How exercise affects blood fat levels
Gabe Mirkin, M.D.
Regular exercise may help to prevent heart attacks by lowering insulin. When you
eat, blood sugar levels rise and the higher they rise, the more insulin is
released by your pancreas. You need insulin to keep blood sugar levels from
rising too high, but it constricts arteries to cause heart attacks. When you
exercise, you contract your muscles. Contracting muscles draw sugar from the
bloodstream without requiring insulin. This keeps blood sugar levels from rising
too high and prevents a high rise in blood insulin levels.
High blood levels of insulin lower the good HDL cholesterol and raise
triglycerides, but do not affect the bad LDL cholesterol levels. Exercise lowers
insulin levels and raises HDL, but does not lower LDL cholesterol levels.
Even if you are not diabetic or otherwise concerned with high blood sugar
levels, you can benefit from a regular exercise program that lowers blood
insulin levels. A good program might include alternating a primarily upper body
exercise such as rowing with a primarily lower body exercise such as jogging.
Alternating muscle groups allows your muscles to feel fresh each day and helps
to prevent injuries.
Diet to lower cholesterol
AE Hardman. Role of exercise and weight loss in maximizing LDL cholesterol
reduction. European Heart Journal Supplements, 1999, Vol 1, Iss S, pp