Juvenon Health Journal Volume 2 Number 4 – April 2003
Wishful thinkers are often ingenious in their ability to rationalize the avoidance of exercise. Some worry whether too much exercise would wear them out prematurely. Others question whether an older body really needs to break into a sweat. Recent discoveries, combined with a widely accepted theory of aging, clearly counter these rationalizations and document how exercise initiates a coordinated series of responses by the cells of the body culminating in greater strength, energy and stamina.
The mitochondrial theory of aging is widely accepted. It states that cumulative damage to the mitochondria, the power plants in each cell, contributes to physical decline, a wide variety of degenerative conditions, and ultimately to cell death. Maintaining mitochondrial health is therefore essential to successful aging. This is where exercise comes in. Here’s how it works.
The Hard Work?
Recent research with animals has demonstrated that it is possible, at least with some cells, to artificially increase the production of mitochondria without exercise. The authors demonstrated that they could increase the production of mitochondria by introducing a gene to overproduce one of the key regulators of mitochondrial biogenesis, known as CaMK. This research may lead in the future to the production of a drug capable of stimulating CaMK synthesis and consequently mitochondrial production, without exercise. Research on another cellular nutrient, acetyl L-carnitine, shows encouraging results regarding dietary supplementation to support mitochondrial health. Details in next month’s issue.
Exercise, especially aerobic exercise (running, swimming), burns oxygen and consumes fuel (glucose) at a faster rate than can be supplied to the muscle tissue. The muscle responds to this oxygen-nutrient deficit by activating numerous cellular genes to correct the condition. One biochemical factor, HIF-1 (hypoxia inducible factor-1) is activated when the oxygen present in the tissues falls below a certain level, as occurs during strenuous exercise. HIF-1 in turn initiates a cascade of cellular events at the gene level that ultimately promotes the building of new energy supply routes (blood vessels), as well as an increased number of oxygen-carrying red blood cells. The greater the demand (the harder you work the muscle), the greater the size of the newly constructed vascular network.
The worked tissues now have a sufficient supply of fuel to support the new energy demands placed on them. However, yet another important event must occur before the muscle cells can take full advantage of the increased nutrient supply. Rebuilding muscle tissue requires energy, the major source of which is the mitochondria. The more mitochondria a cell possesses, the more capable it is of repairing and rebuilding tissue. Furthermore, the mitochondria impart stamina to the body. The worked muscle therefore requires more of these energy generators, to utilize the increased nutrient supply and build a stronger muscle. Each cell typically carries between 400 and 4,000 mitochondria. The number actually increases in response to exercise.
How does this occur? When a muscle is worked, as occurs with running or lifting weights, it converts the energy stored in the chemical molecule ATP to mechanical energy – e.g., muscle contraction – as well as specific biochemical changes in the cell. The cell is equipped with a sensor that carefully monitors these exercised-induced cellular changes, and it responds by promoting the activation of key regulators of mitochondrial biogenesis. These regulators turn on the multiple genes required for construction of new mitochondria. So the worked muscle now has both an increased supply of nutrients as well as more powerhouses to convert the nutrients to energy for new muscle synthesis.
What happens to the cells when we don’t exercise? With age, our mitochondria normally decrease in number and robustness. The decrease interrupts the ability of the cell to perform its normal functions. (This deficiency is even more pronounced with age-associated pathologies, including Alzheimer’s, Parkinson’s, and other neurodegenerative disorders.)
The early portion of our lifespans is characterized by vigorous growth of cells and cellular components, such as mitochondria. As we age, degenerative processes occur as a result of an accumulation of errors induced by free radical attacks on key cellular components, including genes, mitochondria and other cellular structures. The consequence of these attacks is old, worn-out and distorted cellular molecules (cellular garbage). The cell must remove the impaired molecules, which interfere with normal cellular activity. This process requires energy, and exercise helps the cell produce the energy required to remove the garbage, as well as inhibit the production of cellular garbage.
Although these degenerative processes are inevitable (at least at present), they can be attenuated by a healthy life-style and, most emphatically, exercise. The loss of mitochondria is a hallmark of the aging process, one that manifests itself as a loss of mental clarity, strength, vigor and endurance. Exercise, via the mechanism described above, can offset these effects by replenishing the cellular mitochondria, restoring the cell to a more youthful state.
Thus we see that regular physical activity results in a chain of cellular benefits. Energy production, blood flow and cellular efficiency all increase. Regular physical activity promotes leanness by stimulating the burning of fat for energy. We feel these benefits in the form of greater strength and stamina, and often an enhanced sense of well-being and mental clarity.
This issue completes a two-part series on
positive effects of exercise on aging bodies.
Dr. Treadwell answers your questions about Juvenon™ Cellular Health Supplement
QUESTION: I’m very active, exercise a lot and participate in competitive events that are physically demanding. Will the Juvenon product provide additional protection to my health?
B.L., via email
ANSWER: Strenuous physical exercise has a positive effect on overall health. However, it does increase the production of oxidants that can damage tissue. It also places increased demand on the mitochondria to produce more energy. The body responds to the stress by increasing its oxidant defense system and producing more mitochondria. Nevertheless, it could use additional help.
Juvenon Energy Formula™ contains compounds that support the body’s oxidant defense system. These compounds have been demonstrated to promote the production of a key structural component (cardiolipin) in the mitochondria. Cardiolipin functions as a scaffold for the mitochondrial machinery involved in energy production. An inadequate level of this component will result in lower energy. Thus, although the body responds to oxidant stress by increasing its antioxidant defense, the compounds present in the Juvenon formula add additional protection.
Benjamin V. Treadwell, Ph.D., is a former Harvard Medical School associate professor and member of Juvenon’s Scientific Advisory Board.