South Africa has the third highest incidence of heart disease in the world – in fact, every 10 minutes, a South African has a heart attack and a fatal heart attack occurs every 45 minutes.
Andrew Heilbrunn, from the Centre for Diabetes and Endocrinology’s Biokinetic Centre in Johannesburg, says inactivity and low physical fitness contribute substantially to increasing rates of heart disease and stroke. This is particularly significant considering the diabetes and obesity epidemics sweeping through our country. In South Africa, 4 out 10 men and 7 out of 10 women are overweight or obese – this is a major risk factor for the development of type 2 diabetes, a largely asymptomatic condition with potentially devastating cardiovascular outcomes if undiagnosed or untreated. Figures released earlier this year by StatsSA report that diabetes became the biggest killer of South African women in 2015, and the second biggest killer overall, up from fifth two years ago.
Heilbrunn says there have been some landmark studies over the last couple of decades, two of the most notable being the Cooper Centre longitudinal study by Dr Steven Blair and another study by Dr Ming Wei. Blair analysed the fitness of 25 341 men and 7 080 women over a 20-year period. Of interest, the inactive and unfit participants appeared to have a higher risk for heart disease and strokes, than those with high blood pressure, high cholesterol, diabetes and those who were overweight.
Blair and Wei also showed that men who were obese, but moderately fit had a significantly lower risk of heart disease than men who were obese, but unfit. In fact, men who were obese but fit had a far lower death rate than men of normal weight who were unfit.
“In other words,” says Heilbrunn, “as long as you are relatively fit or relatively active for 45 to 60 minutes per day, even if you are overweight, you will have significant protection against heart disease and stroke. This is particularly important for people with type 2 diabetes who struggle with their weight.”
Traditionally the preferred approach to weight loss has been calorie restriction and exercise has been seen as a means to maintaining weight loss. “Both exercise and calorie restriction have their pros and cons – however, a combination is definitely best,” he says. The question then becomes “how much exercise is necessary to bring about weight loss and physiological adaptations to decrease mortality?”
Study results vary from 75 minutes per day, to 30 to 60 minutes 7 days a week to 60 minutes every day. The CDE Fitness Centre proposes a practical combination of endurance and resistance training 3 to 4 times per week for 30 to 60 minutes coupled with informal activity such as gardening, shopping, housework, DIY work etc.
“There is no doubt that exercise can play a key role in the prevention and management of obesity and diabetes. It improves overall fitness, promotes blood glucose control, reduces body fat and cardiovascular risk and improves the overall quality of life. If prescribed appropriately and overseen by a professional, exercise can be an extremely safe and effective treatment and prevention strategy,” concludes Heilbrunn.