# Exercise as it relates to Disease/Pills vs exercise: reducing blood pressure in hypertension
## Background to hypertension

Blood pressure is a measurement of the force of the blood against the walls of arteries as the heart pumps blood through the body It is measured in millimetres of mercury (mmHg) and is presented as systolic pressure (the pressure exerted on the blood vessels by the heart when it contracts) over diastolic pressure (the pressure on the blood vessels when the heart relaxes and dilates). A normal healthy blood pressure reading is 120mmHg systolic/80mmHg diastolic, however when systolic blood pressure is ≥140 mmHg and diastolic blood pressure is ≥90 mmHg then it is categorised as hypertension

## Causes of hypertension

The exact causes of hypertension are usually unknown however there are lifestyle and physiological factors that are highly associated with the condition, these include:
   * Lifestyle/Dietary Causes: Being overweight, alcohol consumption, lack of physical activity, poor nutrition (most notably low fruit & vegetable intake and a higher consumption of salts and saturated fats), Stress
   * Physiological/Disease Causes: Diabetes, medications (such as birth control), Chronic Kidney Disease, adrenal and thyroid problems/tumors

## Health issues associated with hypertension

There are many potential health complications that hypertension can cause particularly in persistent and/or untreated hypertension, these include:
   * Heart complications: Heart attack, cardiovascular disease, enlargement of left ventricle, atrial fibrillation
   * Artery complications: Arteriosclerosis, aneurysm, Coronary Artery Disease
   * Kidney complications: Kidney scarring, kidney artery aneurysm, chronic kidney disease
   * Brain complications: Stroke, Transient Ischemic Attack (TIA)

## Treatments

The ultimate goal behind treatment is to reduce blood pressure and as a result protect the body from the negative consequences associated with high blood pressure. Treatment options often require the combination of drug therapy and lifestyle factors such as diet modifications and physical activity.

### Medication

Anti-hypertensive medications are a popular form of treatment in patients suffering from hypertension and are advantageous over exercise in terms of:
   * Convenience (especially time)
   * The speed at which they act (fast acting)
There are a number of different types of hypertensive medications and it is not uncommon for patients suffering from hypertension to require the use of a combination of medications. Different categories of medications reduce blood pressure in different ways, the 4 major methods of reducing blood pressure include:
    1. Preventing blood vessels from constricting – e.g. Angiotensin Converting Enzyme (ACE) inhibitors
    2. Reducing heart rate – e.g. Beta blockers
    3. Allowing blood vessels to relax – e.g. Vasodilators and Calcium channel blockers
    4. Decreasing blood volume – e.g. Diuretics
Although there is plenty of evidence to support the use of anti hypertensive medication, there are also a number of disadvantages associated with there use, these include,
   * Unwanted side effects e.g. dizziness, weakness, headaches and diarrhea
   * Cost
   * Limited effectiveness- most hypertensive patients require multiple medications to gain any worthwhile benefit.

### Exercise

Non- pharmacological approaches for reducing hypertension have long been preferred as the primary form of treatment. Of these treatments, physical activity is considered to be one of the most beneficial interventions and can be used in conjunction with anti hypertensive medications to provide further reductions. Exersise as a form of treatment is advantageous over medication in terms of:
   * Promoting a whole body response - unlike medications, exercise will also positively effect other body systems
   * Affordability
   * providing a variety of physical, mental and social benefits
Current research suggests that regular physical activity can help reduce blood pressure both directly and indirectly in a number of ways, these include:
    • Directly: by decreasing systolic blood pressure, on average between 5 – 25mmHg
    • Directly: by decreasing diastolic blood pressure, on average between 3 – 25mmHg$^{[8]}$
    • Indirectly: by encouraging weight loss and improving cardiovascular health.
In spite of the obvious benefits of exercise as a treatment, there are also some associated disadvantages some of which include:
   * Time - both the time required to exercise daily as well as the time it takes to see reductions in blood pressure
   * Difficulty for those with limited mobility or those suffering from chronic pain.

## Recommendations

Regular exercise has the potential to benefit all forms of hypertension. It can be used in combination with medications to enhance blood pressure reduction in those suffering severe hypertension, or as a primary source of treatment in mild hypertension and even as a preventative measure for those at risk of developing hypertension. Current exercise recommendations for reducing blood pressure include:
   * Cardiorespiratory exercise e.g. walking, cycling or jogging
   * Minimum 3 days per week - However higher frequencies generally result in greater reductions$^{[13]}$
   * 20 - 60 min per session$^{[13]}$
   * At 40%-70% maximum effort$^{[13]}$
Contrary to popular belief Resistance training does not make hypertension worse. However there is a lack of evidence to show its effectiveness in reducing high blood pressure and therefore cardiovascular training should make up a majority of a hypertensive patients exercise program.
Although regular exercise is well documented as an effective form of reducing blood pressure, precautions should still be made in order to best maintain the health of the individual. Such precautions and considerations include:
   * Resting Blood pressure: Exercise should be postponed in poorly maintained blood pressure e.g. a resting blood pressure reading >180mmHg systolic or >110mmHg diastolic$^{[15]}$
   * Medications: Be aware of the effect of medications on the body e.g. decreases thermoregulation capacity$^{[15]}$
   * Exercise blood pressure: Cessation of exercise if blood pressure rises above 250mmHg systolic or 115mmHg diastolic$^{[15]}$

## Further reading

Further reading can be found at:
AusDiab Report-Department of Health and Ageing
Heart foundation guide to management of hypertension

## Reference List

* ↑ Medline Plus (2012) Hypertension . [online] Available at: www.nim.nih.gov/medlineplus/ency/article/000468.htm [Accessed: 19 Oct 2012].
* ↑ World-heart-federation.org (2012) Hypertension . [online] Available at: www.world-heart-federation.org/cardiovascular-disease-risk-factors/hypertension/ [Accessed: 20 Oct 2012].
* ↑ Medicalnewstoday.com (2009) What Is Hypertension? What Causes Hypertension?. [online] Available at: www.medicalnewstoday.com/articles/150109.php [Accessed: 20 Oct 2012].
* ↑ Mayo Foundation for Medical Education and Research (2012) High blood pressure (hypertension). [online] Available at: www.mayoclinic.com/health/high-blood-pressure/H100062 [Accessed: 19 Oct 2012].
* ↑ Medications for treating hypertension, 2009, Harvard Health Publications, Harvard Medical School, viewed 20/10/2012 http://www.health.harvard.edu/newsletters/Harvard_Womens_Health_Watch/2009/August/Medications-for-treating-hypertension
* ↑ HAGBERG, J. M., PARK, J. J. & BROWN, M. D. 2000. The role of exercise training in the treatment of hypertension: an update. / Le role de l'entrainement dans le traitement de l'hypertension: mise a jour. Sports Medicine, 30, 193-206.
* ↑ WARBURTON, D. E. R., NICOL, C. W. & BREDIN, S. S. D. 2006. Health benefits of physical activity: the evidence. Canadian medical association journal, 174, 801-809.
* ↑ WALLACE, J. P. 2003. Exercise in hypertension: a clinical review. Sports Medicine, 33, 585-598.
* ↑ NETER, J. E., STAM, B. E., KOK, F. J., GROBBEE, D. E. & GELEIJNSE, J. M. 2003. Influence of weight reduction on blood pressure a meta-analysis of randomized controlled trials. Hypertension, 42, 878-884.
* ↑ FAGARD, R. H. 2001. Exercise characteristics and the blood pressure response to dynamic physical training. Medicine and Science in Sports and Exercise, 33, 484-492.
* ↑ CLÉROUX, J., FELDMAN, R. D. & PETRELLA, R. J. 1999. Lifestyle modifications to prevent and control hypertension. 4. Recommendations on physical exercise training. Canadian Hypertension Society, Canadian Coalition for high blood pressure Prevention and Control, Laboratory Centre for Disease Control at Health Canada, Heart and Stroke Foundation of Canada. CMAJ: Canadian Medical Association Journal, 160, S21.
* ↑ APPEL, L. J. 2003. Lifestyle Modification as a Means to Prevent and Treat High Blood Pressure. Journal of the American Society of Nephrology, 14, S99-S102.
* ↑ WALLACE, J. P. 2003. Exercise in hypertension: a clinical review. Sports Medicine, 33, 585-598.
* ↑ FAGARD, R. H. 2006. EXERCISE IS GOOD FOR YOUR BLOOD PRESSURE: EFFECTS OF ENDURANCE TRAINING AND RESISTANCE TRAINING. Clinical & Experimental Pharmacology & Physiology, 33, 853-856.
* ↑ SHARMAN, J. E. & STOWASSER, M. 2009. Australian association for exercise and sports science position statement on exercise and hypertension. Journal of Science and Medicine in Sport, 12, 252-257.