Exercising for between 150 and 300 minutes per week, with a couple of muscle-strengthening sessions, is enough to guarantee health benefits.
Physical activity is one of the essential factors for a healthy life. Along with not smoking, consuming alcohol moderately and healthy eating habits, exercise is considered one of the most effective ways to prevent the onset of numerous diseases in the course of a lifetime: heart disease, stroke, diabetes, lung or bone disease, as well as several forms of cancer.
But what exactly is meant by physical activity? We often tend to associate it with sports, or planned, structured exercise, such as running or going to the gym. In actual fact, physical activity has a much broader definition: according to the World Health Organisation, it is “any bodily movement produced by skeletal muscles that requires energy expenditure”. This means that the term physical activity includes all the daily pursuits that involve movement: going from one place to another, leisure activities, sport, common household chores, gardening, as well as any work activities that entail physical movement.
Of course, not all forms of exercise are the same in terms of their effects on the body. Some require minimal energy expenditure while others push our physical capabilities to the limit; some have a more significant impact on the cardiovascular system while others train our muscles or sense of balance.
For many years, the scientific community has been conducting research in an attempt to understand what type and how much exercise each category of person requires in order to achieve sustained health benefits. So far, studies have made it clear that there are two overriding principles which are valid for everyone, regardless of age: any type of physical activity is better than no physical activity at all, and the benefits are greater the longer the habit of being active can be maintained.
This doesn’t mean that people who have been lazy in the past won’t benefit from starting to exercise, albeit belatedly. Mindful of these principles, scientific experts have developed specific guidelines according to people’s age and specific characteristics (such as pregnancy, or physical conditions that limit the ability to exercise). The latest World Health Organisation guidelines on this subject date back to 2020 and they were applied in Italy in November 2021 by means of recommendations issued by the Ministry of Health.
The WHO guidelines are not designed specifically to reduce the risk of getting cancer, their aim is to protect health in general terms. However, by following these guidelines, it is possible to reduce the likelihood of developing various types of cancer.
The distinction most often found in exercise guidelines is between moderate and vigorous physical activity. Moderate refers to physical activity that causes a modest increase in heart and breathing rates, generally leaving it possible to have a conversation relatively easily (but not to sing) while doing it. For example, brisk walking. This type of physical activity uses 3 to 6 times the energy that is generally consumed at rest.
Vigorous physical activity, on the other hand, increases the heart and breathing rates to levels at which it is difficult to talk. Jogging is a good example. This type of physical activity uses at least six times more energy than at rest.
What is the recommended level of physical activity? Here is some general guidance according to the different age groups.
ADULTS
In the 18-64 age group, the recommendation is to ensure at least 150 to 300 minutes of moderate aerobic exercise per week, or at least 75 to 150 minutes of vigorous physical activity. To give an example, these goals can be achieved with five moderate-intensity exercise sessions lasting at least 30 - 60 minutes per week, or at least 25 - 50 minutes of vigorous exercise three times a week.
Muscle-strengthening activities (exercises such as press-ups, squats, weight training, etc.) should also be included in the exercise schedule at least twice a week, not on consecutive days. Adults are also advised to limit the amount of time they spend sitting down, and to spend at least part of the time they would otherwise be inactive doing physical activity of any intensity, when possible.
OVER-65s
Being older doesn’t mean that physical activity is no longer advisable. Quite the contrary, it would be best to try to increase it if possible, diversifying the kind of activities. According to the WHO guidelines, people over the age of 65 should continue moderate-intensity aerobic exercise for at least 150-300 minutes per week, or vigorous aerobic exercise for 75-150 minutes. Muscle-strengthening exercises should be added to this routine twice a week or more. In order to maintain physical capabilities and prevent falls at this age, it is a good idea to do multicomponent activities at least three days a week, i.e., a combination of aerobic activity, muscle strengthening and balance training.
The most common chronic conditions, such as hypertension or diabetes, are not a contraindication to physical activity after the age of 65. The suggested levels of exercise are similar to those of healthy individuals in the same age group, taking any personal limits into due consideration. Again, the principle is that it’s much better to do just a little exercise than to give it up completely for fear of not achieving the recommended levels.
Any doubts about whether engaging in physical activity is compatible with an ongoing medical condition should be discussed with a doctor or other healthcare professional who will provide guidance.
CHILDREN AND TEENAGERS (5-17 YEARS OLD)
Children and teenagers should do at least 60 minutes per day of moderate or vigorous physical activity, mostly aerobic, throughout the week. Three days a week should include vigorous aerobic exercise as well as muscle and bone strengthening activities. It is also very important to limit the amount of time they spend sitting down, especially in front of a screen - TV, computer or smartphone.
At first glance, the physical activity levels recommended by the guidelines are quite ambitious: at least 30 - 60 minutes of basic exercise per day for adults and 60 for children, to which at least 2/3 more strenuous training sessions should be added each week. The problem isn’t just the tendency to prefer being idle; daily life is increasingly complicated to organise, work and responsibilities can take over, while children have a lot of schoolwork and extracurricular activities which seem to leave little room for exercise. However, health experts and organisations have been advising us for years to change our approach and start considering exercise as a key part of everyday life, rather than just an extra task to try to fit into our lives.
This new approach opens our eyes to countless opportunities to stay active every day: walking or cycling to work or school; getting off public transport one stop early and finishing the journey on foot; not taking the car for short trips; walking up the stairs instead of using the lift; walking the dog; getting involved in gardening or housework; playing with any children in the family. Choosing to include these ordinary activities in our daily routine helps achieve, or come very close to, the recommended goals for physical exercise.
There is, however, another aspect to be taken into consideration. Physical activity alone is not enough if the tendency to be sedentary is not also addressed. This sounds like nonsense, but in actual fact being sedentary and being physically inactive are not the same thing. It is possible to be physically active, achieving the recommended amount of exercise, but still have a sedentary lifestyle. Imagine someone who goes for a jog in the morning, but then spends the rest of the day in a car or sitting at a desk. Spending all that time sitting down is considered an additional risk factor to simple being inactive in terms of exercise. There are no conclusive data on this, but several studies seem to show that the recommended levels of physical activity can counteract or at least mitigate the negative effects of a sedentary lifestyle.
This is one of the reasons behind the advice from the scientific community, which recommends frequently interrupting periods of sitting with short, active breaks, at least every 30 minutes, even just for 2-3 minutes. Take a short walk, bend or stretch, or simply get up repeatedly from a chair or sofa. Alternating sitting and standing regularly is another simple measure that can help counteract the damage caused by being sedentary.