Consequences of a Sedentary Lifestyle

A sedentary lifestyle is one involving little or no physical activity. In the UK, sedentary behaviour is increasing due to technology, desk-based jobs and screen time. For Edexcel GCSE PE, you must understand the full range of health consequences — physical, emotional and social — and be able to explain how inactivity leads to each one.

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What Is a Sedentary Lifestyle?

Sedentary means sitting or lying down for extended periods with minimal energy expenditure. Examples include:

• Sitting at a desk all day
• Watching television for long periods
• Playing video games or scrolling social media
• Driving everywhere instead of walking or cycling

The Chief Medical Officer recommends that adults do at least 150 minutes of moderate-intensity activity per week (or 75 minutes of vigorous activity). Many people in the UK do not meet this target.

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Physical Consequences

1. Obesity

Mechanism	Detail
Positive energy balance	Energy intake (food) exceeds energy expenditure (activity), so excess energy is stored as fat
Reduced metabolic rate	Less muscle mass means the body burns fewer calories at rest
Cycle of inactivity	Being overweight makes activity more difficult, leading to even less exercise

Obesity increases the risk of many other conditions listed below.

2. Coronary Heart Disease (CHD)

A sedentary lifestyle increases the risk of CHD because:

• Cholesterol builds up in the coronary arteries (atherosclerosis)
• Blood pressure rises due to stiffer blood vessels and excess body weight
• The heart muscle weakens from lack of cardiovascular training
• Blood flow is restricted, increasing the risk of heart attack

3. Type 2 Diabetes

How Inactivity Causes Type 2 Diabetes	Detail
Insulin resistance	Without exercise, cells become less responsive to insulin
Weight gain	Excess body fat (especially around the abdomen) worsens insulin resistance
Blood sugar rises	The body cannot regulate blood glucose effectively

4. Hypertension (High Blood Pressure)

Inactivity leads to:

• Stiffer, less elastic blood vessels
• The heart working harder to pump blood
• Increased risk of stroke, heart attack and kidney damage

5. Depression and Poor Mental Health

How Inactivity Affects Mental Health	Detail
No serotonin boost	Without exercise, the body produces less serotonin, increasing the risk of depression
Social isolation	Sedentary people miss out on the social benefits of sport and exercise
Poor self-image	Weight gain and reduced fitness lower self-esteem
Poor sleep	Inactivity is linked to insomnia and poor sleep quality

6. Poor Posture

Sitting for long periods causes:

• Weakened core muscles — the muscles that support the spine lose tone
• Tight hip flexors — prolonged sitting shortens the hip flexor muscles
• Rounded shoulders — leaning forward over a desk or screen
• Back pain — poor posture leads to chronic lower back pain

7. Osteoporosis