We all need to include exercise or physical activity in our lives in a way that is healthy and can be maintained. To do so, we must understand what physical activity is, what it can do for us, and what we should expect from it.
Many people use the words ‘exercise’ and ‘physical activity’ in the same way. However, physical activity refers to any body movement that burns calories. This includes movement for exercise, work, chores and play.
Two major subgroups of physical activity exist: exercise and NEAT (Non-Exercise Activity Thermogenesis). Exercise means planned, structured and repetitive activities aimed at improving fitness and health. NEAT refers to regular movement in everyday life. Movement at work, doing chores at home, and fidgeting are all examples.
Most health experts use the term physical activity because it includes both types of movement. Over the last few decades, physical activity levels (mostly NEAT) worldwide have dropped. This change contributes, in part, to rising rates of obesity around the world.
Ample evidence shows that higher levels of physical activity can reduce the risk of many chronic health conditions. It lowers the risk of heart disease, stroke, high blood pressure, type 2 diabetes, osteoporosis, and weight gain, as well as various cancers. Higher levels of physical activity also allow people to do daily tasks with more ease and comfort, and with less fatigue.
There is no question that the more physical activity we get, the greater the benefits to our health. The Canadian Physical Activity and Sedentary Behaviour Guidelines Handbook, published in 2012, provides guidelines (see sidebar). It describes the amount and types of physical activity that offer health benefits to Canadians of all ages. We can reduce health risks by limiting the amount of time that we are sedentary. Being sedentary means doing activities that involve very little movement, such as watching TV, playing video games and sitting.
Adults 18 years of age and older are advised to accumulate at least 150 minutes of moderate to vigorous intensity aerobic physical activity each week. Aim for bouts of 10 minutes of activity or more. Adults are also encouraged to add activities that strengthen muscles using major muscle groups, at least twice a week. This amount of physical activity can reduce the risk of heart disease, stroke, high blood pressure, type 2 diabetes, certain cancers, osteoporosis, and premature death. It can also improve fitness, strength and mental health. According to Stats Canada, only one in five Canadian adults were meeting these guidelines in 2012 and 2013.
Generally speaking, obesity comes from an imbalance of energy. This means the calories consumed (eaten) are higher than the calories burned. Many factors influence this equation, including some we are not able to control. However, we can control other factors, including the amount of physical activity we get. Activity influences the number of calories burned. In combination with healthy changes in the diet, increased physical activity may help to reduce and maintain a lower weight. Although many studies have shown that physical activity alone does not result in very significant weight loss, it may help to prevent weight gain.
Researchers believe that physical activity helps manage weight in a few different ways.
Being moderately active for 150 minutes per week lowers the risk of many diseases. To maintain a healthy weight or lose weight, most people need around 300 minutes of activity per week.
Guidelines published by the American College of Sports Medicine (ACSM) give more precise idea of what is needed.
ACSM also recommends strength training as part of this health and fitness routine.
Any and all movement is beneficial. However, to really reap the rewards of physical activity, we must increase the total amount of movement and also be active at the right intensity. We must not push too hard or do too little. For the greatest health benefit, aim for an exercise intensity that is moderate to vigorous. To manage weight, a moderate intensity activity is best.
The intensity of activity appears in our breathing, heart rate, whether we sweat and how tired we feel. Some people like to assess intensity by measuring their heart rate. The easiest way to check is to consider how you feel.
Many people feel pressure to increase the amount of time they spend doing structured exercise. However, remember that all physical activity is important. We live in an environment where it is very easy to move less – at home, at school, at work – everywhere. Instead of trying to find more time to exercise, consider how you can increase activity in all areas of your life. Here are a few suggestions.
Physical activity has many benefits. Moderate Intensity aerobic physical activity (150 minutes each week) can reduce the risk of many chronic diseases. However, to maintain a healthy weight, more is needed. At least 300 minutes per week seems necessary to counteract the effects of increasingly sedentary lifestyles and to prevent weight gain. Remember to deliberately increase physical activity and movement in all areas of your life, rather than just ‘exercising.’ Of course, the most important thing is to have fun while being active!