You've lost count of the number of phone calls you fielded all afternoon-the last was from your son, who missed the late bus home from school-and colleagues needing your decision are lined up outside your office. Your husband has invited clients home for dinner. You wilt like a new hairdo on a damp August day and pray for a miracle to jump-start your engine.

Your pep quotient depends on three essential ingredients: nutrients you consume through your diet and supplements, how much you exercise and your sleep schedule.(Of course, if you're troubled by any kind of disabling, ceaseless fatigue accompanied by mental fuzziness, joint pain, sore throat, swollen glands, headaches and other chronic distress, consult your health practitioner.)

Vitamins and Energy
Certain nutrients are called vitamins because scientists consider them to be crucial for vitality. They generally function as coenzymes, partnering with the enzymes that are catalysts for the chemical reactions constantly taking place in our bodies.
Our need to replenish our store of vitamins, which may merge with cell, muscle, enzyme, hormone, blood and bone structure once they have been absorbed, depends on their rate of utilization, according to The Real Vitamin & Mineral Book (Avery) by Shari Lieberman, PhD, and Nancy Bruning.

While a low-fat diet rich in raw fruits and vegetables helps supply important nutrients, a B complex supplement and a balanced multivitamin can guarantee daily vitamin levels.

Be Energetic with B Vitamins
Vitamins, especially the B vitamins, play extremely important roles in producing cellular energy. The chart on page 39 lists the key vitamins and describes their effects as well as the consequences of not getting enough of them. Their benefit is felt most profoundly in the energy producing process known as the Krebs cycle (which we'll explain in a moment).

Vitamins B2 and B3, for example, supply the major building blocks for substances that are called flavin adenine dinucleotide (FAD and FADH) and nicotinamide adenine dinucleotide (NAD and NADH), which are critical elements of energy production in the Krebs cycle as well as a process called oxidative phosphorylation.

Hundreds of Reactions
Even though you may never have heard of NAD and NADH, these molecules are found in very many places throughout your body; they play a role in hundreds of biochemical reactions in all kinds of cells. B vitamins also combine with other materials to build coenzymes, chemicals which help form other chemicals necessary for cellular energy. B vitamins are crucial: miss out on one or more and you may break these metabolic chains necessary for peak energy.

Energy to Spend
The main energy currency of every cell single cell is ATP: a chemical called adenosine triphosphate. This material is used by cells for every imaginable task including reproduction, growth, movement and metabolism. Specialized metabolic cycles within the cell are designed to generate ATP.

Consequently, the more ATP our cells create, the more energy can be generated. The raw materials used to make cellular energy are glucose (blood sugar) and "free" fatty acids. The best way to supply your cells with the sugar they need is to consume complex carbohydrates which also supply fiber and other nutrients. When you eat carbohydrates, they are made into glucose which is stored as a starch called glycogen in muscles and the liver. Your body can rapidly turn glycogen into glucose for extra energy. (The process of making energy from glycogen yields carbon dioxide and water as well as ATP.)

Making Energy
The first step in making glucose into energy is called glycolysis. This complicated process requires nine different steps. During these steps, glucose is made into a substance called pyruvate. The process of glycolysis requires ATP, but yields twice as much ATP as is present when it starts.

From here, the process gets a little more complicated as pyruvate enters into a complex chain of events in tiny cellular structures called mitochondria. (Many metabolic events take place in the mitochondria.) The pyruvate molecules are converted to a molecule known as acetyl coenzyme A and eventually made into carbon dioxide, water and more ATP.

This process is known as the Krebs cycle or citric acid cycle. It also involves a series of events known as oxidative phosphorylation in which NADH formed during the Krebs cycle is oxidized to form ATP.

Why is fat such a concentrated source of energy? Free fatty acids enter the Krebs cycle to help generate ATP much more efficiently than glucose - producing roughly six times more energy per gram than glucose.

And Don't Overlook. . .
. . .other supplements that may aid energy production:
• Alpha Lipoic Acid, an antioxidant that works in the fatty tissues of cell membranes and in cells' watery interiors
• Coenzyme Q10, also known as ubiquinone as it exists everywhere in the body, acts like a vitamin because it stimulates some reactions. CoQ10 protects cell membranes, especially of the heart, against oxidation and toxins.

Ginsengs: Energy Generators
With their legendary and slightly mysterious characteristics, the ginsengs are greatly respected natural energy boosters.
" Perhaps no herb has excited so much interest in medical circles as ginseng, and yet, strangely, it does not actually 'cure' any one particular ailment," reports Michael Hallowell, the author of Herbal Healing (Avery) and a frequent lecturer on botanic medicine. "Rather, its virtue lies in its tremendous power as a tonic and invigorator. Russian athletes are prescribed large amounts of ginseng because researchers in Moscow have shown that it not only improves stamina, but also increases the efficiency with which blood is pumped to the muscles."

What are the physiological mechanisms that allow ginseng to bolster your get up and go? In order to unravel the legend and lore of ginseng, the first step is understanding the intricacies of the three types:
• Asian (Panax ginseng), which produces the strongest and most profound stimulation;
• American (Panax quinquefolium), which soothes at a more subtle level;
• Siberian (Eleutherococcus senticosus), a stamina booster embraced by a wide range of athletes.
All three varieties are treasured for their ability to help people adjust to stress.

Biologically Active
The ginsengs are adaptogens, "biologically active substances found in certain herbs and plants that help the body and mind adapt to the changes and stress of life," says Stephen Fulder, MD, author of The Book of Ginseng and Other Chinese Herbs for Vitality (Inner Traditions). "Stress is not an illness in itself. Stress is change, our ability to adapt to all the changes that occur in life, emotional or physical, from exercise, work, chemicals, drugs, food, radiation, bacteria, disease, temperature, or simply too many late nights or too much fun."

The body reacts to stress by producing the hormone adrenaline, which throws the whole body into a state of alert. Metabolism, blood pressure and circulation accelerate; immunity and resistance drastically decline; performance suffers.

Top-Notch Tonics
Enter the ginsengs, with their varied, subtle tonic qualities. The Greek name for this herb, "panax," means "panacea" or cure-all. But the Chinese, who first referred to it 2,000 years ago, more literally called it "ren shen" or "person root," in reference to its physical resemblance to a miniature human form.

" Most exhibit medicinal properties, but each species has a different chemical makeup and has a unique application in Traditional Chinese Medicine (TCM)," says Kim Derek Pritts, author of Ginseng: How to Find, Grow and Use America's Forest Gold (Stackpole). "In general, all true ginseng contains biologically active saponins (chemicals similar to human hormones), essential oils, carbohydrates, sugars, organic acids, nitrogenous substances, amino acids, peptides, vitamins and minerals."

Building Vital Energy
All the ginsengs strengthen, nourish and build Qi, the TCM concept describing basic vital energy circulating through our bodies. Every physical and mental function, from breathing, thinking, nutrition and circulation, is regulated by Qi.
Although many of the Native American tribes used the abundant, indigenous Panax quinquefolium ginseng extensively, particularly to increase mental acuity and boost fertility, the herb never has been as popular in North America as it is in Asia.
American ginseng traditionally has been a lucrative export crop to China, where the wild native variety suffers from overharvesting. Even today, according to Paul Bergner in The Healing Power of Ginseng & the Tonic Herbs (Prima), 95% of the American ginseng crop is exported to China, where XiYang Shen, or "western sea root," as it is called, is immensely valued and costs double what it does here.

Energy Boost
Jacques MoraMarco, author of The Complete Ginseng Handbook: A Practical Guide for Energy, Health and Longevity (Contemporary), as well as a licensed acupuncturist and doctor of Eastern medicine, suggests American ginseng for a slight energy boost. The moderate effect of American ginseng is considered a more appropriate tonic to the intensity of our pace and diet.

Variations on a Theme
In TCM terms, American ginseng cools and moistens, as well as lubricates and strengthens the body. It is reputed to reduce fevers and night sweats and alleviate hot, dry lung problems like smoker's cough. With its emollient qualities, American ginseng is considered to treat dry, wrinkled skin effectively.

The Bolder Energizer
Asian ginseng, which includes red Korean panax, is a bolder energizer taken by those who feel depleted from anemia, blood loss, cardiovascular weakness, injury, shock or trauma, as well as the disabling effects of age. In general, Asian ginseng is warming and stimulating, urging the body to run faster.

Siberian ginseng, though botanically not a true ginseng, still acts similarly to Asian ginseng in its reputed power to control stress, boost energy, support the immune system, enhance performance and increase longevity. Called Wu Cha Seng in Chinese, Siberian ginseng is perceived by natural practitioners as an ideal herb for the healthy who want to lift both stamina and endurance. Experts believe it counteracts the effects of cortisol, the stress hormone produced by the adrenal glands in response to injury, pain or emotional turmoil.

Natural Energy Boosters
The herbal pharmacopeia includes several other natural energy boosters available in various forms-shakes and bars for those on the run-loaded with nutrition absent from commercial snacks. Some choices:
• Ginkgo biloba-used in Chinese medicine to heat the body and increase sexual energy. Ginkgo enthusiasts take this herb to increase the supply of oxygen to the brain and generally increase circulation.
• Gotu kola-may stimulate the central nervous system and help eliminate excess fluid, thereby reducing fatigue.
• Astragalus-a Chinese herb that enhances energy and builds the immune system. It is credited with strengthening digestion, improving metabolism, increasing appetite, combating diarrhea and healing sores.
• Schisandra-also a Chinese herb, treats respiratory illness, insomnia and irritability and rejuvenates sexual energy. Its mild adaptogens help the body to handle stress.
• Licorice-is a favored endocrine toner in Chinese medicine. It is reputed to support the adrenals, the pair of small glands directly above the kidneys that secrete steroidal hormones, norepinephrine and epinephrine, the "fight or flight" hormones. People with high blood pressure or edema, or pregnant women, should avoid it.
• Ashwagandha-an Ayurvedic herb used for thousands of years in the traditional healing of India as a potent strength builder for men and women.

Experienced herbal practitioners acquire an impressive and fascinating store of knowledge and experience-you'll find it helpful to visit one as you begin your course of ginseng or other energy-boosting herbs.

TCM Visitation
When you visit a TCM practitioner, you'll notice that she evaluates your body's condition through an extremely careful examination of all the different systems: Several pulse points are felt in order to ferret out and detect troubling abnormalities. The condition and color of the tongue is observed to decipher digestive disorders. In addition, your urine may be examined to determine other imbalances and specific health problems.

In many cases, your TCM practitioner will recommend ginseng as an adaptogen that can give you an overall boost.
When taking ginseng, follow the directions on the package. Note: in some cases, you may want to consume a little bit less if you suffer headaches, insomnia or high blood pressure. Consult your health practitioner if you are afflicted with either acute inflammatory disease or bronchitis.

Then take comfort in the eternal soothing wisdom of Chinese Traditional Medicine. In the first century A.D., the Shen Nong Ben Cao Jing (The Divine Husbandman's Classic of the Materia Medica) effusively described ginseng and the tonic herbs in this beguiling and intriguing manner: "The first class of drugs...are considered to perform the work of sovereigns. They support human life and they resemble heaven. They are not poisonous regardless of the quality and duration of administration."