hypertension (high blood pressure) is called the silent killer because the first symptoms are sometimes heart attack or stroke. Blood vessels are pliable tissues that stretch and rebound as the heart contracts and relaxes. Blood pressure increases if the blood vessels are stiff
and impliable. Heavy weight training creates incredible pressures in the arteries that have been measured as high as 400 millimeters of mercury (normal mean blood pressure is 100mm Hg.).
Chronic, heavy weight training can stiffen the arteries, particularly the carotid arteries leading to the brain. Japanese researchers found that adding aerobics to the exercise program prevented carotid artery stiffening in young men who weight trained. Bodybuilders should include aerobics in their training program to help cut fat and maintain healthy arteries.
Many endurance athletes avoid strength training like the plague. Even when they lift weights, they do low-resistance and high-repetition programs. This is curious because running speed depends on the force exerted against the ground. Stronger people can push harder against the ground than weaker people can. Strength guru Dr. Mike Stone and his colleagues from the U.S. Olympic Training Center discussed the importance of strength training for endurance athletes. Maximum strength is strongly related to endurance, particularly in high-intensity endurance events.
Increasing strength improves endurance capacity in all endurance sports. Specificity is critical: the training program should build strength and power that meets the requirements of the activity. Increases in strength should be continuously integrated into the skill. All serious endurance athletes should include weight training and plyometric exercises in their programs.