Exercise and Cholesterol

Doctors love prescribing stuff for high cholesterol, but the best way of reducing your levels of bad cholesterol is by looking at your diet and activity levels.
Ask any British citizen over the age of 50 years of age, and more than likely he or she will have a concern about cholesterol. Many people do not understand the interaction between exercise and cholesterol, so we will try and sort this problem out.

Why is high cholesterol a problem? The main risk associated with high cholesterol is coronary heart disease (CHD). This is caused by blood vessels becoming narrowed with fatty deposits called plaques, which cholesterol contributes to. The narrowed blood vessels reduce blood flow to the heart. This can result in angina (chest pain) or, if the vessel is blocked completely, a heart attack. For more information see the BUPA factsheets on Angina and Heart attack. High cholesterol can also increase the risk of other conditions, depending on which blood vessels are narrowed or blocked. These include stroke if the blood supply to part of the brain is reduced. For more information see the BUPA factsheet on Stroke. There is also a risk of peripheral vascular disease. This is caused by narrowed blood vessels in the limbs, particularly the legs. It may result in leg pain, ulcers, infections and eventually gangrene.

Types of cholesterol Cholesterol is transported around the body in the blood attached to a protein. This fat-protein combination is called a lipoprotein. Lipoproteins can be high density (HDL), low density (LDL) or very low density (VLDL), depending on how much protein there is in relation to fat.
LDL (low density lipoprotein) About 70% of cholesterol is transported as LDL. This is mostly fat and not much protein. LDL causes cholesterol to be deposited in the arteries. High levels of LDL are associated with an increased risk of heart disease. LDL is sometimes referred to as "bad cholesterol".

HDL (high density lipoprotein) About 20% of cholesterol is transported as HDL, which is mostly protein and not much fat.
HDL actually helps prevent cholesterol building up in the arteries. Low levels of HDL are associated with an increased risk of heart disease. HDL is sometimes referred to as "good cholesterol". Women tend to have a higher HDL cholesterol level than men.
If the total cholesterol level is too high, this is one risk factor for health problems. However, it's important to consider the relative amounts of HDL and LDL. A high level of HDL and a low level of LDL is desirable.

Triglycerides Triglycerides are a different type of fat, which mostly come from fats in food. Calories that are eaten and not used immediately are converted into triglycerides and transported to fat cells for storage. Although most triglycerides are stored in fat tissue, low levels are also found in the blood. They are carried in the blood as very low density lipoproteins (VLDL).
A raised level of blood triglycerides together with high LDL can increase the risk of heart disease.

What causes high cholesterol? There are several factors that may contribute to high blood cholesterol: a diet that's high in saturated fat and, less so, high in cholesterol (see below) lack of exercise may increase LDL ("bad") cholesterol and decrease HDL ("good") cholesterol family history - people are at a higher risk of high cholesterol if they have a direct male relative aged under 55 or female relative aged under 65 affected by coronary heart disease being overweight, which may increase LDL ("bad") cholesterol and decrease HDL ("good") cholesterol age and sex - cholesterol generally rises slightly with increasing age, and men are more likely to be affected than women drinking alcohol excessively Rarely, high cholesterol can be caused by a condition that runs in the family called a lipid disorder (familial hypercholesterolaemia).

Other health conditions such as poorly controlled diabetes, certain kidney and liver diseases and an underactive thyroid gland may also cause cholesterol levels to rise. Some medicines such as beta-blockers, steroids or thiazides (a type of diuretic) may also affect blood lipid levels.
Prevailing evidence supports the concept that physical activity can help slow the progression of Coronary Heart Disease (CHD). Reducing actual Cholesterol through exercise, can be quite labour intensive. However it is important to remember that exercise also greatly increases the functional size of blood vessels, therefore reducing any risk of the cholesterol causing a ‘blockage’. This increase in size also reduce blood pressure.
When individuals accumulate a sufficient weekly volume of exercise they can lower both total cholesterol and LDL-cholesterol and increase HDL-cholesterol (the “good” cholesterol). Exercise itself does not “burn off” cholesterol like it can with fat tissue. However, when exercise is of sufficient volume, for example, an adequate weekly frequency and duration, it can significantly reduce triglycerides and stimulate several metabolic enzyme systems in the muscles and liver to convert some of the cholesterol to a more favourable form, such as HDL-cholesterol. Reducing triglycerides decreases triglyceride-rich particles that are known to promote the growth of fatty deposits on artery walls.
A major exercise effect on blood cholesterol levels appears to be an increase in HDL Cholesterol (Good Cholesterol) as a result of aerobic training. This change is very important because HDL-C is the most critical determinant of CHD. Unfortunately, research has not really told us, exactly how much exercise is needed to raise HDL-C. Until specific recommendations based on further research are developed, we recommend following ACSM guidelines for frequency, intensity and duration of exercise because these are the most current and scientifically-documented recommendations. The ACSM states that physical activity should be undertaken three to five times each week for 20 to 60 minutes at a time. The activity should involve the large muscle groups (e.g., walking, running, cycling, and swimming). The level of intensity (target heart rate) for this physical activity should be at least 55% to 65% of your maximum heart rate. (You can estimate your maximum heart rate by subtracting your age from 220.)

Some more guidelines include: · If you do have a less-than-desirable cholesterol level, or your doctor has told you have a cholesterol disorder, have your physician establish your cardiovascular health status before engaging in a vigorous exercise program. Your physician may elect to perform additional blood tests (e.g., C-reactive protein)and/or a graded exercise test with an ECG (treadmill stress test) on you first.
· Choose dynamic forms of exercise that tend to last at least 20 to 30 minutes and are performed at moderate intensities. Moderate exercise intensities would be an approximate effort of four to seven, on a scale of one to ten with ten being near maximal exercise.
· In general, for exercise to significantly lower cholesterol levels, a relatively high volume of exercise is recommended (e.g. 1,500 kcal or more per week). In 12 to 16 weeks this volume of exercise can reduce total cholesterol by 10 to 20 percent. Fifteen hundred calories expended during exercise is equivalent to about three to four hours per week for the average unfit person performing moderate intensity walking, swimming, walk-jogging or cycling.

It has been proven that aerobic exercise in conjunction with a sensible diet, is by far the most effective way to reduce cholesterol and decrease the risk of cardio vascular disease. Remember that exercise not only reduces bad cholesterol and increases good cholesterol, it also increase the diameter or blood vessels, meaning that blood flow is less restricted.

Disclaimer: Exercise and diet at your own risk. Consult a Doctor before exercising or dieting.