Short-term trajectories of exercise-induced plasma lipid changes in overweight females, with a focus on HDL-cholesterol

Increased levels of plasma lipoproteins are among some of the modifiable risk factors for cardiovascular disease (CVD). Dietary changes and increased physical activity are the most powerful non-pharmacological interventions for achieving optimal plasma lipid levels. To investigate the effect of an intensive short-term lifestyle intervention on plasma lipid trajectories in overweight non-diabetic females. A total of 202 healthy overweight (body mass index (BMI) >27.5 kg/m2) females underwent an intensive short-term (ten-week) intervention (at least 4 units of one-hour exercise activity weekly at optimal energy intake) aimed at lowering body weight. Plasma lipid (total cholesterol (TC), low-density-lipoprotein cholesterol (LDL-C), high-density-lipoprotein cholesterol (HDL-C), and triglycerides (TG)) levels were examined at baseline and every 2 weeks over the course of the ten-week intervention. There was a significant decrease in BMI (Δ -4.7%, p < 0.001) and body weight (Δ -4.9%, p < 0.001) after the intervention. Positive changes (decreases) in TC (Δ -8%, p < 0.001), TG (Δ -9%, p < 0.001) and LDL-C (Δ -11%, p < 0.001) were observed immediately after 2 weeks, but levels did not decrease further thereafter. In contrast, HDL-C did not increase as expected: after 2 weeks of intervention, we observed a significant decrease of about 6% (p < 0.001) followed by a slow return to baseline values. But even after 10 weeks of intervention, HDL-C values had not reached the values detected at baseline. In overweight females, HDL-C decreased after short-term intensive lifestyle intervention. To confirm the protective effect of increased physical activity, plasma lipids need to be examined over a longer time period.