lec 14 - iron deficiency + RED-S

Question 1

what is the structure of hemoglobin

Answer 1

4 polypeptide chains (globin)
each of the 4 has a heme molecule with an O2 attached

Question 2

what are the 4 iron containing proteins

Answer 2

ferritin
transferrin
hemoglobin
myoglobin

Question 3

what is ferritin

Answer 3

iron storage protein
found in liver, spleen, and bone marrow
serum ferritin = amount of iron stored in organs

Question 4

what is transferrin

Answer 4

iron binding protein
transports iron in the blood
produced in liver, brain, and testes

Question 5

what is hemoglobin

Answer 5

iron containing protein in RBCs
carries O2 and returns CO2

Question 6

what is myoglobin

Answer 6

iron containing protein in muscles
transports O2 to mitochondria of muscle cells
helps metabolic actions of muscles

Question 7

what are the iron stores in males and females

Answer 7

males = 55 mg/kg
females = 45 mg/kg

Question 8

what is iron deficiency

Answer 8

depletion of bodys iron stores and restriction of iron supply
reduction in the body’s O2 transport capacity
reduction in oxidative capacity at the cellular level

Question 9

is iron deficiency common

Answer 9

yes
prevalence is higher in athletes than gen pop

Question 10

what are the 3 stages of iron deficiency

Answer 10

pre latent iron deficiency (iron storage depletion)
latent iron deficiency (iron deficiency erythropoiesis)
anemia (iron deficiency anemia)

Question 11

what is pre latent iron deficiency

Answer 11

iron stores in the liver, spleen, and bone marrow are depleted
non anemic iron deficiency

Question 12

what is latent iron deficiency

Answer 12

erythropoiesis is impaired
iron supply to cells is reduced
non anemic iron deficiency

Question 13

what is anemia

Answer 13

hemoglobin synthesis falls
anemic iron deficiency
all levels low

Question 14

what are the levels of serum ferritin in all 3 stages of iron deficiency

Answer 14

1. low
2. low
3. low

Question 15

what are the levels of transferrin saturation in all 3 stages of iron deficiency

Answer 15

1. normal
2. low
   3, low

Question 16

what are the levels of hemoglobin in all 3 stages of iron deficiency

Answer 16

1. normal
2. normal
3. low

Question 17

how can you tell if its anemia or not

Answer 17

ID without anemia
- low ferritin but normal hemoglobin
- ferritin = <30ug/L
anemia
- low ferritin AND low hemoglobin (Hb)
- females Hb = <120 g/L
- males Hb = <130 g/L

Question 18

what are the 2 biggest signs of iron deficiency in athletes

Answer 18

fatigue and poor athlete performance

Question 19

what are other signs of iron deficiency

Answer 19

weakness
pale skin
light headedness
cold hands and feet
fast heartbeat
shortness of breath

Question 20

what is the prevalence of iron deficiency

Answer 20

affects 20-25% of the worlds pop
- higher prevalance in developing countries
- higher prevalence of iron deficiency without anemia than iron deficiency anemia

Question 21

what athletes are at risk for iron deficiency

Answer 21

endurance athletes - due to volume of training and amount of food needed to recover
athletes with disordered eating
vegetarians - iron better absorbed from animal based foods
medical conditions

Question 22

what are the exercise induced mechanisms for iron loss in athletes

Answer 22

hemolysis - RBC destruction (travel faster and through more capillaries)
hematuria - RBCs in urine
sweating
GI bleeding
injuries

Question 23

what is the possible treatment for iron deficiency

Answer 23

iron rich diet
iron supplements (side effects associated)
- first step should be diet

Question 24

hwo can you improve iron absorption

Answer 24

pair heme and non heme iron sources
include vit C rich foods with iron irch foods
have iron in the morning, shortly after exercise
- hepcidin (regulates iron levels) is low in the morning

Question 25

what are the 3 components of the female athlete triad

Answer 25

energy availabilty
menstrual function
bone health

Question 26

what is LEA (low energy availability)

Answer 26

mismatch between energy intake and energy expended in exercise
inadequate energy to support the functions required to maintain optimal helath and performance

Question 27

how is energy availability calculated

Answer 27

energy availability = (energy intake (kcals) - energy expenditure (kcals)) / fat free mass (kg)

Question 28

what is the progression of dieting and eating disorders

Answer 28

healthy dieting –> restrictive eating –> abnormal eating behaviour –> clinical eating disorder

Question 29

what is the difference between adaptable and problematic LEA

Answer 29

adaptable is usually short term like making a weight class (mild, benign, minimal or no impact on perf)
problematic presents with signs, symptoms, disruption of body systems, etc

Question 30

what is eumenorrhea

Answer 30

regular cycles between 21-35 days
shouldn’t change more than 6 days between cycles

Question 31

what is primary vs secondary amenorrhea

Answer 31

primary = no periods by age 15
secondary = absence of 3+ consecutive cycles after onset of menarche
- body doesn’t have enough energy to support all systems so it chooses to give hormones and energy to different systems

Question 32

what is oligomenorrhea

Answer 32

cycles longer than 35 days
- 45 days in adolescents

Question 33

what is functional hypothalamic amenorrhea

Answer 33

type of secondary amenorrhea
hormones impacted