According to a recent meta-analysis1 of physical activity and fitness as separate risk factors for cardiovascular disease, the relative risk of cardiovascular disease declines as the percentile of both activity and fitness increases, with the greatest reduction in risk appearing in association with increases in physical fitness. This means that leisure time physical activity needs to reach a certain threshold in order to improve physical fitness and avoid cardiovascular disease. Data from a study by the Institute for Aerobics Research (in Dallas)2 show that for fitness to be attained, this threshold could occur at a maximum oxygen consumption of 35 ml/kg/min (10 METs) in men, and 31.5 mg/kg/min (9 METs) for women. For physical activity, a study of Harvard students3 found that the threshold occurs at a leisure time calorie expenditure of 1500 kilocalories/week or more.
To determine the prevalence of sedentary lifestyles for a given population, it is not enough to find out who is active and who is inactive. Instead, activity needs to be quantified, and a cutoff point which reflects this threshold
needs to be determined. Recent studies of physical activity and cardiovascular or coronary disease in women4 and men5 have shown that the intensity of exercise, which guarantees improved physical fitness, is important to prevent cardiovascular problems.
To increase activity levels or physical fitness, groups of experts in prevention in developed countries began to propose that health counseling be provided in the course of visits to the doctor. The year 1995 saw the start of the PACE project in the USA (Physician-based Assessment and Counseling for Excercise).6 This program postulated that changes toward healthier behaviors take place in stages (Pochaska´s transtheoretical model) that require different interventions depending on which stage the patient is in. The study titled «Attitudes and practices regarding physical activity: situation in Spain with respect to the rest of Europe» provides valuable information on the size of the population that we might expect to find in each stage of change. However, it differs from the PACE study in a fundamental way regarding the number of stages in the process of change. The PACE project considered only three stages: precontemplation (not active or with no intention of becoming active), contemplation (little or no activity but with the intention of becoming more active) and activity (regular physical activity in an amount and intensity sufficient to prevent cardiovascular disease). These stages reflect three situations that physicians can encounter in their practice: sedentary patients, partially active patients whose level of activity is insufficient to promote health or prevent disease, and patients who are sufficiently active. Interventions were thus reduced to advice to think about changing lifestyle (precontemplators), advice to increase levels of physical activity above no activity or above the level of activity currently being practiced (contemplators), or advice aimed at reinforcing and maintaining the behavior (active patients). In the above mentioned study of attitudes and practices, however, a larger number of stages of change was used; this would necessitate more types of intervention or simplification by combining stages for which the same type of advice could be given.
The usefulness of this study for primary care can be distilled in the following points. The results constitute a call to primary care health professionals to use patients´ visits as an opportunity to encourage patients to progress through successive stages in the process of changing their physical activity habits, so that Spain can catch up with and surpass other European Union countries. This enterprise, however, will also require population-targeted media campaigns sponsored by local and national health administrations. Also needed are data that will: a) give primary care health professionals an idea of which segment of the population they should direct their health counseling efforts to with the aim of increasing levels of physical activity, and b) enable them to estimate how much time they will need. Finally, information is needed about the stages in the process of change where Spain lags furthest behind other EU countries, so that efforts can be targeted to favoring progress through successive stages.
One of the main conclusions of the study is that the proportion of individuals with a poor attitude toward changing their level of physical activity is greater in Spain than the mean for the entire EU. Possible reasons for this may be found in a doctoral dissertation titled «Promoting physical activity in Catalonian primary care centers,»7 prepared for a PhD degree in physical education and sports. The main conclusions of this study bear repeating here: a) health personnel lack formal training in the promotion of physical activity, and circumstances surrounding visits to the health center are not conducive to efforts to promote exercise; b) efforts to promote physical activity do not take into account differences between patients in their individual needs and circumstances; c) institutional support for the promotion of physical activity is inadequate, because it is not perceived to be cost-effective; d) research on the promotion of physical activity is scarce because funding agencies do not consider this an area of high priority; e) lack of coordination hampers efforts by health professionals and physical activity specialists to work together; f) physical activity specialists have yet to find their own space in the professional interface between health care and physical activity; g) undergraduate training for the health professions includes no formal teaching in the promotion of physical activity, and h) messages transmitted via the media center on «performing better than the rest» or «being the best», rather than on promoting increased physical activity for the population as a whole.
Lines of research that should be pursued in the light of this study might aim to test different types of counseling adapted to different stages of change, to show whether such counseling helps patients progress toward the maintenance of adequate levels of leisure-time physical activity. The PREPAF project (Programa Experimental de Promoción de la Actividad Física, or Experimental Program for the Promotion of Physical Activity), now in progress in the province of Biscayne (Northern Spain), will attempt to show that under the usual conditions of visits to primary care physician, two different types of counseling -- for patients who are «unprepared» (i.e., in the precontemplative state) or «prepared» (i.e., in the contemplative state) -- are sufficient to increase levels of physical activity or enable patients to progress to the next stage of change. This project has been presented to the Preventive Activities and Health Promotion Research Network, and other participating centers in the network are expected to join the project.