Various Types of Physical Activity

If physical activity is important for reducing the negative health impact of various chronic diseases, then which type of physical activity should a physician recommend to the patient? There are three categories of physical activity to consider: work-related, leisure-time physical activity (LTPA), and lifestyle activity.

The possible answer to helping reduce the prevalence of obesity, according to a study by Gutierrez-Fisac et al., may not be found in the workplace. His study was based on data from the 1993 Spanish National Health Survey, which contained a sample of 12,044 Spanish men and women aged 20 to 60 years. The mean BMI was greater for those who were inactive during their leisure time (BMI 25.9 in men, 24.43 in women) compared to those who participated in vigorous activity (men 24.42, women 22.97). The odds ratio (OR) for obesity decreased with increasing level of leisure-time activity in both men (OR 0.64) and women (OR 0.68). However, neither the mean BMI nor the percentage of obesity varied significantly with respect to the amount of work-related physical activity [24]. It is not clear to what extent how much total caloric intake in relation to the level of work-related physical activity (WRPA) played a role in these results. It might be that the more physically demanding the work, the more calories the individual consumes, which offsets calories utilized as a result of the work.

Leisure-time physical activity is typically defined as total weekly energy expenditure as expressed in metabolic equivalent-hours (MET-h), with 1 MET-h equal to sitting in a chair for 1 hour. Moderate activity (<6 MET-h) includes walking, working outdoors, and weightlifting. Vigorous LTPA (>6 MET-h) includes jogging, biking, swimming laps, racquetball, and rowing [25].

The health benefits of LTPA are clear. As mentioned in the study by Gutierrez-Fisac et al., LTPA had an inverse relationship to BMI. The higher the intensity level of LTPA, the lower the BMI was for both genders [24]. LTPA also has numerous other health benefits, including an inverse relationship with development of atherosclerosis of the carotid arteries [26]; reduction in C-reactive protein, interleukin-6, and tumor necrosis factor; and improved sensitivity to insulin [25].

However, some patients may not have the financial resources for membership in a fitness club; others may not feel comfortable being in the presence of members who are not obese. Still other patients may not live in a neighborhood where it is safe to walk or may not have home fitness equipment. In other words, is structured PA essential for a patient to receive the health benefits of PA?

A randomized study involving 235 participants compared a structured PA intervention to a lifestyle PA intervention over 24 months. The structured PA intervention consisted of a personal trainer at a fitness center up to 5 days per week. The lifestyle PA intervention arm recommended that participants accumulate at least 30 minutes of moderate-intensity PA on 5 days, and preferably all days, of the week. Participants also met in small groups 1 hour a week for the first 16 weeks and learned cognitive and behavioral strategies to increase physical activity. Both groups experienced a comparable increase in CRF from baseline, a decrease in both systolic and diastolic blood pressures, and a reduction in percentage of body fat [27]. Weight loss was not an outcome measure of the study, and in fact neither group lost weight.

In terms of weight loss, is there a difference between lifestyle activity and a structured PA program? In a small study of 40 obese women, Andersen et al. examined the effects of lifestyle activity versus structured aerobic exercise in obese women (mean BMI 32.9). Both groups followed a low-fat diet. The structured PA group participated in supervised aerobic classes. The lifestyle PA group was encouraged to have 30 minutes of moderate-intensity exercise most days of the week, and to incorporate more physical activity during routines of daily living. Members were given an accelerometer to provide feedback on activity level [28]. The results showed that the mean weight loss between the two groups was similar throughout the study, with a divergence occurring with duration of time (Figure 4.3).

For many obese patients, scheduled exercise is not appealing or possible for a variety of reasons. The results of these two studies suggest that increasing lifestyle physical activity can provide health benefits equal to a structured exercise program. These results should encourage the physician that patients receive important health benefits simply by trying to do some moderate exercise 5 days per week and by increasing the physical activity of their daily living like parking farther away from entrances to stores or taking the stairs instead of the elevator.

Week

Figure 4.3. Mean changes in body weight for the diet plus lifestyle group and diet plus aerobic group. (Reprinted with permission from Andersen RE, Wadden TA, Bartlett SJ, et al. JAMA January 27, 1999, vol. 281 (no. 4): 337. Copyright © 1999, American Medical Association. All rights reserved.)

Week

Figure 4.3. Mean changes in body weight for the diet plus lifestyle group and diet plus aerobic group. (Reprinted with permission from Andersen RE, Wadden TA, Bartlett SJ, et al. JAMA January 27, 1999, vol. 281 (no. 4): 337. Copyright © 1999, American Medical Association. All rights reserved.)

Dieting Dilemma and Skinny Solutions

Dieting Dilemma and Skinny Solutions

The captivating thing about diets is that you don't get what is researched or predicted or calculated but rather, you get precisely what you expect. If the diet resonates with you then it will likely work, if it doesn't resonate, it won't.

Get My Free Ebook


Post a comment