nisms and the well-established beneficial effects
of CHO supplementation on the contracting
muscle.
The potential role of tyrosine supplementation
to increase or maintain noradrenaline and dopa-
mine as a way to offset CNS fatigue is theoreti-
cally feasible, but there is essentially no direct
evidence to support this hypothesis at this time.
The potential role of choline supplementation
to prevent ACh depletion and neuromuscular
transmission failure is even more tenuous.
Future research on possible relationships
among nutrition, brain neurochemistry and
fatigue is likely to lead to important discoveries
that may enhance physical and mental perfor-
mance during sports participation and, although
not addressed in any depth in this review, during
activities of normal daily life. It may also help
to understand and better treat the debilitating
fatigue that often occurs in patients with chronic
fatigue syndrome, fibromyalgia, viral illness and
depression, among others.
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