Waist-to-hip ratio (WHR)

Waist-to-hip ratio (WHR) is waist circumference divided by hip circumference, used to assess fat distribution and identify clients with more abdominal fat.^{1Ozemek et al., ACSM’s Guidelines for Exercise Testing and Prescription, 12th ed., p. 181.} At equal weight, clients carrying more circumference at the waist face higher risks of hypertension, type 2 diabetes, hyperlipidemia and coronary artery disease than those carrying it on the extremities.^{2International Personal Trainer Academy, Certified Personal Trainer Textbook, p. 157.}

Health risk rises with WHR, and cutoffs vary by age and sex.^{1Ozemek et al., ACSM’s Guidelines for Exercise Testing and Prescription, 12th ed., p. 181.} ACSM classifies risk as very high above 0.95 for men and 0.86 for women under 60.^{1Ozemek et al., ACSM’s Guidelines for Exercise Testing and Prescription, 12th ed., p. 181.} For ages 60 to 69, that classification starts above 1.03 for men and 0.90 for women.^{1Ozemek et al., ACSM’s Guidelines for Exercise Testing and Prescription, 12th ed., p. 181.}

In practice

• Measure the waist at its smallest girth around the abdomen and the hips at the largest girth around the buttocks.^{3Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 224.} Keep the tape snug and horizontal without indenting the skin, then divide waist by hip.^{3Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 224.}
• Use the same client position at every measurement.^{3Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 224.} The NSCA notes that protocols differ on whether the arms hang relaxed.^{3Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 224.}
• The NSCA reports that waist circumference and WHR may predict atherosclerosis and cardiovascular risk better than BMI.^{4Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 533.} ACSM also reports that both outperform BMI for judging obesity-related risk, and that BMI and WHR correlate only weakly, providing different information.^{1Ozemek et al., ACSM’s Guidelines for Exercise Testing and Prescription, 12th ed., p. 181.}
• Waist circumference alone is also usable; ACSM treats it as a proxy for visceral and abdominal fat.^{1Ozemek et al., ACSM’s Guidelines for Exercise Testing and Prescription, 12th ed., p. 181.}