I can tune most spinet and grand player pianos while sitting down.
I am comfortable standing up to tune studio uprights and full-sized
uprights.

There are lots of player pianos in Long Island and New York City where
I work.  During these holidays a typical day for me involves pitch
raising, tuning and other service work on 2-3 badly neglected player
pianos and some non-players.

I usually do all tuning (pitch raises included) in one trip.  Most
player owners when given the option would rather have a less expensive
less stable tuning.  Right now, I don't have time to get back to them
in a second trip before the holidays for the "fine tuning."  In
one-trip tuning situations I tune the piano quickly three times because
I find the first two "passes" won't do on a badly neglected piano

This time of year I tune many players, but the hardest on my back are
those modern Aeolian consoles and some spinets.  In addition to major
tuning these modern Aeolians usually require lots of work underneath
the key bed.

I can't tune these (Aeolian) players sitting down because the spool
box and other mechanisms are in the way and make handling the mutes
difficult.  For my build, it is uncomfortable reaching the top of my
tuning lever while sitting down, especially considering the handle
has to point between 10 and 2 o'clock.  When tuning I bend my arm 90
degrees to better use large muscle groups, but this often means I have
to bend forward more than someone who uses a straight arm slapping
approach on the tuning lever.

I choose to tune these players standing up.  I use a 15-degree angle
head (not the 5-degree head) to bring the top of the lever closer to
my body.  I bend my knees and extend the lever, to avoid having to bend
my back forward.  I work quickly and concentrate 100%, so I spend less
time in ergonomically poor positions.  To my surprise, moving quickly
has improved my tuning quality.  I like tuning the high treble because
I can work more from the side of the piano.

I stretch my back before and after my day of tuning.  I try to stay
relaxed and breath fully and naturally.  The brain and muscles work
much better when they are relaxed.  Getting a good amount of sleep,
a good diet, exercise, stress reduction, being more positive and less
grumpy, a good mattress all these help my tuning to be more enjoyable.

Pain and stiffness can mean discomfort and suffering.  Professional
treatment is expensive.  Making ergonomic and other improvements have
paid off for me.  Last year about this time I was downing lots of
Advils and the pain lingered until February.  As they say, the body
will submit its bill when abused.  The day of reckoning may not be
until well in the future.  The goal is to prevent the pain from ever
coming.  So far I'm pain free with about 10 days left until Christmas,
although not without stiffness.

Bill Maguire