Table 5– Reference equations for predicting the 6-min walking distance (6MWD) in healthy individuals
 First author [ref.] Sex Reference equation r2 Casanova [173] Males 6MWD=361-(age×4)+(height×2)+(3×HRmax/HRmax%pred)-(weight×1.5) 0.09–0.73# Females 6MWD=361-(age×4)+(height×2)+(3×HRmax/HRmax%pred)-(weight×1.5)-30 0.09–0.73# Dourado [174] Both 6MWD=299.296-(2.728×age)-(2.160×weight)+(361.731×height¶)+(56.386×sex§) 0.54 Both 6MWD=109.764-(1.794×age)-(2.383×weight)+(423.110×height¶)+(2.422×grip strength) 0.54 Hill [175] Both 6MWD=970.7+(-5.5×age)+(56.3×sex§) Soares [176] Both 6MWD=511+(height2×0.0066)-(age2×0.030)-(BMI2×0.068) Osses [177] Males 6MWD=530-(3.31×age)+(2.36×height)-(1.49×weight) 0.55 Females 6MWD=457-(3.46×age)+(2.61×height)-(1.57×weight) 0.63 Alameri [178] Both 6MWD=(2.81×height)+(0.79×age)-28.5 0.25 Ben Saad [179] Both 6MWD=720.50-(160×sexƒ)-(5.14×age)-(2.23×weight)+(2.72×height) 0.77 Iwama [180] Both 6MWD=622.461-(1.846×age)+(61.503×sex§) 0.30 Jenkins [181] Males 6MWD=867-(5.71×age)+(1.03×height) Females 6MWD=525-(2.86×age)+(2.71×height)-(6.22×BMI) Masmoudi [182] Both 6MWD=299.8-(4.43×age)+(342.6×height¶)-(1.46×weight)+(62.5×sexƒ) 0.60 Camarri [183] Both 6MWD=64.69+(3.12×height)+(23.29×FEV1) 0.43 Both 6MWD=216.90+(4.12×height)-(1.75×age)-(1.15×weight)-(34.04×sexƒ) 0.36 Chetta [184] Both 6MWD=518.853+(1.25×height)-(2.816×age)-(39.07×sexƒ) 0.42 Poh [185] Both 6MWD=(5.50×HRmax/HRmax%pred)+(6.94×height)-(4.49×age)-(3.51×weight)-473.27 0.78 Gibbons [186] Both 6MWD=868.8-(age×2.99)-(sexƒ×74.7) 0.41 Enright [187] Males 6MWD=510+(2.2×height)-(0.93×weight)-(5.3×age) 0.20 Females 6MWD=493+(2.2×height)-(0.93×weight)-(5.3×age) 0.20 Troosters [188] Both 6MWD=218+(5.14×height)-(5.32×age)-(1.80×weight)+(51.31×sex§) 0.66 Enright [189] Males 6MWD=(7.57×height)-(5.02×age)-(1.76×weight)-309 0.42 Females 6MWD=(2.11×height)-(2.29×weight)-(5.78×age)+667 0.38 Males 6MWD=1.140-(5.61×BMI)-(6.94×age) Females 6MWD=1.017-(6.24×BMI)-(5.83×age)
• Units are as follows, unless otherwise stated. 6MWD: m; age: years; height: cm; weight: kg; grip strength: kg; body mass index (BMI): kg·m−2; forced expiratory volume in 1 s (FEV1): L. HRmax/HRmax%pred: maximum heart rate during the 6-min walk test divided by the predicted maximum heart rate. #: adjusted r2 values for males and females; : in m; §: males=1, females=0; ƒ: males=0, females=1.