IT IS worth re-emphasizing that the purpose of an exercise program for the minister is not that of being able to outrun or out-swim a competitor, nor to develop a set of biceps or leg muscles of which we can be proud. The psalmist tells us that the Lord "delighteth not in the strength of the horse: he taketh not pleasure in the legs of a man." 1
Rather, as we pointed out last month, the minister will seek to improve his physical condition so that his spiritual capacity will be increased and his ability for Christian service will be enlarged.
Your Exercise Program
When planning an exercise program, two preliminary considerations deserve mention. First, our level of physical fitness is similar to what has happened if we have become overweight. We did not get that way in a day and we cannot correct the situation in a day. This is no time for crash programs! A very long-range, enjoyable, new dimension of physical culture needs to be developed. It may take six months, a year, perhaps two years to reach our optimum level of physical fitness, and then a life time of maintaining its benefits.
Second, just as a two-week, annual vacation rest cannot replace the weekly Sabbath requirement, so one day off per week for recreation cannot compensate for the daily exercise requirement. Physical exercise sufficient to maintain physical fitness is to be a part of every day's program.
Some of our ministers feel that they must every day perform some labor that they can report to the conference, and as the result of trying to do this, their efforts are too often weak and inefficient. They should have periods of rest, of entire freedom from taxing labor. But these cannot take the place of daily physical exercise.
Brethren, when you take time to cultivate your garden, thus gaining the exercise you need to keep the system in good working order, you are just as much doing the work of God as in holding meetings. God is our Father, He loves us, and He does not require any of His servants to abuse their bodies.2
The absolute minimum of fitness exercise is three days per week. Less than this interrupts residual benefits and may produce more trauma than benefit.
Determining Your Pulse Rate
Body movement in exercise re quires energy. This energy comes basically from muscle fuel (glycogen) stored in the muscles. Glycogen is burned in the presence of oxygen, giving off energy for work, as well as heat and waste products. As the oxygen is utilized, carbon dioxide a by-product of the combustion is produced. The heart receives the signal to beat faster in order to circulate more blood so that more oxygen may be brought to the muscles, and in order to rid the blood of carbon dioxide through the lungs. Thus the heart really becomes an "oxygen pump" bringing fresh, oxygenated blood to the exercising muscles.
Because of this relationship (and because of convenience), the heart rate or pulse rate becomes the layman's primary monitoring system of how much stress is being placed on the body in exercise; i.e., how much energy is being used.
One must, therefore, be able to take his own pulse rate accurately. In a resting state or during very mild exercise, it may be convenient to take the pulse at the wrist. This is most easily done by resting one wrist, palm up, in the palm of the other hand. The fingers of the supporting hand curl naturally around the wrist to lie in the groove on the thumb side of the inner wrist. Gentle pressure will usually detect the pulse. If it is not found right away, move the fingers slightly back and forth toward the fingers and elbow, or across the wrist.
During exercise this method may be impractical. It may be more convenient to take the pulse rate at the carotid artery located on either side of the "Adam's apple" in the throat. This takes practice, and it may be necessary during the exercise routine to stop in order to take the pulse rate accurately. In the latter case it must be taken immediately upon stopping because the pulse rate begins to drop as soon as the exercise ceases. But if taken within a few seconds, this count is accurate enough. With practice, the carotid artery can be located quickly, even during exercise.
Count the number of beats within ten seconds and multiply by six, or the number of beats within fifteen seconds and multiply by four. When counting, always begin with zero: 0, 1, 2, 3, et cetera. A rather rough way is to count the number of beats within six seconds and simply add a zero to your count. Checking for accuracy can be done at leisure by comparing your multiplied count with a pulse rate taken for a whole minute--the surest method.
Are You Getting Enough Exercise?
Using any of the exercises recommended for obtaining physical fitness and using heart rate (HR) as the primary indicator of exercise load, how vigorously should you exercise and therefore what HR should be obtained during exercise?
Remember to get your physician's clearance before starting an exercise program. Unless there are abnormalities revealed in the evaluation testing or in your doc tor's physical examination that contraindicate its usage, the procedure described below is recommended.
There is a difference between your resting heart rate and your maximum heart rate. The work of Karvonen with treadmill running3 indicates that the heart rate must be increased to the value obtained by adding to your resting heart rate 60 to 85 percent of the difference between maximum and resting heart rates. Here is the way to calculate your exercise heart rate:
RHR = Resting Heart Rate, determined by taking an average of your pulse rate for three to five days just as you awaken in the morning, before getting out of bed.
MHR= Maximum Heart Rate. The MHR represents the maxi mum number of beats per minute the heart can safely perform normally. The MHR is age-adjusted. To determine, subtract your age from 220. The remainder is an estimate of your maximum heart rate.
EHR = Exercise Heart Rate. This is the heart rate which must be reached and maintained during an exercise routine in order to attain training effect. It is determined by the following formula,4 using the above-defined values:
[(MHR - RHR) X 60%] + RHR= EHR
For example:
Age 37
RHR= 50
MHR = 220- 37 = 183
[(183 - 50) x .60] + 50 = 130
This individual must reach and maintain a pulse rate of 130 during his exercise peak for the first three months of his exercise program. Since with regular exercise the Resting Heart Rate decreases, he needs to rework the formula with new figures involved, approximately every three months.
This gives a picture of what an exercise program is attempting to do. Just how long that exercise heart rate is to be maintained during one exercise session will be discussed in detail in the next article.
Physiological Basis for Your Exercise Program
One of the major benefits of training effect should be described here, however.
The heart muscle itself is nourished by small arteries called the coronary arteries. Should one of these become plugged (occluded), a person suffers a heart attack (coronary occlusion) that blocks the blood supply to a portion of the heart muscle (myocardium), which may produce a death (necrosis) of that area where oxygen from the blood did not reach. This necrotic area is called a myocardial infarct.
When the heart is in the act of pumping blood to the body, it is in a state of momentary contraction (systole), followed by a period of relaxation (diastole). Two thirds of the vital coronary blood flow that nourishes the heart itself occurs during diastole when the heart is at rest. The fewer times the heart beats within a minute, the more time is available for the heart to rest and for blood to flow through the coronaries. During exercise the heart rate is markedly increased (e.g., from 60 to 180 beats per minute), and the ability of the heart to squeeze itself with a powerful muscular contraction increases if the exercise is of sufficient intensity and duration to obtain training effect. With this increased contractility, (the ability of the heart to force more blood out of itself into the aorta with greater and more rapid force), more blood is supplied to the peripheral system with each beat. This lengthens the time before more blood is needed and the heart has longer to rest between contractions.
After several weeks or months of obtaining training effect, a per son's resting heart rate may decrease from as high as 70 beats per minute to 50 beats per minute, thus providing much more time throughout the day for the heart to be nourished with blood. So even if some irreversible narrowing has occurred in the coronary arteries from cholesterol deposits, more time for blood flow can provide the same, or at least adequate quantity of blood to sustain the heart.5
Of course, the fewer beats per minute that are required to maintain the body's blood supply the less wear there is on the heart and the longer life it should enjoy. If a person were to reduce his resting heart rate from 70 to 50 beats per minute, he would reduce the number of heartbeats from 100,800 to 72,000 per day; a saving of 28,800 per day. That's economy!
During exercise, while the heart is working vigorously, a greater demand for blood is made. Some research physicians believe this stimulates additional growth of blood vessels to nourish the heart, so that branches from coronary arteries on one side of the heart may overlap into an area on the other side of the heart.
If this is true, an occlusion occurring in a coronary artery in the heart of an individual who has not been in a good physical fitness regime might produce an infarct in the area supplied by that artery. But if exercise has stimulated the growth of additional blood vessels to nourish the heart, a blood sup ply would still be available to that region, preventing the infarct.
Thus, endurance exercise correctly performed can play an important part in heart-attack prevention.
(The conclusion of "Are You Fit for the Ministry?" will appear in The Ministry next month.)
FOOTNOTES
1. Ps. 147:10.
2. Ellen G. White, Counsels on Health, p. 564.
3. Herbert A. de Vries, Physiology of Exercise (William C. Brown Company Publishers, Dubuque, Iowa, 1971), p. 333.
4. Fred W. Kasch and John L. Boyer, Adult Fitness Principles and Practices (All American Productions and Publications, Greeley, Colorado, 1968), p. 29.
5. De Vries, op. cit., p. 67.
