Physical activity

Physical activity is important for health

The levels and patterns of physical activity in a population comprise an important generic indicator in Public Health Nutrition. Physical inactivity, usually together with unhealthy food habits, is associated with the development of many of the major non-communicable diseases and conditions in society, such as cardiovascular disease, some cancers, obesity, diabetes and osteoporosis. It has become increasingly clear that physical inactivity is a global health issue (Sjöström et al., 2003).

Physical Activity is any movement, using energy above resting level

Physical activity is defined as any bodily movement produced by skeletal muscles that results in energy expenditure above resting level (Caspersen et al., 1985). This broad definition involves virtually all types of activity like: walking, cycling, dance, traditional games, pastimes, gardening, housework, sports and intentional exercise (Cavill et al., 2006). Oppositely, inactivity refers to a state of no marked increase in energy expenditure above resting level (Hagströmer, 2007). Sedentary lifestyle includes some activity, but usually not enough for gaining health effects (Sjöström et al., 2006), while active living is a way of life that integrates at least half an hour of physical activity each day into daily routines (Cavill et al., 2006). See also: Graphical description of the definition of physical activity and related concepts.

Health Enhancing Physical Activity is any form of activity that benefits health

Health Enhancing Physical Activity is any form of physical activity that benefits health and fitness without undue harm or risk (Foster, 2000). This can be all daily activities and can, but does not necessarily, include sports. Not all physical activity is beneficial for health (Hagströmer, 2007). To be beneficial for health, physical activity should be ‘moderate’ or ‘vigorous’:

• Moderate-intensity physical activity raises the heart-beat and leaves the person feeling warm and slightly out of breath. It increases the body’s metabolism to 3-6 times the resting level (3-6 MET ’s) (Cavill et al., 2006). Brisk walking, for example, has an equivalent of 4.5 MET’s (Ainsworth et al., 2000).
• Vigorous-intensity physical activities enable people to work up a sweat and become out of breath. They usually involve sports or exercise, like running or fast cycling. They raise the metabolism to at least six times its resting level.

Physical fitness is the result of a physical active life

Physical fitness is defined as the ability to carry out daily tasks with vigour and alertness, without undue fatigue and with ample energy to enjoy leisure-time pursuits and to meet unforeseen emergencies. Next to physical activity, physical fitness and a few related indicators have been proposed as indicators to be used in the European Health Monitoring System (Sjöström et al., 2003). For more information on these indicators, see Indicators proposed for the European Health Monitoring System.

About 29% of the European population is sufficiently physical active

Across EU Member States, only 29% of the population shows ‘sufficient physical activity’, according to current guidelines. Percentages range from over 40% for the Netherlands and Germany to 23% in Sweden. This was reported from the 2002 Special Eurobarometer Wave 58.2, using the International Physical Activity Questionnaire (IPAQ). Approximately 1,000 individuals were interviewed in each of the EU-15 countries (Sjöström et al., 2006). See Health-enhancing physical activity, sedentariness, walking and sitting across EU-15 countries and Sufficient total activity by country in the EU-15. For more information on how ‘sufficient physical activity’ is calculated, see Operationalisation of sufficient physical activity.

Only few international comparisons of physical activity exist

The 2002 Special Eurobarometer is one of the few examples of internationally comparable data on physical activity. The collection of such data has only been developed over the past few years (Cavill et al., 2006). Also, internationally agreed survey instruments to measure physical activity are in ongoing development (WHO, 2002d). For more details on development of harmonised data see Consensus process for measuring physical activity started in June 2006.

National data are available, but not comparable

National data on physical activity are available for several countries, but they are usually based on different survey questions or theoretical concepts. Also the periods of data collection are not similar (Elmadfa & Weichselbaum, 2004). Therefore, these data cannot be compared between countries. The European Nutrition and Health Report 2004 listed some examples of national data on physical activity:

In Austria, physical exercise 3 times per week or more was higher in men living in Vienna compared to men living in Federal states (37% versus 19%). No such difference was reported for woman (38% in Vienna versus 41% in Federal States). The survey asked for the frequency of exercise among adults.

In Finland, physical exercise at least 2 times per week was reported between 49% and 69% for various age groups (2003). Men were slightly less active than women in all age groups but one. Finland has a long tradition in assessing levels of regular physical exercise.

In France, about 52% of adult men were reported to walk more than 1 hour per day or perform equivalent activities, compared to 38% in women. But these data were derived from a non-representative sample.

In Germany, the percentage having ‘no leisure time exercise at all’ was lower (43.8%) for men than women (49.5%). The percentage of men that exercise at least 2 hours per week was higher (23.5%) than the percentage of women (15.4%). These data were reported for adults aged 18–79 years.

Internationally comparable data on physical fitness are not available

Cardiorespiratory fitness has been suggested to be included in the European Health Monitoring System for both children and the adult population, but as for now, international comparable data are not available (Ruiz et al., 2006a; Ruiz et al., 2006b; Sjöström et al., 2003). Although efforts are being made in order to standardize and improve the assessment in Europe, for example in the ALPHA study. See also Indicators proposed for the European Health Monitoring System.

Physical activity enhances health and reduces disease risk

Physical activity has beneficial effects on many aspects of health and reduces the risk of a variety of chronic conditions. Physical activity improves physical fitness, psychological well-being and musculoskeletal health (strengthening bones and joints). It enhances the functioning of the immune system, cognitive functioning and the general quality of life (Cavill et al., 2006; Bull et al., 2004). It reduces the risk of heart disease, overweight, diabetes and cancer, and prevents symptoms of depression, anxiety and stress (WHO, 2002d). Older people gain benefit from participation in physical activity in maintaining strength and flexibility. This helps them helps continue to perform daily activities and reduces risk of falls and hip fractures (Cavill et al., 2006).

A physically active lifestyle exerts positive effects on communities and societies

Next to health benefits, there are positive effects to communities and societies associated with an active lifestyle. WHO reports the following (Cavill et al., 2006):

• opportunity to interact with others, the community and the environment;
• chance to develop new skills and meet new people;
• may help to reduce levels of crime and antisocial behaviour;

Most importantly, physical activity is associated with other positive health behaviour (e.g. healthy eating and non-smoking), and mediates other behavioural change as well (Cavill et al., 2006).

Physical activity reduces the risk of cardiovascular diseases

Appropriate levels of physical activity reduce the risk of cardiovascular diseases and diabetes by improving glucose metabolism, reducing body fat and lowering blood pressure, next to other mediating mechanisms (WHO, 2002d). Strong evidence indicates that: inactive people have up to double the risk of heart disease compared to active people; physical activity prevents stroke and improves many CVD-associated risk factors, such as high blood pressure and high density cholesterol levels (Cavill et al., 2006). The World Health Report 2002 estimates that physical inactivity causes about 22% of cases of ischaemic heart disease globally (WHO, 2002d).

Physical activity reduces the risk of some cancers.

The overall risk of cancer can be reduced by physical activity (Cavill et al., 2006; WCRF & AICR, 2007). There is convincing evidence that physical activity reduces the risk for specific forms of cancer. See table 1..

Physical activity is a major factor in controlling overweight and obesity and lowers the risk of type 2 diabetes

Physical activity also is a factor in controlling overweight and obesity. Overweight and obesity occur when energy intake exceeds energy expenditure. Habitual, lifetime physical activity can reduce weight gain. Appropriate levels of activity can support healthy weight maintenance or even weight loss, which is important for people who are already overweight or obese (Cavill et al., 2006). Additionally there is strong evidence that moderate/vigorous physical activity reduces the risk of type 2 diabetes by about 30% compared to inactive people (Cavill et al., 2006).

Being fit when young relates to a healthy cardiovascular profile when older

There is evidence indicating that the level of cardiorespiratory fitness during childhood and adolescence is associated with the level of fitness in adulthood (Ruiz et al., 2006a). Findings from prospective cohort studies suggest that a low cardiovascular fitness during childhood and adolescence is associated with cardiovascular risk factors later in life, such as hyperlipidemia, hypertension and obesity. Also at young age, children and adolescents with higher levels of cardiovascular fitness have a more favourable cardiovascular profile (i.e. lower levels of cholesterol, triglycerides, insulin, blood pressure, and body fat) compared with their unfit counterparts. The latter is shown by a number of cross-sectional studies.

Inactivity might cost a country about €150-300 per citizen per year

WHO has reported estimates of the annual economic costs of inactivity in England (including those to the health system, days of absence from work and loss of income due to premature death) to be €3–12 billion. This excludes the contribution of inactivity to overweight and obesity. Overall, economic cost of obesity and overweight might run to €9.6–10.8 billion per year. For Switzerland the annual cost of inactivity has been estimated at €1.1–1.5 billion. Based on these estimates, physical inactivity might cost a country about €150-300 per citizen per year. It should be emphasized that these are rough estimates and that, due to many methodological problems, such studies are scarce (Cavill et al., 2006; Fox, 2003).

The urban environment is a very important factor influencing physical activity

The urban built environment and daily transport are among the most important barriers or promoters of daily physical activity. Possible traffic accidents can be a powerful reason for parents to not allow children to walk or cycle to school or play outdoors, especially in urban settings. In the UK, children from lower social classes are five times more likely to be killed on the road than those from higher classes. The underlying reason is that poorer children are more likely to live in urban areas with poor road safety and high-speed traffic (Cavill et al., 2006). Prevention strategies should focus on safe urban environments, to enable citizens to gain the positive effects of physical active life (Cavill et al., 2006). See table 1.

Table 1: Promoters and barriers of physical activity in urban areas (Cavill et al., 2006)

Especially the transport sector can strongly influence opportunities to be physically active, both by facilitating walking and cycling and by enabling people to get to places to be active (Cavill et al., 2006).

Socioeconomic conditions affect physical activity

Socioeconomic circumstances can affect physical activity in several ways. Poorer people have less free time, poorer access to leisure facilities or living environments that do not support physical activity (Cavill et al., 2006).

Workplace conditions influence physical activity

Workplace conditions influence the amount of physical activity people have during work. Adults spend a great part of their waking time per day at the workplace, but perform in general very little physical activity during this time. The proportion of people who declared that they perform a lot of physical activity at work varies from 10% in Malta and Italy to 27% in Poland, the Netherlands and Lithuania (EC, 2007c). See People with a lot of physical activity at work by country in the EU-27. However, the workplace is reported to have a great potential to increase daily physical activity, if workplace conditions be modified to be more supportive (Cavill et al., 2006).

Personal factors influence physical activity

Although they are less influential than environmental factors, personal and psychological factors play are role in a physical active life as well. See table 2 (Cavill et al., 2006).

Table 2: Promoters and barriers of physical activity from personal and psychological factors

EU action stated in the Strategy for Europe on Nutrition, Overweight and Obesity

The White Paper A Strategy for Europe on Nutrition, Overweight and Obesity related health issues outlines an integrated approach for Europe to improve healthy nutrition and physical activity (EC, 2007b). It addresses the policy coherence at four levels:

• community level, especially encouraging physical activity by supporting the improvement of infrastructure in terms of walking and cycling pathways as well as urban transport plans;
• member state level;
• the private sector, especially encouraging sport organisations to work together with the public health organisations, development of healthy lifestyles in the workplace, clinical professional bodies to strengthen training of health professionals with regard to nutrition and physical activity; and
• international cooperation, especially to develop a nutrition an physical activity surveillance system for the EU-27 together with WHO.

European Platform aims to collect intervention experiences and good practice

The European Platform for Action on Diet, Physical Activity and Health aims to collect intervention experiences and models of good practice. It runs a database of examples of best practice. At the start of 2008, 69 initiatives or activities to improve physical activity have been listed in the database. The European Platform was founded in March 2005 and provides a common forum for interested actors. Currently, the platform has 34 member organisations, ranging from food industry to consumer protection NGOs.

WHO’s Global Strategy outlines principles and responsibilities for action

The Global Strategy on Diet, Physical Activity and Health of 2004 outlines goals, objectives and evidence, as well as principles and responsibilities for action (WHO, 2004g). Most detailed is the list of policies and actions to be implemented at member state level. Next to the strategy, a comprehensive framework of indicators to monitor the implementation of the Global Strategy at member state level has been published by WHO (WHO, 2006e).

General recommendations for physical activity from WHO

WHO Global Strategy on Diet, Physical Activity and Health states one of the most general recommendations for physical activity: […] It is recommended that individuals engage in adequate levels [of physical activity] throughout their lives. Different types and amounts of physical activity are required for different health outcomes: at least 30 minutes of regular, moderate-intensity physical activity on most days reduces the risk of cardiovascular disease and diabetes, colon cancer and breast cancer. Muscle strengthening and balance training can reduce falls and increase functional status among older adults. More activity may be required for weight control (WHO, 2004g).

To which activities these recommendations correspond per age group is illustrated in How people of all ages could reach the recommended levels of physical activity. Several similar recommendations have been developed and issued over the years by different authors or authorities: see Physical activity recommendations for an overview (Hagströmer, 2007).

Several international networks are set up to promote physical activity

European and international networks were set up to promote physical activity. These networks were setup by public health and scientific bodies. See Relevant databases, projects and organisations for more information.

A broad range of national and European examples of interventions exist

National and European examples of interventions are multifaceted in number and approach. In many European member countries interventions can be found. Some European examples are the Shape Up Programme, the Keep Fit Programme and Move for Health. More information is in the database of the European Platform for Action on Diet, Physical Activity and Health as well as at the HEPA Europe webpage.

The figure refers to the time spent awake. The sizes of the different circles are not proportional to time spent at different levels.

Indicators proposed for the European Health Monitoring System

Physical activity and Health-related fitness have been proposed as indicators for the European Health Monitoring System. Their descriptions below are taken from ‘Making way for a healthier lifestyle in Europe’, the summary report of the project ‘Monitoring Public Health Nutrition in Europe’ (Sjöström et al., 2003).

Indicator: Physical Activity Level and Pattern

Suggested operational measures for this indicator:

• Total amount of activity expressed either as activity energy expenditure (kcal, Joules, MET mins, etc) or physical activity level (PAL);
• PAL: Time (mins/day or week) spent at health enhancing physical activity level (i.e. activity at moderate and vigorous intensity levels);
• Time (mins/day or week) spent sitting;

Justification for this indicator: Physical activity is a complex behaviour. Any activity can be described in terms such as intensity, frequency and duration, and these dimensions must be considered. An assessment methodology should also consider inactivity, such as time spent sitting. Physical activity can be related to work, transportation, home and leisure time. The activities at either of these domains may have specific health consequences, and advanced monitoring should also consider these.

Indicator: Health-related Fitness

This concept can be operationalized in different ways. Physical fitness can be thought of as an integrated measure of most, if not all body functions (musculoskeletal, cardiorespiratory, circulatory, psychoneurological, endocrine-metabolic) involved in the performance of daily physical activity and/or physical exercise. Hence, when physical fitness is tested, the functional status of all these systems is actually being checked. Health-related physical fitness, refers to those components of fitness that are affected favorably or unfavorably by physical activity habits and relate to health status (Ruiz et al., 2006b).

Operationalization: Maximal Aerobic Capacity. This can be done by the 2km UKK Walk Test as a population assessment of cardiovascular fitness (aerobic fitness/maximal aerobic power) and is named as the golden standard.

Justification for this indicator: It is well suited for the assessment of health-related fitness among the general population. It also reflects the functional capacity of the musculo-skeletal system.

Operationalizations: Bodily Control, Muscular Strength, Joint Mobility. Tests to measure these fitness components have been defined within the EUROFIT project. A new consensus test battery is in development by the ALPHA project.

Justification for monitoring muscular strength:The role of muscular strength in the performance of activities of daily living and exercise, as well as in the prevention of chronic disease is increasingly being recognized. Resistance exercise training increases muscular strength, and is currently prescribed by major health organizations for improving health and fitness. It provides strong and independent prognostic information about the overall risk of illness and death in both men and women across a broad spectrum of ages.

Consensus process for measuring physical activity started in June 2006

Based on earlier attempts for harmonisation, such as EUROFIT, EUPASS, IPAQ, and WHO GPAQ, a new consensus process for instruments to assess physical activity started in June 2006. In order to measure how active European citizens are and how much it benefits their health, standardised instruments are needed. In people’s day-to-day life, there are four domains, which provide opportunities to be physically active: at work, for transport, in domestic duties, or in leisure time (WHO, 2002d). Furthermore, 4 characteristics of people’s activity need to be measured in order to estimate the resulting health benefits: frequency, intensity, time and type of activity.

Questionnaires are the most cost-effective measuring method

Questionnaires are a cost-effective, but subjective way of assessing the characteristics of peoples activity. Mainly 2 initiatives developed questionnaires in the last decades: (1) the International Physical Activity Questionnaire (IPAQ, initiated by a consortium of scientific and health institutions around the world) and (2) the Global Physical Activity Questionnaire (GPAQ, as part of WHO’s Global Physical Activity Surveillance activity, especially in developing countries), which derives from IPAQ. Difficulties in applying questionnaires in a standardized manner arise from differing cultural and linguistic backgrounds (e.g. the translation process or cognitive testing of which meaning is associated with the questions) as well as the difficulties in administering questionnaires to different age groups (e.g. answers from children seem to be much less reliable). Furthermore, domain specific questions for assessing the activity promoting or preventing characteristics of the built environment, for assessing physical activity at the work place as well as during daily transportation need agreement.

Accelerometers and health related fitness tests are an objective measurement method

Accelerometers are an objective measurement, using small devices comparable to common pedometers for monitoring people’s vertical movements (by walking, running, etc.) over days or weeks. With decreasing costs of these devices in the last decade, accelerometry develops as a useful alternative to questionnaires (EC, 2007b).

Health-related fitness tests are also an efficient way of assessing people’s fitness and a consensus about which test is most reliable and feasible in large samples needs to be accomplished.

Data collection and interpretation need to be standardized

To gain comparable data, for all these instruments and options, data collection and interpretation routines need to be standardized and subsequently applied. The project Assessing levels of phyiscal activity and fitness (ALPHA) with involvement of the European Commission, WHO, CDC and academic centres around the world started this consensus process in June 2006.

Operationalisation of sufficient physical activity

A sufficiently active person is one that meets at least the current guidelines of physical activity. In the Eurobarometer 2002, the International Physical Activity Questionnaire (IPAQ) has been used. The questionnaire is asking for daily activity habits. During operationalisation, the answers to the questionnaire are translated into metabolic equivalents using a scoring protocol. Aim of this operationalisation is to summarise the qualitative with the quantitative parts of information of daily physical activity habits and compare them against the public health recommendations of sufficient physical activity. In the Eurobarometer 2002 study, the cut point for sufficient total activity was:

• 3,000 MET minutes per week accumulated over 7 days; or
• 1,500 MET minutes of vigorous-intensity activity accumulated over 3 days.

It represents 5×30 minutes of moderate or 3×20 minutes of vigorous on top of a basal 60 min of moderate activity per day.

Ischaemic heart disease

Diabetes

Health Inequalities

Overweight

Breast cancer

Blood pressure

Eurobarometer

Eurostat

WHO Global InfoBase

Health-EU Portal, sports & leisure

Diet, Physical Activity and Health - EU Platform for Action

GPAQ, WHO Global Physical Activity Surveillance

EHSS European Health Survey System

HEPA Europe, European network for the promotion of health-enhancing physical activity

IPEN International Physical Activity and the Environment Network

ISBNPA International Society for Behavioral Nutriton and Physical Activity

GSHS Global School-based Student Health Survey

HBSC, WHO Health Behaviour in Schoolaged Children

ENHR II, European Nutrition and Health Report 2009

ALPHA Assessment of Level of Physical Activity and Fitness

IPAQ International Physical Activity Questionnaire

HELENA Healthy Lifestyle in Europe by Nutrition in Adolescence

CINDI Countrywide Integrated Noncommunicable Diseases Intervention programme

IDEFICS Identification and prevention of dietary- and lifestyle-induced health effects in children and infants

FINBALT Health Monitor

AVENA, Food and Assessment of the Nutritional Status of Adolescents

EUNAAPA European Network for Action on Ageing and Physical Activity

EUPASS European Physical Activity Surveillance System

European Nutrition and Health Report

Monitoring Public Health Nutrition in Europe

PANACEA Physical Activity, Nutrition, Alcohol, Cessation of Smoking, Eating out of home And obesity

Percentage of people undertaking health-enhancing physical activity, sedentariness, walking and sitting across EU-15 countries

Percentage of people undertaking sufficient (total) physical activity in selected countries in 2002 (interactive)

Percentage of people undertaking 'a lot of physical activity' at work (in the last 7 days) in selected countries in 2005 (interactive)

Attributable DALYs due to physical inactivity for ischaemic heart disease, ischaemic stroke, type II diabetes, colon cancer and breast cancer