Physical activity, total and regional obesity: Dose-response considerations

School of Physical and Health Education, Queen's University, Ontario, Canada.
Medicine &amp Science in Sports &amp Exercise (Impact Factor: 3.98). 06/2001; 33(6 Suppl):S521-7; discussion S528-9. DOI: 10.1097/00005768-200106001-00023
Source: PubMed

ABSTRACT This review was undertaken to determine whether exercise-induced weight loss was associated with corresponding reductions in total, abdominal, and visceral fat in a dose-response manner.
A literature search (MEDLINE, 1966--2000) was performed using appropriate keywords to identify studies that consider the influence of exercise-induced weight loss on total and/or abdominal fat. The reference lists of those studies identified were cross-referenced for additional studies.
Total fat. Review of available evidence suggested that studies evaluating the utility of physical activity as a means of obesity reduction could be subdivided into two categories based on study duration. Short-term studies (< or = 16 wk, N = 20) were characterized by exercise programs that increased energy expenditure by values double (2200 vs 1100 kcal.wk-1) that of long-term studies (> or = 26 wk, N = 11). Accordingly, short-term studies report reductions in body weight (-0.18 vs -0.06 kg x wk(-1)) and total fat (-0.21 vs -0.06 kg x wk(-1)) that are threefold higher than those reported in long-term studies. Moreover, with respect to dose-response issues, the evidence from short-term studies suggest that exercise-induced weight loss is positively related to reductions in total fat in a dose-response manner. No such relationship was observed when the results from long-term studies were examined. Abdominal fat. Limited evidence suggests that exercise-induced weight loss is associated with reductions in abdominal obesity as measured by waist circumference or imaging methods; however, at present there is insufficient evidence to determine a dose-response relationship between physical activity, and abdominal or visceral fat.
In response to well-controlled, short-term trials, increasing physical activity expressed as energy expended per week is positively related to reductions in total adiposity in a dose-response manner. Although physical activity is associated with reduction in abdominal and visceral fat, there is insufficient evidence to determine a dose-response relationship.

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    • "Reductions in vocational physical activity and the availability and consumption of energy-dense foods are often cited as primary culprits of the rising incidence of obesity observed throughout the world [1] [2] [3] [4] [5] [6]. The increased incidence of obesity has presented both health-related and economic challenges which exceed $110 billion dollars per year in the US alone [7], a level which surpasses any other country in the world. "
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    Journal of nutrition and metabolism 06/2014; 2014(5). DOI:10.1155/2014/902065
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    • "This is most evident when the exercise dose is substantial (≥60 min/day) [3]. In studies of regimens lasting 26 weeks or more (n = 12), researchers determined that there was no dose–response relationship between prescribed energy expenditure and weight loss and that actual weight loss was only 30% of what was expected [3]. "
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    Trials 06/2014; 15(1):212. DOI:10.1186/1745-6215-15-212 · 1.73 Impact Factor
    • "For example, a combination of increased high volume of EE and dietary counseling has been shown to achieve target weight loss (Ross et al., 2000). However, several studies without dietary intervention, involving moderateintensity continuous training reported a lower than predicted weight loss (Donnelly et al., 2000; Ross & Janssen, 2001). High-intensity interval training has also resulted in variable changes in body weight (Trapp et al., 2008). "
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