A poor association was found between self-reported physical activity and estimated maximal oxygen uptake of sedentary multiethnic women Maaike G.J. Gademan a, * , Karen Hosper a , Marije Deutekom a , Raoul H.H. Engelbert b,c , Jonathan Myers d , Karien Stronks a a Department of Public Health, Academic Medical Centre, Meibergdreef 9, Postbus 22660, 1100 DD Amsterdam, The Netherlands b Education of Physiotherapy, Amsterdam University of Apllied Sciences,Tafelbergweg 52, 1000 CN Amsterdam, The Netherlands c Department of Rehabilitation, Academic Medical Center, Meibergdreef 9, Postbus 22660, 1100 DD, Amsterdam, The Netherlands d Department of Cardiology, Palo Alto Veterans Affairs Medical Center and Stanford University, Palo Alto, CA 94304, USA Accepted 11 November 2013 Abstract Objectives: In health evaluations, physical activity (PA) and cardiorespiratory fitness (maximal oxygen uptake [VO 2 max]) are impor- tant variables. It is not always possible to assess both of them. If the association between self-reported PA and VO 2 max was strong, it would be possible to use the information on PA to make assumptions about VO 2 max and vice versa. However, little is known about this relation, in particular among women at high risk for cardiovascular disease. Our aim was to study the association between self-reported PA (Short QUestionnaire to ASses Health enhancing PA) and fitness (determined using the Siconolfi step test) among sedentary women in a multi- ethnic population. Study Design and Setting: Participants were sampled from an exercise program for sedentary women (The Netherlands, 2008e09). Linear regression was performed with VO 2 max (dependent variable) and self-reported PA (independent variable); covariates were age and body mass index. Results: One hundred ninety-seven women from different ethnic backgrounds were included. No significant association was found be- tween VO 2 max and PA (R 2 5 0.60). Conclusion: A poor association was found between self-reported PA and estimated VO 2 max. Hence, PA and VO 2 max represent two different aspects of health in sedentary women and cannot be used interchangeably. This should be taken into account when evaluating health promotion interventions or when making health risks statements in sedentary women in a multiethnic population. Ó 2014 Elsevier Inc. All rights reserved. Keywords: Exercise test; Ethnic groups; Self-report; Physical activity; Women; Sedentary 1. Introduction In Western society, people are increasingly physically inactive (World Health Organization, 2010). As a conse- quence, health problems related to physically inactivity are emerging. For instance, according to the World Health Organization, in 2015, 23 billion people around the world will have a body mass index (BMI) in the overweight or obese range, markedly increasing the risk for cardiovascu- lar disease. Physical inactivity has become one of the biggest public health problems of the 21st century [1], with at least 60% of the global population failing to achieve the minimum recommendation of 30 minutes moderate inten- sity physical activity (PA) daily (World Health Organiza- tion, 2010). Conversely, both greater PA and higher cardiorespiratory fitness have beneficial effects on health and longevity. Therefore, health interventions promoting PA and cardiore- spiratory fitness are evolving. Strong evidence for the health benefits of PA and physical fitness is present [2,3]. PA protects against many chronic health conditions by improving glucose uptake and insulin sensitivity, improving blood lipid profiles, lowering blood pressure, improving the health of blood vessels, and reducing obesity [3]. PA has been defined as ‘‘any bodily movement produced by contraction of skeletal muscles and resulting in energy (ENE) expenditure above the basal level’’ [4]. PA is often assessed with self-report questionnaires [5] as these tools Conflict of interest: None. * Corresponding author. Department of Public Health, Academic Med- ical Centre, Meibergdreef 9, Postbus 22660, 1100 DD, Amsterdam, The Netherlands. Tel.: þ31-20-566-7633; fax: þ31-020-697-2316. E-mail address: m.g.gademan@amc.uva.nl (M.G.J. Gademan). 0895-4356/$ - see front matter Ó 2014 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jclinepi.2013.11.004 Journal of Clinical Epidemiology 67 (2014) 462e467