Exercise as it relates to Disease/Combating Dyslipidaemia: Exercise vs Pharmaceutical intervention
Cholesterol and triglycerides are widely grouped together as Lipids or fats and are an important component to the normal functioning of the body. When blood lipid (fats) concentrations become either too high or too low, this condition is described as Dyslipidaemia . The most common forms of Dyslipidaemia are high levels of Low density Lipoprotein (LDL) or “bad” cholesterol, Low levels of High density Lipoproteins (HDL) or “good” cholesterol and high levels of triglycerides. According to the 2011-2012 Australian health survey, 63.2% of the Australian population over the age of 18 have some sort of lipid disorder, Furthermore it is estimated that 5.6 million Australian adults have unmanaged high blood cholesterol and of these adults only 1 in 10 are consciously aware of this fact:.
Dyslipidaemia is a condition that is caused by many different factors. In developed countries the most prevalent cause of Dyslipidaemia is the combination of sedentary lifestyle and excessive consumption of fatty foods. Genetic abnormalities (inherited), certain forms of medication and the presence of other diseases can also induce abnormal lipid concentrations in the blood, other lifestyle factors like obesity, smoking, and alcoholism are also common contributors.
The target Blood lipid concentrations for health are:
- Triglycerides - Between 10-150 Mg/dL
- Total cholesterol - Less than 200 Mg/dL
- HDL - Between 40-60 Mg/dL
- LDL - Between 10-150 Mg/dL
Blood lipid concentrations above or below these norms, if not managed can lead to developing serious health issues (diabetes, atherosclerosis, strokes, heart disease etc).
There are two main methods of combating dyslipidaemia, one being exercise and lifestyle, the other being the use of pharmaceutical drugs. The aim of these methods is to return the blood lipid concentration back to the recommended ranges.
Drug intervention in combating dyslipidaemia provides patients with a proven and efficient method of lowering their blood lipid concentrations, drug therapy although expensive has been proven to lower blood LDL levels by about 30-40%. There are many different drugs on the market today for treating dyslipidaemia, below is a summary of the main classes of drugs currently in use:
|Statins- (e.g atorvastatin, simvastatin, and rosuvastatin)||Inhibit cholesterol production,thus ↓ blood LDL levels, ↓ triglycerides levels and also ↑ HDL activity||Myopathy, insulin resistance,liver damage and digestive problems|
|Bile acids- (e.g cholestyramine and colestipol)||increase LDL uptake, thus ↓ blood LDL levels, adversely ↑ blood triglyceride levels||Gastrointestinal irritation, constipation, Bloating and indigestion|
|Nicotinic acid- (e.g Niacin)||Inhibit lipolysis, ↓ blood triglyceride levels, ↓ LDL levels and ↑ HDL levels||Hepatotoxicity, flushing,skin rashes, indigestion, and rarer cases of nausea, vomiting and diarrhea.|
|Fibric acid deriviatives- (e.g clofibrate, gemfibrozil and fenofibrate)||↓ both blood triglyceride and LDL levels, also ↑ blood HDL levels (mechanism unclear)||Gastrointestinal irritation, rarer cases of rashes, fatigue, headaches, and muscle pain|
|Ezetimibe- (e.g Zetia, Ezetol)||inhibit luminal uptake of cholesterol, ↓ LDL concentrations in the blood, ↓ blood triglycerride levels||allergic reactions (rare), skeletal abnormalities (with high doses)|
The drugs above are usually combined to greater affect, caution need to be taken when administrating these drugs to children, pregnant and (or) nursing mothers.
Exercise in combination with lifestyle and diet intervention is considered the primary method of combating dyslipidaemia, for many individuals this approach has proven to be safer and much more effective in lowering blood cholesterol concentrations. Exercise and lifestyle modification target the following:
- Lowering total body fat (↓ triglyceride levels).
- Increase LDL utilization by muscles (↓ LDL levels).
- Increase HDL (good cholesterol) activity and decrease consumption of fats, sugars and syrups.
Exercise offers many positive benefits to lowering blood lipid concentrations, however it also poses many potential risks,in particularly for patients whose blood lipid concentrations are > 250 (Mg/dL). In this case exercise may in fact be detrimental as it can induce potentially fatal conditions such as strokes or heart attacks.
Lifestyle therapies that combine diet and exercise interventions are cheaper, safer and more effective in combating dyslipidaemia, for these reasons it is often the preferred method of intervention.
Diet- Aims is to reduce cholesterol levels, this can be done by:
- reducing consumption of animal fat, replace saturated fat with mono or poly saturated fat, reduce overall energy intake, increase the consumption of fruits, veges, plant Sterols and Stenols etc.
Exercise- Aims to burn excess triglyceride (loose weight), this is done by:
- A high amount of vigorous intensity (65%-80% of vo2 max) exercise on a regular basis (equivalent to 32km of jogging weekly), cutting out sedentary habits, method like walking to the shops, work, or school and general ↑ in physical activity. Dyslipidaemia patients should always consult a health care professional before commencing an exercise program.
Below are some further readings:
- G.H Williams, William F. Young, 2013, The Endocrine Health Society, Hormones Health Network, viewed 20/09/2013, http://www.hormone.org/diseases-and-conditions/heart-health-and-metabolism/dyslipidemia
- Manrigue, C, Rosenzweig, J, Umpierrez, G, 2009, ‘Diabetes, Dyslipidemia, and Heart Protection’, The Journal of Clinical Endocrinology & Metabolism, vol. 94, no. 10, viewed 20 September 2013, http://jcem.endojournals.org/content/94/1/0.2.full.pdf+html.
- Australian bureau of statistics, 2013, ‘Dyslipidaemia’ Australian Health Survey: Biomedical Results for Chronic Diseases, 2011-12, viewed 22 September 2013, <http://www.abs.gov.au/ausstats/abs@.nsf/Lookup/DB595DB607116672CA257BBB0012186D?opendocument
- Heart foundation, 2013, Internet, viewed 22 September 2013 <http://www.heartfoundation.org.au/news-media/Media-Releases-2013/Pages/australians-high-cholesterol-survey.aspx>
- Goldberg, A 2008, ‘Dyslipidaemia (Hyperlipidaemia)’, Endocrine and Metabolic Disorders, Viewed 24 September 2013,<http://www.merckmanuals.com/professional/endocrine_and_metabolic_disorders/lipid_disorders/dyslipidemia.html#v990115>
- Goodman, Gilman, ‘Drug Therapy for Hypercholesterolemia and Dyslipidemia’, Brunton, L ‘The Pharmacological Basis of Therapeutics’,.. 12, viewed 24 September 2013, http://www.accessmedicine.com.ezproxy1.canberra.edu.au/content.aspx?aID=16683537
- MedlinePlus, 2012, National institute of health, online, viewed 20/09/2013, http://www.nlm.nih.gov/medlineplus/ency/article/000403.htm
- Goodman, Gilman, ‘Drug Therapy for Hypercholesterolemia and Dyslipidemia’, Brunton, L ‘The Pharmacological Basis of Therapeutics’,.. 12, viewed 22 October 2013, http://www.accessmedicine.com.content.aspx?aID=16669469
- K. Varady, P. Jones, 2005, ‘Combination diet and exercise interventions for the treatment of dyslipidemia: an effective preliminary strategy to lower cholesterol levels?’, vol. 185, no. 8, 1829-1885xx-xx, viewed 22/10/13, The journal of nutrition.
- M. Carrington, S. Stewart, 2011, Australian cholesterol crossroads: an analysis of 199,331 GP patient records, CRE000484, Heart & diabetes institute, viewed 22/10/2013.
- Slentz CA, Duscha BD, Johnson JL, et al. Effects of the Amount of Exercise on Body Weight, Body Composition, and Measures of Central Obesity: STRRIDE—A Randomized Controlled Study. Arch Intern Med. 2004;164(1):31-39. doi:10.1001/archinte.164.1.31