Health guides & articles
In-depth explainers, head-to-head comparisons, and actionable how-to guides on every measurement we cover. Each guide reviews the research, explains what your numbers mean, and shows how to improve.
Comparative analyses
Head-to-head comparisons of health metrics — which one matters more, and when to use each.
BMI vs Body Roundness Index (BRI)
Which better predicts health risk? Zhang 2024 JAMA study, head-to-head comparison, and what each metric misses.
Grip Strength vs Walking Speed
The two strongest functional biomarkers compared. Which predicts longevity better — and why tracking both is smarter.
Waist-to-Height Ratio vs BMI
Why "waist less than half your height" outperforms BMI. Ashwell 2012 meta-analysis, INTERHEART, and the biology of belly fat.
How-to guides
Actionable, research-backed guides to improve each health metric. Training plans, diet strategies, and expected timelines.
How to Improve Your Grip Strength
Dead hangs, farmer carries, plate pinches — with training plans for beginner through advanced. Expected results in 4-12 weeks.
How to Reduce Waist Circumference
Science-backed diet, exercise, and lifestyle strategies that actually shrink your waist. HIIT, fiber, sleep, and stress management.
How to Lower Your Resting Heart Rate
Aerobic exercise, sleep, hydration, and what to cut out. Timeline: 2-5 bpm in 4-8 weeks, 5-10 bpm in 3-6 months.
How to Improve Your Walking Speed
Step-ups, calf raises, balance drills, and interval walking. Training plans for every level — from slow walkers to maintenance.
How to Increase Lean Body Mass
Protein targets, progressive overload, recovery, and the Boer formula. Build muscle at any age — research shows it is never too late.
In-depth explainers
Comprehensive overviews of each measurement domain. What the research says, NHANES norms, and what your numbers mean.
The Complete US Health Norms Guide
A central hub linking all 12 measurements together. Where do you rank?
Grip Strength and Upper Body Strength
A longevity biomarker. Leong 2015 meta-analysis, NHANES norms, training strategies.
Waist, Hip, Arm, and WHR
WHO cutoffs, INTERHEART, body girth as visceral fat proxy.
Resting Heart Rate & Cardiac Health
Lower is better. NHANES RHR by age, mortality risk, fitness training effects.
Walking Speed & Longevity
Studenski 2011 JAMA, Bohannon 2008 meta-analysis, fall risk for older adults.
BMI, BRI, and Body Shape Indices
Why BMI is incomplete. 2024 JAMA BRI validation. Body shape vs. body weight.
Lean Body Mass & Body Composition
Boer formula, sarcopenia, resistance training to build muscle.
Not sure where to start?
Try a calculator first — get your percentile, then read the guide that matches your result.