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Hand-grip strength of young men, women and highly trained female athletes

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Hand-grip strength has been identified as one limiting factor for manual lifting and carrying loads. To obtain epidemiologically relevant hand-grip strength data for pre-employment screening, we determined maximal isometric hand-grip strength in 1,654 healthy men and 533 healthy women aged 20–25 years. Moreover, to assess the potential margins for improvement in hand-grip strength of women by training, we studied 60 highly trained elite female athletes from sports known to require high hand-grip forces (judo, handball). Maximal isometric hand-grip force was recorded over 15 s using a handheld hand-grip ergometer. Biometric parameters included lean body mass (LBM) and hand dimensions. Mean maximal hand-grip strength showed the expected clear difference between men (541 N) and women (329 N). Less expected was the gender related distribution of hand-grip strength: 90% of females produced less force than 95% of males. Though female athletes were significantly stronger (444 N) than their untrained female counterparts, this value corresponded to only the 25th percentile of the male subjects. Hand-grip strength was linearly correlated with LBM. Furthermore, both relative hand-grip strength parameters (F max/body weight and F max/LBM) did not show any correlation to hand dimensions. The present findings show that the differences in hand-grip strength of men and women are larger than previously reported. An appreciable difference still remains when using lean body mass as reference. The results of female national elite athletes even indicate that the strength level attainable by extremely high training will rarely surpass the 50th percentile of untrained or not specifically trained men.
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ORIGINAL ARTICLE
Hand-grip strength of young men, women and highly trained
female athletes
D. Leyk Æ W. Gorges Æ D. Ridder Æ M. Wunderlich Æ
T. Ru
¨
ther Æ A. Sievert Æ D. Essfeld
Accepted: 27 October 2006 / Published online: 22 December 2006
Springer-Verlag 2006
Abstract Hand-grip strength has been identified as
one limiting factor for manual lifting and carrying
loads. To obtain epidemiologically relevant hand-grip
strength data for pre-employment screening, we
determined maximal isometric hand-grip strength in
1,654 healthy men and 533 healthy women aged 20–
25 years. Moreover, to assess the potential margins for
improvement in hand-grip strength of women by
training, we studied 60 highly trained elite female
athletes from sports known to require high hand-grip
forces (judo, handball). Maximal isometric hand-grip
force was recorded over 15 s using a handheld hand-
grip ergometer. Biometric parameters included lean
body mass (LBM) and hand dimensions. Mean maxi-
mal hand-grip strength showed the expected clear dif-
ference between men (541 N) and women (329 N).
Less expected was the gender related distribution of
hand-grip strength: 90% of females produced less force
than 95% of males. Though female athletes were sig-
nificantly stronger (444 N) than their untrained female
counterparts, this value corresponded to only the 25th
percentile of the male subjects. Hand-grip strength was
linearly correlated with LBM. Furthermore, both rel-
ative hand-grip strength parameters (F
max
/body weight
and F
max
/LBM) did not show any correlation to hand
dimensions. The present findings show that the differ-
ences in hand-grip strength of men and women are
larger than previously reported. An appreciable dif-
ference still remains when using lean body mass as
reference. The results of female national elite athletes
even indicate that the strength level attainable by ex-
tremely high training will rarely surpass the 50th per-
centile of untrained or not specifically trained men.
Keywords Strength Gender Trainability
Lean body mass Ergonomic references
Introduction
Manual lifting and carrying of loads are common types
of exercise in everyday life at home and at work. De-
spite the application of high technology at work, there
are still physically demanding occupations in fields
such as automotive industries, manual material han-
dling jobs, postal, emergency and military services. In
the last two decades there has been a large increase in
the number of women employed in these traditionally
male-dominated occupations (Bhambhani and Maikala
2000; Haward and Griffin 2002). Generally, the abso-
lute loads to be handled on the job are similar for men
and women (Bhambhani and Maikala 2000; Rice et al.
1996a). Since hand-grip strength has been identified
as a limiting factor for manual carrying (Bhambhani
and Maikala 2000; Bystro
¨
m and Fransson-Hall 1994;
D. Leyk W. Gorges
Department IV-Military Ergonomics and Exercise
Physiology, Central Institute of the Federal Armed Forces
Medical Services Koblenz, Andernacher Strasse 100,
56070 Koblenz, Germany
D. Ridder
FGAN e.V. - Research Institute for Communication,
Information Processing and Ergonomics,
Neuenahrer Strasse 20, 53343 Wachtberg, Germany
D. Leyk (&) M. Wunderlich T. Ru
¨
ther
A. Sievert D. Essfeld
Department of Physiology and Anatomy,
German Sport University Cologne,
Carl-Diem-Weg 6, 50933 Cologne, Germany
e-mail: Leyk@dshs-koeln.de
123
Eur J Appl Physiol (2007) 99:415–421
DOI 10.1007/s00421-006-0351-1
Kilbom et al. 1992; Knapik et al. 1999; Rice et al.
1996a, b; von Restorff 2000), assessment of hand-grip
strength could be used for pre-employment screening
and selection.
For a given hand-grip ergometer, measurements are
reliable, safe, easy and fast to perform (Haidar et al.
2004; Haward and Griffin 2002; Leyk et al. 2006;
Rantanen et al. 1998). Moreover, normative hand-grip
strength data are not only essential for the prevention
of manual lifting hazards, but also of paramount
importance in determining the effectiveness of various
surgical or treatment procedures (Mathiowetz et al.
1985; Rauch et al. 2002).
Despite its fundamental importance for occupa-
tional and clinical practice, only few studies provided
hand-grip strength data of large study populations,
typically in the order of some 100 healthy individuals
(Bao and Silverstein 2005; Barnekow-Bergkvist et al.
1996; Haidar et al. 2004; Hanten et al. 1999; Kallman
et al. 1990; Kellor et al. 1971; Massy-Westropp et al.
2004; Mathiowetz et al. 1985; Sinaki et al. 2001).
However, these data have to be interpreted with some
caution as recently suggested by Luna-Heredia et al.
(2005). All studies comprised study populations of men
and women with age spans of many decades. For epi-
demiological purposes the investigated numbers of
subjects were too small for a detailed age and gender
related stratification. Since hand-grip strength is influ-
enced by various factors (gender, age, physical fitness,
etc.), reference values for hand-grip strength should be
determined in large and well-characterized groups.
The present study has three major aims: (1) in order
to provide epidemiologically relevant normative hand-
grip strength data for pre-employment screening and
selection, we investigated young, healthy women and
men aged between 20 and 25 years. (2) To evaluate the
potential influence of biometric factors on hand-grip
strength, anthropometric measures such as hand
length, hand width and lean body mass were taken
from the subjects. (3) It is well known that women
possess considerably smaller absolute muscle strength
than men. When women have to be assigned to phys-
ically demanding workplaces with similar absolute
loads for both sexes (e.g. military services, fire fighter),
it is of paramount importance to estimate the potential
margin of improvement in muscle strength by exercise
and training. Therefore, we investigated highly trained
female athletes from sports, which are known to re-
quire high hand-grip strength (judo and handball).
Such collectives of female elite athletes provide an
excellent opportunity to study the strength level
attainable by daily physical training over years. The
results from these elite athletes can serve as a measure
for the maximal trainability attainable for young,
healthy women.
Methods
Subjects
Our nationwide recruited study sample comprised
2,247 young healthy adults (1,654 men, 533 women and
60 female national elite athletes). The subjects of the
non-athlete groups were untrained or not specifically
trained young adults with a typically German educa-
tion distribution as estimated by the latest official
census (Mikrozensus 2004). This group covers the
whole range of employment status from jobless persons
without any certificate, up to employed persons and
university students. The female elite athletes were
members of national teams.
The basic characteristics are shown in Tables 1 and 2.
Prior to examination the volunteers were informed
about the purpose and the procedures of the investiga-
tion and gave their written consent. Additional infor-
mation about the athletics status of all participants was
assessed by means of a questionnaire. All subjects were
familiarized with the test procedures and were tested to
obtain anthropometric and hand-grip strength data. The
study was approved by the Ethics Committees of the
German Sport University and the Medical Association
of the Federal State Rhineland-Palatinate, Germany.
Anthropometry
In addition to body height and body weight additional
information about the percentage of body fat could be
assessed in 1,553 men, 482 women and in all female
athletes. For that purpose the skinfold thickness at four
sites—biceps, triceps, subscapular and suprailiac—was
determined by means of Harpenden calipers (Har-
penden Skinfold Caliper HSK-BI, British Indicators,
West Sussex, United Kingdom). Values were measured
three times to the nearest 0.2 mm. If results deviated
more than 1.0 mm, the three measurements were re-
peated. The sum of the four skinfold measurements
was evaluated according to the equations of Durnin
and Womersley (1974). Absolute and percent lean
body mass (LBM) were calculated from body fat (%)
and body weight (kg):
LBM ð%Þ¼½100 fat ð%Þ;
LBM ðkgÞ¼
weight LBM ð%Þ
100

416 Eur J Appl Physiol (2007) 99:415–421
123
To evaluate the relationship between LBM and
maximum hand-grip strength LBM-groups were as-
signed to ten consecutive 5-kg-classes ranging from 35
to 85 kg.
Hand-grip force
Maximal isometric hand-grip force was recorded over
15 s using a handheld hand-grip ergometer shown in
Fig. 1. Force (F) was measured by a strain gauge sensor
(K-2565, Lorenz Messtechnik Ltd., Alfdorf, Germany;
measuring range: 1,500 N; accuracy: 0.1%) at a sam-
pling frequency of 50 Hz (750 data points for each 15 s
test). During measurement, upper and lower arm were
supported in such a way that a 90 position of the el-
bow joint was achieved without additional effort
(Fig. 2). The following parameters were derived from
the 15 s force tracings:
(1) Maximum hand-grip force (F
max
): the maximum
value out of all 750 data points for each 15 s test.
(2) Mean hand-grip force (F
mean
): the arithmetic
average of the 750 data points.
(3) Percent F
mean
(pF
mean
): F
mean
expressed as per-
centage of F
max
.
(4) Relative hand-grip forces: F
max
per kg body mass
or LBM.
To assess the potential influence of hand dimensions
on hand-grip strength, hand length and width were
measured in 1,142 male and 338 female volunteers as
described by Ju
¨
rgens (2000) and Martin et al. (1991).
Statistical analyses
Statistical analyses were performed using SPSS
TM
12.1
and STATISTICA
TM
7.1. Data are generally given as
Table 1 Anthropometric characteristics of young adult men and women
Variables Mean (SD) 5th 25th Median 75th 95th
Men
n = 1,654 Age (year) 21.4 (1.4) 20 20 21 22 24
n = 1,654 Weight (kg) 78.2* (12.1) 61.74 69.80 76.65 84.90 100.90
n = 1,654 Height (cm) 180* (0.7) 169 175 180 185 191
n = 1,654 BMI (kg m
–2
) 24.1* (3.3) 19.67 21.84 23.75 25.86 30.26
n = 1,553 Fat (%) 18.7* (5.9) 9.95 14.18 18.08 23.01 28.79
n = 1,553 Lean body mass (kg) 63.2* (7.1) 52.62 58.27 62.73 67.76 75.60
Women
n = 533 Age (year) 21.5 (1.4) 20 20 21 22 24
n = 533 Weight (kg) 64.1 (11.2) 51.06 56.70 62.60 69.50 82.43
n = 533 Height (cm) 167 (0.6) 158 163 167 171 178
n = 533 BMI (kg m
–2
) 23.0 (3.7) 18.74 20.59 22.45 24.78 28.56
n = 482 Fat (%) 30.8 (5.5) 22.34 26.78 30.45 34.95 40.05
n = 482 Lean body mass (kg) 43.7 (4.5) 37.33 40.45 43.39 46.26 51.47
Values are means ± SD and percentile ranges
*P < 0.001, significant between gender
Table 2 Anthropometric data of national female elite athletes
Variable All athletes (n = 60) Range Judo (n = 45) Range Handball (n = 15) Range
Age (years) 19.8 ± 4.1 15–31 18.8* ± 3.4 15–31 22.6 ± 4.7 16–30
Height (cm) 171 ± 0.5 157–182 171 ± 0.6 157–182 172 ± 0.5 165–180
Weight (kg) 71.2 ± 13.3 53.6–130.6 72.5 ± 15.0 53.6–130.6 68.7 ± 4.8 61.9–80.0
BMI (kg m
–2
) 24.2 ± 3.8 18.3–40.3 24.5 ± 4.11 18.3–40.3 23.3 ± 2.3 20.1–28.7
Fat (%) 26.4 ± 5.6 15.3–43.9 26.7 ± 5.7 16.6–43.9 25.6 ± 5.5 15.3–34.9
Lean body mass (kg) 51.9 ± 6.1 40.0–73.4 52.2 ± 6.9 40.0–73.4 51.0 ± 2.7 45.2–54.3
Values are means ± SD and absolute range (n = 60)
*Significant between the athlete groups (P < 0.01)
Fig. 1 Hand-grip ergometer: length 150 mm; mass 1.1 kg
Eur J Appl Physiol (2007) 99:415–421 417
123
means and standard deviation (SD). The comparisons
of hand-grip strength data between the male and fe-
male control group and the trained female subjects are
presented as median and interquartile range (box-
plot). Independent Mann–Whitney u-test was used to
compare average hand-grip forces and anthropometric
data. The mean time courses of hand-grip force were
investigated by two-way ANOVA for repeated mea-
sures (factors ‘‘gender’’ and the 15 s ‘‘test-time’’).
Maximum hand-grip force values of different LBM-
groups were analysed by two-way ANOVA (factors
‘‘gender’’ and ‘‘LBM-groups’’). The Newman–Keuls
test was used for post hoc comparisons. Linear
regression and Spearman correlation coefficients were
computed for F
max
and LBM-values as well as for F
max
and pF
mean
of men and women, respectively. In addi-
tion, multiple regression analysis was applied to
investigate the influence of gender and anthropometric
characteristics on hand-grip force. The backward
analysing method was used. Significance level was
chosen as P = 0.01.
Results
Relevant anthropometric characteristics of the young
adult control groups are shown in Table 1. With the
exception of age all biometric values revealed signifi-
cant differences between men and women (P < 0.001).
Hand-dimensions had no significant influence on
hand-grip strength per kg body mass (F
max
/body
weight). This applies to both hand length (men: r =
–0.03, P = 0.196; women: r = 0.12, P = 0.027) and hand
width (men: r = –0.01, P = 0.745; women: r = 0.03,
P = 0.471). Furthermore, analysis of variance revealed
a significant effect of gender (P < 0.0001) but not for
hand length or hand width (P = 0.286, P = 0.390).
Similar results were obtained when using hand-grip
strength per kg LBM (F
max
/LBM) as reference.
Maximal (men: 540.8 ± 87.1; women: 329.4 ±
57.7 N) and mean hand-grip force (men: 460.5 ± 79.4;
women: 277.8 ± 52.8 N) differed significantly between
males and females. Figure 3 shows the mean time
courses of hand-grip force of the male and female
volunteers (n = 2,187). Analysis of variance yielded a
significant effect of ‘‘test time’’ (force time course,
P < 0.001), a significant influence of gender
(P < 0.001) and a statistically relevant interaction of
the two factors (P < 0.001). When expressed as %
F
max
, the mean hand-grip force over 15 s of men and
women showed only a negligible, though statistically
significant difference (85.1% vs. 84.3%, P < 0.01).
However, there was no indication of relationship be-
tween F
max
and pF
mean
r = 0.10 (Y = 83.22 + 0.004 ·
F
max
, P < 0.0001, n = 2,187): subjects with high, mod-
erate or low maximum grip-force values sustained
comparable percentage values of their hand-grip force
maximum during the test interval (distribution: med-
ian = 85.6%, fifth percentile = 76.0%, 95th percen-
tile = 91.5%, n = 2187).
A more detailed insight into the gender related
hand-grip distribution is given in Fig. 4. 90% of the
female test persons produced maximal hand-grip forces
smaller than the values of 95% of their male counter-
parts. The woman with highest hand-grip force reached
only the 33rd percentile of the male volunteers.
200
300
400
500
F max (N)
0 3 6 9 12 15
time (s)
men women
Fig. 3 Time courses of hand-grip forces of young male (solid
curve) and female (dotted curve) adults aged 20–25 years. Values
are means (men: n = 1,654; women: n = 533). For better
illustration the SD bars are not shown (SD-range of men: 74–
133 N; SD-range of women: 47–72 N)
Fig. 2 Exercise position during the hand-grip test
418 Eur J Appl Physiol (2007) 99:415–421
123
Linear regression analysis revealed that hand-grip
force was strongly associated with absolute lean body
mass (LBM, R
2
= 0.765). The LBM-associated force
increase (Fig. 5) was significant for all LBM-groups
(P < 0.0001), and for the factor gender (P < 0.0001)
with virtually identical slopes in males and females
(P = 0.612) but different Y-intercept (men: Y =
193.8 N + 5.5 N kg
–1
;women:Y = 86.6 N + 5.6 N kg
–1
).
If hand length or hand width are matched between
men and women within an LBM-group of sufficient
overlap (50–54.9 kg, male n = 70, female n = 18) then
the difference in maximum hand-grip strength persists
(about 90 N, P < 0.0001). Spearman correlation coef-
ficients between the variables hand-grip strength and
LBM were r = 0.453 (P < 0.0001, men) and r = 0.440
(P < 0.0001, women). Multiple linear regression anal-
ysis of the independent variables gender, body height
and LBM revealed the following results: gender
(P < 0.0001) and LBM (P < 0.0001) are positively and
linearly related to grip-force values (model R
2
=
0.647). In contrast to LBM, no statistically relevant
influence was found for body height and body fat in
both men and women.
Anthropometric characteristics of the female elite
athletes (judokas and handball players) are given in
Table 2. All parameters differ significantly between
female controls and the trained women. The highly
trained female athletes (F
max
: 443.6 ± 38.2; F
mean
:
374.5 ± 37.9) were stronger than the female control
group but still considerably weaker (P < 0.0001) than
most of the male volunteers (Fig. 6). The strongest
female athlete had a maximal hand-grip force of 559 N
corresponding to the 58th percentile of the male vol-
unteers.
Discussion
The main objective of our study was to establish hand-
grip reference values of young adults for pre-employ-
ment screening and personnel selection. Such norma-
tive data are also needed in clinical practice, e.g.
physiotherapy, hand surgery, pediatrics, gerontology
(Haidar et al. 2004; Luna-Heredia et al. 2005; Ma-
thiowetz et al. 1985; Rauch et al. 2002). In terms of
absolute hand-grip strength our results indicate larger
gender differences than previously reported (Laubach
1976; Heyward et al. 1986; Miller et al. 1993; Sinaki
et al. 2001). Ninety percent of the women had lower
F
max
values than 95% of the male control group
(Fig. 4). The strongest female volunteer of our control
group only achieved a maximal hand-grip value of only
505 N, which was exceeded by 2/3 of all men. The age-
heterogeneity of other hand-grip force focusing study
populations, covering up to eight decades, inevitably
results in larger data scatter and overlaps between
males and females (Kallman et al. 1990; Haward and
Griffin 2002; Mathiowetz et al. 1985).
A significant gender difference of about 90 N per-
sisted when maximal hand-grip strength was related to
lean body mass (Fig. 5). This difference cannot be
attributed to an inappropriate choice of ergometer
dimensions since no influence of hand length or width
could be detected. Clerke et al. (2005), who compared
male and female teenagers, also failed to find signifi-
cant effects of hand shape on maximal grip strength.
Some studies indicate that sex-related strength differ-
ences are more pronounced in the upper body (Hey-
ward et al. 1986; Laubach 1976; Miller et al. 1993).
Therefore, the strength difference of Fig. 5 might at
least partly be attributed to the fact that women tend to
have a lower portion of their lean body mass located in
the upper body (Miller et al. 1993). With regard to
manual load-carriage tasks in the work environment,
this would mean that women have to lift and carry
loads with a smaller fraction of their already smaller
absolute muscle mass.
An example of a demanding manual exercise is
stretcher transport (Barnekow-Bergkvist et al. 2004;
Gamble et al. 1991; Knapik et al. 1999; Leyk et al.
2006). The sustained isometric hand-grip contraction
and the eccentric strains during the transport require
large hand-grip strength of ambulance personnel (Leyk
et al. 2006). With regard to personnel selection
and recruiting procedures for medical services, von
0
20
40
60
80
100
cumulative percentage
200 400 600 800
F max (N)
men
women
Fig. 4 Distribution of maximum hand-grip forces (F
max
) of male
(solid curve) and female (dotted curve) volunteers (men:
n = 1,654; women: n = 533)
Eur J Appl Physiol (2007) 99:415–421 419
123
Restorff (2000) proposed to consider only candidates
whose grip strength at the weaker side exceeds 334 N.
It can be taken from Fig. 4 that about 60% of our
female volunteers would not have sufficient grip
strength to meet this criterion.
Multivariate regression model including body
height, gender and LBM revealed no relationship be-
tween body height and hand-grip strength. This is a
remarkable difference to the approach of Frederiksen
et al. (2006) who described body height-stratified
reference data. However, body weight, body fat and
LBM were not measured in their study. The results of
our broader approach, including the aforementioned
biometric parameters revealed that hand-grip strength
is not causally affected by body height per se, but ra-
ther predicted by LBM.
One might expect that strength training of women
could eliminate the strength difference at least with
regard to a group of not specifically trained males
(Fig. 6). To our own surprise, the female elite athletes,
though active in sports (handball and judo) where hand-
grip strength is trained in each training session matched
only the 25th percentile of the male control group.
We also observed that, independent of the strength
level and for both sexes, volunteers were able to sus-
tain about 85% of their individual F
max
during the 15 s
hand-grip tests. Since maximal hand-grip tests strongly
depend on cooperation and motivation of the test
persons, the relation of the sustained and maximal
hand-grip strength could be used to control data
quality.
In conclusion, we found considerable differences in
hand-grip strength between young male and female
adults. The mean maximal hand-grip force differs by
more than 200 N, with only a small overlap of strength
distribution and no significant influence of hand size.
Appreciable differences in the order of 100 N remain
when using lean body mass as reference. Surprisingly,
even the group of highly trained female athletes mat-
ched only the 25th percentile of our untrained or not
specifically trained male controls.
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... Hand-grip strength (HGS)-a simple, quick, reliable, and inexpensive method for measuring strength-is used for measuring the overall muscle strength in older adults and is known to be correlated with leg strength 7,8 . Recent studies have proved the validity of using hand dynamometers to assess health and nutritional status 9,10 , and several previous studies have used HGS as a proxy measure for muscle function and physical health 2,[11][12][13] . HGS measurement is increasingly common as a clinically viable screening tool for determining muscle weakness and detecting other clinically relevant health outcomes 1 . ...
... The participants in the KLoSA were asked to squeeze the dynamometer twice for each hand in a sitting position, and the mean value of four trials was recorded. Since previous studies have confirmed that HGS is significantly different in men and women 13,23 , we analyzed the data by stratification according to sex. In the present study, HGS was analyzed as a categorical variable according to the criteria presented by the AWGS in 2019. ...
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We investigated the association between working status changes and hand-grip strength (HGS) among middle-aged and older Korean adults using data from the 2006–2018 Korean Longitudinal Study of Aging. After excluding those with less than normal HGS in the baseline year, newly added panels, and missing values, 3843 participants (2106 men; 1737 women) were finally included. After adjusting for potential confounders, we used a 2-year lagged multivariable generalized estimating equation model to examine this association longitudinally. Men who quit working or who continued to be non-working were more likely to have lower HGS than those who continued to work (working → non-working, adjusted odds ratio [OR]: 1.47, 95% confidence interval [CI] 1.26–1.70; non-working → non-working, adjusted OR: 1.52, 95% CI 1.34–1.72). Compared to women who continued to work, the other three groups showed high ORs with low HGS (working → non-working, adjusted OR: 1.19, 95% CI 1.01–1.40; non-working → working, adjusted OR: 1.18, 95% CI 0.98–1.42; non-working → non-working, adjusted OR: 1.38, 95% CI 1.22–1.56). Middle-aged and older adults whose working status changed to non-working were at higher risk of reduced HGS than others and required muscular strength training interventions to improve HGS and prevent sarcopenia.
... A similar finding was demonstrated in a study on the French population [58]. Another study on 20-25 year-old young German males and females demonstrated similar findings where gender significantly influenced handgrip power [59]. The apparent difference in handgrip power between males and females could have influenced the handgrip power. ...
... Another study on Bangladeshi cricket team batters showed a significant correlation between the handbreadth and handgrip power for both hands [61]. On the contrary, the study on the 20 to 25-year-old German population did not significantly affect hand length and handbreadth on handgrip power [59]. The forward selection method was adopted for multiple regression in the current study, where a variable was selected to enter the model if p ≤ 0.05. ...
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Background Handgrip power is an essential indicator of health, vital for grasping or gripping sports, and crucial for providing information related to work capacity. The present study investigated any linear relationship of handgrip power with hand anthropometric variables (hand length, handbreadth, middle finger length, second inter-crease length of the middle finger, and hand span), gender, and ethnicity in young adults of Sabah. Methods In this cross-sectional study (from January 2020 to December 2021), the adult Sabahan population (18-25 years) was stratified into four ethnicities (KadazanDusun, Bajau, Malay, and Chinese) and was further stratified as males and females. Then, 46 subjects were randomly selected from each gender, and the ethnic group met the intended sample size. The hand dimensions were measured using a digital calliper, and the handgrip power was measured using a portable dynamometer. The relationship between the response variable and explanatory variables was analyzed at first through simple linear regression and then multiple linear regression. R ² , adjusted R ² , and standard errors of the estimates were used to compare different models. Statistical analyses were performed using IBM SPSS Statistics 27 and StatCrunch. Results The study found a linear relationship between gender, height, hand length, handbreadth, hand span, middle finger length, and second inter-crease length of both hands with the corresponding hand’s grip power. The highest percentage (68% and 67%) of handgrip variability was demonstrated by the model predicting handgrip power for right-handed subjects, followed by the general models without stratifying based on hand dominance which was able to explain 63% and 64% of the variability of handgrip power. The study proposes the models for predicted right (RHGP) and left handgrip power (LHGP) of 18 to 25 years old adults from major ethnic groups of Sabah RHGP = − 18.972 − 8.704 Gender + 7.043 Right hand breadth and LHGP = − 11.621 − 9.389 Gender + 5.861 Left hand breadth respectively. Conclusion The predicted handgrip power would be a key to selecting a better player or a better worker or assessing the prognosis of a disease or the wellbeing of a person. The study can be further expanded to all ethnicities and ages of people of Sabah or even Malaysia.
... Therefore, a decrease in type II muscle fiber responsiveness in women has been suggested as a reason for the increased incidence of falls in females compared to males [19]. Furthermore, a study by Leyk et al. found that female athletes, despite being highly trained in handgrip active sports, matched only the 25th percentile of athletically untrained men [20]. This study calls into question the potential differences in muscle composition between males and females. ...
... Muscle fitness is crucial in military service. To measure physical fitness, the hand grip strength test is easy to perform and it is widely used to measure upper body muscle fitness in all age groups [32][33][34][35][36][37] and is often used as an indicator of general health. Carswell et al. [4] found evidence that low 25(OH)D levels were negatively related to muscle fitness in the UK army. ...
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Background: There has been a growing interest in the role of vitamin D for the well-being and physical performance of humans under heavy training such as conscripts in military service; however, there is a lack of long-term supplementation studies performed on members of this type of young, physically active, male population. The hypothesis of the study was that vitamin D supplementation during wintertime will decrease the prevalence of critically low vitamin D blood serum levels and increase hand grip strength during the winter season among young male conscripts. Study design: Longitudinal, triple-blinded, randomized, placebo-controlled trial. Methods: Fifty-three male conscripts from the Estonian Army were randomized into two groups: 27 to an intervention group and 26 to a placebo group. The groups were comparable in terms of their demographics. The intervention group received 1200 IU (30 µg) capsules of vitamin D3, and the control group received placebo oil capsules once per day. The length of the follow-up was 7 months, from October 2016 until April 2017. Blood serum vitamin D (25(OH)D), parathyroid hormone (PTH), calcium (Ca), ionized calcium (Ca-i), testosterone and cortisol values, and hand grip strength were measured four times during the study period. Results: The mean 25(OH)D level decreased significantly in the control group to a critically low level during the study, with the lowest mean value of 22 nmol/l found in March 2017. At that time point, 65% in the control group vs 15% in the intervention group had 25(OH)D values of less than 25 nmol/l (p < 0.001). In the intervention group, the levels of 25(OH)D did not change significantly during the study period. All other blood tests revealed no significant differences at any time point. The corresponding result was found for hand grip strength at all time points. Conclusion: Long-term vitamin D supplementation during wintertime results in fewer conscripts in the Estonian Army with critically low serum vitamin D (25(OH)D) levels during the winter season. However, this did not influence their physical performance in the form of the hand grip strength test.
... According to Leyk et al., men have a larger mean maximum HGS than women. [12] Heyward et al. observed that gender strength disparities are more noticeable in the upper body because men had higher muscular mass than women. [13] According to Shah et al., healthy adult males have better HGS than females. ...
... This is explained with the increased muscle mass in high level athletes. Also, lean body mass is stated to be significantly associated with HGS performance (Leyk et al., 2007). ...
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The aim of this study was to determine and compare maximal handgrip strength (HGS) of international and national level judo athletes. Eighteen international and 16 national level judo athletes voluntarily participated in this study. After anthropometric measurements, athletes performed the maximal isometric HGS test three times on each side with a 1-min interval between attempts. Independent sample T test was used to compare groups and Pearson correlation coefficient was calculated to determine the relationship between variables. Significance was set at p<0,05. There was significant difference in body mass, height, body mass index, right, left and sum relative maximal HGS between groups (p<0,05). No other significant difference was observed. As for correlations among variables, there were significant correlations between body mass and maximal HGS (p=0.00). Also, there were significant correlations between body mass index and maximal HGS (p=0,00). According to classificatory table, most of the athletes were classified as regular for right hand absolute and relative, left hand absolute and relative and sum absolute and relative maximal HGS. International-level judo athletes presented better maximal isometric HGS than national judo athletes given absolute power they produced while national judo athletes presented better results in relative HGS. Uluslararası ve ulusal seviyedeki Türk judocuların maksimal izometrik el kavrama kuvvetleri Özet Bu çalışmanın amacı uluslararası ve ulusal seviyedeki judocuların maksimal el pençe kuvvetini belirlemek ve karşılaştırmaktır. Çalışmaya 18 uluslararası ve 16 ulusal seviyede erkek sporcu gönüllü olarak katıldı. Antropometrik ölçümler sonrasında sporcular 1 dakika ara ile her el için rastgele 3 kez maksimal el pençe kuvvet testini gerçekleştirdi. Grupların performanslarını karşılaştırmak için bağımsız örneklemlerde T test kullanılırken, değişkenler arasındaki ilişkiyi belirlemek için Pearson korelasyon testi kullanıldı. Analamlılık düzeyi p<0,05 olarak kabul edildi. Gruplar arasında vücut ağırlığı, boy, vücut kütle indeksi, sağ, sol ve toplam rölatif el pençe kuvvetinde anlamlı farklılık tespit edildi (p<0,05). değişkenler arasındaki ilişki incelendiğinde, vücut ağırlığı ve vücut kütle indeksi ile maksimal el pençe kuvveti arasında anlamlı ilişki tespit edildi (p=0,00). Sınıflandırma tablosu ile değerlendirildiğinde, sporcuların çoğu sağ mutlak ve rölatif, sol mutlak ve rölatif ve toplam mutlak ve rölatif el pençe kuvvetinde sıradan olarak sınıflandırıldı. Mutlak el pençe kuvveti düşünüldüğünde, uluslararası seviyedeki sporcular ulusal seviyedeki sporculardan daha iyi performans ortaya koydu, ancak ulusal seviyedeki sporcular rölatif performansta daha iyi sonuçlar ortaya koymuştur.
... 24) Falsarella et al. 25) evaluated the effect of muscle mass on the functionality of 99 older women and observed that decreased muscle mass was associated with walking speed and poor physical performance on TUG tests. Leyk et al. 26) found that HGS is highly correlated with lean body tissue. Studies have shown that BMI is weakly correlated with HGS. ...
Article
Background Obesity is pathophysiologically complex in older adults compared to that in young and middle-aged adults. The aim of the present study was to determine the appropriate body mass index (BMI) range based on geriatric evaluation parameters in which complications can be minimized in older adults. Methods A total of 1,051 older adult patients who underwent comprehensive geriatric assessment were included. The patients’ demographic characteristics, comorbid diseases, number of drugs, BMI, basic and instrumental activities of daily living (BADL and IADL), Tinetti balance and walking scale, Mini Nutritional Assessment, Geriatric Depression Scale-15, Mini-Mental State Examination, Time Up and Go test, and handgrip strength measurement were extracted from patient records. Results Of the patients who took part, 73% were female, and the mean age was 77.22±7.10 years. The most negative results were observed in those with a BMI <25 kg/m2 and in those with a BMI >35 kg/m2. Receiver operating characteristic (ROC) analysis of the optimum BMI cutoff levels to detect the desirable values of geriatric assessment parameters was found to be 31–32 and 27–28 kg/m2 for female and male, respectively. Conclusion Older adults with BMI <25 and >35 kg/m2 were at a higher risk of a decrease in functional capacity, and experienced gait and balance problems, fall risk, decrease in muscle strength, and malnutrition. Data from this study suggest that the optimum range of BMI levels for older adults is 31–32 and 27–28 kg/m2 for female and male, respectively.
... These findings are in line with those of Kalichman et al., who studied the association of midshaft enthesophytes and osteophytes and found that age corresponded to 45% of enthesophyte variation in males but only 25% in females [14]. This finding may result from a stronger grip of males compared to females [15] resulting in a more developed pulley system at the fingers and also possibly higher mechanic strain on their insertions. ...
Article
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Objectives: The effects of aging such as osteophyte formation, acral shape changes, cortical tunneling, and bone porosity as well as enthesophytes can be studied in the X-rays of hands. However, during the interpretation of radiographs of the hands, misinterpretation and false-positive findings for psoriatic arthritis often occur because periosteal proliferations of the phalanges are overinterpreted and too little is known about enthesophytes of the phalanges in this area. Method: It included a total of 1153 patients (577 men, 576 women) who presented themselves to the emergency department and received a radiography of their right hand to exclude fractures. The Osseographic Scoring System was used in a modified form to record osteophytes and enthesophytes. A linear regression model for periosteal lesions was computed with age, sex, osteophytes, and global diagnosis as covariables. The inter-reader agreement was assessed using ICC (two-way mixed model) on the sum scores of osteophytes and periosteal lesions. Results: Overall, men exhibited more periosteal lesions, demonstrated by a higher mean sum score of 4.14 vs. 3.21 in women (p = 0.008). In both sexes, the second and third proximal phalanx were most frequently affected by periosteal lesions, but the frequencies were significantly higher in men. The female sex was negatively associated with an extent of periosteal lesions with a standardized beta of -0.082 (p = 0.003), while age and osteophytes were positively associated with betas of 0.347 (p < 0.001) and 0.156 (p < 0.001), respectively. The distribution of osteophytes per location did not differ between men and women (p > 0.05). The inter-reader agreement was excellent for periosteal lesions with ICC of 0.982 (95%CI 0.973-0.989, p < 0.001). Conclusions: Special care should be taken not to confuse normal periosteal changes in aging with periosteal apposition in psoriatic arthritis.
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The objectives of this study were to evaluate the current fitness of an area ambulance service based in Belfast and to quantify the physiological demands of accident and emergency work. From a total staff of 230, 105 (46%) volunteered to undergo a series of fitness tests subject to health state. Results based on body mass indices showed that 52% of subjects could be classified as overweight and 10% of subjects as obese. Fitness levels were similar to other comparable samples and showed the expected but not inevitable decrease with age. A simple work related task (walking at 6 km/h) performed in the laboratory showed that 54% of men over 40 years of age and 24% under 40 found it taxing. This would favour selection for accident and emergency work on the basis of functional capacity rather than chronological age. Accident and emergency work consisted of long periods of inactivity interspersed with shorter periods of relatively intense activity, often above the anaerobic threshold. Lactate concentrations measured during a staged emergency incident also suggested that personnel may work at intensities exceeding their anaerobic threshold. The incorporation of physical fitness standards in the ambulance service may be appropriate and consideration should be given to a reduced age of retirement.
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The primary purpose of this study was to establish clinical norms for adults aged 20 to 75+ years on four tests of hand strength. A dynamometer was used to measure grip strength and a pinch gauge to measure tip, key, and palmar pinch. A sample of 310 male and 328 female adults, ages 20 to 94, from the seven-county Milwaukee area were tested using standardized positioning and instructions. Right hand and left hand data were stratified into 12 age groups for both sexes. This stratification provides a means of comparing the score of individual patients to that of normal subjects of the same age and sex. The highest grip strength scores occurred in the 25 to 39 age groups. For tip, key, and palmar pinch the average scores were relatively stable from 20 to 59 years, with a gradual decline from 60 to 79 years. A high correlation was seen between grip strength and age, but a low to moderate correlation between pinch strength and age. The newer pinch gauge used in this study appears to read higher than that used in a previous normative study. Comparison of the average hand strength of right-handed and left-handed subjects showed only minimal differences.
Article
The purpose of this study was to examine gender differences in upper and lower body strength as a function of lean body weight and the distribution of muscle and subcutaneous fat in the upper and lower limbs. The subjects were 103 physically active men (n = 48) and women (n = 55). The peak torques produced during shoulder flexion (SF) and knee extension (KE) were used as measures of upper body and lower body strength, respectively. Flexed arm girth, thigh girth, triceps skinfold, and thigh skinfold were used to estimate the distribution of muscle and subcutaneous fat in the limbs. Results of the MANOVA revealed that the overall strength of men was significantly greater than that of women. Results of MANCOVA indicated that the SF and KE strength of women and men did not differ significantly when differences in lean body weight, arm girth, thigh girth, triceps skinfold and thigh skinfold were statistically controlled. High levels of SF and KE strength were associated with a high lean body weight and a large arm girth. Results of the multiple regression analysis indicated that for men a substantial portion of the variance in both SF and KE strength was explained by lean body weight alone; whereas strength variations in women were explained more adequately by including limb variables along with lean body weight. Within the limitations of this study, it was concluded that gender differences in upper and lower body strength are a function of differences in lean body weight and the distribution of muscle and subcutaneous fat in the body segments. Upper body strength is relatively more important than lower body strength in characterizing the gender difference in strength.
Article
This study examined repeated, short-distance stretcher carries and the effects of gender, a shoulder harness, and team size on simulated transportation, defense, and medical treatment of patients. Participants carried a 6.8-kg stretcher, loaded with an 81.6-kg manikin, for a distance of 50 m, lifted it onto a simulated ambulance, and returned 50 m to retrieve the next patient. Participants completed as many cycles as possible in 15 min. Dependent measures included number of carries, weapon firing, fine-motor coordination, heart rate, perceived exertion, and physical symptoms. Analysis of variance and post-hoc Newman-Keuls comparison of means revealed that men completed more carries than women (18.0 ± 1.6 vs. 14.5 ± 2.0 carries, p < 0.001), and women reported more upper extremity discomfort (p < 0.05). Harness use resulted in slightly faster fine-motor performance (46.1 ± 8.3 vs. 47.6 ± 7.7 s; p = 0.03) and less discomfort in the upper extremities (p < 0.05) than hand carries. Four-person teams resulted in reduced discomfort in the neck and upper extremity (p < 0.05) and improved post-carry fine-motor coordination (47.6 ± 8.3 vs. 46.0 ± 7.7 s; p = 0.02), as well as increasing weapon firing accuracy for women (p < 0.05). Four-person hand-carry teams completed more carries than any other team-size × harness combination (p < 0.01). For mass-casualty scenarios, four-person teams are recommended. A harness system should be available for two-person and female teams.
Article
This study examined the effects of gender, two- vs. four-person teams, and use of a shoulder harness vs. a hand carry on the ability of participants to simulate the transport of patients during a prolonged stretcher carry, and to simulate the defense and medical treatment of patients following the stretcher carry. Participants carried a 6.8-kg stretcher containing an 81.6-kg manikin at a constant rate of 4.8 km/h for as long as possible, up to a half hour. Dependent measures included carry time, weapon firing, fine-motor coordination, heart rate, oxygen uptake, perceived exertion, and subjective symptoms. Analysis of variance and post-hoc Newman-Keuls comparison of means revealed that men carried stretchers longer than women (p < 0.05). Harness use resulted in the stretcher being carried longer (23.1 ± 8.9 vs. 6.1 ± 5.9 min), at lower heart rates (141.9 ± 17.9 vs. 149.9 ± 14.7 beats per min), at slightly higher intensity , and with less fatigue in the forearm and hand (p < 0.05). Four-person teams maintained pre-carry fine-motor and marksmanship scores and carried longer (16.9 ± 11.0 vs. 12.3 ± 11.4 min), while working at a slightly lower intensity (), compared with two-person teams (p < 0.05). Use of four-person teams with a harness resulted in an 8-fold increase in carry time, compared with two-person hand-carry teams (24.5 ± 9.0 vs. 3.0 ± 1.8 min). Four-person teams with a shoulder harness are therefore recommended for prolonged carries.
Article
The results from nine separate studies reporting comparable static and dynamic muscle strength measurements between men and women have been reviewed. The statistical data from these studies are presented in graphical and tabular form illustrating, when appropriate, the mean ± 1 S.D., and the mean percentage difference between men and women for the given measurement. The following differences in strength measurements were observed: upper extremity strength measurements in women were found to range from 35 to 79% of men's, averaging 55.8%; lower extremity strength measurements in women ranged from 57 to 86% of men's, averaging 71.9%; trunk strength for women ranged from 37 to 70% of men's averaging 63.8%; and dynamic strength indicators revealed that women were from 59 to 84% as strong as men, with an average of 68.6%. In view of the wide range of mean percentage differences in muscle strength measurements between men and women, the author stresses the importance of exercising extreme care in making extrapolations from such data and recommends a method for making such extrapolations when the absence of direct measurements makes this necessary.
A group of 5 women and 11 men walked on a treadmill, each carrying a weight in the right hand. In separate experiments, the mass was varied to give total exhaustion within 3 min, 5 min, 9 min, and 13 min. In additional experiments 50% and 25% of the masses leading to exhaustion after 5 min were used, and these were stopped after 16 min. Heart rate (f c) and systolic blood pressure (BPs) were measured noninvasively. There was a consistent increase in (f c) x BPs during the experiments leading to exhaustion, while steady-states were obtained in the nonexhausting trials. An electromyogram (EMG) was recorded with cutaneous electrodes over the flexor carpi ulnaris and flexor digitorum superficialis muscles and the number of zero crossings (ZC) of the EMG signal per time unit were analysed. As the subjects approached exhaustion, the number of ZC declined exponentially, reaching approximately 50% of their initial values. In the nonexhausting experiments, however, the decline was slower and less marked, and during the second half of the experiment the number of ZC increased again. Subjectively, endurance was underestimated by all the subjects. It was concluded that cardiovascular and muscle criteria of fatigue in carrying coincided. Prolonged carrying in one hand of more than 6 kg or 10 kg for young healthy women and men respectively should not be recommended, since it could lead to cardiovascular non steady-states and EMG signs of fatigue.
Article
The decline of strength with age has often been attributed to declining muscle mass in older subjects. To investigate factors which might influence changes in strength across the life span, grip strength and muscle mass (as estimated by creatinine excretion and forearm circumference) were measured in 847 healthy volunteers, aged 20—100 years, from the baltimore longitudinal study of aging. Cross-sectional and longitudinal results concur that grip strength increases into the thirties and declines at an accelerating rate after age 40. However, the grip strength of 48% of subjects less than 40 years old, 29% of individuals 40–59 years old, and 15% of subjects older than 60 did not decline during the average 9-year follow-up. Grip strength is strongly correlated with muscle mass (r2 = .60, p < .0001). However, using multiple regression analysis, grip strength is more strongly correlated with age (partial r2 = .38) than muscle mass (partial r2 = .16). Additionally, a residuals analysis demonstrates that younger subjects are stronger and older subjects are weaker than one would predict based on their muscular size. Thus, while strength losses are partially explained by declining muscle mass, there remain other yet undetermined factors beyond declining muscle mass to explain some of the loss of strength seen with aging
Article
1. Skinfold thicknesses at four sites – biceps, triceps, subscapular and supra-iliac – and total body density (by underwater weighing) were measured on 209 males and 272 females aged from 16 to 72 years. The fat content varied from 5 to 50% of body-weight in the men and from 10 to 61% in the women.2. When the results were plotted it was found necessary to use the logarithm of skinfold measurements in order to achieve a linear relationship with body density.3. Linear regression equations were calculated for the estimation of body density, and hence body fat, using single skinfolds and all possible sums of two or more skinfolds. Separate equations for the different age-groupings are given. A table is derived where percentage body fat can be read off corresponding to differing values for the total of the four standard skinfolds. This table is subdivided for sex and for age.4. The possible reasons for the altered position of the regression lines with sex and age, and the validation of the use of body density measurements, are discussed.