Exercise as it relates to Disease/Lowering Cholesterol Levels: Exercise and Healthy Eating vs Drug Alternatives

Background to Cholesterol
Cholesterol is a fatty (lipid) substance that circulates through the blood in a particle form known as lipoproteins and is vital for numerous metabolic functions. There are two main types of lipoproteins found in the body: high-density lipoproteins (HDL) also known as “good cholesterol” and low-density lipoproteins (LDL) commonly referred to as “bad cholesterol." Cholesterol is made in the liver and is also found in all food products that derive from animals. Cholesterol in excess can cause many problems associated with the cardiovascular system.

What is classified as high cholesterol levels?
High cholesterol levels are defined as follows:
 * Total cholesterol greater than or equal to 5.5 mmol/L
 * HDL cholesterol less than 1.0 mmol/L for men and less than 1.3 mmol/L for women
 * LDL cholesterol greater than or equal to 3.5 mmol/L

Causes of high cholesterol levels

 * Lifestyle causes: poor diet/nutrition (especially diets high in saturated and trans fats), insufficient exercise, being overweight, smoking, alcohol consumption
 * Genetic/hereditary causes: high blood cholesterol levels can be linked to genetic predispositions and the genes for this can then also be inherited
 * Other diseases:hypertension, diabetes, liver diseases, thyroid problems, kidney diseases, and high levels of triglycerides can all contribute to elevated cholesterol levels

Health issues associated with high cholesterol levels
There are many problems that can potentially arise as a result of high cholesterol levels. Atherosclerosis(thickening of the artery wall) is the main complication associated with high cholesterol and this in turn results in other serious complications, these include:
 * Myocardial infraction: more commonly known as a heart attack, occurs when blood flow to part of your heart stops
 * Stroke: occurs when blood flow to the brain is reduced due to a blockage
 * Angina: refers to chest pain and arises due to disruptions in blood flow through the arteries

Treatments
The main goal of treatments is to decrease LDL levels as well as increase HDL levels and in turn decrease the chances of developing potentially fatal associated cardiovascular complications. Treatment usually involves a mixture of exercise, dietary changes and pharmaceutical interventions.

Statins
Statins are the most common and effective form of drug that is used to lower elevated cholesterol levels. Statins work to lower the levels of LDL cholesterol through blocking an important step in the process of manufacturing cholesterol in the liver. It should be known that taking statins do come with risk of side effects, however these risks are relatively uncommon and may go away as your body becomes used to the medication, the main side effects include muscle and joint pain/soreness/weakness and digestive problems (nausea, diarrhea, constipation).

Other forms of medication
Statins are usually the first option of drug used. However under some circumstances, other forms of medication may need to be used as an alternative. This may be due to the fact that your body may not tolerate the statin or simply because the drug is not working adequately. These other drugs may be used alone or in conjunction with one another to help lower cholesterol.
 * Ezetimibe: lowers LDL levels by blocking cholesterol absorption in the small intestine
 * Fibrates: lowers levels of triglycerides and increases levels of HDL, no effect in lowering LDL levels
 * Niacin (nicotinic acid): increases levels of HDL and therefore lowering level of LDL

Exercise
Non-medical interventions have always been the first preference when it comes to lowering cholesterol levels. Exercise has been shown to decrease cholesterol levels by means of losing or maintaining weight. In addition to this, exercise is a great preventative measure that can be taken, especially if there is history of cholesterol abnormalities within families. However, the convenience and speed at which medication acts becomes the more favourable approach, particularly when individuals have been diagnosed with severe elevated cholesterol levels, which under those circumstances, medication should definitely be the first means of treatment. Nevertheless, the combination of medication and lifestyle factors can be used in conjunction with one another to provide the best possible outcome. Current research has shown that regular exercise can reduce LDL cholesterol by up to 5-10% and HDL cholesterol can be raised between 3-6%. Regular exercise helps to lower cholesterol due to the following reasons:
 * Physical activity promotes enzyme activity to help move LDL from the blood to the liver to be converted into bile, which is then used in digestion or is excreted
 * Increase in lipoprotein size as smaller/dense lipoproteins have been shown to increase the risk of developing cardiovascular diseases

Recommendations
Exercise Diet
 * Mode: aerobic activities that involve large muscle groups e.g. jogging, walking, cycling
 * Intensity: 55-90% of maximum heart rate
 * Duration: 20–60 minutes
 * Frequency: 3–5 days per week (5-7 will provide the greatest results)