Exercise can prevent high blood pressure
As far back as the 1960s, the Honolulu Heart Study showed that active men were less likely to develop high blood pressure, diabetes, obesity, raised cholesterol levels or experience a heart attack or stroke than men who led a sedentary life. Twenty years later, the Harvard alumni study showed that men who took part in vigorous sports were 35% less likely to develop high blood pressure over a 10 year period than those who were physically inactive. A year later, both men and women in the Aerobics Center Longitudinal Study were found to have a 52% higher risk of developing hypertension than those who were physically active.
Researchers now know that regular exercise has many beneficial effects on blood pressure regulation, cholesterol balance, blood clotting and glucose control. So much so, that taking regular exercise reduces your risk of premature death from coronary heart disease by more than 40%, and your risk of age-related death from all causes by around a quarter – even if not started until middle age. Even in those with pre-existing heart problems, regular exercise appears to reduce the risk of early demise by 25%, at any age, compared with those who take no exercise at all.
How exercise reduces blood pressure
Exercise dilates blood vessels and reduces the force against which your heart has to pump blood through the circulation. It boosts blood flow through your muscles so that pressure elsewhere in the body is reduced. Exercise also ‘burns off’ the effect of stress hormones and promotes relaxation by stimulating the release of opium-like endorphins in the brain.
As well as reducing blood pressure at rest, increased fitness reduces the rise in blood pressure that occurs during intense physical activity and emotional distress.
A study involving sedentary, obese, hypertensive males, published in the American Journal of Hypertension, showed that a single session of aerobic exercise, lasting 45 minutes, of moderate intensity, significantly reduced average systolic blood pressure by between 6 mmHg and 13 mmHg for the first 16 hours after exercise, compared to a day in which the men did not exercise. Overall, their average systolic and diastolic blood pressures remained significantly lower for 24 hours after exercise.
Exercise physiologists have now confirmed that it’s wise to exercise regularly, every day, so the benefits of a single bout of exercise persist. As soon as you stop exercising, the beneficial effects on blood pressure, cholesterol levels and glucose tolerance are rapidly lost.
How much exercise do you need?
Physical activity doesn’t need to be vigorous. Brisk walking for 30 to 60 minutes a day, most days of the week, produces significant benefits for people with hypertension.
Activities such as gardening and dancing are just as effective as swimming or cycling for heart health. Any activity that leaves you feeling warm and slightly out of breath is doing you good.
Researchers have also found that exercise doesn’t have to be completed all in one go – you can divide it into two or three daily sessions of 10 – 15 minutes if you prefer.
The exercise needs to be brisk enough to raise your pulse above 100 beats per minute, raise a light sweat and make you slightly breathless – but not so much that you cannot hold a conversation.
Reassuringly, heart specialists in Australia, who studied the effects of exercise in 500 males, found that, during treadmill tests carried out after one year, those who took light exercise using a bicycle, step and rowing machine, with plenty of rests, were just as fit as those who continuously jogged or walked for 30 minutes.
Use Your Pulse Rate
Measuring your pulse rate during exercise will ensure you stay within the safe range for burning excess fat and improving cardiovascular fitness, without over-stressing your heart.
Your pulse is most easily felt:
- On the inner side of your wrist on the same side as your thumb (radial pulse)
- At the side of the neck, under the jaw (carotid pulse).
Take your ten-second pulse every ten minutes or so during your exercise period.
To do this, stop briefly and place your finger on the carotid pulse at the side of your neck which is easiest to find. Look at your watch, and count the number of pulses you feel during a 10 second period.
The optimum 10 second pulse range for your age is shown on the following chart:
AGE 10 Second Pulse Range
20 – 29 20 – 27
30 – 39 19 – 25
40 – 49 18 – 23
50 – 59 17 – 22
60 – 69 16 – 21
70 + 15 – 20
If you are unfit, make sure your pulse stays at the lower end of your 10 second pulse
range at first, and slowly work up towards the upper end of the 10 second pulse range for your age over several weeks.
If at any time your pulse rate goes higher than it should, stop exercising and walk around slowly until your pulse falls. When you restart, take things a little more easy. At the end of 20 minutes exercise, you should feel invigorated rather than exhausted.
Try taking your pulse one minute after stopping exercise, too. The more rapidly your pulse rate falls, the fitter you are. After 10 minutes rest, your heart rate should fall to below 100 beats per minute. If you are very fit, your pulse will drop by up to 70 beats in one minute.
Remember to warm up before any form of exercise with a few simple bends and stretches. Similarly, it is important to cool down afterwards with stretch exercises or by walking slowly for a few minutes. These measures help to avoid muscle injuries, pain and stiffness. For comfort, wear loose clothing and footwear specifically designed for the exercise you have chosen, and use any recommended safety equipment. Don’t exercise straight after a heavy meal, after drinking alcohol or if you feel unwell. As always, stop immediately if you feel dizzy, faint or unusually short of breath and, if you develop chest pain, seek immediate medical advice.
NB: If you are taking medication, seek medical advice before starting a physical exercise programme.
If your blood pressure is raised, self-monitoring is key to maintaining good control.
Click here for advice on choosing a blood pressure monitor to use at home.
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