Scientists have built a light-weight wearable boot-like exoskeleton which reduces the energy needed for walking.
Researchers say the exoskeleton gives a 7% gain without chemical or electrical energy.
According to research published in the journal Nature, the energy saving is relatively modest but represents a considerable improvement on past designs.
Engineers have been trying to create machines since at least the 1890s to make walking easier but it is only recently that any attempt has met with success.
Steven Collins of the Department of Mechanical Engineering at Carnegie Mellon University and colleagues say the device acts in parallel with the user’s calf muscles, off-loading muscle force and reducing the energy consumed in contractions.
The device uses a mechanical clutch to hold a spring as it is stretched and relaxed by ankle movements when the foot is on the ground, helping to fulfil one function of the calf muscles and Achilles tendon.
People take about 10,000 steps a day or hundreds of millions of steps in a lifetime.
“While strong natural pressures have already shaped human locomotion, improvements in efficiency are still possible,” the study says. “Much remains to be learned about this seemingly simple behaviour.”
Watch the exoskeleton in action:
Why is it that we seem to think better when we walk or exercise?
Justin Rhodes, an associate professor of psychology at the University of Illinois at Urbana-Champaign, responds:
After being cooped up inside all day, your afternoon stroll may leave you feeling clearheaded. This sensation is not just in your mind. A growing body of evidence suggests we think and learn better when we walk or do another form of exercise. The reason for this phenomenon, however, is not completely understood.
Part of the reason exercise enhances cognition has to do with blood flow. Research shows that when we exercise, blood pressure and blood flow increase everywhere in the body, including the brain. More blood means more energy and oxygen, which makes our brain perform better.
Another explanation for why working up a sweat enhances our mental capacity is that the hippocampus, a part of the brain critical for learning and memory, is highly active during exercise. When the neurons in this structure rev up, research shows that our cognitive function improves. For instance, studies in mice have revealed that running enhances spatial learning. Other recent work indicates that aerobic exercise can actually reverse hippocampal shrinkage, which occurs naturally with age, and consequently boost memory in older adults. Yet another study found that students who exercise perform better on tests than their less athletic peers.
The big question of why we evolved to get a mental boost from a trip to the gym, however, remains unanswered. When our ancestors worked up a sweat, they were probably fleeing a predator or chasing their next meal. During such emergencies, extra blood flow to the brain could have helped them react quickly and cleverly to an impending threat or kill prey that was critical to their survival.
So if you are having a mental block, go for a jog or hike. The exercise might help pull you out of your funk.