The Characteristics, Advantages, and Disadvantages to Airbeds 

The differences between active support and passive support.

Foam and springs (and even horsehair) offer more active support. In other words they not only resist compression and stop you from sinking into a mattress past a certain point but they are also more resilient and adaptive because they "push back" against compression. Air, water, memory foam, various types of natural fibers (wool, cotton, stuffed rags, etc), and buckling column gel offer more passive support that is less resilient and can affect the ease of movement on the mattress and may not adapt as well to different sleeping positions. It is the same kind of support that would be offered by a piece of wood that was carved to your exact body profile. If this profile was carved out in a way that you were in alignment, then it would distribute your weight across the sleeping surface and in that sleeping position you would have good alignment and pressure relief... but when you change position you may no longer be in neutral alignment or may experience pressure points.

Active and passive support characteristics in air beds.

There is of course a range in each category (wool, horsehair, and memory foam offer minimal amounts of pushback) so it is not absolute. Active or passive is basically determined by two characteristics. One is how progressive the support is in the material (called support factor or compression modulus or spring rate in an innerspring) and the second is how much the material bounces back (called resilience). It is also called "pushback". Other areas of this website talk about support factor/compression modulus and resilience but in general the support factor is measured by the difference in weight it takes to compress a material by 65% of its thickness and the weight it takes to compress the same material by 25% of its thickness. This determines how quickly a material becomes firmer with deeper compression and can "stop" the heavier parts of the body from sinking down too far. Resilience is measured by how high a ball bounces when it is dropped on the material. This also tells you how springy a material is and how much energy it absorbs (called Hysteresis). Both of these contribute to a perception of the softness or firmness of a material.

Air cores are used as a support core in a bed since as a comfort layer I think most people would agree it is not too comfortable (sleeping on a bare air mattress is not most people's idea of heaven). So we need to look at it in terms of a support layer rather than a comfort layer (although support layers can add to or subtract from the feeling of comfort of the layers above).

As in anything else, there may be some people for whom an air bladder support system is absolute perfection and are quite happy with the price they paid for it. They also have the advantage of other component mattress systems where the individual layers and components can be replaced individually rather than having to replace the complete mattress. Overall though ... I would make some very careful comparisons with other types of mattresses based on real-world performance and benefits outside of "marketing" information and would question their value when compared to the alternatives.

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