Exercise as it relates to Disease/Exercise prescription in obese hypertension patients

What Is Obesity?
Obesity can be defined as the accumulation of excess body fat. It is generally accepted that obese people are those with a BMI (Body Mass Index) of 30 or more and in 2008 it was estimated that the overall cost of obesity in Australia was $58.2 billion. People who are obese are predisposed to higher rates of premature death, cardiovascular disease, high blood pressure, type 2 diabetes, sleep apnoea, osteoarthritis, psychological problems and reproductive problems for women.

What is Hypertension?
Hypertension describes high blood pressure. Blood pressure describes the force exerted on the walls of arteries by blood as it travels around the body. It is expressed in the form of Systolic Blood Pressure (SBP), which is the pressure of blood in arteries as the heart beats, over Diastolic Blood Pressure (DBP), which is the pressure of blood in arteries as the heart relaxes, and is expressed in millimeters of mercury (mmHg). Hypertension is associated with coronary heart disease, stroke, heart failure, and chronic kidney disease and its major causes consist of obesity, insufficient physical activity, poor diet (high in salt) and excessive consumption of alcohol. In 2011-12 the Australian Health Survey found that 31.6% of Australians had hypertension.

Classifications of blood pressure and BMI are as follows:

Common Treatments
 Obesity: A combination of calorie restrictive diet and regular aerobic exercise has been shown to be effective.

 Hypertension:  The ultimate goal for the treatment of Hypertension is to reduce SBP to <140 mmHg. Once this has been achieved most people will also achieve DBP goal of <90 mmHg. Common treatments include: Antihypertensive drugs, Lifestyle Modifications such as; weight loss, diet(DASH diet), reducing alcohol intake and increasing physical activity and Surgery.

Obesity and Hypertension Combined
Obese individuals are 1.5 times more likely to develop hypertension than overweight people (BMI≥25 )and up to 2 times more likely than people with a BMI of <25. Approximately three-quarters of people diagnosed with hypertension are obese. Hypertension in obese patients has been found to be harder to treat than cases in non-obese populations.

Exercise Prescription
Exercise, in conjunction with lifestyle modifications, should be the starting point for treatment of obesity related hypertension. Intervention programs that cater for obesity-hypertension will combine diet,behavioural adjustments (quit smoking) and physical activity with long term goals of improving health and healthy habits.

Benefits
Benefits of regular physical activity for obese hypertension sufferers include:
 * Weight loss.
 * Reduced blood pressure.
 * Post exercise Hypotension(PEH) can be provoked for up to six hours post-exercise.
 * Lowers cardiovascular risk factors.
 * Boosts antihypertensive drug effectiveness.

Considerations
Obese people have a greater level of stress on the heart when exercising, which risks adverse cardiac events. This needs to be taken into account when exercising, with moderate intensity exercise designed to expend calories and maintain cardiovascular fitness being the main goal. Excess weight places extra burden on joints. This can be catered for through non-weight bearing exercises such as swimming or cycling. Resistance training has similar effects to aerobic exercise in reductions in blood pressure.

Recommendations
Current guidelines recommend 150–300 minutes of physical activity per week and focus on weight loss and the prevention of weight gain. Moderate to high-intensity aerobic exercise for a minimum of 30 minutes a day is recommended. This does not have to be in one burst. It can be done in shorter segment to allow for busy lifestyles as long as it adds up to a minimum of 30 minutes. Activity points systems (APS) are a useful way to quantify physical activity. APS's take into account individual factors and can be put into action with the hep of your G.P. It is vitally important to take into account greater stresses on the heart and the fear of physical responses to exercise. Exercise programs should be developed with long term adherence as a primary consideration. If any issues occur, outside of normal responses to exercise, then exercise should be stopped and a visit to your G.P. may be necessary to review your exercise plan.