Exercise is medicine
Epidemiological studies have shown that physically active individuals are healthier and live longer
than sedentary ones. Scheduling in even small amounts of exercise into your daily routine can have
major impacts on your health.
How much do I need every week?
According to the 2018 Physical Activity Guidelines Advisory Committee Scientific Report to
achieve substantial health benefits, most people should undertake a combination of aerobic
and resistance exercises, including:
- At least 150–300 minutes a week of moderate-intensity, or 75–150 minutes a week of vigorous-intensity aerobic physical exercise, or an equivalent combination of moderate and vigorous-intensity aerobic training
- Muscle-strengthening activities of moderate or greater intensity that involve all major muscle groups on two or more days a week.
Balance and flexibility exercises are important as well. The new guidelines also recommend that preschool children (aged 3 to 5 years old) should be physically active throughout the entire day; children and adolescents should perform at least 60 min of moderate-intensity to vigorous-intensity physical activity daily; and even pregnant and postpartum women should accrue 150 minutes weekly of moderately intense aerobic activity.
How harmful is too much sitting?
Physical activity is no longer a requirement for daily living for most people in Australia and
many other industrialised countries. The relationship between eating and manual labour has
been quashed. Today mechanised, technology-driven conditions allow and even promote
an unprecedentedly sedentary lifestyle. A growing number of men and women spend
between 65 to 80 percent of their day just sitting. New research suggests that prolonged
periods of inactivity – for instance, the number of hours per day spent to watch television or
to work at a computer – are associated with an increased risk of developing and dying from
cardiovascular disease, cancer (especially, breast, endometrium, ovary and colorectal) and
diabetes regardless of the degree of obesity and the number of exercise sessions held during
the week.
Does exercise help you lose weight?
It is commonly thought that exercise does next to nothing when it comes to losing weight.
Several studies have shown that endurance exercise three times per week at moderate
intensity results in no or modest weight loss beyond what is achieved with dietary change.
However, results from our 1-year randomised clinical trial, conducted at the Washington
University of St.Louis, in overweight men and postmenopausal women aged between 50 and
60, showed that marked reductions in body weight can be achieved. A 40 percent loss in
abdominal fat was attributed to an endurance exercise program consisting of six hour-long
sessions per week, at an intensity of 72 percent of maximum heart rate.
How to slow aging with exercise?
Animal studies have shown that regular endurance exercise training improve metabolic
health (average lifespan), but does not slow aging (it does not increase maximal lifespan). In
contrast, animals that had the same body weight as the exercising rats because of dietary
restriction (they were eating 30 per cent less food) experienced a big increase in both
average and maximal lifespan.
Why is it important to exercise regularly?
Data from multiple clinical studies have shown that when people stop exercising, they lose
the positive benefits of metabolic, physiologic and performance capacity very quickly. This
phenomenon is called detraining. Seven to 14 days of detraining is sufficient to significantly
decrease both metabolic and fitness health benefits.
The many ways exercise protects your heart
Besides the positive effects of walking, running or swimming on blood glucose and insulin
levels, they also have beneficial effects on HDL-cholesterol and blood fat levels. Regular
endurance training also decreases blood pressure, especially in patients with hypertension.
Aerobic exercise also contributes to a reduction in body weight and inflammatory markers
and has beneficial effects on cardiovascular health, including improved arterial function.
Unsurprisingly, the odds of having a heart attack or a stroke is lower in people who do
regular aerobic physical exercise.
