The Left Hand (or Fretting Hand)
Many people who have taken up bass guitar tend to have played guitar first. The only real similarities between the two are frets (and maybe the word “guitar”). When a guitar player presses a string to the fingerboard, he generally does this by squeezing the string between whatever finger is depressing it and his thumb. This works quite well for guitar where the strings are 1/3 or less the size of bass strings. Then someone picks up a bass guitar and they begin to get hand cramps, soreness, etc. Believe me, I am personally very familiar with this. I began playing guitar at 5 1/2 kept it up until about age 17. At fourteen, I started bass guitar. And the pain began, even on my short scale Hofner bass.
When I got to college and decided at the last minute to audition on double bass, I met a teacher who had studied the physiology of double bass. On a double bass, no attempt is made to squeeze the string. Depressing a string involves the entire arm and shoulder.
This is fully applicable to bass guitar. First some basic physics:
- Force travels best in a straight line.
- Force travels well in a curve.
- Curved structures carry and disperse force better than sharp angles.
Now try this with the above list in mind.
- Think of your right arm as the counter balance to the left arm. The right arm is the opposition force.
- Relax your entire left arm.
- Keep your left hand fingers curved, not angled
- Now depress the G string at the second fret
- Use a line of force to do this which begins in the shoulder blade and extends to the finger
- Move your thumb away from the back of the neck just a bit
- You should find that the pressure is now off the hand itself and dispersed over the area of the arm between the should and fretting finger
The thumb should primarily as an anchor point and a guide, not something to help squeeze a sting. When done properly, tension in the left hand should be markedly reduced.
The Best Way
The best way to handle this is to have a good teacher who understands the basics of ergonomics as it relates to bass guitar. This is one of my areas of expertise.