To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Play VideoPlayMuteCurrent Time 0:00/Duration Time 0:00Loaded: 0%Progress: 0%Stream TypeLIVERemaining Time -0:00 Playback Rate1ChaptersChaptersdescriptions off, selectedDescriptionssubtitles off, selectedSubtitlescaptions off, selectedCaptionsAudio TrackFullscreenThis is a modal window. Captions Settings Dialog Beginning of dialog window. Escape will cancel and close the window. Text Color White Black Red Green Blue Yellow Magenta Cyan Transparency Opaque Semi-Opaque Background Color Black White Red Green Blue Yellow Magenta Cyan Transparency Opaque Semi-Transparent Transparent Window Color Black White Red Green Blue Yellow Magenta Cyan Transparency Transparent Semi-Transparent Opaque Font Size 50% 75% 100% 125% 150% 175% 200% 300% 400% Text Edge Style None Raised Depressed Uniform Dropshadow Font Family Proportional Sans-Serif Monospace Sans-Serif Proportional Serif Monospace Serif Casual Script Small Caps Defaults Done Movie 1 Example of a subject walking on part of the trail (approximately the second half of the trail). Preferred walking speed on rough terrain: is it all about energetics? Koren Gast, Rodger Kram, and Raziel Riemer Journal of Experimental Biology 2019. 222:None-None; doi: 10.1242/jeb.185447 Download Original Video