Sports and Nutrition: Fluids and electrolytes

body mass loss greater than what amount will impair aerobic exercise

• >2% fluid loss

what can progressive dehydration result in

• impaired thermoregulation

• impaired aerobic exercise performance

• external heat cramps (full body cramping)

radiation

• heat loss by giving off from body into environment

conduction heat loss

• heat lossed by direct physical contact causing heat disposition

• ex: rowing, wrestling

Convection heat loss

• movement of air or water over individuals whole body that acts as cooling affect

• ex: swimmers

Vaporization of heat loss

• evaporation of sweat off skin

• accounts for more than 80% of water loss when hot

sweat rate variables

• intensity/duration of time/ type of exercise

• climate/temp and acclimation to them

• hydration level

• clothing/surface were competing in

What results if we are not acclimated to weather during exercise

• will result in sweating sooner to start cooling our bodies faster and loss of less sodium

• lower core level heart rate and sodium loss

• higher sweat and blood volume

what is the result of we are not fully acclimated to weather were exercising in

• sweat less causing slower cooling and more sodium loss

• higher: core temp, HR, and sodium loss

• lower: sweat and blood volume

what type of mineral is mostly lost in sweat

• sodium and chloride

how is gastric emptying maximized

• the amount of fluid in the stomach (more fluid = more emptying)

• less than 10% CHO solution

dehydration definition

• losses of fluid exceed intake its a process

• measured over a long period of time

hypohydration

• low body water volume

• static measure in one specific time

hyponatremia

• due to heavy sweating or excess water

• high levels of water will cause water to move from outside the cell into the cell resulting in swelling (cerebral and lung cells mostly)

• low blood sodium high water levels

fluid and electrolyte recommendation for before exercise

Fluid:

• 4 hrs: 5-7 mL/kg

• not adequately hydrated, 2-3 hrs: 3-5 mL/kg

Electrolyte:

• sodium: 20-50 mEq/L

fluid and electrolyte recommendation for during exercise

fluid:

• runner: .4 -.8 L/hr (13-27 oz/hr)

• over 90-120 mins: CHO solution

• under 90-120 mins: water

electrolyte:

• sodium: 20-30 mEq/L

• potassium: 2-5 mEq/L

after exercise fluid and electrolyte recommendation

fluid:

• 1.5 L/kg weight lost

electrolyte:

• sodium: 15-30 mEq/L

• also pair with salty foods!

goal of after exercise fluid intake

• correct fluid losses that happened during exercise

goal of during exercise fluid intake

• maintain fluid balance and prevent excessive dehydration

well hydrated body weight changes number

• <1% decrease

minimal dehydrated body weight loss number

• 1-2% decrease

significant dehydration body weight loss number

• 3-5% decrease

steps to create individualized hydration plan

• assessment

• goals

• action

• reassessment

assessment of sweat rate steps

1. record pre exercise weight

2. record post exercise weight

3. take pre exercise weight - post exercise weight

4. convert lbs from #3 to oz

5. record amount of fluid in oz consumed

6. record amount of urine excreted in oz

7. add #5 + #4 then - #6

8. divide #7 by minutes of exercise to find sweat rate per min

9. then multiple #* by 60 mins to find sweat rate per hr