ergonomics, guitar arpeggios, mac keyboards and mice

April 13, 2011

For the longest time I've been plagued by a chronic inability to play arpeggios on my guitar using my index finger. Playing a simple pim has at times become almost impossible, yet pma is fine and precise. Similarly playing scales with 'im' alternation has become very difficult, my speed being less than half that when playing with ma. Things have got so bad that I've resorted to hybrid picking, that is holding a plectrum between my thumb and index finger and using the other three fingers when playing fingerstyle pieces.

In addition I've noticed this issue with my right index finger beginning to affect my typing. Now I'm far from being a speedy typist, but I do touch type and thought I had found a comfortable keyboard to work with (the mac mini keyboard) after trying many other keyboards. The main ergonomic advantage of this keyboard is that by having very little width, particularly by not having a numeric keypad it allows you to position the mouse close to your body. The consistency with my laptop keyboard is also an added bonus.

In the last couple of days though, I've had a bit of a recovery with my guitar, for some reason yesterday I was able to play those arpeggios again, I believe this was to do with the rotation of my right forearm. This wikipedia article provides some reference material for the following analysis.

Rotation of the forearm moving the palm from a face up position to a face down position is called pronation. The opposite movement is called supination. It seems that I have fallen into a pattern of supinating my forearm when playing This also is happening when I am typing, and particulary when I am using a mouse. Here my hand naturally falls to the right side of the mouse, leaving plenty of space for me to use my index finger to press and scroll. The mouse I'm using on this machine has a scroll wheel. When I use this, I use my index finger to scroll, it is directly above the wheel, but this means I have supinated my forearm, and to some degree let my arm collapse and flatten. This feels very comfortable, but I fear it is detrimental.

The mac keyboard encourages other habits which I think are detrimental to my guitar playing. My default typing position with this keyboard is one with the base of my palms on the table and my wrists adducted so that my fingers are parallel to the side of the keyboard. This is supported by supinating forearms and hunched shoulders. Such a a posture puts the fingers in a convenient location to hit the keys with some degree of accuracy, but is very detrimental to overall posture. Fortunately as a programmer I don't actually do that much typing (the main emphasis is on thinking), however when programming I am much more likely to be unaware of bad ergonomics - my attention is elsewhere.

The amount of complexity involved in playing a note on a guitar is phenomenal. Being dysfunctional and unable to do simple movements that others find easy, is very frustrating. After all I only want to play the guitar reasonably well, not study anatomy, ergonomics et al. It seems though that with my natural lack of grace and physical control that this sort of understanding is fundamental to making progress. Perhaps there is a chance that I will be able to play fingerstyle again.