In the struggle for weight control and general good health, much importance is given to the type and amount of food and drink being consumed. Less attention has been given to the amount of energy spent if we were physically active. But both aspects are closely linked. Unlike our ancestors, we no longer need to use too much energy to find food. Due to technological advances, the motor transport, automation and labor-saving machinery, most people have fewer opportunities to expend energy. It has been shown that approximately 70% of the population in Western countries is not sufficiently active to be able to enjoy good health and maintain weight.
1. What does physical activity means?
Physical activity, exercise, fitness - all these terms are commonly used to refer to the physically active. Yet in terms of science, may have slightly different meanings. The most commonly used terms are defined in the following table.
Definitions related to physical activity:
- Physical Activity: is the total energy consumed by the movement of the body. It includes daily routine activities such as housework, shopping, work.
- Exercise: Changes planned and designed to be fit and enjoy good health.
- Sports: Physical activity performed as competition, is governed by rules. In many European countries, the term covers all types of sports exercises and physical activities during leisure time.
- Fitness: series of attributes such as strength, mobility and strength, which require performing physical activities.
Physical activity refers to all the energy spent to move. The best physical activities are the daily activities, which may move the body, such as walking, biking, climbing stairs, doing household chores, shopping, and most of them are an inherent part of our routine. On the contrary, the exercise is a planned and intentional effort, at least in part, to improve fitness and health. May include activities like riding, cycling, aerobics and maybe on some active hobbies such as gardening and competitive sports.
The physical form is mainly the result obtained, according to our levels of physical activity, but genetic factors are important, thanks to which some people have a natural ability and a fit to highlight some activities. This is more noticeable in competitive sports such as racing background or weightlifting, where the best participants are those with a genetically superior body, i.e. it is in optimal conditions, without excessive training. Still, it's important to remember that the evidence available to date show that what may help us enjoy good health (more than any inherited component of good form) is to perform regular physical activity. This means that everyone, we are naturally athletic or not, we can benefit if we increase our physical activity.
2. What are the benefits of physical activity?
Increased physical activity has many compensations, including reduced risk of certain diseases and conditions, and improving mental health.
2.1. Heart disease and strokes
Heart diseases are the leading cause of death in Europe. Lead an active lifestyle, with a moderately high level of aerobic exercise, can reduce the chances of contracting serious heart disease or die for their cause. The benefits that exercise brings to the health can be noted if moderate physical activities, and are more evident in the sedentary people who change their habits and become more active. Activities such as walking, biking regularly or four hours per week of physical activity reduces the risk of suffering heart ailments. It was also found that physical activity helps to recover from heart disease, through rehabilitation programs that are based on the year and are effective in reducing the risk of death. The effects of physical activity on stroke are less clear, since the findings of various studies are contradictory.
2.2. Obesity and excess weight
To keep the weight, there must be a balance between energy spent and energy consumed. Obesity develops when consuming more than spent during a certain period of time. It is thought that obesity is a direct consequence of the changes that have occurred in our environment, including the availability of labor-saving tools, motorized transport, sedentary entertainment such as watching television and easier access to high calorie foods at a lower price. The incidence of obesity has tripled in the last 20 years and now in Europe between 10-20% of men and 10-25% of women are obese (data from IOTF) (Index Body Mass Index> 30). Evidence is increasingly obvious saying that reducing the levels of physical activity is a key factor in increasing obesity. In fact, it appears that the amount of physical activity that takes place can be an even more decisive factor in the development of obesity that the energy intake (calories).
There are several studies showing that obesity is preventable leading an active lifestyle and keeping fit. In particular, it appears that the activity prevents weight gain is often given to people in middle age.
Exercise can help people who are already obese or overweight, lose weight, if combined with a hypocaloric diet (low calorie) and can improve body composition because it keeps the muscles and increases fat loss. Physical activity is also effective in reducing abdominal fat (where the fat accumulates in the stomach and chest), which is associated with an increased risk of diabetes or heart disease. Moreover, people who exercise regularly are more likely to maintain weight loss long term.
Perhaps the biggest advantage is that physical activity by obese people is their effect on risk profile. It has shown that obese people who manage to remain active reduce the risk of suffering from heart disease and diabetes, to levels similar to those of non-obese. This would demonstrate that it is unhealthy to be obese if you are not fit.
2.3. Diabetes in adults
The incidence of type 2 diabetes has increased rapidly. Often attributed to an increase in obesity, although there is evidence that inaction is also a risk factor.
According to studies, people who are most active has less risk of developing diabetes by 30-50 % lower than in those who are sedentary. It has been shown that exercise may delay or prevent the glucose intolerance becoming diabetes and is also beneficial for persons who have been diagnosed with diabetes. There are some interesting studies have shown that exercise such as walking or biking three times a week for 30-40 minutes, can make small but significant improvements in glycemic control (blood sugar) in diabetics.
It seems that being physically active reduces the risk of developing certain cancers, and that moderate to intense activity is the best way to protect yourself. For example, exercise reduces the risk of developing cancer of the colon or rectal cancer in 40-50%. Physical activity might also have an impact on other types of cancer, but still not enough evidence to prove it.
2.5. Improvement of bones and muscles
Exercising on a regular basis can be beneficial to disorders and diseases affecting the muscles and bones (such as osteoarthritis, back pain and osteoporosis). Make helps strengthen muscles, tendons and ligaments and bones densify. Physical activity programs are designed to improve muscular strength, which have proved useful in helping older adults maintain balance, which may be useful to reduce falls.
The exercise is also effective in preventing back pain and reduces the recurrence of back problems. However, it is unclear what type of exercise is best for back pain. There is no evidence that physical activity helps prevent osteoarthritis, but have found that walking reduces pain, stiffness and disability and improve strength, mobility and quality of life.
Sports (which include exercises in which they bear the weight of the body, in addition to moderate and intense activities) may increase the mineral density and bone size in adolescents, help maintain it in adults and their slow decline in the elderly. This can help prevent or delay the onset of osteoporosis, but cannot reverse the process once the disease has developed.
2.6. Improving mental conditions
Numerous studies have shown that physical activity reduces the clinical depression and can be as effective as traditional treatments, such as psychotherapy. If exercise is done regularly for several years also reduces the risk of depression recurrence.
It was also found that physical activity improves psychological health in people who do not suffer from mental disorders. Hundreds of studies have documented improvements in subjective health, mood and emotion, as well as the self-perception of body image and physical self-esteem.
Moreover, both the short periods of activity such as sports training in reducing anxiety and improving responses to stress, as well as the quality and length of sleep. It has been shown that exercise enhances some aspects of mental functioning such as planning, short-term memory and decision making.
It seems that physical activity is especially good for older people, and reduces the risk of dementia and Alzheimer's.
3. What is the downtime cost?
The human body is designed to move, and so a sedentary life can result in diseases and even premature death. In a review of 44 studies found that adults who have a moderate physical activity, especially during middle age and beyond, are twice as likely as sedentary people to avoid an early death and the development of serious diseases. The level of profits for health is similar to quitting smoking is achieved, and today it is recognized that inactivity is a risk factor in heart disease.
How this translates into economic costs? Disease and premature death make the victims suffer, and the friends and family, but also pose an enormous financial cost with regard to absenteeism by low and health care. Most studies have been conducted in the United States, and they estimated that 18% of cases of heart disease (at a cost of 24,000 million U.S. dollars - 1995) and 22% of cases of colon cancer (cost of 2,000 million U.S. dollars) in the population, may be caused by inactivity. Today, we know that medical expenses for active people are 30% lower than those of inactive people.
It is estimated that in Britain, which has the highest percentage of obesity in Europe (about 20% of the population, which is at least partly due to inactivity), costs of Obesity is 500 millions.
4. What risks are associated with physical activity?
There is no action that does not involve risk, and exercise is no exception. For example, the possibility of suffering a sudden cardiac death during intense physical exercise is multiplied by 5 in people with good shape and 56 people in low form. It also increases the risk of injury, particularly in the feet, ankles and knees, when performing intense exercise or sports. Finally, much of the media attention has focused on the addiction to sport, to the people who are 'hooked' and overlook other aspects of life such as work or social relationships. Although we have identified a syndrome of dependency on the sport, it is very rare, and usually is associated with other psychological problems such as anorexia nervosa, the excessive neurotic and obsessive-compulsive disorder.
5. How much physical activity we need?
For many years, educators have adopted methods of physical training to improve cardiovascular health, which consisted of vigorous exercise in which worked with large muscle groups for at least 20 minutes followed, with high intensity (equivalent a 60-80% maximum heart rate). Unfortunately, it was noted that this level of exercise was too intense for most people, who remained inactive.
The most recent recommendations in the U.S. and the UK have performed physical activity of moderate intensity. It is thought to be much easier for a greater percentage of the population carrying out moderate physical activities like walking as this kind of exercises can be incorporated more easily into daily routines and require less physical effort. Walking for 20 minutes a day can make a difference of 5kgs per year and contribute to better cardiovascular health, as well as providing other benefits physically and mentally. Currently, the recommendations emphasizet walking for thirty minutes every or nearly every day of the week. There is evidence that the same amount of exercise in two or three short space of time can be almost as effective and easier to cope if done daily.
Different types and intensities of physical activity will help to improve different aspects of health and fitness. For example, although a slight walk to the lunch hour is not intense enough to improve cardiovascular health, can help make a healthy break at work, improve mood and reduce stress, and contributes also to control weight. For persons who do not like the planned exercise or feel unable to do so, can also prove very useful to reduce time spent on sedentary activities like watching television. Simply standing for one hour a day, instead of sitting watching television, would involve an expenditure equal to 1 or 2 kgs of fat per year. For all areas of the body to the maximum benefit, it is also necessary number of specific strengthening exercises and stretching. This is especially important in older people.
The recommendation to perform moderate exercise does not negate the fact that the most intense are more beneficial, especially because they improve heart health and glucose metabolism. But most people need several months to reach these levels.
The recommendations of the Quebec Declaration on Physical Activity, Health and Welfare (Quebec státem Consensus on Physical Activity, Health and Well-Being) provide useful guidelines on physical activity.
Summary of recommendations of the Consensus Statement on Quebec
Physical Activity, Health and Welfare (1995)
- Mobilize large muscle groups to be more than a normal load
- Require a minimum total of 700 kcal / week
- Be performed regularly and if possible daily
In practice, a continuous rhythmic exercise such as walking to for 20-30 minutes a day would be sufficient to meet these requirements in most adults.
To achieve maximum benefits for health, activities should:
- Include periods of intense activity
- Include a variety of activities
- Exercise most of the muscles of the body, including the trunk and upper body
- Assume a cost of up to 2000 kcals / week
- Keep lifetime
When people become more active, reduce the risk that they might suffer from heart disease, some cancers and diabetes, and can better control their weight, increase endurance for physical work and improve health of muscles and bones. They also have more opportunities to improve their quality of life and psychological health. Physical activity cannot only add years of life, but adds quality of life for those years.
Sedentariness is an epidemic across Europe. The leading authorities from around the world have accepted the evidence linking life with inactive disease and various physical and mental disorders. At the moment, it seems that the situation is rather worse. The costs in terms of human suffering, lost productivity and health care are high. The solution is simple. We need to move more and more frequently. But unfortunately, it is difficult for most people, especially those who stand to benefit most, such as middle-aged adults and the elderly become more active, if not taken any action.
To promote physical activity is required concerted action of several agencies that help people reduce their sedentary lifestyle and increase the performance of physical activities, and change the environment for empowering the people to be more active. National governments, regional and local authorities must work more closely with urban planners and transport planners, schools, workplaces and health authorities to encourage more activities such as walking, biking and sports activities. In turn, each person is responsible for reviewing and re-evaluating their priorities, to lead a lifestyle that includes more physical activity a day.
1. Andersen, LB, Schnor, P., Schroll, M., & Hein, HO (2000). All-cause mortality associated with Physical activity during leisure time, work, sports, and cycling to work. Archives of Internal Medicine, 160, 1621-1628.
2. Biddle, S.J.H., Fox, K.R., & Boutcher, S.H. (2000). Physical activity and psychological well-being. London: Routledge.
3. Bijna, FC, Feskens, EJ, Caspersen, CJ, Nagelkerke, N., Mosterd, WL, & Kromhout, D. (1999). Baseline and Previous Physical activity in relation to mortality in elderly men: the Zutphen Elderly Study. American Journal of Epidemiology, 150, 1289-1296.
4. Medicine and Science in Sports and Exercise (1999), Nov, 31 (11 Supplement).
5. Blair, s.n. & Hardman, A. (1995). Special issue: Physical activity, health and well-being - an international scientific consensus conference. Research Quarterly for Exercise and Sport, 66 (4).
6. Fogelholm, M., Kukkonen, M., & Harjula, K. (2000). Does Physical activity prevent weight gain: A systematic review. Obesity Reviews, 1, 95-111.
7. Lawlor, D. A., & Hopker, S. W. (2001). The effectiveness of exercise as an intervention in the management of depression: systematic review and meta-regression analysis of randomized controlled trials. British Medical Journal, 322, 1-8.
8. Prentice, AM, Jebb, SA (1995). Obesity in Britain: Gluttony or Sloth. British Medical Journal, 311, 437-439.
9. Sports Council and Health Education Authority. (1992). Allied Dunbar National Fitness Survey. London: Sports Council / HEA.
10. U.S. Department of Health and Human Services (PHS). (1996). Physical activity and health. A report of the Surgeon General (Executive Summary). Pittsburgh, PA: Superintendent of Documents.