Women's EXPLORE study

Background and context

International exercise guidelines have been designed to prevent weight gain, and subsequently improve health, in adults. However, body mass is a proxy for assessing obesity, and fat distribution also plays an important role in metabolic and cardiovascular health. Given the importance of adiposity in obesity-related disease risk, it is imperative that prescribed exercise guidelines be relevant to preventing gains in both weight and fat mass.

This study investigated the impact of achieving recommended levels of physical activity on adiposity in normal-weight women with varying levels of percentage body fat.

Results

Achieving current physical activity recommendations (150 min/week or more of moderate-to-vigorous physical activity) was associated with significantly lower percentage body fat (27.4% ± 5.7 vs 30.3% ± 4.08; p=0.038). When physical activity was stratified, those achieving 300 min/week or more of moderate physical activity showed a trend towards lower percentage body fat (p=0.076), while achieving 150 min/week or more of vigorous physical activity resulted in significantly lower percentage body fat (24.5% ± 4.3 vs 28.3% ± 5.5; p=0.022).

Achieving current physical activity recommendations was associated with a moderate, but clinically relevant decrease in percentage body fat. The findings suggest this association is strongest for vigorous activity.

Conclusions

The findings suggest that while moderate-to-vigorous physical activity will help achieve lower levels of adiposity, an emphasis on vigorous physical activity may have the greatest impact on adiposity when prescribing exercise in normal-weight women.