More on Ergonomics

catching the shuttle - shuttle tip slides between index and middle finger, thumb can provide braking action to the bobbin.  Index finger than moves to the point to return the shuttle the other direction

ready to throw the shuttle from right to left.  I have large hands but some shuttles have 'points' that are too long even for my fingers.  If you have small hands, some shuttle makers produce smaller shuttles with quite 'blunt' points that may fit your hand 'better' than this standard Leclerc in the photo.  Most of the motion of the throw comes from the push of my index finger with a small flick of the wrist.  The wider the warp, the more 'flick' may be required.  But I can easily throw a shuttle across a 60" wide warp using this motion.

Brief look at wrist positions

Almost all on line references about 'neutral' hand positions are in relation to computers - keyboard and mouse use.

So instead I am going to elaborate a bit on general ergonomics.

Generally speaking, the muscles work better when they are straight, so a straight line from joint to joint is the recommendation.  I just watched a video that talked about being able to use 100% of ones strength in the 'neutral' alignment and how strength drops off when that straight alignment is not used.

(Want to Google yourself?  I found the 'best' results by using the key words 'neutral hand position')

The lower arm has two bones, which are parallel.  The body is wonderfully flexible (when it is healthy) and part of our range of motion comes from being able to rotate our arm between the elbow and the hand.  The thing is, as we rotate our hand from a thumbs up to a thumbs down position, we do that by twisting those two bones and the muscles are no longer in straight alignment from elbow to wrist.  The more extreme the rotation, the more muscles, from neck/shoulder to hand, are used.

(Remember the children's song - about how every joint is connected to the next joint.)

The twisting means that muscles that were relaxed are now engaged.  How much will depend on how far the rotation goes, and how much strength one needs to use to do the task.

Once all of the muscles from neck, through shoulder, upper arm, lower arm - plus the small hand muscles - are engaged, we are working under load.  When we then do the same motions, over and over and over again?  Muscles tire.  If they get really tired, inflammation may begin and if that inflammation lasts for any length of time (how much depends on the particular body), muscle tissue can become damaged.

This is referred to as 'repetitive stress injury'.

This principle applies to all of the muscles in our body, not just the shuttle throwing ones.

Things to watch for are turning your body at the waist repeatedly, using your right hand stretched out to your far left (like in winding a warp on a warping board - one reason so many people recommend a mill or other warp winding device.  Of course each of those tools comes with caveats.)

Working with your hands over shoulder height (for example a warping board that is mounted too high).  This becomes very tiring.  I have linked to a rock climbers blog with more info on this in a previous post on ergonomics.  He makes the case that when the hand is held above the head for a lengthy amount of time, it becomes harder for the heart to pump blood upwards to the hands, causing muscle fatigue.

Working with your hands stretched out in front of you.  This is a huge no-no for me with my whiplash injuries.  It only takes a couple of minutes of using a loom with levers arrayed across the castle of a loom for my neck to begin objecting.  If I don't stop, the objections become louder and louder (as in increased pain).  Or using a lever loom with levers at the side of the castle.  Same thing.

I've talked at length elsewhere about sitting 'properly'.  My teeth gnash when I see weavers sitting in chairs (ordinary chairs are generally 'raked' - as in your bottom tends to be somewhat lower than level - which is fine for ordinary sitting, not good for weaving.)

Recap on sitting - elbows higher than the breast beam to prevent lifting shoulders, hips higher than knees, sit on sitz bones, not coccyx, engage abdominal muscles.  Exactly how you sit will depend on the loom.  Front hinged treadles and back hinged treadles will take slightly different positions.

Now all of these recommendations are based on the assumption that a person is able to do them.  Not everyone comes to the craft in the peak of health.  Some people use weaving as physical therapy.  (My physiotherapist was delighted with my recovery from a badly broken ankle because I had begun weaving even before I was given the green light to put my full weight on it.  Which broke most of the adhesions, giving me better range of motion than most people who don't have a floor loom to force them to do that.)

Not everyone comes to the craft uninjured.  Like with my whiplash injuries.  Some people are more prone to inflammation than others and need to be very careful they don't set off a chain of events that can become debilitating.

Everyone must work within the limits of their body.  As we age, things like inflammation can crop up more quickly.  Or we acquire yet more injuries.  Or like me, an adverse drug effect that attacked my muscles and joints.  Kept me alive, but...

Bottom line?  If you feel pain, STOP!  Yes, I'm yelling.  Weaving is not a 'no pain, no gain' activity.  It is a 'stop before you hurt yourself'.  Go do something that requires different muscles.  Or just plain rest.

My recommendation is this - if there is a more ergonomic way of doing something, start doing that before you set habits that will be extremely difficult to break if such time comes that you do have an injury or need to change from that habit to something friendlier to the body.  You may be young and uninjured now.  That may not last.  Or it may.  We don't know what the future holds.

As always, YMMV.