According to the World Health Organization, physical inactivity is a serious health problem worldwide. It is a major cause of disability and deaths of around two million people in a year. Developed and developing countries are at higher risk of diseases caused due to lack of physical activity and sedentary lifestyle habits. Among these numbers, the number of children is also greater due to digitization and shift of children's taste from outdoor to computer games.
Physical inactivity has become a major public health concern. When it is accompanied by substance abuse and poor diet, the risk of chronic diseases doubles. Our body is made up of millions of cells and tissues and as we age, their functions decline as well. Thus, to increase life expectancy and promote the repair and growth of new cells and tissues, physical activeness is a must as it helps in regulating the essential hormones and slowing our ageing.
There are several diseases caused due to inactive lifestyle choices. Here is the list of diseases linked to physical inactivity.
1. Type 2 diabetes
Diabetes is an epidemic affecting around 100 million people worldwide. Physical activity helps to prevent or manage the risk of type 2 diabetes by 58%. Studies show that regular physical activity improves the glucose level in our body along with positively affecting lipid levels, blood pressure and quality of life. It is proved that the benefits of physical activities like walking, cycling and gymming improve insulin actions in a person. 
Physical activity is tremendously linked to mental wellbeing. On the other hand, poor mental health is the main cause of depression and anxiety in people followed by unemployment, low income and increased health risks. This is because mental health sufferers are less likely to visit physical healthcare centres for routine check-ups like weight and blood pressure and thus, their serious conditions get unidentified. Also, they are offered less guidance to stop smoking or drug abuse which are the risk factors for mental conditions. 
The imbalance in the energy we consume and the energy we burn is the main cause of obesity in people. The food we eat gives our body some amount of energy. That energy needs to be burnt up by doing some physical activities. When such activities do not take place, the energy starts converting into fat and gets deposited in our body. The increase of fats in our body often causes stroke and other diseases. A study shows that physical inactivity is the main culprit in abdominal obesity and a BMI increase. 
4. High blood pressure
According to a report, the prevalence of high blood pressure tends to increase by 60% by 2025 due to an unhealthy lifestyle of people. Physical activity is the primary prevention and treatment method for people with hypertension. It helps in the reduction of both diastolic and systolic blood pressure which further helps to lower down the blood pressure. 
5. Coronary heart disease
The three major risks of coronary heart disease are smoking, high cholesterol and high blood pressure. Adding up to it, physical inactivity is on top of the list, according to the World Health Organization. Inactive people pay less attention to utilize their body's energy gained by foods, which results in the deposition of excess fats in the body. The deposited fats obstruct the blood flow in the heart, causing several cardiovascular diseases like stroke. 
6. Breast cancer
The hormone 'estrogen' is very important for the growth and sexual development in females. High levels of estrogen can increase the risk of breast cancer in women. Physical inactivity is one of the main reasons for the imbalance in this sex hormone. A study related to breast cancer denotes that in physically active women, the chances of hormonal imbalance is very low due to weight loss compared to inactive women. 
7. Renal diseases
Exercise improves the overall metabolic functions of our body like insulin resistance, oxidative stress and blood pressure which are linked to the good renal functions and decrease in the risk of chronic kidney diseases. Lack of physical activity can increase the risk of conditions like diabetes, obesity and metabolic disorders. Therefore, to preserve the health of the kidneys and keep all other diseases at bay, physical activity is a must. 
Sleep and exercise cause positive effects on each other and are mandatory for good health. People who sleep for less than the recommended seven hours are prone to mental illnesses like insomnia or sleep deprivation. Physical activity regulates the natural biological clock of the body and decreases the symptoms of anxiety or depression, which improves the quality of sleep in a person. 
Bone-related diseases like osteoporosis cause significant mortality across the world due to lifestyle choices which greatly affect the health of people. Osteoporosis is a condition in which the bones become fragile and weak and the risk of fracture and other bone disorders increases. Physical activity strengthens the spine and hip which stimulate net bone formation along with improving the skeletal growth and preventing the risk of bone loss due to ageing and osteoporosis. 
10. Inflammatory diseases
Chronic inflammatory diseases like diabetes, stroke and metabolic syndrome are mainly caused due to lack of physical activity. Experts suggest that a minimum of 20 minutes of physical exercise daily stimulates the immune system to produce anti-inflammatory cellular response against the proteins that trigger inflammation in the body. Regular physical exercise can lower the mortality rates caused due to such inflammatory diseases.