What Are the Health-risk of a Sedentary Lifestyle?

Although this is a very broad topic, with many interacting dimensions, there are a few very specific health risks of a sedentary lifestyle that really stand out. These can be addressed by changing your habits to have more structured and specific activity in your life.

Risks to you heart health

A sedentary lifestyle has a direct effect on your heart health and the calibre and stiffness of the major arteries. These include your Aorta, and how effectively the lining cells of your small blood vessels function (endothelial cells), these go to all the major organs. This directly effects your risk of heart disease, your blood pressure, developing diabetes and stroke. 

Lack of physical activity reduces the normal functioning of your heart and how effectively the blood vessel cells release important chemicals that relax the blood vessels and reduce stiffness in these critical arteries. The result is that your general exercise tolerance is poor.

When you do move or exercise, it takes more heart effort than it should and your blood pressure rises during activity more than it should, further increasing your risk of heart attack and stroke.

The great news is that your body responds to what you ask it to do, but, over time.  If you exercise regularly, it responses by improving your heart function, your exercise tolerance and the function of the blood vessels to the major organs in your body, such as kidneys, legs and arms.

150 minute of moderate exercise (meaning that you are “somewhat puffed” or “can not carry on a conversation during activity”) a week is enough for the cardio effects of exercise.  This does not have to be done in one go and can be spread to 5, 30 min sessions a week.  If for you it is walking, walk at a pace that makes you puffed and it is hard to maintain a conversation with your walking partner.

Risks to your body

The biggest thing that we see at our Centre, is the reduced muscle strength as a result of a lack of strengthening exercises in sedentary people’s lives.  Most people are just not strong enough for what they ask their bodies to do in everyday life.

This means that when you do go for that walk, climb up that hill, do the weekend gardening or lift your child or grandchild, it’s more effort than it should be; Increasing your injury risk.  This leads to a vicious cycle, where you are not strong enough to do what you want, so you do even less. You get further weakness and the effort gets harder again.

In addition, improved muscle mass from strengthening exercises is a major factor in the battle against insulin resistance, leading to diabetes.  Muscle mass is a primary site of GLUT4 insulin transporters, which take the glucose from the blood stream and bring it into the muscle cells. This regulates your blood glucose level and effects your insulin sensitivity.  Strengthening exercise both increases the number and effectiveness of these sensors.

Two structured and focused strengthening sessions a week (30 min each), focusing on all the major muscle groups in the body is enough to strengthen your body and gain the benefits for a better life. The great news is that these adaptive effects are beneficial at any age.  Although the effects are slower after the 7^th decade of life (after the age of 60), the effects of training strongly outweigh the decline due to age.

Risks to your brain

Exercise, especially strengthening exercise is the only consistent aspect you can do for yourself to help preserve and improve brain function as you age.  This is due to the protection of the cardio vascular system and the function of the small blood vessels in the brain.  In addition, sleeping well, eating well and preventing chronic disease, also a result of having an active lifestyle, help protect your cognitive function as you get older.

People with higher grip strength (a proxy for overall body strength) perform higher in memory tests and reaction time.  Again, in a study, those who lifted weight at least once a week showed significant improvements in cognitive function, such as attention.  It seems to be because strength training releases several chemicals into the brain, such as BDNF, which improves nerves and brain cell health.

Social risk

The final, and not so obvious risk, is the effect of social networking and your mental wellness.  A trip to your favourite exercise session is often accompanied with a quick coffee with an exercise partner or a friend after your session.  A conversation with the instructor or other participates in the class also allows you to stretch your social “muscle” and feel like you are not alone and part of the community.  We have seen the importance of this after the long lockdown in Melbourne in 2020. Interaction between our clients with staff, the other clients and for the staff with each other was a major part of returning to normality after a long period of social isolation.

The demands of leading an active lifestyle are not complicated or arduous, nor do you have to train like an elite athlete to see the benefits.  The ideal:

• 2 strength based training sessions, which work on the major muscle groups (30 min)
• 150 minutes of moderate exercise (being somewhat puffed during exercise)

is enough and will lead you to lead the life you deserve.

Reference : Thomson, H.  Discover your Inner Strength.  The Scientist.  18^th April 2020, No 3278, p. 34-38