What I want to do in this article is cover high blood pressure, known as hypertension, in relation to exercise. This is a very common condition that is often symptomless but can have a huge effect on a person’s life. In some cases, hypertension will also determine what exercise a person can do. Here I will cover what hypertension is, what causes it, signs and symptoms, diagnosis, health issues, prevalence, effects on cardiovascular exercise, effects on resistance exercise and medications for the disease. I hope that this article gives a well-rounded insight into the disease and is useful either for yourself or someone you know. If you do know someone who suffers from the disease and is thinking about exercise, then this article may prove useful.
What Is Hypertension?
Hypertension, or high blood pressure, is a chronic condition where the person suffers from a consistently higher blood pressure than normal. Blood pressure is monitored by measuring the force of the blood on the artery walls as it flows through them. This force is taken in two measurements. The first is systolic blood pressure (SBP). This is the maximum pressure of the blood on the artery wall during one heartbeat. The second is diastolic blood pressure (DBP). This is the maximum pressure of the blood on the artery wall between two heartbeats as the heart fills back up with blood. In short, if the arteries lose their elasticity and become more rigid, blood flow is hindered causing both the SBP and the DBP to become elevated.
There are two forms of hypertension; primary hypertension and secondary hypertension. Primary hypertension has no proven cause and is thought to be induced by genetic and hereditary factors. Having said this, poor lifestyle choices are more likely to trigger primary hypertension. A genetic response to salt can also aid in developing primary hypertension. Secondary hypertension is not as common but will often occur due to underlying medical conditions. These may include kidney disease, steroid use, thyroid issues, sleep apnea and tumours.
What Causes Hypertension?
There are four key mechanisms that occur in the body that may contribute to high blood pressure:
Cardiac output – the volume of blood pumped out of the heart every minute.
Peripheral resistance – the resistance and physical composition of the arteries.
Renin-angiotensin-aldosterone (RAA) system – the signalling pathway that regulates the body’s blood pressure.
Autonomic nervous system – the system responsible for unconscious messaging that regulates the body, inclusive of blood pressure and heart rate.
We can divide the contributing factors of high blood pressure into two separate parts, those that are modifiable (often lifestyle choices) and those that are non-modifiable.
MODIFIABLE
Smoking, Drug & Alcohol Use
Physical Inactivity
Poor Diet
High Cholesterol
Obesity
Stress & Mental Health
NON-MODIFIABLE
Age
Ethnicity
Genetics
Gender
What Are The Signs And Symptoms?
The majority of people who suffer from hypertension may not even be aware of it, as the disease often doesn’t display and obvious signs or symptoms. As such, it is hard to definitively quantify just how many people suffer from the disease. This is why hypertension is referred to as the ‘silent killer’, especially due to the slow rate of damage that the condition can cause to the smaller vessels of the eyes and nephrons of the kidneys. Common symptoms of hypertension may include:
Headaches – a sign of hypertension or the result of a hypertensive attack or episode. Some medical professionals have hypothesised that it may be due to dehydration and salt intake increasing pressure within the cranial cavity.
Sight Problems – acute hypertension can cause disruption of the blood-retinal barriers.
Nose Bleeds – there’s no clear evidence here, but hypertension does weaken blood vessels and could make it more likely that hard impact and nasal exhalation can rupture vessels.
Dizziness – this can be a side effect of some blood pressure medications, but not generally cause by hypertension itself.
Flushed Appearance – occurs due to stress, exposure to heat or alcohol consumption. These can raise blood pressure temporarily.
Difficulty Breathing – can occur due to the heart having trouble pushing blood flow through the lungs.
This all sounds rather drastic and are often symptoms in those with high blood pressure. Younger, regularly active individuals may experience these symptoms to varying degrees, but rarely means the person is in any immediate danger.
How Is Blood Pressure Diagnosed?
Blood pressure is measured in millimetres of mercury (mmHg). If you are worried about high blood pressure, you should be officially diagnosed by your doctor, not by testing yourself at home. Your blood pressure will be measured using a sphygmomanometer and a stethoscope (an older and more uncommon method) or an electronic blood pressure monitor (this is more commonly used in modern surgeries). The result of the test is given in two numerical readings, one place on top of the other and separated by a line. The top number is your SBP and the bottom in your DBP. The optimal blood pressure reading in healthy individuals will read 120/80 mmHg.
Hypertension diagnosis can be sub-classified into different stages based on the severity of the condition. Bear in mind that having a higher SBP creates a larger force on the artery wall. This will mean the heart has to work harder. As a result, hypertension can be a precursor to cardiovascular diseases. It is estimated that in England alone, 1 in 4 adults are hypertensive, with some suggesting that up to 40% of the adult population have the disease. The table below shows the different stages of hypertension. It is estimated that 5.5 million people in the UK suffer from hypertension and don’t even know. For every 10 people diagnosed with hypertension, 7 are undiagnosed and remain untreated.
Low <100/<60
Optimal 100-120/60-80
Normal 121-129/80-84
Pre-Hypertension 130-139/85-89
Stage 1 Hypertension 140-159/90-99
Stage 2 Hypertension 160-179/100-109
Stage 3 Hypertension >180/>110
What Health Issues Are Caused By Hypertension
Perhaps two of the main risk factors associated with hypertension are atherosclerosis (the narrowing of the arteries) and arteriosclerosis (the hardening of the arteries). This is because both conditions decrease the diameter of the blood vessel and its capacity to expand. During exercise, both of these conditions may raise blood pressure. If hypertension is allowed to progress, it can lead to some serious health issues. The idea of the list of health problems below aren’t listed to scare you, but to educate and make you aware of complications of high blood pressure. Use these as motivation to commit to healthy eating and an active lifestyle. Let’s have a look at the health risks associated with hypertension:
Arteriosclerosis – the arteries that carry oxygen and nutrients from the heart to the rest of the body become thicker and stiffer. This results in less blood being able to be transported.
Atherosclerosis – the thickening, or hardening, or the arteries caused by a build-up of plaque in the lining of the artery.
Stroke – a life-threatening condition that happens when the blood supply to part of the brain is cut off.
Transient Ischaemic Attack (TIA) – a condition where the blood supply to the brain is temporarily disrupted.
Kidney Failure – occurs when the kidneys are unable to filter waste products from the bloodstream.
Retinopathy – blockage of major retinal vessels in the eye.
Heart Failure – caused by thickening or stiffening of the heart walls as well as the narrowing and constriction of blood vessels.
Peripheral Artery Disease (PAD) – caused by atherosclerosis, where blood vessels leading to the legs and feet become narrow and hard, reducing blood flow.
So Just How Bad Is Hypertension?
It may be that you’ve only just started thinking about the possibility of high blood pressure. Maybe you’re here out of interest. Either way, hypertension as a disease has a huge impact globally. As I reside in the UK, I will be focusing on some key data relating to those living in UK. Sitting comfortably, get ready:
High blood pressure is the third biggest risk factor for all diseases in the UK following smoking and poor diet.
Around 1 in 3 adults suffer from high blood pressure. In England alone, an estimated 31% of men and 26% of women have hypertension.
Around half the people with high blood pressure are not even diagnosed or receiving treatment.
In England alone, there are more than five million people that are undiagnosed.
Hypertension rarely has any visible or physical symptoms. The only was to find out is to have your blood pressure measured.
High blood pressure costs the NHS over £2.1 billion every year and is responsible for around 75,000 deaths annually.
Hypertension accounts for 12% of all GP appointments in England.
High Blood Pressure And Cardiovascular Exercise
Those with hypertension should conduct cardiovascular training with the aim of decreasing blood pressure in the long term. Alongside this an increase in VO2 max, calorie expenditure and peak work rate should be taken into consideration. Following sustained periods of low to moderate intensity exercise, the body will experience an acute reduction in blood pressure that can last up to 12 hours. For those with hypertension committing to a regular plan of cardiovascular exercise, there are a few variables to consider and apply:
Frequency – 5-7 sessions a week is advisable.
Intensity – use a Rate of Perceived Exertion between 3-5.
Time – start with sessions of 30 minutes, working up to 60 minutes. This is generally regarded as safe.
Type – large muscle groups and rhythmic movements are suitable. Exercise such as cycling, walking and activities of daily living, such as gardening, are safe for hypertensives.
High Blood Pressure and Resistance Training
Those with hypertension should base their resistance training around low-resistance and high repetition work. This type of training should focus on endurance in the muscle rather than strength and power. A programme of higher loads, especially to failure, are best avoided. Circuit training is also recommended as a suitable mode of resistance training for hypertensives. Positives outcomes from this training also include increases in bone mass and the strength of connective tissue. For those with hypertension committing to a regular plan of resistance training, there are a few variables to consider and apply:
Frequency – 2-3 sessions a week is advisable.
Intensity – 12-15 repetitions of around 60% 1RM in given exercise.
Time – no longer than 30 minutes is recommended.
Type – resistance machines, free weights, circuit training, isotonic exercises only. In some cases, overhead and decline movements should be avoided.
Lifestyle Adjustments to Reduce High Blood Pressure
If you have been diagnosed with hypertension or want to reduce your risk of developing high blood pressure, there are several lifestyle changes that you can implement:
Reduce body fat to a healthy range.
Eat a good variety of fruit and vegetables every day.
Eat more foods that contain a good source of potassium and calcium as these can be lost due to hypertensive medications.
Avoid foods, especially processed, that contain high levels of trans fats.
Dramatically cut alcohol intake, the more the better.
Exercise for 30 minutes every day.
Keep salt intake below 6g per day.
Is My Hypertension Medication A Problem?
There are lots of different medications used to help treat and manage high blood pressure. It is vitally important that you understand the side effects of these and how they might potentially affect the way you exercise. Here is a list of medications and how they may change how you spend your time in the gym:
LOSARTAN (Class: Angiotensin II Antagonists) Function: to block the receptor of the Angiotensin II protein, preventing it from raising blood pressure by mediating vasodilation that would otherwise activate vasoconstriction. Side effects: Raised potassium, Joint or muscle pain, Dizziness, Mild hypotension. Other common Angiotensin II Antagonists: Irbesartan, Candesartan. Exercise relevance: Postural hypotension (avoid fast postural changes and sudden standstill), Dizziness.
HYDROCHLOROTHIAZIDE (Class: Thiazides - Diuretics) Function: Vasodilates blood vessels. Increases sodium and water output (diuresis) to reduce blood volume. Side effects: GI disturbance, Electrolyte imbalance, Impotence, Postural hypertension, Gout, Leg cramps, Dizziness, Dehydration, Aching legs. Other common Thiazides - Diuretics: Bendrofluazide. Exercise relevance: Dehydration - encourage adequate fluid intake, Postural Hypotension, Dizziness.
AMILORIDE (Class: Potassium-Sparing Diuretics) Function: to retain potassium and is a weak diuretic. Used in combination with Thiazide drugs. Side Effects: GI discomfort, Leg cramps, Dehydration, Nausea, Headache, Dizziness, Aching legs. Exercise relevance: Dehydration - encourage adequate fluid intake, Postural Hypotension, Dizziness.
METOPROLOL (Class: Beta Blockers) Function: Blocks beta receptors of the heart, which causes reduced speed and force contraction of the heart (cardiac output). Side effects: Bradycardia, Hypotension, Heart failure(rare), Fatigue, GI disturbance, Sleep disturbances, rash, Cold feet and hands, Urinary incontinence. Other common Beta Blockers: Atenolol, Acebutolol Exercise relevance: Decreased resting heart rate, Suppressed heart rate response to exercise, Reduced exercise capacity, Invalidates most procedures that require an age-predicted maximal heart rate to estimate exercise intensity.
QUINAPRIL (Class: A.C.E Inhibitors) Function: ACE inhibitors is short for Angiotensin Converting Enzyme inhibitors. Their function is to promote vasodilation by preventing angiotensin I being converted to angiotensin II which causes vasoconstriction and circulatory volume retention. These will improve left ventricular function. Side Effects: Hypotension, Dry cough, Renal impairment, Nausea, Fever, Rash, Headache, Fatigue, Dizziness. Other common A.C.E Inhibitors: Enalapril, Ramipril. Exercise relevance: Postural hypotension (avoid fast postural changes and sudden standstill), Dizziness, Irritating cough, Fatigue.
NIFEDIPINE (Class: Calcium Channel Blockers) Function: to reduce the flow of calcium to the vascular smooth muscle (blood vessels) causing a weaker contraction and relaxation of the vessel. Side effects: Ankle swelling, Ankle and foot pain, Flushing to the face, Bradycardia (Only some drugs - Diltiazem being one), Headaches, Constipation, Urinary frequency in men, Muscle cramps. Other common Calcium Channel Blockers: Diltiazem, Amlodipine Exercise relevance: Postural hypotension (avoid fast postural changes and sudden standstill), Dizziness, Syncope, Muscle cramps, Fatigue.
PRAZOSIN (Class: Alpha-Adrenoceptor Blockers) Function: to facilitate vasodilation by blocking the effect of noradrenaline in peripheral arteries and smooth muscles. This will see a reduction in resistance to blood flow. Side effects: Postural hypotension, Drowsiness, Dizziness, Headache, Vertigo, Nausea, Fatigue, Depression. Other common Alpha Blockers: Doxazosin, Indoramin. Exercise relevance: Postural hypotension (avoid fast postural changes and sudden standstill), Syncope, Dizziness