The Human body and Strenuous Activities

Long Strain of Activity

Amino Acids

Short Bouts of Activity

Fuel Sources for the body

ATP (adenosine triphosphate)

More energy needed? Creatine Phosphate (CP) is broken down, this is also stored in out muscles.

can only keep muscles active for 1-3 seconds

4 to 6 times as much CP than ATP

not enough for long term activities

carbohydrates and fat are broken down of the energy nutrients for energy to last longer

Activities that last longer than 30 seconds

Body begins to break down carbohydrates and glucose = process called glycolysis

For every glucose molecule that goes through glycolysis, two ATP molecules are produced

Also produces Pyruvic acid

Body breaks down Pyruvic acid into 36 to 38 molecules of ATP

Can Fuel out muscles for 3 min to 4 hrs

During high intensity exercises

Body doesn't inhale sufficient amount of O2 to generate all of the ATP to keep us going

Pyruvic acid is converted into Lactic Acid

for years lactic acid was assumed bad for your muscles

Fat = fuel source for the body = triglyceride molecule

triglyceride molecule = primary storage form of fat in our cells

composed of a glycerol backbone attached to three fatty acids molecules

two major advantages using fat as fuel

Not meant for major fuel source

  1. fat is an abundant energy source
  1. Fat provides 9 kcal of energy per gram whereas carbohydrates provide only 4 kcal per gram.

fat supplies more than twice as much energy per gram as carbohydrate

disadvantage: the breakdown process is slow

should be used as a fuel source for lower intensity and longer duration activities

When training eat carbohydrates

may contribute about 3% to 6% of the energy needed

Most Americans eat more than enough protein (amino acids) to support tissue recovery

If we do not eat enough carbohydrates our body will draw on protein store for energy