Comparison of aerobic exercise, diet or both on lipids and lipoproteins in adults: a meta-analysis of randomized controlled trials.

OBJECTIVE

Given that previous studies have reached conflicting conclusions regarding the effects of diet (D), aerobic exercise (E) or both (DE) on blood lipid and lipoprotein concentrations in adults, the meta-analytic approach was used to address this issue.

DATA SOURCES

Nine electronic databases, cross-referencing, and expert review.

STUDY SELECTION

Randomized controlled trials ≥ 4 weeks that included a D, E, DE and control (C) group in adults ≥ 18 years of age and in which data for one or more of the following were available: total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG).

DATA EXTRACTION

Dual data extraction by the first two authors.

STATISTICAL ANALYSIS

Random-effects models as well as mixed-effects models for between-group differences.

RESULTS

Seven-hundred and eighty-eight men and women from 6 studies were included. Non-overlapping 95% confidence intervals were observed for D and DE with respect to lowering TC, LDL-C and TG while reductions in E were limited to TG. No significant changes in HDL-C were observed. When compared to E, reductions in TC and LDL-C were greater for D and DE (p < 0.05 for all).

CONCLUSIONS

Diet, especially DE, are superior to E for improving selected lipids and lipoproteins in adults.