Knee flexibility, or should I say inflexibility, is a common problem that affects people of any age.
There may be long-standing muscle tightness, problems following a knee injury or even restriction in the joint. Any of these can lead to knee pain, swelling, instability and decreased function.
Here, we look at the most common causes of knee stiffness and tightness, and will share with you loads of great tips for how to improve knee flexibility.
Reduced knee movement is often due to a combination of:
Learn more about the Causes of Knee Stiffness >
There are lots of different ways to improve knee flexibility depending on what is causing your restriction.
Here some suggestions of things that can help, but if your knee movement is limited, you should get checked out by your doctor.
One of the most popular and effective ways to improve knee flexibility is exercises. These may include a combination of:
Stretches are the most commonly used too for improving knee flexion and typically focus of changing the length of a musculotendinosus unit i.e. increasing the distance between a muscles points of origin and insertion. Stretches also help reduce the tension through a muscle.
Static stretches are used most commonly, where a muscle is held under tension at the point where a stretching sensation is felt in the muscle. This position can be held by the individual or a partner and should be repeated.
There is lots of different information out there about the best ways to stretch, but research shows that the most effective way to improve knee flexibility with stretches is to:
Our joints are designed to move and our muscles are designed to be used. If we don’t keep active, then joints get stiff and muscles get weak and tight which can lead to knee problems.
Regular exercise helps to:
Government guidelines recommend:
The position that you sit or lie in can have a big impact on knee flexibility. Whether you are sitting down for long periods because you have an office job, have a sedentary lifestyle or are ill or infirm, sitting down for long periods with your knees bent can lead to:
But, there are some simple things you can do while sitting to improve knee flexibility:
Applying a heat pack to the knee can help improve knee flexibility and reduce pain. Heat increases blood flow to the area bringing in fresh oxygen and nutrients to the joint.
Heat is also a natural analgesic and can feel really soothing as well as helping your muscles to relax, thus improving knee range of motion.
Use a heat pack or hot water bottle (with a cover on) and mold it around your knee leaving it in place for 10-20 minutes at a time.
Safety Information: do not use heat if you have had a recent knee injury or surgery as it can increase inflammation, or if you have any problems with circulation or decreased sensation. Take care not to burn yourself.
The knee joint contain a substance called synovial fluid which works as a natural lubricant. Think of it like the oil in your car. It helps the knee to move freely, reducing friction between the bones. This natural lubricant is produced when we move.
Keeping the knee still for long periods slows the production of synovial fluid and the joint can start to dry out. This is one of the reasons why knee pain is often worse first thing in the morning or after sitting down for long periods. Many people find that when they first get up, the knee feels very stiff and sore. But once they’ve been moving around for a few minutes and the dried out joint starts producing more synovial fluid, the knee actually eases up and knee flexibility improves.
So, to help avoid those stiff painful first steps, spend a couple of minutes, before getting up, simply bending and straightening your knee through a comfortable range. Get the fluid pumping in to the joint so it is nice and lubricated before you get up. You’ll be amazed what a difference it can make to your knee range of motion and pain.
Doing exercises in water can really help improve knee flexibility and strength. Ideally, you want to be in a hydrotherapy pool where the water is warmer (33-36o) than a normal pool, but if you don’t have access to one, use your local pool.
Hydrotherapy can really help with knee pain and stiffness as the water:
Here are some ideas of things you can do in a pool that can help improve knee flexibility:
Massage can be used to increase knee flexibility, increase range of movement and improve performance. Common causes of reduced knee flexibility include muscle overuse, tightness, tension, spasms and inflammation.
A range of massage techniques can be used to help improve knee flexibility:
Knee massage can also have the added bonus of improving relaxation which can help to reduce stress and anxiety, which can reduce pain levels.
Pain affects our body’s ability to move. Our natural reaction is that if something hurts, we avoid doing it, but pain is not the same thing as damage. Think of a paper cut – it can really, really hurt, but there is very little actual damage. Pain can be our body’s way of checking with us that we really do want to do something.
People often worry that taking painkillers or anti-inflammatories might mean they do something they shouldn’t, and mask warning signs of further damage. But this is not the case - our bodies are cleverer than that!
It is really important to get knee pain under control so that you can get the joint and muscles moving. It is much better to take medication regularly to reduce pain levels and inflammation so you can increase your activity levels and do exercises to improve knee movement and strength. If you are doing something that really is putting your knee at risk, your body will tell you!
Joint mobilizations are manual techniques performed by a physical therapist to get a joint moving which helps:
When the knee moves normally, it doesn’t just bend and straighten. The knee joint also needs to be able to roll, spin and glide to allow it to move freely, fully and smoothly. These are much smaller, more subtle movements but are essential for full knee range of motion.
Knee stiffness is often linked to restricted roll, spin and glide movements at the joint. Joint mobilizations help to restore these movements to improve knee flexibility and focus on attaining full, pain-free joint motion. Joint mobilizations should only be carried out by an experienced physical therapist and are most effective when combined with a home exercise programme.
If your knee pain and stiffness is linked with inflammation, changing your eating habits may help. It won’t be a magic cure, but diet can help reduce the frequency and intensity of knee flare-ups. And the good news is that anti-inflammatory foods are really healthy too!
Research has shown that the following foods can help to reduce inflammation and may therefore help to improve your knee flexibility:
You should also avoid the following foods:
Corticosteroid injections can help to reduce joint pain and inflammation, so your doctor may recommend them to help improve your knee flexibility.
Knee injections are a great way to target fast-acting medication to a precise area often making them more effective than oral medication, and they tend to have fewer side effects.
A small amount of cortisone combined with local anaesthetic is injected into the knee joint. Effects are often felt almost immediately but there are a few possible side effects to be aware of. LEARN MORE >
If you are recovering from major knee surgery, such as a knee replacement or ACL reconstruction, then your surgeon may encourage you to use a CPM machine to help improve knee flexibility, particularly flexion.
CPM stands for Continuous Passive Motion and is a device that slowly, repetitively bends and straightens your knee. Your muscles are relaxed with the machine doing all the work.
The CPM can be set to move between different ranges of flexion and extension, so you can gradually increase the knee motion range by changing the settings.
CPM’s are most commonly used to get the knee moving immediately after knee surgery to help reduce post-operative stiffness and the build-up of scar tissue. Patient’s often like them because it gives them the feeling that they are doing something, even when resting and it can give them more confidence to move their knee.
Using a CPM after knee surgery e.g. total knee replacement has been show to improve knee movement in the first few days and weeks of recovery however there is no evidence of any longer-term benefit. There is also the chance that CPM use encourages people to stay in bed rather than being more active with their therapy.
PNF stands for proprioceptive neuromuscular facilitation and is a special type of progressive stretching involving contracting and relaxing muscles.
PNF uses the body’s inbuilt reflexes to aid stretching. Whilst it has been shown to be one of the most effective ways to stretch, to do it properly you need a partner to help you which can make it impractical.
PNF stretching should be taught by a physical therapist to ensure appropriate and correct technique so you can safely improve your knee motion range.
There are lots of possible causes of knee stiffness and reduced knee motion range.
The best ways to improve knee flexibility are:
Page Last Updated: Sept 10, 2020
Next Review Due: Sept 10, 2022
1. Database of Abstracts of Reviews of Effects (DARE): Quality-assessed Reviews. Therapy interventions for improving joint range of motion: a systematic review. SL Michlovitz, BA Harris, and MP Watkins. Review published: 2004.
2. Saudi Journal of Sports Medicine. Extended sitting can cause hamstring tightness. G Fatima, M Mustafa Qamar, J Ul Hassan, A Basharat. 2017
3. Australian Government Department of Health. Australia's Physical Activity and Sedentary Behaviour Guidelines and the Australian 24-Hour Movement Guidelines. 2019
4. Internation Journal of Sports Physical Therapy. Current Concepts In Muscle Stretching For Exercise And Rehabilitation. P Page. 2012
5. Journal of Physiotherapy. Strength training alone, exercise therapy alone, and exercise therapy with passive manual mobilisation each reduce pain and disability in people with knee osteoarthritis: a systematic review. MJ Jansen, W Viechtbauer, AF Lenssen, EJM Hendriks, RA.de Bie. 2011
6. VeryWell Health. CPM Machine After Knee Replacement. J Cluett. 2020