Reference for Shevuot 33:6

בעי רבא שהיות מהו שיצטרפו ותיפשוט ליה מדידיה התם בדלא שהה

It remains undecided. IF HE WENT OUT THE LONGER WAY, HE IS LIABLE; THE SHORTER WAY, HE IS EXEMPT, etc. Raba said: THE SHORTER WAY which they said [exempts him, implies] even [walking] heel to toe,<span class="x" onmousemove="('comment',' Taking very short steps, so that the toe of one foot touches the heel of the foot in front.');">⁸</span> and even the whole day.

Jastrow