081119 Aerobic exercise and high blood pressure.
High blood pressure has been called “the silent killer”, and for good reason. People with high blood pressure normally do not even realize they have it. There are no outward signs until a stroke, coronary artery disease, or kidney failure suddenly shows up in a life-threatening event.
Blood pressure is the resistance the heart faces as it attempts to pump blood through the body. The top number (systolic) is the amount of resistance the heart has to overcome in order to push the blood throughout the body during a contraction. The bottom number (diastolic) is resistance in the system while the heart is at rest. Any number combination greater than 140/90 is considered high blood pressure. This condition needs a doctor’s attention. Many people have high blood pressure and don’t even know it. Do you know what yours is? If not get it checked and find out, it just may save your life.
Many studies over the past ten years have found that a properly designed exercise program can, in some cases, lower the blood pressure numbers as much as 10-20 mm hg. (From Exercise Physiology page 805-810)
Aerobics conducted at a moderate rate of 50-70% of your target heart rate for 30-45 minutes daily on a treadmill, bicycle, stair stepper or any other type of sustained activity seems to be the ticket to better heart health. The 30-45 minutes of daily activity does not have to be all at once but can be split into several sessions during the day. Even ten-minute sessions, several times a day, may produce noticeable changes in your numbers. Of course this is in conjunction with a modification of your diet to a more healthy life style of eating patterns.
An accurate way to figure your target heart rate is to use the Karvonen method. (The Percentage of Maximum Heart Rate, calculation can be off by as much as 10 beats per minute, but it is normally the one used on the large chart found on many gym walls).
To calculate your target heart rate, follow this formula: (from the second edition of Essentials of Strength Training and Conditioning by T.R.Baechle and R.W Earle page 500):
- Age-predicted maximum heart rate (APMHR)=220-age.
- Heart rate reserve (HRR)=APMHR-resting heart rate (RHR). Take this before you arise in the morning.
- Target heart rate (THR)= (HRR x Exercise intensity) + RHR
Do this calculation twice to determine the target heart rate range (THRR).
NOTE: Check with your doctor before beginning any new exercise program. Do not stop taking blood pressure medication without consulting with your doctor.
*The National Strength and Conditioning Association (NSCA) has a complete list of certified trainers that are capable of assisting you in your quest to better health. The NSCA can be reached at 1.800.815.6826 or at www.nsca-lift.org.