Fig 5. HTW dimensions (start, distance, slowdown) for male and female runners by age range and ability.
HTW Start refers to the average distance at which runners begin the slowdown that corresponds to their hitting the wall. HTW Distance refers to the length of this slowdown and HTW Slowdown refers to the degree of this slowdown, relative to their base-pace (that is, their average pace during the 5–20km portion of the marathon).