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Handgrip strength (HS) significantly influences quality of life and is a critical determinant of overall human health (1). Research has established that low HS is linked with heightened risks of all-cause mortality and cardiovascular disease (2). This study draws on data from the 2020 Chinese National Survey on Adults’ Fitness, the most comprehensive nationally representative survey in China. HS measurements were conducted using the Jianmin II device (Beijing Municipality, China). Findings from 2020 show that the mean HS among Chinese adults was 32.8 kg with a standard deviation of 13.2 kg, representing a decrease of 3.1 kg from 2000 (3). Additionally, the low muscle strength rate (LMSR) markedly increases with age; individuals aged 75 to 79 have an LMSR 13.7 times higher than those aged 20 to 24. Investigating the current condition of HS and LMSR among Chinese adults holds significant public health importance, as it aids in devising strategies to prevent or delay the decline in muscle strength, thereby reducing disease burden and enhancing population health.
This study adopted a complex, stratified multistage probability cluster sampling design detailed in previous reports (4), with further elaboration provided in
Supplementary Material . It then adjusted the 2020 survey data weighting based on gender and age distributions in 5-year increments as per the 7th National Population Census, reported by the National Bureau of Statistics in 2020, covering 31 provincial-level administrative divisions (PLADs). For measuring HS, this study employed a Jianmin II HS measurement device (Beijing, China) to assess the maximal HS in the dominant hand. Prior to testing, participants adjusted the grip width to an appropriate force with their dominant hand, stood upright with feet apart at shoulder width, and arms naturally positioned, inclining 10–30° from the trunk. The maximal HS value was recorded after three consecutive tests (in kg, rounded to the nearest 0.1 kg), ensuring a minimum rest interval of two minutes between tests. Low muscle strength (LMS) was classified following the Asian Working Group for Sarcopenia (AWGS) guidelines, diagnosing males with HS under 26 kg and females under 18 kg as LMS. This study calculated the LMSR for 2020 using a weighted logistic regression model, with diagnostic status as the outcome. The prevalence odds ratio (POR) was determined by gender and by comparing urban versus rural residency, using males and urban residents as reference categories. Two POR models were applied: a crude model leveraging only sampling weights and an adjusted model that included additional covariates such as urban or rural residence, minority status, education level, occupation, economic level by PLADs, along with sampling weights (Supplementary Table S1 ). Outliers in the HS and weight data that exceeded 1.5 times the interquartile range were excluded as per Tukey’s method. In 2020, out of 158,720 potential participants aged 20 to 79 contacted, 128,759 agreed to participate, resulting in a response rate of 81.1%. Non-responders — those who refused to participate, did not respond, were physically or mentally unable to participate, did not reside at their registered address, or provided three or more missing or implausible responses in the questionnaire — were excluded from the analysis (5) (Supplementary Figure S1 ). The name of sampling cities (districts and counties) inSupplementary Table S2 . The study’s protocol involving human participants was ethically approved by the General Administration of the Sports of China, with informed consent obtained from all participants. Kernel density estimation was employed for the density map (Table 1). Statistical significance was set at a two-sided P value of less than 0.05. All statistical analyses were conducted using R software (version 4.1.1; R Foundation for Statistical Computing, Vienna, Austria), with results reported as odds ratios (ORs) for dichotomous outcomes and associated 95% confidence intervals (CI).Items Handgrip strength, Mean (SD), kg Low muscle strength rate, % (95% CI) Total (n=128,759) 32.8 (13.2) 9.0 (8.8, 9.1) Sex Male (n=64,679) 40.4 (8.7) 8.1 (7.9, 8.3) Female (n=64,080) 25.1 (5.4) 9.1 (8.8, 9.3) Rural and Urban Rural (n=68,598) 31.7 (10.6) 11.6 (11.4, 11.9) Urban (n=60,161) 34.0 (10.9) 5.3 (5.1, 5.5) Age group 20–24 (n=10,159) 35.1 (9.3) 2.7 (2.4, 3.0) 25–29 (n=10,738) 35.5 (10.6) 2.9 (2.6, 3.2) 30–34 (n=11,016) 35.9 (12.0) 2.5 (2.2, 2.8) 35–39 (n=10,599) 35.6 (10.5) 2.5 (2.2, 2.8) 40–44 (n=10,740) 35.4 (10.1) 2.9 (2.6, 3.3) 45–49 (n=10,779) 34.9 (10.9) 3.0 (2.7, 3.4) 50–54 (n=10,186) 33.9 (11.0) 3.8 (3.5, 4.2) 55–59 (n=9,696) 33.1 (9.8) 5.0 (4.6, 5.5) 60–64 (n=11,426) 29.7 (9.6) 12.8 (12.1, 13.4) 65–69 (n=11,476) 28.3 (9.1) 17.2 (16.5, 17.9) 70–74 (n=11,258) 26.4 (7.1) 28.7 (27.8, 29.6) 75–79 (n=10,686) 24.9 (5.8) 37.1 (36.1, 38.1) Abbreviation: SD=standard deviation; CI=confidence interval. Table 1. Basic data on handgrip strength and the low muscle strength rate in China, 2020.
For HS as shown in Table 1, the average HS in males is significantly higher than in females (P<0.001). In 2020, HS in the 20–24 age group was noted to decrease by 10.2 kg, from 35.1 kg to 24.9 kg in those aged 75–79. The peak HS occurs between ages 30–34. Additionally, urban residents have a mean HS that is 2.3 kg greater than that of rural residents (P<0.001). Figure 1 depicts the distribution of HS across various demographics. For the LMSR, data presented in Tables 1 and 2 indicate similarities with the HS findings. Using the male LMSR data as a benchmark, the adjusted model reveals that the OR for females is 0.96 (95% CI: 0.92, 1.00), suggesting that males are more likely to have higher LMSR than females. Among Chinese adults, those in the 75–79 age group exhibit the highest LMSR, being 13.4 times greater than those in the 20–24 age group, according to the adjusted model. Furthermore, there is a pronounced increase in LMSR after the age of 60.
Figure 1.Handgrip strength distributions across various groups in China, 2020.
(A) Handgrip strength distribution; (B) Handgrip strength distribution of different sex; (C)Handgrip strength distribution between rural and urban areas; (D) Handgrip strength distribution between different age groups.Items Crude model POR (95% CI) Adjusted model POR (95% CI) Sex Male (n=64, 679) Ref. Ref. Female (n=64, 080) 1.13 (1.09, 1.17) 0.96 (0.92, 1.00) Rural and urban Rural (n=68, 598) Ref. Ref. Urban (n=60, 161) 2.35 (2.25, 2.45) 1.16 (1.10, 1.22) Age, years 20–24 (n=10, 159) Ref. Ref. 25–29 (n=10, 738) 1.08 (0.91, 1.28) 1.11 (0.93, 1.32) 30–34 (n=11, 016) 0.93 (0.78, 1.11) 0.96 (0.81, 1.15) 35–39 (n=10, 599) 0.92 (0.77, 1.10) 0.94 (0.79, 1.13) 40–44 (n=10, 740) 1.10 (0.92, 1.30) 1.06 (0.89, 1.26) 45–49 (n=10, 779) 1.13 (0.95, 1.34) 1.05 (0.89, 1.26) 50–54 (n=10, 186) 1.44 (1.23, 1.70) 1.34 (1.13, 1.58) 55–59 (n=9, 696) 1.93 (1.65, 2.26) 1.80 (1.53, 2. 12) 60–64 (n=11, 426) 5.33 (4.65, 6.12) 4.91 (4.23, 5.23) 65–69 (n=11, 476) 7.55 (6.59, 8.65) 6.65 (5.73, 7.72) 70–74 (n=11, 258) 14.61 (12.79, 16.70) 12.62 (10.90, 14.63) 75–79 (n=10, 686) 21.42 (18.75, 24.47) 18.44 (15.91, 21.37) Note: Crude model: only sampling weights are considered; adjusted model: based on the sample population, urban and rural areas, ethnic groups, occupations, educational levels, economic conditions in the PLADs.
Abbreviation: CI=confidence interval; POR=prevalence odds ratio; PLAD=provincial-level administrative division; Ref.=reference group.Table 2. Analysis of the POR of low muscle strength rate among various groups of Chinese adults in 2020.
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Utilizing the latest nationally representative data, this research explored HS levels and LMSR among Chinese adults. The findings revealed that Chinese males exhibited significantly higher HS levels (40.4 kg) compared to Chinese females (25.1 kg). Additionally, a decline in HS was observed at an earlier age among Chinese adults, with the peak HS reached between the ages of 30–34, followed by a gradual decrease with advancing age. Moreover, adults living in urban areas showed higher HS levels and lower LMSR compared to their rural counterparts.
HS varies significantly between China and other countries. In a 2015 prospective urban epidemiological study, HS was assessed among 125,462 adults aged 35–70 years from diverse regions globally. The highest median HS levels were observed in Europe and North America at 30.0 kg (25%–75th percentile: 26.0–35.0 kg) (6). In contrast, the average HS in China was reported as 32.8 kg with a standard deviation of 13.2 kg. Furthermore, a Brazilian study indicated that the HS for males and females aged over 20 years was 42.8±0.4 kg and 25.4±0.3 kg, respectively (7). Such discrepancies in HS can be attributed to various factors including social and economic conditions, environmental influences, methods of HS measurement, sampling conditions, and behavioral habits. Therefore, regional HS assessments should be considered as primarily reference values. Trends in HS levels across different regions suggest significant changes. From 2000 to 2017, data revealed a declining trend in several countries: China showed a percent decrease per decade of −4.0 (95% CI: −4.3, −3.7), Japan −0.6 (−0.9, −0.3), England −6.3 (−7.2, −5.4), Western Europe −2.3 (−3.0, −1.6), Canada −4.7 (−5.3, −4.1), and the USA −1.5 (−2.3, −0.7). Conversely, Northern Europe and Southern Europe exhibited growing trends at rates of 3.3 (2.8, 3.8) and 7.0 (6.1, 7.9), respectively (8). Despite improvements in quality of life, health status as measured by HS is not improving in most regions. Predominantly, HS research has been concentrated in high-income countries, with a paucity of data from low and middle-income nations. Future studies should focus on contemporary HS levels, and explore interventions and cohort studies to enhance HS. Resistance training and scientifically informed nutritional intake have been demonstrated to effectively boost HS and muscle mass. Important nutritional factors include protein, vitamin D, omega-3 fatty acids, magnesium, adherence to a Mediterranean diet, and increased consumption of fruits and vegetables (9–10). It is advisable for China to promote resistance training and these nutritional practices, especially among women, to improve HS.
Exercise remains the cornerstone of sarcopenia management. The study indicated an age-related escalation in the LMSR among Chinese adults. Specifically, the LMSR in individuals aged 55–59 was approximately 7.4 times higher than in those aged 75–79. Additionally, females demonstrated a significantly higher risk than males. The European Working Group on Sarcopenia in Older People has previously highlighted the prevalence of sarcopenia in the elderly, noting its strong correlation with both disability and mortality (11). Thus, it is vital to focus on enhancing muscle mass and strength, especially in older women, to improve their quality of life.
HS often manifests as an external indicator of various skeletal muscle system diseases (12). HS is recognized as an indicator of healthy aging (13). Research has shown that HS has a stronger association with overall mortality and cardiovascular disease mortality than either systolic blood pressure or total physical activity levels (2). Musculoskeletal disorders are increasingly recognized as major public health challenges, impacting the burden of disease and overall health status. According to the World Health Organization (WHO) in 2019, the disability-adjusted life years (DALYs) attributable to musculoskeletal disorders saw a 65.74% increase from 1990 to 2017, highlighting its significance as a global health issue (14). Consequently, it is essential to explore preventative strategies against muscle weakness in adults, underlining the need for extensive research on muscle strength.
The strength of this study is derived from its use of contemporary data collected from all 31 PLADs, municipalities, and districts across China, which enhances its credibility.
However, it does present certain limitations that warrant attention. First, this study is a cross-sectional study, so we cannot explain causal relationship. Then, we collected covariates using a self-reported questionnaire, which might have led to recall bias. Specifically, the classification of LMSR is overly simplistic and would benefit from a more nuanced categorization into mild, moderate, and severe levels to facilitate more effective intervention strategies.
In conclusion, this study provides an up-to-date assessment of the prevalence of HS and LMSR across China as of 2020, on a national and population-based scale. Consequently, it is recommended that further policies be developed to improve HS and skeletal muscle levels among women, the elderly, and rural communities.
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No conflicts of interest.
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