Research

Mixed

Multi-frequency bioelectrical impedance analysis (MF-BIA) using an age-independent equation (incorporating impedance ratios and 1/Z50) accurately estimates appendicular skeletal muscle mass (ALM) comparable to DXA, whereas traditional age-dependent BIA equations significantly underestimate ALM in younger adults.

If you are tracking muscle mass changes, especially if you are young or comparing yourself to older data, standard consumer BIA scales may be misleading because they often use age-dependent formulas that underestimate muscle in younger people. For accurate research or clinical assessment, use a validated, age-independent MF-BIA equation or DXA. For general fitness, focus on strength and performance metrics rather than the absolute number from a consumer scale.

GoodQualifiesHIGH confidence
The residual was significantly correlated with age, which indicated that the previous BIA equation underestimated ALM in young adults. The previous equation cannot be used to examine age-related ALM loss.
Yosuke Yamada et al. · International Journal of Environmental Research and Public Health · 2017

Why this rating

Large sample size (n=756 for development, n=233 for validation, n=2992 for cutoffs), rigorous statistical validation (R2 > 0.85), and comparison against gold-standard DXA.

Source

Developing and Validating an Age-Independent Equation Using Multi-Frequency Bioelectrical Impedance Analysis for Estimation of Appendicular Skeletal Muscle Mass and Establishing a Cutoff for Sarcopenia

Yosuke Yamada et al. · International Journal of Environmental Research and Public Health · 2017

DOI 10.3390/ijerph14070809

cross_sectional · n=3846Cited 185×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →