Mattress indentation as a measure for spinal support

It is widely recognized that the spine shape in lying position should be similar to the spine shape in upright position to have a good body support while sleeping. However, it is not always easy to quantify the spine shape while lying on a mattress. This howto document describes how mattress indention measurements can be used together with information on the body shape as a tool to evaluate the spinal support on one or more sleep systems.