BACKGROUND: Studies addressing the effects of aerobic exercise and a prudent 
diet on lipid and lipoprotein concentrations in adults have reached conflicting 
conclusions. The purpose of this study was to determine the effects of aerobic 
exercise combined with a prudent diet on lipid and lipoprotein concentrations in 
adults.
METHODS: Studies were located by searching nine electronic databases, 
cross-referencing, and expert review. Two independent reviewers selected studies 
that met the following criteria: (1) randomized controlled trials, (2) aerobic 
exercise combined with diet recommendations (saturated/trans fat intake less 
than 10% of total calories and cholesterol less than 300 mg/day and/or fiber 
intake ≥ 25 g/day in women and ≥ 35 grams per day in men), (3) intervention ≥ 4 
weeks, (4) humans ≥ 18 years of age, (5) published studies, including 
dissertations and Master's theses, (6) studies published in any language, (7) 
studies published between January 1, 1955 and May 1, 2009, (8) assessment of one 
or more of the following lipid and lipoprotein concentrations: total cholesterol 
(TC), high-density lipoprotein cholesterol (HDL-C), ratio of TC to HDL-C, 
non-HDL-C, low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG). 
Two reviewers independently extracted all data. Random-effects models that 
account for heterogeneity and 95% confidence intervals were used to pool 
findings.
RESULTS: Of the 1,401 citations reviewed, six studies representing 16 groups (8 
intervention, 8 control) and up to 559 men and women (282 intervention, 277 
control) met the criteria for analysis. Statistically significant intervention 
minus control reductions were found for TC (-15.5 mg/dl, 95% CI, -20.3 to 
-10.7), TC:HDL-C (-0.4 mg/dl, 95% CI, -0.7 to -0.2), LDL-C (-9.2 mg/dl, 95% CI, 
-12.7 to -5.8) and TG (-10.6 mg/dl, 95% CI, -17.2 to -4.0) but not HDL-C (-0.5 
mg/dl, 95% CI, -4.0 to 3.1). Changes were equivalent to reductions of 7.5%, 
6.6%, 7.2% and 18.2% respectively, for TC, TC:HDL-C, LDL-C and TG. Because of 
missing variance statistics, non-HDL-C was excluded.
CONCLUSIONS: Aerobic exercise combined with a prudent diet is highly efficacious 
for improving TC, TC:HDL-C, LDL-C and TG, but not HDL-C concentrations, in 
adults. However, additional studies are needed, including effectiveness studies 
using intention-to-treat analysis.