Facts About Cholesterol
Cholesterol is a necessary part of a healthy body as it helps produce cell membranes and some hormones, and assists in many other bodily functions. However, too much cholesterol in the bloodstream can lead to coronary heart disease and stroke.
Our bodies strive to control cholesterol levels automatically. However, when large amounts of cholesterol-heavy foods are eaten--especially those high in saturated and trans fats--the body becomes too overwhelmed with cholesterol to regulate levels properly.
Cholesterol is composed to two different types of lipoproteins.
HDLs (high-density lipoproteins) are considered the good type of cholesterol. These lipoproteins help clear excess fat and cholesterol from the bloodstream.
LDLs (low-density lipoproteins) are the bad type of cholesterol. These lipoproteins contribute to plaque buildup on artery walls increasing the risk for heart disease.
Effects of Exercise
The biggest effect exercise has on cholesterol is its ability to boost HDLs and lower triglycerides (the chemical form of fat in the body). Proper exercise stimulates metabolic enzyme systems in the muscles and liver, which helps convert some of your total cholesterol into HDLs. Exercise lowers triglycerides in large part by promoting weight loss. This reduction of triglycerides then helps break down the growth of fatty deposits on artery walls.
Additionally, exercise improves circulation and enhances the cardio respiratory system (heart and lungs), allowing it to work at peak efficiency. This in turn clears blood vessels and strengthens the heart.
To improve cholesterol levels--increase HDLs and decrease LDLs--exercise must be consistent. To boost HDLs and lower triglycerides, exercise must expend enough energy to burn about 1,200 calories per week, with the typical recommendation being 2,500 to 3,000 calories/week.
To some, this may sound high, but over the course of a week it is possible for anyone. For example, walking three miles over an hour--or 20 minutes a mile--burns an average of 300 calories. This means walking for one hour/day four days every week could improve cholesterol 10 to 20 percent in 12 to 16 weeks.
It's still in question whether exercise intensity is a factor in altering cholesterol levels. However, it's typically assumed that exercise must be at least moderate to see significant changes.
It's important to note that exercise alone will not solve all cholesterol problems. The main culprit behind poor cholesterol is a diet high in saturated animal fats (high-fat meats and dairy) and trans fats (hydrogenated oils). Limiting these fatty foods and bulking up on fruits, vegetables, grains and unsaturated fats can decrease LDLs as well as increase HDLs. Pair this with regular exercise and your cholesterol woes could disappear.