Arthritis is one of those dreaded words that most of my patients seem to fear and I’m not quite sure why. Is it that they feel it is a sign that they are getting old? Is it that they think that it means that they should give up doing the exercise or activities that they love? Or is it that they think that there is nothing that they can do to help their joints and will definitely need a knee replacement in a month?
I also see a lot of patients over the age of 60 who suffer aches and pains unnecessarily because they think that it is due to arthritis and there is nothing that can be done about it. I’ve just realised that I can actually write a whole blog post about all the different options for treatment and activity changes etc. etc. that we find effective in practice to help patients regain their active lives, despite having the diagnosis of arthritis hanging over them.
Today, however, I would like to focus on the positive effect that exercise can have on slowing down inflammation, decreasing the pain you experience as well as increasing the level at which people can function.
Chronic inflammation as cause of arthritis
Inflammation is one of our body’s most powerful processes that it uses to protect us against infections and disease. It also plays a very important part in the healing process when you sustain an injury. While acute bouts of inflammation can be very advantageous, there is strong evidence to suggest that chronic, low levels of inflammation may be to blame for a whole plethora of illnesses/conditions including arthritis.
How does exercise reduce chronic inflammation?
All the causes for chronic low-grade inflammation are not yet fully understood. One of the strongest correlations, in people who does not suffer from chronic disease, has been found to be the percentage body fat a person has.
The more fat a person carries, the higher their inflammatory markers usually are. Regular exercise helps people to lose fat and build muscle, which is one of the mechanisms that researchers suspect may be behind the positive effect exercise has on inflammation.
Looking at the research, it is however obvious that this is only one of the mechanism at work when you exercise. There are also plenty of studies that show a positive effect from exercise without any changes in body mass or composition. This is important to understand so that you don’t feel disheartened if you struggle to lose weight. While losing weight is very likely to help your arthritis, you will still reap benefits from exercise even if you don’t drop any pounds.
During exercise your muscles produces high volumes of certain molecules that have been shown to reduce inflammation. These molecules are also produced at rest, but in much smaller quantities.
Lastly, exercise has also been shown to help regulate blood glucose levels. Chronically elevated blood sugar levels (e.g. when you are pre-diabetic or have diabetes) has been shown to lead to chronic inflammation in the body and exercise has been proven as an effective cure for Type 2 diabetes.
It is not just about reducing inflammation
Chronic inflammation is a very obvious cause of arthritis, but there are several other factors that can contribute to your joints taking more strain than what they should. Lack of muscle strength, flexibility and even proprioception (joint position sense – explained below) can all contribute to excessive wear and tear of your joints. So let’s take a closer look at how joints function.
Your joints are formed by the bones and ligaments that connect them. These ligaments help to stabilise the bones and stop them from moving too far. The joint surfaces are covered with slippery cartilage and the joint space is filled with very slippery fluid.
Your joints tend to be designed to carry weight or force in very specific areas and as long as you stay within those parameters they cope extremely well. Tight muscles or stiffness in joints in other parts of the body can cause a joint to repetitively overload a single area of its surface – leading to excessive wear of that piece of cartilage.
There is currently not a lot of evidence that improving flexibility can help to improve arthritis symptoms, but this is not a well-researched topic. In clinic I find that it is very patient specific and also depends on the extent of their joint damage.
Position sense or proprioception is the ability of the brain to know where its body parts are without having to look at them. There is research to suggest that you can decrease a person's pain through proprioception exercises, but they are not yet sure why. It may have to do with the fact that when a joint’s position sense is affected, it leads to less controlled joint movement which may contribute to joint wear. Don’t worry, proprioception may sound overwhelming but it’s extremely easy to retrain. For the lower limbs, for instance, simple balancing exercises work great.
Your joints are also surrounded by muscles. An obvious function of the muscles are to move the joints. A less obvious function, that most people don’t appreciate, is that the muscles also (are meant to) absorb a great amount of the shock during movement – thereby off-loading the joints and protecting them.
Don’t quote me on this, but I think I’ve read that, at the hip, 60% of the force created when walking is meant to be absorbed by the muscles that surround the hip joint. Research has also shown that people who suffered from knee osteoarthritis reported decreased pain and better function after a strength training programming focussing on their quadriceps muscles.
What types of exercise are best for arthritis?
From the above it is clear that our aims should be to reduce chronic inflammation and increase muscles strength, flexibility and joint position sense.
Research has shown that to decrease chronic inflammation the following works best:
Exercise that uses concentric muscle contractions rather than eccentric. Most cardiovascular activities use concentric muscle contractions e.g. walking, running, cycling, cross trainer, swimming etc.
Duration of the exercise – a longer duration of physical exercise leads to a better effect.
The more muscle mass you use during the exercise, the greater the effect. Swimming or using the cross trainer may be good options as they use the whole body.
Moderate exercise intensity seems to have better results than low or high intensities. As a rough guide I would say that you should aim to be breathing harder but not feel out of breath while exercising.
A lot of people find that their painful joints limit what exercise they can do. The good news is that you do not have to exercise the painful body part to get the anti-inflammatory effect. If, for example, you knees stop you from walking or cycling, you can still swim while pinching a pool buoy between your legs and only use your arms.
Speak to an experienced physiotherapist before you decide that you cannot exercise. They can be amazingly resourceful, but you also have to be willing to compromise and try new things.
For the reasons explained in the section above, your exercise programme should also include:
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Mendes R, Sousa N, Almeida A, et al. Exercise prescription for patients with type 2 diabetes—a synthesis of international recommendations: narrative review. British Journal of Sports Medicine 2016;50(22):1379-81. doi: 10.1136/bjsports-2015-094895
Runhaar, Jos, and S. M. A. Bierma-Zeinstra. "Should exercise therapy for chronic musculoskeletal conditions focus on the anti-inflammatory effects of exercise?." (2017): 762-763.
Runhaar, Jos, et al. "Identifying potential working mechanisms behind the positive effects of exercise therapy on pain and function in osteoarthritis; a systematic review." Osteoarthritis and Cartilage 23.7 (2015): 1071-1082.
Shiny, Abhijit, et al. "Association of neutrophil-lymphocyte ratio with glucose intolerance: an indicator of systemic inflammation in patients with type 2 diabetes." Diabetes technology & therapeutics 16.8 (2014): 524-530.