to the editor: We enjoyed reading the article "Counseling for Physical Activity in Overweight and Obese Patients."1 We would like to make some further observations. The prevalence of obesity and being overweight is significantly higher in the United States compared with Spain, where the prevalence of obesity among persons 25 to 60 years of age is 13.3 percent for men and 15.7 percent for women.2 However, the particular problem of a lack of exercise counseling by health professionals seems to be similar in these two countries. In a nonpublished, community-based, cross-sectional survey conducted in 2002 in our Family Medicine Teaching Unit, we found that fewer than 36 percent of the 481 adult subjects interviewed received counseling on physical activity from their primary care physician. This resulted in fewer than 21 percent of the subjects increasing their amount of exercise.
Because many clinical practice guidelines recommend physical activity for patients who are obese, even when they do not lose weight, the optimal intensity level will depend on the patient's objectives. If, as the authors state,1 the patient is searching for weight reduction then the emphasis should be on increasing duration rather than intensity to optimize caloric expenditure. If the patient is searching to improve cardiovascular fitness, exercise should be performed at a certain intensity threshold. Different studies have determined this threshold: the Institute for Aerobics Research2 established a fitness threshold of 10 metabolic equivalents (METs) oxygen consumption for men and 9 METs for women; the Harvard study3 set a caloric expenditure threshold of at least 1,500 extra calories for physical activity per week. This implies the need to report the prevalence of active and nonactive people, and to quantify and analyze their level of activity.
It is surprising how infrequently an intervention with such a positive cost-benefit effect is implemented in general practice. Some authors4 in Spain try to explain this situation with the following reasons: lack of formal training in health professionals; busy practice; inadequate institutional support; little interest in research; lack of coordination between health professionals and physical activity specialists; and lack of support from mass media. Research and promotion campaigns should be encouraged if physicians want to achieve the goals presented in the article by McInnis and colleagues.1