In a nationwide DXA-based cross-sectional study of Korean adults, both relative muscle mass (ASM/BW) and relative handgrip strength were independently and inversely associated with metabolic syndrome, with the highest odds of MetS observed when both indicators were concurrently low.
Key Findings
Results
Relative muscle mass (ASM/BW) was independently and inversely associated with metabolic syndrome in both men and women after full adjustment.
In men, OR for MetS per unit increase in ASM/BW was 0.79 (95% CI 0.73–0.86)
In women, OR for MetS per unit increase in ASM/BW was 0.86 (95% CI 0.80–0.92)
Both associations were estimated with both indicators entered simultaneously in a fully adjusted joint model
The analysis used complex-sample logistic regression accounting for the survey design of KNHANES
Results
Relative handgrip strength (HGS/body weight) was independently and inversely associated with metabolic syndrome in both men and women.
In men, OR for MetS per unit increase in relative HGS was 0.98 (95% CI 0.96–0.99)
In women, OR for MetS per unit increase in relative HGS was 0.97 (95% CI 0.95–0.98)
The association was estimated simultaneously with ASM/BW in the fully adjusted model, indicating independent contributions of each measure
The relative HGS association was attenuated when MetS was defined without the waist circumference criterion
Results
Concurrently low muscle mass and low grip strength were associated with the highest odds of metabolic syndrome compared to having high levels of both.
Men with both low ASM/BW and low relative HGS had an OR of 3.04 for MetS
Women with both low ASM/BW and low relative HGS had an OR of 2.42 for MetS
Participants were classified into four groups using sex-specific medians of both indicators
These joint-exposure findings suggest a complementary relationship between muscle mass and muscle strength in relation to MetS risk
Results
The ASM/BW association with metabolic syndrome was more robust across sensitivity analyses than the relative HGS association.
The ASM/BW association persisted when MetS was defined without the waist circumference criterion
The relative HGS association was attenuated under the same waist-criterion-excluded MetS definition
ASM/BMI showed similar inverse associations to ASM/BW, whereas ASM/Ht² showed a different pattern
The authors note that 'associations differed by normalization method, the optimal choice of which remains uncertain'
Methods
The study analyzed 3,033 Korean adults aged 40 years and older using concurrent DXA-based appendicular skeletal muscle mass and handgrip strength measurements from the 2024 KNHANES.
Data source was the 2024 Korea National Health and Nutrition Examination Survey (KNHANES)
Muscle mass was assessed as appendicular skeletal muscle mass (ASM) by dual-energy X-ray absorptiometry (DXA)
Primary muscle mass indicator was ASM normalized to body weight (ASM/BW); primary strength indicator was HGS normalized to body weight (relative HGS)
The cross-sectional design means findings 'indicate association only and require prospective validation before clinical application'
What This Means
This research suggests that having lower muscle mass relative to body weight and lower grip strength relative to body weight are each independently linked to a higher likelihood of having metabolic syndrome — a cluster of conditions including high blood pressure, high blood sugar, excess belly fat, and abnormal cholesterol levels that raise the risk of heart disease and diabetes. The study looked at over 3,000 Korean adults aged 40 and older, using precise body composition scans (DXA) to measure muscle mass and grip strength tests to measure muscle strength. Importantly, both measures appeared to contribute separately to metabolic syndrome risk, meaning they are capturing different aspects of muscle health.
The most striking finding was that adults who had both low muscle mass and low grip strength at the same time had roughly 2.4 to 3 times the odds of having metabolic syndrome compared to those with high levels of both. This suggests the two measures — how much muscle a person has and how strong that muscle is — may work together in affecting metabolic health, and that looking at only one of them might miss part of the picture. Relative muscle mass (adjusted for body weight) appeared to have a more consistent relationship with metabolic syndrome across different ways of measuring and defining it, while the grip strength association was somewhat weaker when belly fat was removed from the metabolic syndrome definition.
This research is based on a snapshot in time (cross-sectional design), so it cannot prove that low muscle mass or low grip strength causes metabolic syndrome — it only shows they tend to occur together. The authors emphasize that these findings need to be confirmed in studies that follow people over time before they can be used to guide clinical decisions. Nevertheless, the results point to the potential value of assessing both muscle quantity and muscle strength as complementary indicators of metabolic health in middle-aged and older adults.
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Lee E, Kim H. (2026). Relative muscle mass and grip strength as complementary correlates of metabolic syndrome: a nationwide DXA-based study of Korean adults.. Endocrine. https://doi.org/10.1007/s12020-026-04804-3