American College of Sports Medicine Position Stand. Appropriate physical activity intervention strategies for weight loss and prevention of weight regain for adults.
Level 5 - mechanism / opinion, no new human data
Professional society position stand and narrative practice guideline.
PubMed 19127177 · doi:10.1249/MSS.0b013e3181949333
What was done
The American College of Sports Medicine (ACSM) reexamined scientific evidence from 1999 to evaluate the dose-response relationship between physical activity volume and weight gain prevention, weight loss, and weight regain prevention in adults.
What was found
The review reported the following activity thresholds: - Moderate-intensity physical activity (PA) between 150 and 250 min/week prevents weight gain and produces modest weight loss. - PA >250 min/week is associated with clinically significant weight loss and improved post-weight-loss maintenance. - PA between 150 and 250 min/week improves weight loss in the presence of moderate dietary restriction, but not severe dietary restriction. - Resistance training does not enhance total weight loss, but increases fat-free mass, increases loss of fat mass, and reduces health risks. - Endurance or resistance training without weight loss improves health risk markers. - Exact quantitative metrics (such as mean kilograms lost or effect sizes) are not reported in the abstract.
Why it matters
This guideline establishes that standard exercise recommendations (150 min/week) suffice for weight stability, but higher volumes (>250 min/week) are necessary for clinically significant weight reduction and long-term weight maintenance.
Limits
The abstract notes that no well-designed randomized controlled trials exist to determine the effectiveness of physical activity for preventing weight regain after weight loss. There is also inadequate evidence to determine whether physical activity prevents health risk changes during active weight gain. Total studies reviewed and precise quantitative effect sizes were not provided in the abstract.
Cited by
- supports Thirty minutes of daily exercise improves cardiovascular function and lowers risk for heart disease, diabetes, and certain cancers, but is insufficient to manage body weight.