module 9 mcc sports nutrition credit course - micronutrients and exercise
TRANSCRIPT
MODULE 9 - MICRONUTRIENTS AND EXERCISE
WHAT ARE MICRONUTRIENTS
Micronutrients - Vitamins and minerals
They do not produce energy themselves but are involved in processes that help in energy production.
They are needed only in small quantities in the body.
Deficiencies and excesses can affect health.
VITAMINS
Organic substances
Produced by plants during photosynthesis
Provitamins are inactive precursors to vitamins
Classified as WATER soluble and FAT soluble
WATER SOLUBLE VITAMINS
Mostly act as coenzymes
Disperse easily in body fluids
Excess is excreted in the urine
Deficiencies can develop in about 4 weeks of inadequate intake
FUNCTIONS OF WATER SOLUBLE MICRONUTRIENTSName
Function
Food Sources
FAT SOLUBLE VITAMINS
Dissolve and stored in body's fatty tissues
Should not be consumed in excess - toxic
Not easily excreted from the body
FUNCTIONS OF FAT SOLUBLE VITAMINS
Functions Of Vitamins
MINERALS
Consist mostly of metallic substances
Essential for life - balanced diet provides sufficient minerals
Provide structure - formation of bones and teeth
FUNCTIONS OF MINERALS
Minerals & Exercise
• Excessive sweating during exercise causes loss of body water and related minerals.
• Mineral loss should be replaced following exercise through well-balanced meals.
• Single-mineral supplementation is ill advised unless prescribed because of potential adverse consequences.
a) ENERGY YIELDING NUTRIENTS
B Vitamins and Energy Metabolism
B-vitamins participate in energy metabolism (releasing energy from nutrients)
Athletes with high energy expenditures have increased requirements for B vitamins. However, eating more food (energy intake that achieves energy expenditure) provides the extra B-vitamins that are needed.
Vitamin/mineral deficiencies impair physical performance, physical work capacity, endurance, oxygen consumption, cardiovascular function, muscle strength, or resistance to fatigue.
b) VITAMINS AND MINERALS FOR BLOOD FORMATION
Iron is required for a number of key functions in the body:• Iron is an important in transporting oxygen in the blood and in
the muscles.
• Iron is involved in the electron transport system. This system controls the release of energy from cells.
• Iron is required for red blood cell production.
• Iron is required for a healthy immune system
IRON AND EXERCISE RELATED FUNCTIONS
IRON SOURCES
Iron is widely distributed in food but the rate of absorption differs.
Plants contain NON-HEME iron(absorption <5%)
Meat contains HEME iron (15 - 18%)
IRON AND EXERCISE RELATED FUNCTIONS
Most of the iron in the body is combined with Haemoglobin
Iron deficiency leads to ANAEMIA causing sluggishness, loss of appetite, decreased ability to sustain activity
Anaemia negatively affects aerobic exercise and ability to perform heavy training
SORTS ANAEMIA
Hard exercise results in an increase in the volume of plasma in the blood.
This can dilute haemoglobin levels and incorrectly suggest that there is a problem with iron status.
This condition is known as ‘sports anaemia’.
It is most likely to occur in the early stages of a training program or when training load is increased.
c) ANTIOXIDANT MICRONUTRIENTS
ANTIOXIDANT ROLE OF VITAMINS
Free radical : Highly reactive atom/ molecule that contains at least one unpaired electron.
Antioxidant : Prevents the oxidation of other molecules.
Thereby preventing cellular damage.
Vitamins A, C, E and beta carotene are powerful antioxidants
Why do athletes need antioxidants?Aerobic activity metabolism increases the production of free
radicals
Pentane is produced during exercise (as a result of lipid peroxidation) and if not removed from the body can have adverse effects on the pulmonary system function
Exercise & Immunity
Exercise, stress and illness have an effect on immunity.
Moderate exercise boosts the body's immune defenses to last for a couple of hours.
Exhaustive exercise for a long period of time severely affects the body's first line of defense (immune system) against infection.
Activity:
Find the foods that are rich in antioxidants(word puzzle)
d) OTHER MICRONUTRIENTS AND INFLUENCE
CALCIUM AND OSTEOPOROSIS
Osteoporosis is the loss of bone density
Osteopenia is a midway condition where bones weaken and risk of fracture is increased
Adequate calcium intake and weight-bearing exercise prevent bone loss
OSTEOPOROSIS RISK FACTORS
Phosphorus:
Essential component of ATP
Combines with lipids to form phospholipids
Regulate cellular metabolism
Magnesium:
Vital role in glucose metabolism - break down to produce energy
Synthesis of lipids and proteins
Function of nervous system
Minerals & exercise
Strenuous exercise may lead to the loss of these four trace elements:
1. Chromium2. Copper3. Manganese4. Zinc
Functions of Copper:
• Help your body utilize iron
• Reduce tissue damage caused by free radicals
• Maintain the health of your bones and connective tissues
• Help your body produce the pigment called melanin
• Keep your thyroid gland functioning normally
• Preserve the myelin sheath that surrounds and protects your nerves
Functions of Chromium:
• Help maintain normal blood sugar and insulin levels
• Support normal cholesterol levels
Functions of Zinc:
• Help balance blood sugar
• Stabilize your metabolic rate
• Prevent a weakened immune system
• Support an optimal sense of smell and taste