculated from the SEM of the test-retest relia-
learning effect, and this did not differ based on age. bility reported by the authors were 15.2 Nm and 30.9% for
Four studies reported absolute reliability for both knee extension and 9.7 Nm and 36.1% for knee flexion,
boys and girls (Amado-Pacheco et al., 2019; Cadenas- respectively. Another study (Santos et al., 2013) also as-
Sanchez et al., 2016; Ortega et al., 2008; Ramirez-Velez et sessed the test-retest reliability (7 days apart) of knee ex-
al., 2015; Sanchez-Delgado et al., 2015), while three stud- tension and flexion peak torque (60 degrees per second) in
ies focused on adult men and women (Bohannon, 2006; children with a mean age of 8.5 years. The %MD calcu-
Karatrantou et al., 2020; Maurya et al., 2023). The mean lated from SEM was 29.3% for the dominant leg, 33.1%
MD value was 3.0 kg for boys and 2.5 kg for girls, for the non-dominant leg for knee extension, and 46.2%
with %MD values of 24.2% and 23.4%, respectively. In and 32.6%, respectively, for knee flexion. The %MD val-
adults, the mean MD values were 3.9 kg for women and ues in these studies were similar to those observed in young
5.4 kg for men, with %MD values of 17.3% for women and children (< 7 years old) for grip strength measurements.
15.3% for men (Table 4). Considering that the mean %MD of grip strength measure-
No studies have compared the absolute reliability of ments in children of the same age group (7 - 10 years old)
grip strength measurements between participants with and was 13.8%, the %MD of the isokinetic strength measure
without sports experience. However, studies have been may appear high. In addition, a study (Maffiuletti et al.,
done on pre-pubertal, pubertal, and young adult basketball 2007) investigating the reproducibility (7 days apart) of
players (Gerodimos, 2012), pre-pubertal and pubertal knee extension and flexion peak torques under the same
wrestlers (Gerodimos and Karatrantou, 2013), youth soc- conditions (60 degrees per second) in young adults found
cer players (Dugdale et al., 2019), and middle-aged ten-pin that the %MD values are in the same range (10.7% for knee
bowlers (Tan et al., 2001). Moreover, twenty-two studies extension and 8.6% for knee flexion) as those observed in
measured grip strength in both the left and right hands; half grip strength measurements in young adults (11.6%).
(11 studies) compared dominant and non-dominant hands, Eighty-five percent (41 studies) of the 48 included
and the remaining 11 studies were able to compare right studies had a test-retest interval of less than two weeks,
and left hands (Table 4). with 7 days being the most common (16 studies). This may
explain why the test-retest interval did not affect grip
Discussion strength measurements' MD and %MD. Those results sug-
gest that at least a test-retest interval of two weeks or less
The current manuscript investigated the impact of potential may not significantly affect the grip strength reliability of
moderating factors on the absolute test-retest reliability of MD and %MD. Three included studies reported test-retest
grip strength measurements in a healthy population. This reliability at two different intervals: 7 days vs. 9 weeks
systematic review with meta-analysis included 48 studies (Venegas-Carro et al., 2022), 24 hours vs. 1 year (Abe et
involving 4,980 healthy participants (i.e., 2,025 children al., 2018), and 12 weeks vs. 24 weeks (Jenkins and Cramer,
and adolescents, 1,451 young and middle-aged adults, and 2017). For instance, Venegas-Carro et al. (2022) reported
1,504 older adults). Our findings demonstrated that (1) that MD and %MD values doubled at a 9-week interval
there was considerable variation among studies reporting (5.7 kg and 11.8%) compared with a 7-day interval (3.1 kg
MD and %MD across each age group; (2) the mean MD and 6.6 %). Abe et al. (2018) observed that although this
(%MD) values were 1.9 kg (25.4%) in young children (<7 test was performed on a different population, the MD
years old), 2.5 kg (13.8%) in children (7 - 10 years old), 4.2 and %MD values were greater at a 1-year interval (6.4 kg
kg (17.1%) in adolescents (10 - 18 years old), 4.0 kg and 21.1 %) than at a 24-hour interval (3.97 kg and 10.1 %).
(11.6%) in young adults (18 - 35 years old), and 4.7 kg However, Jenkins and Cramer (2017) reported similar MD
(16.7%) in older adults (>60 years old); (3) no studies have values at 12- and 24-week intervals, making it unclear
compared the MD and %MD between participants with and whether and at what point extending the interval affects
without sports experience; (4) neither age, test-retest inter- grip strength reproducibility. Grip strength is one part of a
val, nor handgrip device served as significant moderators physical fitness test taken annually for children and adoles-
of MD and %MD reliability. cents. Future studies may clarify the impact of extending
In this study, our meta-analysis found no evidence the test-retest interval on the reproducibility of grip
that the MD and %MD in test-retest reliability for grip strength measurements.
strength measurements were influenced by age. One possi- About 70% of the included studies utilized the
ble reason is the considerable variation in MD and %MD Jamar hand dynamometer, regarded as the gold standard or
among studies within each age group (Figure 2 and Table the Takei dynamometer. In both Jamar and Takei, despite
4). Nonetheless, the mean %MD for the reliability of test- differing standardized measurement conditions (sitting vs.
retest grip strength measures in each age group is distinc- standing, elbows at 90 degrees vs. extended, five grip
tive and partly similar to the %MD observed for muscle widths vs. adjustments for hand size), the type of device
strength measures other than grip strength. For instance, did not affect MD and %MD in grip strength measurements.
maximal voluntary isokinetic muscle strength is a standard Furthermore, several studies examining the measurement
outcome measure for assessing knee joint function. A study accuracy of different handgrip dynamometers using Jamar
measured knee extension and flexion peak torque at an an- as a benchmark also reported a good correlation between
gular velocity of 60 degrees per second across two sessions, the two (Cildan Uysal et al., 2022; Hamilton et al., 1992;
7 days apart, involving 22 children (10 boys and 12 girls) Trajkovic et al., 2024). However, the mechanical systems
with a mean age of 8.8 years (Fagher et al., 2016). The MD of the devices differ between Jamar (hydraulic) and Takei
Abe et al. 551

(Smedley), and it has been observed that the measured val- Abe, T., Sanui, R., Sasaki, A., Ishibashi, A., Daikai, N., Shindo, Y., Abe,
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in participants with high grip strength (Abe et al., 2019). Journal of Clinical Medicine 13(11), 479-488.
Studies reporting test-retest reliability of grip strength https://doi.org/10.4236/ijcm.2022.1311035
measurement in young children are limited to studies using Abe, T., Machida, S., Nakamura, M., Kohmura, Y., Suzuki, K., Abe, A.,
Nakano, M., Loenneke, J. P. and Naito, H. (2024) Tracking
the Takei dynamometer. handgrip strength in Kendo athletes from university to middle
In this study, sex and sports experience were not and older adulthood. American Journal of Human Biology 36(9),
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Garcia-Hermoso, A., Agostinis-Sobrinho, C., Alonso-Martinez,
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Assink, M. and Wibbelink, C. J. (2016) Fitting three-level meta-analytic
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suggest this possibility (Table 4), although future studies Balogun, J. A., Adenlola, S. A. and Akinloye, A. A. (1991) Grip strength
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search may be required to clarify whether sports experience Beauchamp, M. K., Hao, Q., Kuspinar, A., D’Amore, C., Scime, G., Ma,
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L. and Raina, P. (2021) Reliability and minimal detectable
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Acknowledgements https://doi.org/10.1097/MCO.0000000000000202
The authors have no conflict of interest to declare. This study received no Bohannon, R. W. (2017) Test-retest reliability of measurements of hand-
specific grants, fellowships, or materials gifts from any funding agency in grip strength obtained by dynamometry from older adults: A
the public, commercial, or not-for-profit sectors. The datasets generated systematic review of research in the PubMed Database. Journal
during and/or analyzed during the current study are not publicly available of Frailty & Aging 6(2), 83-87.
but are available from the corresponding author who organized the study. https://doi.org/10.14283/jfa.2017.8
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Stenholm, S., Tiainen, K., Rantanen, T., Sainio, P., Heliovaara, M.,
Impivaara, O. and Koskinen, S. (2012) Long-term determinants AUTHOR BIOGRAPHY
of muscle strength decline: Prospective evidence from the 22- Takashi ABE
year Mini-Finland follow-up survey. Journal of American Employment
Geriatrics Society 60(1), 77-85. https://doi.org/10.1111/j.1532-
5415.2011.03779.x
Institute of Health and Sports Science & Medicine, Juntendo
Suzuki, Y., Kamide, N., Kitai, Y., Ando, M., Sato, H., Yoshitake, S. and University
Sakamoto, M. (2019) Absolute reliability of measurements of Degree
muscle strength and physical performance measures in older PhD
people with high functional capacities. European Geriatrics Research interests
Medicine 10(5), 733-740. https://doi.org/10.1007/s41999-019- Exercise physiology and adaptation by exercise training
00218-9 E-mail: t12abe@gmail.com
Svensson, E., Waling, K. and Hager-Ross, C. (2008) Grip strength in
Jun Seob SONG
children: Test-retest reliability using Grippit. Acta Paediatrica
97(9), 1226-1231. Employment
https://doi.org/10.1111/j.1651-2227.2008.00895.x Department of Counseling, Health and Kinesiology, Texas
Tan, B., Aziz, A. R., Teh, K. C. and Lee, H. C. (2001) Grip strength A&M University-San Antonio
measurement in competitive ten-pin bowlers. Journal of Sports Degree
Medicine Physical Fitness 41(1), 68-72. PhD
Trajkovic, N., Rancic, D., Ilic, T., Herodek, R., Korobeynikov, G. and Research interests
Pekas, D. (2024) Measuring handgrip strength in school children:
Skeletal muscle physiology
Inter-instrument reliability between Takei and Jamar. Scientific
Reports 14(1), 1074. https://doi.org/10.1038/s41598-024-51368- E-mail: jsong1@tamusa.edu
1
554 Absolute grip strength test-retest reliability

Scott J. DANKEL
Employment
Department of Health and Exercise Science, Rowan Univer-
sity
Degree
PhD
Research interests
Exercise physiology and statistics
E-mail: dankel47@rowan.edu
Ricardo B. VIANA
Employment
Institute of Physical Education and
Sport, Federal University of Ceará
Degree
PhD
Research interests
Exercise physiology and human anat-
omy
E-mail: vianaricardoborges@ufc.br
Akemi ABE
Employment
Division of Children’s Health and Exercise Research, Institute
of Trainology
Degree
BS
Research interests
Active play and health in children
E-mail: amyabe3379@gmail.com
Jeremy P. LOENNEKE
Employment
Department of Health, Exercise Science, and Recreation Man-
agement, The University of Mississippi
Degree
PhD
Research interests
Skeletal muscle physiology
E-mail: jploenne@olemiss.edu

 Takashi Abe, PhD

Institute of Health and Sports Science & Medicine, Juntendo
University, 1-1 Hirakagakuendai, Inza-shi, Chiba 270-1695,
Japan