Sitting is the new smoking
We all know that it is important to keep fit and active in order to maintain a healthy body. But did you know that even the most committed gym bunnies could still be damaging their health by sitting too much? More and more evidence is coming to light about the association between inactivity and poor health; do a quick internet search for ‘sitting is the new smoking’ and you will find a plethora of information on the subject, emphasising that sitting for prolonged periods can lead to increased risk of heart and circulatory problems, diabetes, some cancers as well as obesity.
Image via DIY Genius
But very little of the available information on this topic refers to musculoskeletal health, despite the fact that even with the ideal workstation set-up, sitting for extended periods can damage the health of our muscles, joints and other connective tissues. This post examines the different ways in which sitting can damage our musculoskeletal system.
Posture and muscle balance
When we sit, some of our muscles, such as the front of the hips and the neck, are held in a shortened position while other muscles, such as the back muscle and the back of the hip, are held in a lengthened position. Over time, this can cause actual shortening and lengthening of those respective muscles. Standing up and moving around, even for a very short period, helps to stretch the shortened muscles and to straighten the lengthened ones, keeping the body balanced.
The movable joints in our body, such as the knees, hips and ribs, are surrounded by a protective capsule and membrane containing a substance called synovial fluid. This liquid helps to lubricate and supply nutrition to the joints. When we move our joints, a pump effect is created, pushing old fluid and waste products out and allowing fresh fluid and nutrients to cross into the joint. Movement drives this pump motion and is therefore key to maintaining healthy joints.
Vertebral discs are amazing organs which sit between the bones in the spine, making it strong and flexible. Sitting can be particularly bad for the discs, placing more strain on them than standing. Sitting with poor posture is particularly dangerous, as it places uneven yet constant strains on the discs which over time can break down their structure, which can lead to a prolapsed (slipped) disc. Taking breaks form sitting helps to change the forces placed on the discs, allowing them to recover from the strain and lower the risk of prolapse.
Proprioception describes the body’s ability to tell where the joints and limbs are orientated in space. The body does this using specialised nerve endings called mechanoreceptors which are located in various joint tissues, including ligaments and muscles, and help to detect internal forces and movement enabling the brain to know what positions our joints are in. When a ligament becomes stretched, the ability of the mechanoreceptors to detect the correct positioning of the joints can be adversely affected. Poor proprioception, particularly in the spine, has been linked with back and other joint pain, but can be avoided by sitting with good posture and taking short breaks.
Did you know that while your heart pumps blood out to your body, it is your muscles which actually pump blood back to your heart? Sitting can cause pinch points at the back of the knees, the front of the hips, the front of the neck and the front of the shoulders which compress blood vessels as they pass through these areas. This is why sitting on long-haul flights, for example, increases the risk of developing DVTs. Standing up and moving around regularly helps to maintain good circulation.
As with our blood vessels, sitting can also cause our nerves to become pinched at points in the hips, knees and chest, which may result in tingling and pain in the arms and legs. The major nerves are surrounded by fluid and contained within protective sheaths. When we move, the nerves slide within these sheaths, enabling them to move easily and free from restrictions and scar tissue. Movement also stimulates fluid flow around the nerves, helping to keep them healthy and pain free.
Not moving for prolonged periods of time will drastically lower metabolism i.e. the amount of calories that we burn at rest. This in turn can lead to weight gain which can place more strain on our joints. Short bouts of exercise will awaken your major leg muscles, making them metabolically active, even for a period of time after you become stationary again.
So remember even if you consider yourself to be a very active person, if you are sedentary for extended periods of time you should be taking short breaks from sitting throughout the day in order to:
- prevent shortening and lengthening of muscles
- prevent strains from building up at stress points in the body
- prevent the stiffening up of joints
- increase circulation
- keep our nerves moving freely
- boost metabolism
- lower the effects of stress
With little effort to keep moving throughout the day, you can help to protect both your musculoskeletal health and your general well-being.