Walking While Balancing Yourself
March 29, 2017 11:21 AM   Subscribe

Kenyan women routinely walk while balancing 60-80% of their body weight in loads on their heads. Some bioengineers in Kenya wanted to know how they could do this so easily. One thing they discovered is that, when standing on a treadmill, the women showed no energy expenditure at all, until they started to walk. All the things the engineers learned are leading to clever exoskeletons.
posted by MovableBookLady (33 comments total) 42 users marked this as a favorite
 
I expect if the load was analysed the center of gravity would be quite close to the head and exactly centered towards the back of the head, directly over the spine.
posted by sammyo at 11:41 AM on March 29 [1 favorite]


I don't know if this is true of Kenyan women, but in other parts of Africa indigenous women apparently have developed much better posture than most Westerners.
posted by tully_monster at 11:44 AM on March 29 [3 favorites]


All the things the engineers learned are leading to stronger more robust terminators clever exoskeletons.

FTFY.
posted by Fizz at 11:44 AM on March 29 [2 favorites]


Yeah I picked this up when I lived there and do it all the time. The hard prt is getting the thing up there in the first place but I can carry a 50lb bass amp on top of my head as log as I balance it with one hand no problem
posted by STFUDonnie at 11:51 AM on March 29 [5 favorites]


I really wanted this article to have a video comparing the gait of these women vs. the Army men vs. regular Western schlubs. In slow motion/high time resolution as needed.
posted by janell at 11:52 AM on March 29 [13 favorites]


I hope these Kenyan women were generously compensated for providing key insights into the design of robotic exoskeletons.
posted by honest knave at 12:07 PM on March 29 [63 favorites]


This is pretty cool. I wish the article had expounded on the actual gait used by the Kenyan women a bit more, though. (Was anyone else weirded out by how they started calling them Kenyans and ended calling them Africans, as if the terms are synonymous? Or maybe there was more than one study location that is not mentioned in the article? Cause you'd never see an article about Mexican/Canadian/USA-ian people and alternate between Mexicans/Canadians/Americans and North Americans.)

STFU Donnie, that's awesome! How did you learn and practice, and do you notice any differences in your gait when carrying headweight that you can explain? I am deeply interested.
posted by holyrood at 12:45 PM on March 29 [3 favorites]


When walking on the treadmill, the women were capable of carrying loads equaling 20 percent of their body weight on their head with zero extra metabolic cost.

I'd suspect the equipment was faulty because TANSTAAFL.
posted by Sternmeyer at 12:54 PM on March 29


If you could get two of these women to balance on top of each other, would you have antigravity?
posted by Joe in Australia at 1:09 PM on March 29 [2 favorites]


I hope these Kenyan women were generously compensated for providing key insights into the design of robotic exoskeletons.

It's an unsurprising result, but as far as I can tell, the women were uncompensated. Heglund et al's 1995 Nature paper doesn't reference compensation at all, and a prior 1987 study by Jones et al. cited by Heglund refers to volunteers.

For what it's worth, the original studies were more pure research in locomotion and energetics, not with an eye toward any particular application other than the most obvious (i.e. how humans can efficiently carry loads on their bodies). Whether that makes the lack of compensation less unjust is another question.

The article elides that Heglund et al's initial attempt to study the issue in the late 1980s (the Fulbright/Army-funded study that it mentions) was a disaster beset by bureaucracy, riots, withheld funds, broken equipment, and failed experiments [pdf].
posted by jedicus at 1:19 PM on March 29 [9 favorites]


There are many free lunches in a universe of open systems. Walking is not 100% efficient.
posted by Nothing at 1:33 PM on March 29 [3 favorites]



STFU Donnie, that's awesome! How did you learn and practice, and do you notice any differences in your gait when carrying headweight that you can explain? I am deeply interested.


I was a kid, so I guess I just imitated what I saw. It does feel like my posture improves in the moment, as if the downward force on my crown is lining up my vertabrae. Try it with something moderately weighty, you'll see!
posted by STFUDonnie at 1:42 PM on March 29 [2 favorites]


Linda Glokhale does a lot of work in posture and gait analysis and had really useful tips for improving both. She looks at "non-industrial" cultures as models of a natural posture. Here is an article explaining Glide Walking https://gokhalemethod.com/blog/5281.
posted by elke_wood at 1:47 PM on March 29 [3 favorites]


I've tried this - and I am so jealous that I can't do it well. I once visited a village of where the women make jars - including huge ones for storing water. They are incredibly heavy, and it can take three women to lift them. But once it's well situated, they can walk quite a distance to the delivery truck. I tried, but I couldn't balance it at all.
posted by Kutsuwamushi at 2:03 PM on March 29 [1 favorite]


Interesting, but UGH, "African women." They are Kenyan women (or women from Kenya). Or just women.
posted by stillmoving at 3:00 PM on March 29 [3 favorites]


I'd suspect the equipment was faulty because TANSTAAFL.

A table supporting 20% of its mass expends no more metabolic effort than an unladen table. Which is a situation precisely parallel to that described in TFA.
posted by howfar at 3:46 PM on March 29 [3 favorites]


Interesting, but UGH, "African women." They are Kenyan women (or women from Kenya). Or just women.

There's an underlying problem with head-carrying imagery as a whole exoticizing certain cultures. Poor Western women regularly bore loads on their heads well into the 1800s (specialist uses survived into the 1960s). Yet even before the 1800s were out the image of a non-Western woman engaged in head-carrying had become established. Elites who travelled to other countries thought they were seeing something new, ignoring their home culture. They specified head-carrying as exotic instead of understanding that women throughout history had engaged in the practice, including women of their own country just a generation or two before.
posted by Emma May Smith at 4:33 PM on March 29 [8 favorites]


"Interesting, but UGH, "African women." They are Kenyan women (or women from Kenya). Or just women."

Nah, I've heard an endless amount of African women from various African countries reference women from other African countries as African women.
posted by tarvuz at 4:54 PM on March 29 [1 favorite]


Is there any reason to think that head-carrying is much easier for women than men, perhaps because of wider hips or narrower shoulders? Or is the stereotype just because women were usually the ones relegated to chores like this?
posted by Joe in Australia at 4:56 PM on March 29


I hope these Kenyan women were generously compensated for providing key insights into the design of robotic exoskeletons

Hopefully by being provided exoskeletons to help carry their daily loads.
posted by Dip Flash at 6:22 PM on March 29 [1 favorite]


Is there any reason to think that head-carrying is much easier for women than men...

At a guess it leaves at least one arm free to wrangle a baby in a carrier/wrap.
posted by ninazer0 at 8:06 PM on March 29


Plenty of male laborers head carry around the world too.
posted by fshgrl at 8:31 PM on March 29 [4 favorites]


Sternmeyer: "I'd suspect the equipment was faulty because TANSTAAFL."

If the object isn't moving (side to side or forward and back) then no work is being done whcih is quite possible on a treadmill. If they'd have had portable equipment capable of following the women while they walked on a road then you'd expect at least a minor amount of additional work to be done because the object is translating in space.
posted by Mitheral at 9:32 PM on March 29 [2 favorites]


When I was a Peace Corps volunteer in Mozambique I learned to do this. The heaviest I got was carrying a 100lb bag of cement about half a mile from the shop to my house - which didn't feel much more exhausting than walking that length would have. Subjectively, it does feel like you're "settling into" a different posture -- the way I did it was imagining a straight line from the centre of mass of the object, right down to where my vertebrae hit my pelvis. This did result in a different kind of motion from the hips downward. This motion seems to be what the researchers found; however for me the trick to learning to do this was not to concentrate on the motion, but instead to concentrate on that imaginary line down to the pelvis.

As STFUDonnie says, the hardest part by far was getting the load onto your head -- and getting something up there to cushion it so it wasn't digging into your skull. Most people used a rolled up blanket, but it took some practice to get it to the point where it stayed put over the course of the whole long walk, and if I ever failed it was because of this; it threw me off and made my motion get out of whack.

When I got back to the US, I moved to Boston and would carry my laundry down the street to the laundromat (about 1/3 of a mile) on my head. Nowadays I don't do it so much, but the trick is still with me, about 15 years later -- I think it's motor memory that doesn't go away. I never got to the point that I could do it without hands for very long (man that's impressive) but the rest of it was surprisingly not that hard to learn.
posted by forza at 12:45 AM on March 30 [5 favorites]


Mitheral: "If the object isn't moving (side to side or forward and back) then no work is being done whcih is quite possible on a treadmill"

I think it's the 'standing on a treadmill' that seems to be confusing. They just mean, standing still, they just happen to be standing still on a treadmill that's turned off.

Soon as they turn on the treadmill, at any speed, they're clearly going to be burning more calories then if they were unladen of the skull-cargo.
posted by Static Vagabond at 6:18 AM on March 30


My father was working in Nigeria from 1977-1981. It was a large crew of Russian engineers and workers. One day at a pipeline ditch a woman approached the worksite aiming to cross the ditch with a basket on her head. The lead engineer wishing to appear gallant picked it up off her head while another guy offered his hand to help her cross. The engineer picked up the basket... and promptly sat down under it's weight unable to get up again. It took three people to raise it up for her while she looked bemused. So yeah, no small feat.
posted by tatiana131 at 8:30 AM on March 30 [7 favorites]


tarvuz, yes, that's true. I have lots of friends from many countries in Africa who refer to themselves as Africans, African women, African men, etc. However, in this context, it feels fairly exoticizing and Other-izing, especially when used interchangeably with "Kenyan women," and to the exclusion of the many other cultures where women and men carry things on their heads. I'm also especially sensitive to this as a healthcare provider: the dominant discourse often refers to "black" or "African" as a risk factor, in and of itself, which can be true in some contexts but equally can lead to pigeonholing and disparities in care and outcomes. That was what gave rise to my UGH; apologies if it seemed knee-jerky or hand-wavey.
posted by stillmoving at 10:32 AM on March 30 [2 favorites]


Plenty of male laborers head carry around the world too.

I often carried 27" and up tube TV's this way when I worked at Best Buy. The 32" Sony Vegas and the first HTDV tubes with 16:9 displays were especially dense and heavy. The typical technique for carrying the smaller boxes (19" flat-tube monitors for example) was to put the heavy side facing you and have it perched up on your shoulder. That way you only have to bend to the side a little to get the center of gravity over your spine.

But the larger boxes were too big to do that so we'd just center them over our heads. To get them down, you'd either need help or some kind of platform to set it on (like another TV). The trick was to find a spot that mostly aligns with the center of gravity of the box that had solid styrofoam or other packing material behind it so you don't make a head shaped hole in the bottom of the box.
posted by VTX at 1:24 PM on March 30 [1 favorite]


This motion seems to be what the researchers found; however for me the trick to learning to do this was not to concentrate on the motion, but instead to concentrate on that imaginary line down to the pelvis.

This aligns with my experience lifting weights. There is a lot of advice like that when people write about the proper form for a lift. On the bench press, you're supposed to imaging that you're pushing the bench down rather than the bar up. You push through your heels on the dead lift vs. pushing through the center of the foot while doing squats.

Those little visualizations make a big difference that I can feel while lifting those weights. It makes enough of an impact that I can squeeze in a few more reps than I would if my form was sloppier (not to mention that I'm probably far less likely to injure myself).

The other thing I notice is that when I'm not lifting but just moving around in my normal life, I use better form doing normal stuff more without thinking about it. The most obvious example is that I don't think about lifting with my legs, I just do it that way without thinking about it. I think my posture has improved too.
posted by VTX at 1:42 PM on March 30 [2 favorites]


There is a whole big argument to be had about posture and pain, and whether "bad" posture inevitably causes pain (and this all falls under the bigger question of what is pain and why do we have it). However, I like to demonstrate to patients where they are currently bearing their weight by gently pushing down on their shoulders, and then on the crown of their head.

If you've never had it done, do swaps with a trustworthy friend - people often find that they buckle in the middle or that their head slides forwards, or tilts backwards. But once you feel it, and compare it to allowing your skeleton to take the weight (a "better" posture), there is an incredible difference!
posted by fizban at 2:39 PM on March 30


I wonder why, given that head-carrying is SO efficient, the Western world largely relies on backpacks for most distance carrying instead of teaching and learning skills like this. If women in Western countries used to do more head-carrying - why did they stop? And why haven't more men adopted head-carrying - presumably they have their own heavy loads to carry?
posted by R a c h e l at 10:22 AM on March 31


I lived in South Africa for 4 years of my early childhood, and I too picked up this habit. It's the only way I know of that one person can transport a queen-sized mattress any significant distance solo. When carrying large boxes, the only problem is that it's actually easy to forget you've got something so big on your head when you go underneath an overhang.
posted by MoTLD at 10:56 AM on March 31 [2 favorites]


I wonder why, given that head-carrying is SO efficient, the Western world largely relies on backpacks for most distance carrying instead of teaching and learning skills like this.

I suspect much of it has to do with the kinds of things being carried. One single, huge parcel? Head-carrying is the way to go. Lots of little things? Some kind of sack is going to be better.

Also, and this is not a small advantage, backpacks keep your hands entirely free for other purposes. Like, for instance, climbing up or down a steep slope. As an additional not-small advantage, backpacks will remain stable on your back even when the ground you're on is uneven and causes you to stumble.

Seems to me that head-carrying has persisted as a skill mainly in places with a lot of flat terrain where the advantages of backpacks are less important. (I also suspect that wide adoption of backpacks has a lot to do with professional/conscript militaries. The other thing having your hands free lets you do is carry and shoot a rifle. And then you get used to long marches with a backpack on, so when you get home from war you just keep using your backpack to carry things, because that's what your used to. And then it becomes a style thing that even civilians pick up on.)
posted by tobascodagama at 11:15 AM on March 31 [2 favorites]


« Older The Magnetic Fields - 50 Song Memoir: a concept...   |   “We all float down here.” Newer »


This thread has been archived and is closed to new comments