Dr. C.V. Alert, MB BS, DM. FCCFP. Family Physician.
When it comes to exercising for health, you don’t want to peak too early in life. Life is not a sprint; it is a marathon. Pre-teens, teenagers, and those in their early 20s may be physically active, but as we get older, the level of physical activity drops. It is not coincidental that as we age and become less active, a number of medical illnesses that are ‘exercise-sensitive’ become prominent. These include obesity, diabetes, hypertension, heart disease, strokes—non-communicable diseases (NCDs)—and many cancers. Among older individuals who may have already developed one or more of these diseases, exercise is a crucial part of treatment, rehabilitation, and preventing further health deterioration. In this group, exercise helps many maintain their independence and leads to an improved quality of life.
Exercise also has a significant impact on mental health, which will be covered in another article.
Many international bodies, like the American College of Sports Medicine (ACSM) and the American Heart Association (AHA), have promoted their recommendations for health maintenance in adults for many years: do at least 150 minutes of moderate-intensity activity a week or 75 minutes of vigorous-intensity activity a week. Further exercise recommendations include spreading the activity evenly over at least 4 days each week, though 7 days is even better; doing strengthening activities that work all major muscle groups (legs, hips, back, abdomen, chest, shoulders, and arms) on at least 2 days a week; reducing time spent sitting or lying down; and breaking up long periods of inactivity with some activity. You can also achieve your weekly activity target with several short sessions of very vigorous intensity activity or a mix of moderate, vigorous, and very vigorous intensity activity. [There are separate recommendations for muscle strengthening activities, not covered here.]
These guidelines are also suitable for disabled adults, pregnant women, and new mothers. When you start exercising after pregnancy, make sure your physical activity choices reflect your activity levels before pregnancy. Vigorous activity is not recommended if you were inactive before pregnancy.
Moderate Aerobic Activity Moderate activity will raise your heart rate, make you breathe faster, and feel warmer. One way to tell if you’re working at a moderate intensity level is if you can still talk, but not sing. Examples of moderate-intensity activities include brisk walking, water aerobics, cycling, dancing, doubles tennis, pushing a lawn mower, or even hiking (up to the ‘grin and bear’ level).
Vigorous Activity Vigorous intensity activity makes you breathe hard and fast. If you’re exercising at this level, you will not be able to say more than a few words without pausing for breath. In general, 75 minutes of vigorous intensity activity a week can give similar health benefits to 150 minutes of moderate intensity activity. Examples of vigorous activities include running (sprinting), swimming, riding a bike fast or up hills; sports like football, rugby, netball, and hockey; skipping, aerobics, gymnastics, and martial arts.
Very Vigorous Activity Very vigorous activities are exercises performed in short bursts of maximum effort broken up with rest (‘catch your breath’ periods). This type of exercise is also known as High-Intensity Interval Training (HIIT). Examples of very vigorous activities include lifting heavy weights, circuit training, sprinting up hills, interval sprinting, and running up hills or stairs.
Children and young people also need to do physical activity every day. For children and young people aged 5 to 18, the recommendations are: aim for an average of at least 60 minutes of moderate or vigorous intensity physical activity a day across the week; take part in a variety of types and intensities of physical activity across the week to develop movement skills, muscles, and bones; reduce the time spent sitting or lying down and break up long periods of inactivity with some activity. Aim to spread activity throughout the day.
However, we know that exercise levels fall off as we get older. Opportunities for physical activity present in high school diminish as individuals’ transition through university, join the workforce, and navigate early parenthood; exercise time becomes ‘just a rumor’. It is important to get in as much exercise as possible when you are young to head off these ‘exercise-sensitive’ diseases in mid-life and old age. Thus, young adulthood is an important opportunity to intervene and head off these diseases that often show up in middle age and beyond. Therefore, it is crucial to focus on pre-adults, ensuring they get sufficient exercise for long-term health maintenance. There is some evidence from limited research that increasing or even doubling the amount of exercise currently recommended for adults aged 18-65 years in young people may lower the risk for hypertension and other ‘exercise-sensitive’ diseases later in life. Hence, the guidelines for promoting exercise in pre-adults and young adults for disease prevention (as opposed to health maintenance) should recommend increasing (perhaps doubling) the current levels of exercise recommended for adults. This is similar to the exercise recommendations for promoting weight loss in obese patients; such individuals need to double up on their age-specific exercise recommendations if weight loss is the goal.
Children and young people aged 5 to 18 who are living with a disability should aim to do a minimum of 20 minutes of physical activity a day, splitting this into smaller chunks of activity throughout the day if needed. They should also do challenging but manageable strength and balance activities 3 times a week.
What Counts as Moderate Activity for Children and Young People? Moderate intensity activities have a similar definition in children as in adults: you breathe faster, you can talk, but you can’t sing. Examples include walking to school or walking the dog; playground activities like jumping, running, and catching; physical education; sports like football or tennis; swimming; skipping; dancing; skateboarding, and cycling.
For older adults (generally 65 years and older), the focus of exercise is slightly different. Older adults should do some type of physical activity every day to improve health and reduce the risk of heart disease and stroke. Adults aged 65 and over should aim to be physically active every day, even if it’s just light activity. They should do activities that improve strength, balance, and flexibility on at least 2 days a week, and aim for at least 150 minutes of moderate intensity activity a week or 75 minutes of vigorous intensity activity if they are already active, or a combination of both. Reducing time spent sitting or lying down and breaking up long periods of inactivity with some activity is crucial. If there is a fear of falling, or a history of falls, doing exercises to improve strength, balance, and flexibility will help individuals become stronger and more confident on their feet.
To maximize the benefits of exercise throughout life, we should encourage our young people to exercise as much as possible, starting early and continuing into old age. There may be a ‘legacy effect’: the longer you keep exercising when you are young, the longer the health benefits may persist into late adulthood and even old age. When planning to exercise, don’t prepare for a sprint, but prepare for a marathon.
Here are the key points:
Exercise: From the Womb to the Tomb
- Exercise Throughout Life:
- It’s crucial to maintain physical activity throughout life to prevent exercise-sensitive diseases such as obesity, diabetes, hypertension, heart disease, strokes, and many cancers.
- Older adults with such diseases benefit significantly from exercise for treatment, rehabilitation, and prevention of further health deterioration.
- International Exercise Recommendations:
- The American College of Sports Medicine (ACSM) and the American Heart Association (AHA) recommend at least 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity activity per week for adults.
- Activities should be spread over at least 4 days a week and include muscle-strengthening exercises on at least 2 days a week.
- Recommendations also apply to disabled adults, pregnant women, and new mothers.
- Types of Activities:
- Moderate Aerobic Activity: Includes activities like brisk walking, cycling, and dancing, where you can talk but not sing.
- Vigorous Activity: Involves activities like running, swimming, and sports, where talking is difficult without pausing for breath.
- Very Vigorous Activity: Consists of High-Intensity Interval Training (HIIT) like sprinting and lifting heavy weights.
- Children and Young People:
- Children aged 5 to 18 should aim for at least 60 minutes of moderate or vigorous intensity physical activity daily.
- Disabled children should aim for a minimum of 20 minutes of activity daily, with strength and balance activities three times a week.
- Importance of Young Adulthood:
- Young adulthood is critical for establishing exercise habits to prevent exercise-sensitive diseases later in life.
- Evidence suggests increasing or doubling exercise levels for young adults to lower the risk of such diseases.
- Older Adults:
- Adults aged 65 and over should do physical activity every day, focusing on strength, balance, and flexibility exercises.
- They should aim for at least 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity activity per week.
- Legacy Effect:
- The benefits of exercising when young may persist into late adulthood and old age, emphasizing the importance of lifelong physical activity.