In teen boys who are healthy, doing six weeks of regular cardio or short, intense sprints improves their fitness, but doesn't change their standard cholesterol numbers—meaning those blood tests might...

In teen boys, short bursts of intense exercise mainly lower free fatty acids in the blood, while steady, moderate exercise changes more types of fats—including sphingolipids and phospholipids—suggesting different kinds of workouts affect the body’s fat processing in different ways.

Doing short, intense sprints for six weeks might lower certain types of fats in the blood of healthy teenage boys, which could mean their bodies are using fat differently in a way that's good for their health.

For inactive middle-aged men with overweight or obesity, doing aerobic exercise or a mix of aerobic and strength training for 8 weeks lowers LDL cholesterol slightly more than doing strength training alone.

In young women with elevated body mass index, participating in supervised group aerobic exercise three times a week for twelve weeks is associated with measurable improvements in blood lipid levels, including increases in HDL cholesterol and decreases in LDL cholesterol, total cholesterol, and triglycerides.

For inactive middle-aged men with overweight or obesity, doing aerobic exercise for 8 weeks lowers total cholesterol levels more than doing resistance training.