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

Abstract

Background: Muscular strength is a powerful marker of current health status and robust predictor of age-related disease and disability. Handgrip strength (HGS) using isometric dynamometry is a convenient, feasible, and widely used method of assessing muscular strength among people of all ages. While adult HGS norms have been published for many countries, no study has yet synthesized available data to produce international norms. The objective of this study was to generate international sex- and age-specific norms for absolute and body size-normalized HGS across the adult lifespan.

Methods: Systematic searches were conducted in 6 databases/web search engines (MEDLINE, SPORTDiscus, Embase, Web of Science, CINAHL, and Google Scholar) up to December 1, 2023. We included full-text peer-reviewed observational studies that reported normative HGS data for adults aged ≥20 years by sex and age. Pseudo data were generated using Monte Carlo simulation following harmonization for methodological variation. Population-weighted Generalized Additive Models for Location, Scale, and Shape were used to develop sex- and age-specific norms for absolute HGS (kg) and HGS normalized by height (Ht, m) squared (i.e., HGS/Ht² in kg/m²). Norms were tabulated as percentile values (5th to 95th) and visualized as smoothed percentile curves.

Results: We included data from 100 unique observational studies representing 2,405,863 adults (51.9% female) aged 20 to 100+ years from 69 countries and regions tested from the year 2000 onward. On average, absolute and normalized HGS values negligibly improved throughout early adulthood, peaked from age 30-39 years (at 49.7 kg (males) and 29.7 kg (females) for absolute HGS or 16.3 kg/m² (males) and 11.3 kg/m² (females) for HGS/Ht²), and declined afterwards. The age-related decline in HGS accelerated from middle to late adulthood and was slightly larger for males than for females during middle adulthood.

Conclusion: This study provides the world's largest and most geographically comprehensive international norms for adult HGS by sex and age. These norms have utility for global peer-comparisons, health screening, and surveillance.

Keywords: Adult; Hand strength; Mass screening; Population health; Reference values.

Graphical abstract

Fig. 1

PRISMA flow diagram showing the flow of studies through different phases of the systematic review. HGS = handgrip strength; PRISMA = Preferred Reporting Items for Systematic reviews and Meta-Analyses.

Fig. 2

Smoothed percentile curves (P₅ to P₉₅) for absolute handgrip strength in kilograms (kg) and normalized handgrip strength (handgrip strength in kg divided by height in meters squared (kg/m²)) for adults aged 20 to 100+ years. Smoothed percentile curves for absolute handgrip strength (top panels) and normalized handgrip strength (bottom panels) are shown separately for males (left panels) and females (right panels). Population-weighted smoothed percentiles were calculated using the Generalized Additive Model for Location, Scale, and Shape method. Percentiles were adjusted to the reference test and reporting protocol (i.e., dynamometer type = hydraulic, body position = seated, elbow position = flexed, radioulnar position = neutral, handle position = adjusted to hand size, testing hand = both, repetitions per hand = 3, and summary statistic = maximum). No statistical adjustment was made for shoulder or wrist position (see Supplementary Harmonization Methods for details). Large, high-resolution images for each panel are provided as Supplementary Fig. 2A–2D.

Fig. 3

Sex- and age-related differences in mean absolute handgrip strength and normalized handgrip strength for adults aged 20 to 100+ years. Sex-related (i.e., the standardized difference in absolute handgrip strength (top left panel) and normalized handgrip strength (top right panel) between males and females in 5-year age intervals) and age-related differences (i.e., the standardized difference in absolute handgrip strength (bottom left panel) and normalized handgrip strength (bottom right panel) with each 5-year age interval relative to age 20 years) with adjustment for test and reporting protocols are shown as standardized (Cohen's) effect sizes for absolute handgrip strength (left panels) and normalized handgrip strength (right panels). The limits of the gray zone represent a large, standardized effect size (i.e., 0.8 or –0.8). Positive sex-related differences indicate higher handgrip strength for males than for females (top panels). Age-related differences are standardized to age 20 years = 0. Positive age-related differences indicate higher handgrip strength for adults aged >20 years than for adults aged 20 years, and negative age-related differences indicate lower handgrip strength for adults aged >20 years than for adults aged 20 years (bottom panels).