 Exercising in Heat Can Be Hard on Heart Source: American Heart Association, Posted: 07/24/2008 by VP Staff While temperatures these past few days of July have been comfortable, the dog days of summer are just around the corner and that means you need to guard against dehydration, heat exhaustion and heat stroke. Heat and humidity interfere with the body's natural cooling mechanism, ane these risks increase when the the humidity is above 70 percent and the temeperature is above 70 degrees. The problem is made worse because the heart is trying to deliver blood and oxygen to your working muscles while your body is trying to cool off by sweating. If you sweat too much, you lose fluid, and this decreases your total blood volume. That means your heart has to pump even harder to get the smaller volume of blood to your working muscles, skin and the other body parts. If you lose too much fluid, your body temperature rises and your nervous system malfunctions. Extreme fluid loss can lead to brain and heart damage. If you plan to exercise outside in hot and humid weather, wear light, comfortable clothing and exercise in the early morning or late evening if possible. Know the symptoms of heat exhaustion and heat stroke. If any symptoms appear, stop exercising and cool off immediately by dousing yourself with cold water. Heat exhaustion can progress quickly to heat stroke, and that can be fatal. Don't hesitate to seek medical attention if you exhibit the following symptoms: Heavy sweating; cold, clammy skin;,dizziness or fainting; a weak and rapid pulse; muscle cramps; fast, shallow breathing; nausea, vomiting or both. Heat stroke symptoms include: Warm, dry skin with no sweating; strong and rapid pulse; confusion and/or unconsciousness; high fever; throbbing headaches; nausea, vomiting or both. Obesity is Heart Unfriendly Source: Journal of the American College of Cardiology, Posted: 05/15/2008 by VP Staff A US study of 7,000 people of multiple ethnicities provided compelling evidence of what has long been suspected: obesity is hard on the heart. The latest findings from the Multiethnic Study of Atherosclerosis are believed to provide the first large-scale evidence of such a link. "The biological effects of obesity on the heart are profound," said senior study investigator Dr. Joao Limo, a professor of medicine and radiology at the John Hopkins University School of Medicine and its Heart Institute. "Even if obese people feel otherwise healthy, there are mesurable and chemical signs of damage to the heart." In the study of people ages 45 to 84, 44 percent who developed congestive heart failure were physically obese. "Now there is even more reason for (obese people) to lose weight, increase their physical activity and improve their eating habits," Lima said.
Fat and Fit? Weight Matters Source: Archives of Internal Medicine, Posted: 05/06/2008 by VP Staff Forget about being fat and fit, according to a recent study appearing in Archives of Internal Medicine. The study says that while being active can lower your heart risk, it won't eliminate it. "It doesn't take away the risk entirely. Weight matters," said Dr. Martha Gulati, a heart specialist at Northwestern Memorial Hospital. Previous research has been inconclusive on whether exercise or weight has greater influence on heart disease risks. The new study, involving nearly 39,000 women age 54 on average and tracked over 11 years, helps distinguish between the effects of physical activity vs body mass and the probability of developing heart disease. The study found that the risk for developing heart disease was 54 percent higher in overweight active women and 87 percent higher in obese active women. By contrast, it was 88 percent higher in overweight inactive women; and 2 1/2 times greater in obese inactive women. Women were considered active if they got at least 30 minutes of moderate activity most days, including brisk walking or jogging.
Early Cardiac Signs in Teens Source: Circulation, Posted: 05/01/2008 by VP Staff A new study reveals that heart-disease risk in men develops during adolescence. The journal Circulation reports that signs of cardiac arrest like rising blood pressure and fat levels occur in teen boys, even as their levels of body fat and good cholesterol drop, according to the May 6th issue. By age 19 the study also found boys were more insulin resistant, putting them at a higher rates for developing diabetes. At the same time, researchers noted the opposite occuring in teenage girls, whose body fat levels rise during puberty. Systolic blood pressure increased in both teen boys and girls, but it increased significantly more in boys, the study reports.
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