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Nutrition and Health
There are six main nutrients in which the body needs to receive.
These nutrients include carbohydrates, proteins, fats, vitamins,
minerals, and water. It is important to consume these six nutrients
on a daily basis to build and maintain healthy body systems.
Ill health can be caused by an imbalance of nutrients, producing
either an excess or deficiency, which in turn affects body
functioning cumulatively. Moreover, because most nutrients are, in
some way or another, involved in cell-to-cell signalling (e.g. as
building block or part of a hormone or signalling 'cascades'),
deficiency or excess of various nutrients affects hormonal function
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indirectly. Thus, because they largely
regulate the expression of genes, hormones represent a link between
nutrition and how our genes are expressed, i.e. our phenotype. The
strength and nature of this link are continually under
investigation, but observations especially in recent years have
demonstrated a pivotal role for nutrition in hormonal activity and
function and therefore in health.
Nutrition and sports
Nutrition is very important for improving sports performance.
Contrary to popular belief, athletes need only slightly more protein
than an average person. These needs are easily met by a balanced
diet, and the recommended daily servings are generous enough to meet
these needs. Additional protein intake is broken-down to be used as
energy or stored as fat. Excess protein or grain consumption in the
absence of alkalizing mineral intake (from fruits and vegetables)
leads to chonic low grade acididosis in which calcium and glutamine
are leached from bone and muscle respectively to keep the blood pH
steady.
Endurance, strength and sprint athletes have different needs. Many
athletes may require an increased caloric intake.
Maintaining hydration during periods of physical exertion is key to
good performance. While drinking too much water during activities
can lead to physical discomfort, dehydration hinders an athlete’s
ability. It is recommended that an athlete drink about 400-600mL 2-3
hours before activity, during exercise he or she should drink
150-350mL every 15 to 20 minutes and after exercise that he or she
replace sweat loss by drinking 450-675 mL for every .5 Kg body
weight loss during activity. Studies have shown that an athlete that
drinks before they feel thirsty stays cooler and performs better
than one who drinks on thirst cues.Additional carbohydrates and
protein before, during, and after exercise increase time to
exhuastion as well as speed recovery. Dosage is based on work
performed, lean body mass, and environmental factors (heat).
The main fuel used by the body during exercise is carbohydrates,
which is stored in muscle as glycogen- a form of sugar. During
exercise, muscle glycogen reserves can be used up, especially when
activities last longer than 90 min. When glycogen is not present in
muscles, the muscle cells perform anaerobic respiration producing
lactic acid, which is responsible for fatigue and burning sensation,
and post exercise stiffness in muscles. Because the amount of
glycogen stored in the body is limited, it is important for athletes
to replace glycogen by consuming a diet high in carbohydrates.
Meeting energy needs can help improve performance during the sport,
as well as improve overall strength and endurance. |
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