Figure 12-2 
Figure 12-3 
Figure 12-4 
Figure 12-5 
Figure 12-6 
Figure 12-7 
Figure 12-8 
We know by now that the food we eat provides fuel for energy and building blocks for body growth and maintenance. A typical meal contains a number of nutrients: fats, proteins, carbohydrates (collectively known as "macronutrients"), water, vitamins, minerals (collectively known as "micronutrients"), and fiber (technically not a nutrient at all, but considered an essential ingredient in a healthy diet). This month's Newsletter deals mainly with carbohydrates, fats, and pro-teins; but with at least a cursory mention of the others.
Their function in the human body is to be helpers (catalysts). They do not form energy; rather, they assist enzymes (see Note 1) with energy production, and cell multiplication. They are needed in only very small quantities, but in insufficient quantities can have serious consequences - blindness, mental illness, growth retardation, and other equally unpleasant phenomena.
_______________________________
Note 1 - Enzymes are proteins that assist chemical reactions without being changed in the process.
_______________________________
Fiber is just a non-digestible (by human enzymes) form of complex carbohydrates (e.g., cellulose). This component of plants is considered to help prevent several diseases, primarily of the GI tract.
Minerals are inorganic elements that can ionize (become charged particles) when in solution, and can then form compounds (e.g., sodium chloride). Some major minerals are calcium, phosphorus, sodium, chloride, potassium, magnesium, and sulfur. Others, called trace elements (e.g., chromium and selenium) are needed only in minute quantities. While essential to human life, minerals, like some vitamins; if taken in excess, may be fatal.
Fluids, the main constituent of which is water, are where all chemical reactions in the body take place. Fluids ferry nutrients and waste products around in the body, are part of all chemical reactions, fill cells and spaces between them, act as a joint lubricant, play a major role in temperature regulation, and more. The water component of body fluids makes up about 55-60% of an adult's body weight; even more for a child's. It is easy to understand the admonition to drink lots of water. Try not to become dehydrated, but if it happens, rehydrate as soon as possible.
Now on to the macronutrients - fats, carbohydrates, and proteins.
Fats to the scientific world are called lipids; and include mainly triglycerides, phospholipids, and sterols (the most commonly known of which is cholesterol). Triglycerides are contained in food, and are the most space- efficient form of energy in the body. It provides nine calories per gram (as opposed to either proteins or carbohydrates, which provide only four calories per gram. It also requires far less energy to be stored in the body than carbohydrates. Note that protein is not stored in the same way as fats or carbohydrates. It is essentially used, or eliminated. A triglyceride molecule contains a glycerol component to which three fatty acids (FAs) are attached. These FAs can become fuel for our muscles.
Phospholipids are contained in food, or synthesized in the liver and small intestine. They contain a glycerol component, two FAs, and a third compound - usually phosphorus and nitrogen. Phospholipids often become part of cell membranes.
Cholesterol is found in foods and is synthesized in the liver. It is necessary stuff - involved in synthesis of hormones like testosterone and estrogen; and is part of every cell in the body. The body manufactures what it needs. We would be perfectly healthy if we ate nothing containing cholesterol. Because we do, many of us end up with clogged arteries. Another case of getting too much of a good thing.
Carbohydrates consist of simple sugars like glucose, galactose, and fructose, which are converted in the liver to fuel forms. Other sugars form part of DNA and RNA. The simple sugars are found free in some foods, but also result from digestion of complex carbohydrates - starch and glycogen. Carbohydrate storage as a potential energy source is less efficient than that for fat; not only because of the calorie density issue, but also because they are stored with significant amounts of water, which further dilutes energy potential.
Proteins are used in the body to make connective tissue (e.g., ligaments and tendons), hormones, and muscles. They are the "construction" materials of our bodies. Proteins are made up of long chains of amino acids. There are 22 known amino acids in the human body; nine are called "essential" by virtue of their not being produced in the body. They must be included in one's diet. The other 13 amino acids are synthesized in the liver and kidneys from foods ingested, but only if sufficient amino acids are available at the site of synthesis.
A balanced diet is necessary to provide the nutrients needed by our bodies:
A neural mechanism works to activate enzyme secretions and gut motility. The stretch of the digestive tube cues the system that food is coming.
The food we eat obviously isn't pure protein, or carbs, or fats - it is all mixed together. But in the stomach, through a little magic, the nutrients are sent off to the proper "bins" for processing. It isn't fully understood how this is done, but it is. The order of release is: carbohydrates, then proteins, and, finally, fats.
Simple sugars require no digestion beyond the mouth. They arrive at the small intestine within minutes after being ingested. They are rapidly absorbed into the blood and carried to the liver where they are converted into glucose. It may remain in the liver, or re-enter blood circulation, and get shipped to various cells in the body. The body's response to simple sugars is to release insulin from the pancreas into the blood where it transports glucose into cells. In essence, glucose is being stored - not so good if you need it immediately for energy.
Complex carbohydrates are broken down into simple sugars which go to the liver, and then are treated like any other simple sugars. But their progress is somewhat delayed by the diversion to the liver, rather than going immediately into the blood. Thus, the insulin response is more gradual. At any rate, whatever the source, glucose is:
The stomach and pancreas work on proteins by extracting the individual amino acids, called "free amino acids," and sending them to the liver (see Note 2). Amino acids from food eaten are joined by amino acids derived from the digestive enzymes themselves. [Remember that enzymes are proteins.] Therefore, you end up with a broader mix of amino acids than what came from the food you ate. This process provides the explanation for why we don't have to eat "complete" protein (or all of the essential amino acids) at each meal as was once thought. All essential amino acids do, however, need to be ingested each day. That is because there is no storage of amino acids for a future use. [The only "stored" amino acids are contained in muscle tissue, which has to be cannibalized to be retrieved. This has been discussed in previous Newsletters, so I won't go into details again.] Amino acids transported to the liver may be:
This discussion is limited mainly to triglycerides, since that is the primary storage and fuel forms of fat. Because fat isn't water soluble, the first step is to provide bile salts from the liver. It breaks fat into smaller particles. Fat digesting enzymes can now break apart the glycerol and FA components of triglycerides.
The FAs may be either short-chain or long-chain. The short-chain variety goes to the liver, where it can be used as fuel, or converted (along with any other remnants, as from amino acids) back into triglycerides. These liver-generated triglycerides are then coated with protein and phospholipids to make them water soluble. What is now called a "lipoprotein" is the vehicle by which fat is transported to cells for fuel. Fat is transported through the blood by being disguised as protein. The fate of the long-chain FAs is a bit different.
They are converted back into triglycerides, and along with cholesterol, are coated in a protein and phospholipid "jacket." These, now water- soluble "bits" called chylomicrons, move into the lymphatic system. They then bypass the liver, and go directly to cells. Ultimately, lipoproteins from the liver, along with the chylomicrons, move through body cells and release triglycerides and cholesterol. The triglycerides are again broken down to FAs, which are used as fuel or reconverted to triglycerides for energy storage. After all of this technobabble, it is fair to say that fat either gets used immediately for fuel, or gets stored for later. For seriously obese people, of course, "later" never comes.
It used to be thought - actually it still is by many - that athletes need more protein than non-athletes. And it looks like they are correct. But, not a huge amount more, and, in fact, the average American diet includes more than an adequate amount. At any rate, if one's diet provides enough energy to cover expenditure, lean tissue (muscle) can be produced even on lower than recommended levels of protein - .8 grams per kilogram of body weight is the standard recommendation; as much as 1.2 grams for athletes; and, according to a U.C.-Berkeley study, .57 g/kg body weight were sufficient under the "adequate-energy-in-thediet" condition.
A diet that provides 75% of calories from carbohydrates, 15% from proteins, and 10% from fat is considered to be a reasonable nutrition plan to follow. Some recommend a 60% 20% 20% plan, with no more than 10% saturated fat.
and
Happy New Year
Now let's get started on sports strength and flexibility programs. As I started to assemble a list, it became immediately obvious that exercises for specific sports vary only slightly from a normal fitness program. Therefore, only new or modified exercises are presented in detail, the others reference earlier Newsletter issues which described them.. These exercises can sup-plement or replace exercises in your normal program. You do have one, don't you?
Here are some stretches which are well-suited to golf. When you perform these, or any, stretches remember to breathe, and to stretch to the point of tightness, but never to the point of pain. And be aware that the stretches as described are a goal, don't force a stretch beyond your normal ROM. Also, ideally, stretching should be preceded by a general warm-up. Try these:
Figure 12-2
Figure 12-3
Figure 12-4
Figure 12-5
Figure 12-6
Figure 12-7
Figure 12-8
(Q) It seems that there have recently been some
outbreaks of deadly diseases, mostly in Africa (tropical areas), that
have panicked people. Why are they suddenly appearing, as if from
outer space?
J.M., Sacramento, CA
A I assume that you are referring to ebola (one of the diseases categorized as hemorragic fever - often fatal from either massive hemorrage, or multiple organ failures). According to an article in the October '95 issue of Scientific American, hemorragic fever comes from a virus, which has actually been around for a long time. Because these viruses survive in places like rain forests or savannas, current outbreaks have been caused by environmental changes, like excessive rain; or man-made changes, like cutting down forests. The viruses may be spread by insects or animals (e.g., mosquitoes, monkeys, or mice). An environmental disruption causes the viruscarriers to move into new areas. Consequently, flare-ups of hemor ragic fever occur in new areas. These virulent fevers die out quickly because they kill so fast. Circulation requires human carriers. That's why these viruses usually spread in primitive areas where there are poor or no medical facilities. Air transportation could introduce these old killers into heavily populated areas. A frightening thought.
Due to production costs, beginning with the January 1996 issue of the MAF FITNESS NEWSLETTER, it has become necessary to charge new subscribers $12.00 per year (payable to M. A. Fenner). Current subscribers may feel free to make a donation, or not. Thanks for understanding the realities of today's business environment.
_______________________________
For questions, call (408) 739-0501, or write to:
MAF, 964 Ponderosa Ave., Suite 25, Sunnyvale, CA 94086-8931.
Email to Mike_Fenner@netcom.com