The Evidence: Scientific Studies

Study 1

The Study of Posture & Pressure on the Human Form on Comparative Bed Types

The following information comprises excerpts from the full study. Enquiries for more information pertaining to these studies should be directed to [email protected]

Download the study White Paper here


Since the inception of the ‘Innerspring Mattress’ there has not been a major improvement in ‘a mattress’s supportive capabilities of the human body’

By 1998, Mario Piraino, a Structural Engineer, tested thousands of people on various beds. He soon suspected, then formed the belief, that in fact:

  1. Modern mattresses’ supportive capabilities are not much better than those of 50 years ago.
  2. The terms ‘soft, medium and firm’ are (relative only to the ‘feel’ of the mattress, not support as often claimed) simplistic and basically meaningless.
  3. The words ‘comfort’and ‘support’ are often misused and intermixed, and…
  4. Many claims and bed descriptions made by manufacturers and retailers about their bed’s ‘supportive’ and ‘pressure reducing’ qualities are often misleading and sometimes plainly untrue. The most common situation is where a manufacturer will illustrate a person lying on a mattress with a straight spine and yet the observations of the time suggest this was not achievable.

On the 8th of December 2005, the first truly comparative testing of a wide range of mattress types from the best known industry brands was carried out openly in the Bio Mechanics Research Laboratory of one of Melbourne’s Public Universities.

It was conducted using proven scientific research protocols i.e. testing each subject with the same measuring equipment, on the same day, by the same research staff, etc. the only variable in each case being the different types of beds being tested.

The testing involved measuring ‘the body surface pressure’ and ‘the skeletal alignment’ of 2 subjects (1 female and 1 male) of average weight and shape on each of the 12 different bed systems.


In a standing position a neutral posture is achieved where the spine is naturally straight in the vertical plane and the hips and shoulders are straight in the horizontal plane. Of course, this assumes the body is symmetrical where there are no underlying pathologies such as scoliosis.

It is assumed that a neutral posture imposes the least amount of stress on the vertebral column. That is, asymmetrical loading of the spine does not occur

When the human form, with variations in weight and shape along the body, is supine on a support surface such as a mattress, areas with more mass will sink lower than other lighter areas. Wider areas that are lighter, such as hips and shoulders will not sink as required and act as bridging points. The vertebral column, therefore, is no longer in a neutral position and is loaded asymmetrically.

Testing Protocols

The testing procedures were conducted in an independent Biomechanics Laboratory by Senior Researcher Noel Lythgo (PhD).

A representative male (mass = 79.6kg, height = 172.5cm) and female adult (mass = 62.8kg, height = 165.5cm) participated in this project. The alignment of the vertebral column, hips and shoulders was recorded for 12 bed types manufactured by major companies of varying construction types. Subjects lay on their side in the same relative position for each bed type.

Bed Models Testbed

  1. Sleepmaker Classic Miracoil 5 zone Mattress/Platform Base
  2. Sealy Posturepedic Prestige/Platform Base
  3. 7 Turn Coilflex Standard Mattress/Platform Base
  4. 7 Turn Coilflex Standard Mattress Variable Zone/Platform Base *
  5. Endorsed Medium Firm 3 Zone/Platform Base
  6. 5 Zone Pocket Spring/PlatformBase
  7. Simmons Beauty Rest Physio Supreme Comfort/Platform Base
  8. Pocket Spring Variable Zone/Platform Base
  9. Tempur-pedic (20cm) VE /Platform Base
  10. Tempur-pedic (20cm) VE /Variable Support Base **
  11. Latex Mattress (17cm)/Platform Base
  12. Latex Mattress (17cm)/Variable Support Base ***

*Denotes Mattress Type C. Variable Support In Mattress
**Denotes Mattress Type I. with Variable Support “Under Mattress”
***Denotes Mattress Type K. with Variable Support “Under Mattress”


A Vicon (Oxford Metrics) 460 Motion Measurement System was used to record the 3D spatial coordinate position of spherical (9mm diameter) passive reflective markers placed on the following known anatomical landmarks: (1) shoulder region – right and left scapula (mid-spine region of the scapulae); (2) vertebral column – spinous processes of C7, T8, T12, L3, L5; (3) sacrum (median sacral crest); and, hip region – right and left posterior superior iliac spines.

Bed Testbed

Test Component 1 ‘ Posture Profiles

The subject was placed in a standing position.

This Control Benchmark was captured and is represented by the yellow dots on each of the data sheets as shown on the example below.

The subject was then progressively placed on each of the bed types tested and captured. This posture profile is represented by the blue marks on each of the data sheets as shown on the example in Section 2, ‘How to Read the Test Results.

This component of the testing procedures was used to identify the degree of variation in posture including spinal alignment and relationship of shoulders and hips to the plane of the spine.

Test Component 2 ‘ Pressure Mapping

Each bed was fitted with a Pressure Mapping Unit to record the variations of pressure along the human form.

The pressure imaging was captured co-inciding with the capture of the Posture Profile.

This image identifies peak pressure zones (highest level is red zones) and no pressure zones (lowest level is white). Refer to the Pressure Mapping Image in Section 2, ‘How to Read the Test Results.”

This component of the testing procedures was used to identify the distribution of pressure along the human form and variations in pressure on different bed types.

Test Results

Conclusion By Dr Noel Lythgo

I conducted Biomechanics consultancy work for Spinal Bed Support Systems Pty Ltd. This work investigated the alignment of the body on 15 bed types that are commerciall available. Information about the position of the back (vertebral column), shoulders and pelvis in 3-dimenionsal space was recorded by a VICON motion analysis system. The results show the variable support system to align the body in a position similar to that achieved when standing (neutral position). The mean difference, for example, in the line of the back from lumbar vertebrae 5 to cercical vertebrae 7 was 1.5o, whereas it was 7.2o for the other beds. This demonstrates that the variable bed support system places the back in a position similar to standing whereas the other beds place the back in greater lateral flexion.

Dr Noel Lythgo (PhD)

How to Read the Test Results


Comparative Analysis (Summary)

By comparing imaging recorded on different bed types it is apparent that both posture and pressure change on each of the mattress types.

This assists in determining which mattress types are most effective at:

  • Reducing peak pressure points, particularly at hips and shoulders.
  • Providing increased support in the lower back determined by an increase of pressure.
  • Improving spinal posture denoted by the alignment of the blue dots to the original “Control Benchmark” yellow dots.

The reader of this report is invited to draw their own conclusions from the following profiles

Individual Bed Test Reports

Click to view illustrations of Posture and Pressure with and without Variable Support:

L8 Simmons Pocket Spring Physio Endorsed L4 Spinal Support Pocket Spring

The above offers only a sample of the Test Results obtained in measuring Comparative Pressure and Posture Plots for each mattress model using 1 x male & 1 x female..