Coronary Artery Disease (CAD) or Coronary Heart Disease (CHD) is a medical condition in which plaque builds up inside the arteries which supply oxygen-rich blood to the heart muscle.
Fat, cholesterol, calcium and other substances present in the blood leads to the formation of plaque. Plaque reduces the oxygen-rich blood flow to the heart muscle by narrowing the arteries which can cause angina (chest pain) or a heart-attack.
CAD is a very common heart disease and a leading cause of death all over the world. There are various risk factors for this disease which are all interconnected but can be modified with exercising.
Smoking tobacco increases the risk of CAD. Smokers are at a greater risk for heart disease than non-smokers. With regular physical activity, smokers are likely to cut down or stop the habit. The risk of heart disease decreases within a year of smoking cessation along with regular exercise.
The risk of heart disease increases with an increase in blood pressure. Systolic BP>= 140 mmHg or Diastolic >=90 mmHg is a risk factor. During exercise, the heart muscle is forced to beat faster to keep up with the body’s oxygen demands. This makes it stronger. The blood vessels which supply oxygen-rich blood to the heart also become flexible and are better able to dilate (expand) enhancing blood vessel functioning and lowering the chances of hypertension. There is an approximate reduction of 10 mmHg in both, Systolic and Diastolic BP in people with mild to moderate hypertension, if they exercise regularly.
This refers to abnormalities in blood lipid and lipoprotein concentrations. CAD risk increases if low density lipoprotein (LDL), which is bad cholesterol, is greater than 130 mg/dl or High-Density Lipoprotein (HDL), which is good cholesterol, is less than 40 mg/dl or if total cholesterol is greater than 200 mg/dl. Exercise raises HDL and when combined with a nutritious low fat diet, it lowers the LDL.
Diabetes Mellitus (DM)
If your fasting blood glucose is greater than or equal to 100 mg/dl, you are at CAD risk. Exercising has insulin like effect which enhances the utilization of glucose even in the absence of sufficient insulin. Physical activity decreases insulin requirements for people with diabetes. Thus it improves insulin sensitivity and glucose utilization in the body in people with type 1 DM. Exercise enhances fat loss in people with type 2 DM along with improved insulin sensitivity and glucose utilization. Exercise also helps in burning excess fat and keeps a check on your weight. People with a healthy weight are less likely to develop diabetes.
Being overweight or obese has a direct relationship with all other risk factors of CAD. The risk is greater in people with a lot of fat on the abdomen. A waist circumference greater than 40 inches for men and greater than 35 inches for women or Body Mass Index (BMI) > 30 kg/m2 (Weight in kg divided by height in meter square) or Waist to Hip Ratio (WHR) >= 0.95 in men and >=0.86 in women represent obesity. Exercise helps in burning excess calories. With regular exercise, there is a reduction in overall body fat. Decreased abdominal fat reduces the risk factors for CAD; including dyslipidemia, type 2 DM and hypertension. A combination of diet and exercise is the only way to lose excess body fat and maintain a healthy weight.
People, who do not participate in a regular exercise program for at least 30 minutes or more on most days of the week, carry a risk of CAD. Sedentary lifestyle triggers other risk factors for CAD.