Lifetime physical activity in postmenopausal Caucasian and Chinese-Canadian women
ABSTRACT Physical activity is recognized as a modifiable lifestyle risk factor that may prevent breast cancer. The aim of this cross-sectional study was to compare the physical activity patterns in two populations with different risks for breast cancer. We collected physical activity information from two groups of postmenopausal Canadian women with substantially different risks of developing breast cancer - Caucasians (N=372) and recent Chinese migrants from urban China (N=352). The frequency, duration, and intensity of occupational, household, and recreational activities were measured throughout the lifetime using the interviewer-administered Lifetime Total Physical Activity Questionnaire. Compared with Caucasians, Chinese migrants reported lower average total physical activity over their lifetime and for each age period (0-21, 21-29, 30-39, 40-49, and ≥50 years). Compared with Caucasians, Chinese migrants reported greater lifetime occupational activity, but lower levels of lifetime activity for both household and recreation activity. Among Chinese migrants, reported levels of occupational, household, and recreational activities were all greater in migrants from Mainland China than in migrants from Hong Kong. In conclusion, our results show that total activity was greater amongst Caucasians than Chinese migrants, suggesting that the lower breast cancer risk in urban Chinese women is not likely to be explained by greater total physical activity.
SourceAvailable from: vucutanalizi.com[Show abstract] [Hide abstract]
ABSTRACT: A coding scheme is presented for classifying physical activity by rate of energy expenditure, i.e., by intensity. Energy cost was established by a review of published and unpublished data. This coding scheme employs five digits that classify activity by purpose (i.e., sports, occupation, self-care), the specific type of activity, and its intensity as the ratio of work metabolic rate to resting metabolic rate (METs). Energy expenditure in kilocalories or kilocalories per kilogram body weight can be estimated for all activities, specific activities, or activity types. General use of this coding system would enhance the comparability of results across studies using self reports of physical activity.Medicine & Science in Sports & Exercise 02/1993; 25(1):71-80. DOI:10.1249/00005768-199301000-00011 · 4.46 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Recent efforts to more fully understand the mechanisms through which work and family experiences and their cross-over effects influence well-being have stimulated the development of integrative models of the work-family interface. This line of research is represented by the model which Frone, Russell, and Cooper (1992) tested with a sample of U.S. employees. In the current study, we examine the cross-cultural generalizability of this model among married Hong Kong employees. Results of the analyses suggest that many of the relationships among work and family constructs are similar across the two cultures, but that the nature and effects of the cross-over between family and work domains on overall employee well-being may differ. That is, life satisfaction of Hong Kong employees is influenced primarily by work-family conflict, while that of American employees is influenced primarily by family-work conflict. Limitations of the study and implications of the findings for assisting employees integrate their work and family responsibilities as a source of competitive advantage are discussed.Journal of Management 01/1999; 25(4):491-511. DOI:10.1177/014920639902500402 · 6.86 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: To review (1) the epidemiological literature on physical activity and the risk of breast cancer, examining the effect of the different parameters of activity and effect modification within different population subgroups; and (2) the biological mechanisms whereby physical activity may influence the risk of breast cancer. A review of all published literature to September 2007 was conducted using online databases; 34 case-control and 28 cohort studies were included. The impact of the different parameters of physical activity on the association between activity and the risk of breast cancer was examined by considering the type of activity performed, the timing of activity over the life course and the intensity of activity. Effect modification of this association by menopausal status, body mass index (BMI), racial group, family history of breast cancer, hormone receptor status, energy intake and parity were also considered. Evidence for a risk reduction associated with increased physical activity was found in 47 (76%) of 62 studies included in this review with an average risk decrease of 25-30%. A dose-response effect existed in 28 of 33 studies. Stronger decreases in risk were observed for recreational activity, lifetime or later life activity, vigorous activity, among postmenopausal women, women with normal BMI, non-white racial groups, those with hormone receptor negative tumours, women without a family history of breast cancer and parous women. The effect of physical activity on the risk of breast cancer is stronger in specific population subgroups and for certain parameters of activity that need to be further explored in future intervention trials.British journal of sports medicine 06/2008; 42(8):636-47. DOI:10.1136/bjsm.2006.029132 · 3.67 Impact Factor