I have been fascinated with the topic of carrying things on one’s head for the last several years. I took a class in 2010 by Esther Gokhale who recommends adopting the neck posture she observed in women carrying pots on their heads in India and Africa. This is a posture in which the head is aligned more directly above the torso than most people in America are accustomed to. This retracted neck posture seems like a good antipode to the vulture neck most people with desk jobs tend to sink into over time
But what about loading? The retracted neck posture shows up everywhere in the world that people carry things on their head, but does it allow them to carry things pain free?
From Jager et al. 1997
From Echarri et al. 2002
In 2010 a review investigating the implications of water carrying for health was written by Jo-Anne Geere (a PT), Paul Hunter and Paul Jagals from the UK and published in the Journal of Environmental Health. They summarized the sparse literature on water carrying in a page and a half.
Here are some of the results of their literature review:
- Cervical spine degeneration has been documented at a young age in coolies and porters who regularly carry heavy loads on their head (Siddarth 2010, Jager 1997, Jumah 1994, Echarri 2002)
-Evidence of osteoarthritis on CT scan in the first two vertebrae of the neck was 91.6% in a group of 107 head-loading Indian porters (AVG age 32.6yrs) but only 6.8% in an Indian control group (people who came to the doctor for sinus infections, AVG age 34.6yrs) (Siddarth 2010)
-81.3% of the 107 Indian porters complained of some pain related to their job. The most common complaints were neck pain at the base of the skull (69.7%), a loss of neck range of motion (49.5%), and neck crepitus, ie cracking or popping with movement (48.6%). There was no correlation between severity of degeneration and complaint of symptoms.
- Women and children have reduce injury tolerance for cervical compression compared to men (Nuckley 2003 & 2007, Marras 2002 & 2003, Stemper 2003 & 2008, Kumaresan 2001)
- Many of the people interviewed who carry heavy loads on their head report that it hurts their back or neck. (Siddarth 2010, Llyod 2010, Geere 2010).
Women in Limpopo region of South Africa carrying water.
The research team also conducted a pilot study in which they interviewed 29 people that they observed carrying water in six rural villages in the Limpopo Province of South Africa. Here are some of their pilot-study findings reported as averages as well as how widely the data varied from that average (ie standard deviations: SD)
- Water carrying was mostly performed by women or children carrying containers on their head
- AVG filled-container weight: 43 pounds. (SD6.1) The heaviest was 60lbs.
- AVG filled-container weight: 41% of body weight (SD 14.6)
- AVG carrying distance: 0.2 miles (SD 0.11)
In the interviewa they asked open-ended questions such as “Can you tell me about your experiences carrying water?” and “How do you think carrying water affects you?” So what do you think, was carrying water painful? Or did they respond as most (but not ll) Peruvians did when I asked them about pain with lifting “estoy acostumbrado.” (I’m used to it)
- 69% of participants (20 of 29) reported spinal pain during water carrying.
What This Study Proves
What does this prove? The only thing we can know for sure is that most of the people who have been interviewed in various parts of South Africa (Lloyd 2010 and Geere 2010) and the group in India (Siddarth 2010) said carrying water hurts. Nothing more. I find it interesting that none of the 35 porters included in the Sierra Leone porters reported any neck pain or discomfort despite significant joint degeneration at a young age. For me it is a reminder not to assume that a task is either painful or pain-free simply based on the mechanics.
This x-ray is from a study on coolies who carry enormous weights on their heads (like 100 pounds) in west Africa (Jager 1997). This subject on the right happened to have a straight spine. The subject on the left did not. Both had degenerative changes. The authors unfortunately did not measure the curve in the neck so we don’t know if it had and relationship to degeneration.
Here is an MRI of my cervical spine from 2010. I am lying down on my back and doing a chin tuck. I was surprised to find that my spine was actually straight. I can’t say that a straight spine is better than one with a smooth curve but it does show that I am not stuck in a curved position.
The current evidence is insufficient to answer my question because the authors were not recording neck posture and the methods were not rigorous enough to make any firm conclusions about the relationship between carrying things on the head and pain.
We also don’t know how important the weight of the load and the frequency of loading matters here. I suspect it is the critical variable.
So it seems that carrying heavy loads on your head for years will result in more rapid cervical degeneration. Although this degeneration does not correlate with symptoms, the current state of evidence indicates that many people who carry heavy loads on their heads do find it painful.
At this point I would like to mention the perceptual nature of pain. Whether one finds a particular movement or behavior painful is closely related to how one view that behavior. If a child views carrying water as a lowly chore, or an adult views it as a symbol of their poverty they may he more likely to find it uncomfortable or even painful.
How This Data Affects My Life
I use head loading to carry awkwardly shaped (and often heavy) objects short distances, such as a 50lb, 62″ box through a crowded airport or dock. I’m not worried about this activity causing pain or damage because 1) I do it infrequently, 2) I use what I believe to be the optimal posture for carrying loads on the head, and 3) I have a lot of fun doing it.
Me at with box-full-o-tandem-bicycle on my head. I suppose I could hire people to carry it around for me but taking more of the burden on myself makes me feel more abled. See my post on the human-environment interaction and disability
for more on this.
The hippo water roller looks like a great solution to reduce the amount of cervical degeneration caused by carrying heavy loads of water on one’s head everyday from a young age.
Echarri JJ, Forriol F: Effect of axial load on the cervical spine” a study of Congolese woodbearers. International Orthopaedics 2002, 26:141-144
*Geere JL, Hunder PR, Jagals P: Domestic water carrying and its implications for
health: a review and mixed methods pilot study in Limpopo Province, South Africa. Environmental Health. 2010, 9:52
Geere JL, Mokoena MM, Jagals P, Poland F, Hartley S: How do children
perceive health to be affected by domestic water carrying? Qualitative
findings from a mixed methods study in rural South Africa. Child: care,
health and development 2010
Jäger HJ, Gordon-Harris L, Mehring UM, Goetz GF, Mathias KD:
Degenerative change in the cervical spine and load-carrying on the
head. Skeletal Radiol 1997, 26:475-481.
Jumah KB, Nyame PK: Relationship between load carrying on the head
and cervical spondylosis in Ghanaians. West Afr J Med 1994, 13:181-182.
Kumaresan S, Yoganandan N, Pintar FA: Pediatric neck injury scale factors
and tolerance. Biomed Sci Instrum 2001, 37:435-440.
Lloyd R, Parr B, Davies S, Cooke C: Subjective perceptions of load carriage
on the head and back in Xhosa women. Appl Ergon 2010, 41:522-529.
Marras WS, Davis KG, Jorgensen M: Gender influences on spine loads
during complex lifting. Spine J 2003, 3:93-99.
Marras WS, Davis KG, Jorgensen M: Spine loading as a function of gender.
Spine 2002, 27:2514-2520.
Nuckley DJ, Van Nausdle JA, Eck MP, Ching RP: Neural space and
biomechanical integrity of the developing cervical spine in compression.
Spine 2007, 32:E181-187.
Nuckley DJ, Hertsted SM, Ku GS, Eck MP, Ching RP: Compressive tolerance
of the maturing cervical spine. Stapp Car Crash J 2002, 46:431-440.
Stemper BD, Yoganandan N, Pintar FA, Maiman DJ, Meyer MA, DeRosia J,
Shender BS, Paskoff G: Anatomical gender differences in cervical
vertebrae of size-matched volunteers. Spine 2008, 33:E44-49.
Stemper BD, Yoganandan N, Pintar FA: Gender dependent cervical spine
segmental kinematics during whiplash. J Biomech 2003, 36:1281-1289.
From Jager 1997
From Echarri 2002
Hi, this seems a fair summary of our review and quite sensible views to take from it and the other information you have collated. Thanks for acknowledging our work. We have done a little more research now, hopefully will understand the complexity of the issues a bit more from it and aim to be publishing in the next year or so.
If you are still interested in the topic another good review was recently published by Porter et al ‘Health impacts of pedestrian head-loading: a review of the evidence with particular reference to women and children in sub-Saharan Africa.’ Authors Porter G, Hampshire K, Dunn C, Hall R, Levesley M, Burton K, Robson S, Abane A, Blell M, Panther J.
Journal: Soc Sci Med. 2013 Jul;88:90-7. doi: 10.1016/j.socscimed.2013.04.010. Epub 2013 Apr 17.
Best wishes, Jo Geere
Thanks for the update Jo, I look forward to reading your upcoming report!
I am very curious to find the balance between what appears to be the dangerous sedentary behavior of the developed world and the dangerous repetitive loading of the developing world.
Me too, that is what I’m trying to do my PhD on in relation to water access. I’ll see if I can find the Porter et al paper for you,
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