Table 1 Mean ratings (SD) (Round 1; range: 0–10) and agreement rates (Round 2; %) for items to be included within the definition

Provisionally included

Low heel to toe drop

9.2 (1.8)

88.1

High flexibility

9.1 (1.8)

95.2

Absence of motion control/stability technologies

9.1 (1.9)

97.6

Provide minimal interference to the natural movement of the foot

9.0 (2.6)

88.1

Light weight

8.9 (1.9)

92.9

Low stack height

8.6 (2.3)

88.1

Allow for natural expansion of the forefoot

8.4 (2.6)

85.7

Anatomical last (wide toe-box)

7.3 (3.3)

78.6

Encourage lower limb kinematics similar to barefoot

7.2 (3.8)

61.9

Encourage lower limb kinetics similar to barefoot

7.1 (3.9)

61.9

Round 1

Round 2

Rating

Exclusion

Provisionally excluded

Allow for ground feel

6.9 (3.1)

66.7

Encourage lower limb muscle activation similar to barefoot

6.8 (3.9)

71.4

Absence of sole cushioning^a

5.6 (3.8)

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Facilitate afferent feedback similar to barefoot running^a

4.9 (3.8)

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Replicate energy expenditure of barefoot running

4.8 (3.5)

83.3

Replicate oxygen consumption of barefoot running

4.6 (3.4)

81.0

Adequate vertical volume of toe-box^a

3.8 (3.5)

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