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Brady Yoon
2005-Apr-07, 09:32 PM
There was a question on a Science Olympiad test I took, and I didn't know how to do it.

The question is:

Margie, age 18, body weight 117 lb, is a fitness runner. She ran the mini marathon (13.1 mi.) at an 8.5 minute per mile pace. We know from treadmill testing that this running pace is around 10.8 METS for her. With this information, answer questions #1 and #2.

1. What is her maximal oxygen uptake (milliliters per kilogram per minute) if we know her 8.5 minute pace is at 70% max VO2?

Ok, for this one, I started by making a proportion, saying that:

70/100=10.8 METS/x

x=15.43 METS, so if she was running at full speed, she would be using energy at 15.43 times her basal metabolic rate. However, that's where I got stuck.

2. How many calories will she use for the entire distance?

Same here.

Thanks for all the help. I would think about it a little more but I have to go to lunch.

8)

Brady Yoon
2005-Apr-08, 04:34 AM
Bump.. :x

Eroica
2005-Apr-08, 11:41 AM
Margie, age 18, body weight 117 lb, is a fitness runner. She ran the mini marathon (13.1 mi.) at an 8.5 minute per mile pace. We know from treadmill testing that this running pace is around 10.8 METS for her...

2. How many calories will she use for the entire distance?

Pounds, miles, milliliters, kilograms - they sure like to mix their metrics with their imperials!

I don't know if this is the method you're supposed to be using. Margie's age and sex do not come into my calculations, so ... ? It might help if we knew what sort of problems you've been solving and what methods you've been using.


Her running pace is 10.8 METS

1 MET = 3.5 ml of O2 per kg per min

At 8.5 mins per mile, it takes her 111.35 mins to run the half-marathon

Her body-weight is 53.07 kg

So:

(10.80)(3.5)(111.35)(53.07) = 223,373.2221 ml or about 223.37 litres of oxygen consumed during the race.

Now, the caloric value of oxygen consumed depends on which type of food is being metabolized (fat, protein or carbohydrate). For all-fat the value is 4.686 cals; for all-carb it's 5.047. Let's just say 5.0.

(223.37)(5) = 1116.85 calories

:-k

(The phpBB turned (10.8) into a smilie!)

Brady Yoon
2005-Apr-09, 03:40 AM
Margie, age 18, body weight 117 lb, is a fitness runner. She ran the mini marathon (13.1 mi.) at an 8.5 minute per mile pace. We know from treadmill testing that this running pace is around 10.8 METS for her...

2. How many calories will she use for the entire distance?

Pounds, miles, milliliters, kilograms - they sure like to mix their metrics with their imperials!

I don't know if this is the method you're supposed to be using. Margie's age and sex do not come into my calculations, so ... ? It might help if we knew what sort of problems you've been solving and what methods you've been using.


Her running pace is 10.8 METS

1 MET = 3.5 ml of O2 per kg per min

At 8.5 mins per mile, it takes her 111.35 mins to run the half-marathon

Her body-weight is 53.07 kg

So:

(10.80)(3.5)(111.35)(53.07) = 223,373.2221 ml or about 223.37 litres of oxygen consumed during the race.

Now, the caloric value of oxygen consumed depends on which type of food is being metabolized (fat, protein or carbohydrate). For all-fat the value is 4.686 cals; for all-carb it's 5.047. Let's just say 5.0.

(223.37)(5) = 1116.85 calories

:-k

(The phpBB turned (10.8) into a smilie!)

Hey, thanks for the help. Didn't exactly know what a MET was I guess...

Anyway, here's another question. I'm reading about how the heart works, and there is a vocab word called "action potential."

It says: A conducted change in the transmembrane potential of excitable cells, initiated by a change in the membrane permeability to sodium ions.

Am I close in saying that its an electrical impluse that allows sodium ions to travel from one side of the cell to another, thus changing its electrical charge?

Eroica
2005-Apr-09, 10:57 AM
Didn't exactly know what a MET was I guess...
MET = Metabolic Equivalent Unit. One MET = oxygen intake at rest = approximately 3.5 ml of oxygen/kg body weight/minute.


Anyway, here's another question. I'm reading about how the heart works, and there is a vocab word called "action potential."

It says: A conducted change in the transmembrane potential of excitable cells, initiated by a change in the membrane permeability to sodium ions.

Am I close in saying that its an electrical impluse that allows sodium ions to travel from one side of the cell to another, thus changing its electrical charge?
Sounds right to me, but I'm no expert.

Is there a doctor in the house? :D