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Unless
You Balance Acidity
Your
Muscles May Become Tense
by
Frank Murray, Sports Nutrition
Your
muscles are designed to work well only in a narrow range of almost
zero acidity, according to Michael Colgan, PhD, in Optimum Sports
Nutrition. Arterial blood works best with no acid at all. Acidity is
measured by the concentration of hydrogen ions (pH). A pH of 7.0 is
neutral, midway between very acidic (pH of 1) and very alkaline (pH
of 14), he explained.
"The
pH skill is water arithmetic, like the skill of earthquakes,"
Coleman said. "So small changes in the numbers mean large
differences in acidic E or alkaline 80. A pH of 6 is Ten times more
acidic than a pH of 7. At rest, muscle pH is about 6.9, while
arterial blood is about 7.4."
As
you begin to exercise, he continued, the increased use of muscle
glycogen for energy produces lactic acid and pyruvic acid, to
substances which contain a lot of hydrogen ions (H+), which drive
muscle and blood pH down into the acid zone. (Incidentally, pH is
derived from the French pouvoir hydrogene, meaning hydrogen power.)
Colgan
goes on to say that the harder you exercise, the quicker you
"go acid." When muscle pH drops below 6.5, the acidity
disrupts all sorts of links in the energy chain. For example, the
enzyme phosphofructokinase is the rate limiting step in muscle use
of glycogen. Below pH 6.5, it stops working altogether. And, he
says, acidity also reduces muscle power directly by inhibiting the
contractile action of muscle fibers.
"So,"
Colgan added, "The first thing that a successful ergogenic
supplement has to do is reduce the accumulation of acidity in
exercising muscle. You can put all sorts of other chemicals into the
bloodstream, but, unless you reduce acidity during exercise, your
muscles will tie up."
Another
inhibitor of exercise, Colgan said, happening simultaneously with
the accumulation of acid, is the accumulation of ammonia; anaerobic
and endurance exercise produces a lot of it. Ammonia is toxic to
cells, it reduces the formation of glycogen, and it inhibits the
energy cycle.
He
adds that, although we still do not know how much ammonia
contributes to fatigue, we do know that the higher your blood
ammonia, the poorer your performance.
Immediately
after marathon races, triathlons or other endurance events, some
athletes have very low blood phosphate levels, Colgan said.
Even athletes with high resting phosphate levels show marked
reductions after endurance exercise.
"How
does this loss of phosphate damage performance?" Colgan asked.
"First, there is a loss of acid buffering. Phosphate is a major
alkaline buffer of muscle. Second, to make new muscle glycogen, your
body has to use pyridoxal phosphate, a mix of phosphate and vitamin
B6."
Since
many people, including athletes, do not consume enough alkaline rich
foods, such as fruits, nuts and vegetables, but instead rely heavily
on acid forming foods, such as meat, fish, poultry, eggs, etc., they
may be at risk for an acidic condition in their body fluids. |
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