Choosing the right mattress firmness is one of the most important decisions you'll make when shopping for a new bed. The wrong firmness level can lead to poor sleep quality, back pain, and restless nights. Yet despite its importance, many Australians find themselves confused by firmness ratings and unsure which option will suit them best. This comprehensive guide will walk you through everything you need to know about mattress firmness to help you make an informed decision.
Understanding the Firmness Scale
Mattress firmness is typically measured on a scale from 1 to 10, where 1 represents the softest possible mattress and 10 represents the firmest. Most mattresses available in Australia fall somewhere between 3 and 8 on this scale. Understanding what each level means in practical terms is the first step toward finding your ideal match.
A mattress rated between 1 and 3 is considered soft. These mattresses allow significant sinking, contouring closely to your body shape. While they can feel luxuriously plush, they may not provide adequate support for everyone. Mattresses in the 4 to 6 range are classified as medium firmness, offering a balance between comfort and support that suits the broadest range of sleepers. Those rated 7 to 10 are firm mattresses that provide minimal sinking and maximum support, often preferred by back sleepers and heavier individuals.
Important Note
Firmness is subjective and can feel different depending on your body weight. A mattress that feels medium to someone weighing 60kg may feel softer to someone weighing 90kg.
How Your Sleep Position Affects Firmness Choice
Your preferred sleeping position is perhaps the most significant factor in determining the ideal firmness level for your mattress. Different positions place varying amounts of pressure on different parts of your body, and the right firmness can help maintain proper spinal alignment throughout the night.
Side Sleepers
If you primarily sleep on your side, you'll generally benefit from a softer to medium mattress, typically in the 3 to 6 range. Side sleeping concentrates your body weight on your shoulders and hips, which are narrower contact points. A softer mattress allows these areas to sink in adequately, preventing pressure point pain and keeping your spine aligned. Too firm a mattress can cause your shoulders and hips to bear too much pressure, leading to numbness, tingling, or pain.
Back Sleepers
Back sleepers distribute their weight more evenly across the mattress surface, making medium to medium-firm mattresses ideal, typically in the 5 to 7 range. The mattress needs to support the natural curve of your lower back while still providing some contouring for comfort. If the mattress is too soft, your hips may sink too deeply, creating an unnatural curve in your spine. If it's too firm, gaps may form under your lower back, leading to strain and discomfort.
Stomach Sleepers
Stomach sleeping places the most strain on your spine, and a firmer mattress is generally recommended, typically in the 6 to 8 range. When sleeping on your stomach, a soft mattress allows your pelvis to sink too deeply, creating an exaggerated curve in your lower back that can cause significant pain over time. A firmer surface keeps your spine in a more neutral position, though stomach sleeping is generally not recommended by sleep health professionals.
Combination Sleepers
If you move between different positions throughout the night, a medium firmness mattress in the 5 to 6 range often works best. This provides enough versatility to accommodate various positions while maintaining adequate support. Look for mattresses with responsive materials that adapt quickly as you change positions.
Key Takeaway
Side sleepers generally need softer mattresses, back sleepers need medium-firm, and stomach sleepers benefit from firmer options. Combination sleepers should aim for medium firmness.
Body Weight Considerations
Your body weight significantly affects how you experience mattress firmness. The same mattress can feel completely different to people of different weights, which is why generalised firmness recommendations don't always work for everyone.
Lighter individuals, those under approximately 60 kilograms, don't exert as much pressure on the mattress surface. As a result, they may find that firm mattresses feel too hard and fail to provide adequate pressure relief. Lighter sleepers often benefit from mattresses one firmness level softer than general recommendations suggest.
Average weight sleepers, roughly between 60 and 100 kilograms, can typically follow standard firmness recommendations based on their sleeping position. Most mattress firmness ratings are designed with this weight range in mind.
Heavier individuals, those over 100 kilograms, compress mattress materials more deeply. This means a medium mattress may feel softer than expected, and firmer options are often more comfortable and supportive. Heavier sleepers should also look for mattresses with higher density foams or reinforced coil systems that can maintain their structure under greater pressure.
The Role of Personal Preference
While sleep position and body weight provide excellent starting points, personal preference ultimately plays a crucial role. Some people simply prefer the feeling of sinking into a plush mattress, while others favour the solid support of a firmer surface. Neither preference is wrong, as long as the mattress maintains proper spinal alignment.
Consider your previous mattress experiences when making decisions. If you've slept well on a particular firmness level in the past, that's valuable information. Conversely, if you've experienced pain or poor sleep on certain mattresses, try to identify whether firmness was a contributing factor.
Health Conditions and Special Considerations
Certain health conditions may influence your ideal mattress firmness. People with chronic lower back pain often benefit from medium-firm mattresses, which provide enough support to maintain spinal alignment while offering sufficient pressure relief. Research published in various sleep medicine journals has found that medium-firm mattresses can help reduce back pain compared to both very soft and very firm options.
Those with conditions like fibromyalgia or arthritis may need softer mattresses to minimise pressure on sensitive joints and muscles. However, it's important to balance softness with support to prevent aggravating symptoms through poor spinal alignment.
If you have specific health concerns, consulting with a healthcare professional before making a mattress purchase can provide personalised guidance tailored to your needs.
Testing and Trial Periods
Given the subjective nature of firmness, testing mattresses before purchase is highly valuable. Many Australian retailers offer in-store testing opportunities where you can spend several minutes lying in your typical sleeping position. However, a brief store test cannot fully replicate sleeping on a mattress every night.
This is why trial periods have become increasingly important. Many mattress companies now offer 100-night or longer trial periods, allowing you to test the mattress in your home environment before committing fully. Take advantage of these trials whenever possible, as they provide the most accurate way to determine whether a firmness level truly suits you.
Shopping Tip
When testing mattresses in-store, spend at least 10-15 minutes on each option in your natural sleeping position. First impressions can be misleading.
Adjusting Firmness After Purchase
If you purchase a mattress and find the firmness isn't quite right, there are some options for adjustment. A mattress topper can add softness to an overly firm mattress, with memory foam or latex toppers providing additional cushioning. Conversely, a firmer topper or placing a piece of plywood beneath your mattress can help firm up a surface that's too soft.
Some modern mattresses also feature adjustable firmness through flippable designs with different firmness levels on each side, or removable comfort layers that can be swapped for different feels.
Conclusion
Selecting the right mattress firmness is a personal journey that depends on your sleep position, body weight, health considerations, and individual preferences. Use this guide as a starting point, but don't be afraid to trust your body's feedback. The right mattress should feel comfortable from the first night and support restful sleep that leaves you feeling refreshed each morning. Take advantage of trial periods whenever possible, and remember that investing time in finding the right firmness will pay dividends in better sleep for years to come.