Mechanically powered shorts

From These bionic shorts help turn an epic hike into a leisurely stroll on MIT Technology Review:

The new “exosuit” is made of soft materials that attach around the waist and thighs and an actuator that attaches to the lower back. Its function is controlled by an algorithm that detects the transition from walking to running, motions that are significantly different and require different actuation.

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The powered pants, which weigh 5 kilograms (11 pounds), reduce a person’s metabolic work rate 9.3% when walking and 4% when running (equivalent to removing 12 to 17 pounds from the waist).