Commentary on “International norms for adult handgrip strength: A systematic review of data on 2.4 million adults aged 20 to 100+ years from 69 countries and regions”

In the December 2025 issue of the Journal of Sport and Health Science, Tomkinson et al.¹ present international norms for adult handgrip strength (HGS) developed from a systematic review of 100 studies with 2.4 million adults aged 20 to 100+ years from 69 countries and regions. Twenty-eight international handGRIP Strength (iGRIPS) researchers contributed to the study. Their rationale for the study was the need for international age- and sex-specific norms for absolute (kilogram, kg) and normalized for standing height (meter, m) (kg/m²) HGS across the adult lifespan. The international norms provide a standard metric to present percentiles of absolute and normalized HGS values in men and women by 5-year age increments. HGS values peaked between ages 30–39, with peak absolute HGS at 49.7 kg in males and 29.7 kg in women. HGS values were similar in early adulthood (from 20 to 39 years) and declined per decade by –5.6 kg in males and –3.5 kg in females. The highest variability in HGS values was observed in later life (coefficient of variation not shown), with larger variability in females than males. As noted by the authors, the HGS norms help support global peer comparisons of HGS, inform clinicians of patients with low HGS strength that may place them at risk for adverse health outcomes, and provide utility for national and global surveillance activities that measure HGS.

It is well established that low muscle strength is an independent risk factor for morbidity^2,3 and mortality^2,4 and is predictive of falls⁵ and independent living in older populations.⁶ HGS is an easy and inexpensive measure of bodily muscle strength that has been measured in epidemiological⁷ and experimental⁸ studies, clinical settings,⁹ and diverse populations to identify global variation in HGS,¹⁰ associations between HGS and physical activity,¹¹ health-related fitness measures,¹² and health outcomes,2, 3, 4^,6 and to create country-specific HGS norms.^1,13 Of particular concern is the risk of low HGS on falls and hip fracture risks leading to disability in older adults. In a study of falls and hip fractures in 10,092 middle-aged males and females aged 60 to 80 enrolled in the China Health and Retirement Study (CHARLS), Guo et al.⁵ reported an inverse, dose–response relationship between quintiles (Q) of low (Q1 ≤ 23.0 kg) to high (Q5 ≥ 40.5 kg) HGS and incidence of falls (Q1 to Q5, adjusted odds ratio (aOR): 1.00–0.62, p < 0.001) and hip fractures (Q1 to Q5, aOR: 1.00–0.46, p < 0.009). Each 1 kg increase in grip strength was associated with a 4% lower risk of hip fractures. Pham et al.¹⁴ reported fall risks in 16,445 community-based older Australian and American adults aged ≥ 65 enrolled in the Aspirin in Reducing Events in the Elderly (ASPREE)-Fracture substudy. The lowest HGS quintile (Q1, HGS≤ 24.7 kg in males, HGS ≤ 14.0 kg in females) had a 73% increased risk of falls compared to older adults in the highest quintile (Q5, HGS≥ 35.0 kg in males, HGS ≥ 20.7 kg in females) (hazard ratio (HR) = 1.73, 95% confidence interval (95%CI): 1.42–2.10).

Tomkinson et al.¹ observed declines in absolute HGS by sex for each year of life. This observation is consistent with other studies that report decreases in HGS with increased age.^10,13 The second version of the European Working Group on Sarcopenia in Older People (EWGSOP2)¹⁵ lists HGS values of <27 kg in males and <16 kg in females as sarcopenia criteria, and the Sarcopenia Definition and Outcomes Consortium¹⁶ lists HGS values of <35.5 kg in males and <20.0 kg in females. This range of HGS values is consistent with studies showing associations between HGS, morbidity, and mortality risks^5,6,14,17 and places adults with low HGS in the 10th to 20th percentiles of the norms presented by Tomkinson et al.¹

The associations between low HGS and adverse health outcomes highlight the importance of engaging in lifespan physical activities (PAs) that require increased grip strength. Leisure-time PAs (e.g., racket sports, golf, weight training, and gardening) and home maintenance tasks (e.g., carrying grocery bags, house cleaning, sweeping, and shoveling) that require gripping and lifting moderately heavy objects can help to prevent declines in HGS that accompany aging.^18,19 Furthermore, one is never too old to start a muscle-strengthening program to increase HGS. A sample of 17 Chinese sarcopenic women aged 65–75 increased their HGS from 17.24 ± 4.63 kg to 21.95 ± 4.71 kg (mean ± SD; p < 0.05) following an 8-week kettlebell exercise training program.²⁰ The results contrast the no-exercise control group, which showed no changes in HGS (p > 0.05).²⁰ The exercise group’s HGS scores increased from ∼ 10th to ∼30th percentiles in Tomkinson et al.’s¹ rankings, reducing their risks for sarcopenia diagnosis and poor health outcomes.

Practitioners should be informed that the differences in the types of handgrip dynamometers used to measure HGS can affect the accuracy of maximal HGS. The Jamar hydraulic dynamometer is widely recognized as the gold standard in clinical and research settings,^21,22 owing to its robust reliability and foundational role in developing normative reference data. In contrast, the K-Force Grip—a lighter, Bluetooth-enabled, cylindrical digital device—has been increasingly adopted due to its portability and digital interface, particularly among older adults and in remote rehabilitation contexts.21, 22, 23 However, studies found that although the K-Force demonstrates excellent reliability and strong correlations with Jamar (r ≥ 0.89, intraclass correlation coefficient (ICC) > 0.90),^22,24 it systematically underestimates HGS by 4.5–8.5 kg.22, 23, 24 These discrepancies are attributed to differences in handle design, device dimensions, and mechanical resistance. These factors have important implications for the clinical interpretation of grip strength values and their comparability to established thresholds.

Tomkinson et al.¹ addressed inconsistencies across handgrip dynamometers and protocols by applying adjustment factors derived from over 366,000 raw data points, harmonizing diverse datasets to a standardized reference protocol based on the Southampton method. This process enabled them to produce international normative percentiles for over 2.4 million adults from 69 countries. However, not all device- or protocol-related biases may be fully correctable, especially when original studies lack detailed reporting. While harmonization improves data comparability, the consistent underestimation seen with the K-Force Grip suggests it should not be used interchangeably with the Jamar for diagnostic decisions or normative comparisons. Standardization in device use and testing protocols remains essential for valid HGS assessment.

Overall, the international HGS norms presented by Tomkinson et al.¹ provide researchers and practitioners with a valuable resource to evaluate absolute and relative HGS in men and women across the lifespan. The norms can identify risks for falls, loss of independent living, morbidity, and mortality. However, researchers and practitioners should be aware of the strengths and limitations of handgrip dynamometers to avoid inaccurate HGS measures.

Authors’ contributions

BEA conceived the commentary and drafted and edited the manuscript; ZZ helped draft and edit it. Both authors have read and approved the final version of the manuscript, and agree with the authors’ order of presentation.

Competing interests

Both authors declare that they have no competing interests.