Resolved Help with Numbers Formula

[SpongePudding]

Hello one and all,

The formula below, which I copied from the web, calculates VO2 max based on time.
By replacing 'time' in the formula with value (e.g. 52:33) the result should be 37.744. I have tried (using EXP ), but without success. I'm no mathematician so any help would be much appreciated.

(percent max = 0.8 + 0.1894393 * exp(-0.012778 * time) + 0.2989558 * exo(-0.1932605 * time)

PS: I'm using a MacBook Air M1 2020

Thank you in advance

 

[chabig]

There are some symbols and values in your formula that don't match what you typed in your post. Also, you've got time in the form of mm:ss. You can't use that form in mathematical computations. It has to be converted to the proper decimal fractions in the correct units. For example, 52 minutes and 33 seconds is 52.533 minutes.

Where did you find that formula? Can you post a link?

 

[SpongePudding]

Good spot. Not sure how the '+' signs & 32:32 got there, but I've now removed them (see attached).
B35 = 52:33

 

[chabig]

Good job. Now figure out the proper units for time. Even then, the formula looks like it's just going to produce some small number slightly greater than 0.8 and less than 1.0, which makes no sense as an answer for VO2 Max.

 

[SpongePudding]

B35 is set as a Duration, see attached. Is that not the correct format?

 

[SpongePudding]

For clarity 'time' is the race time, in my case 52mins 33secs (52:33) or (52.55 as a decimal)

 

[NoBoMac]

You can't use that form in mathematical computations. It has to be converted to the proper decimal fractions in the correct units. For example, 52 minutes and 33 seconds is 52.533 minutes.

This.

In Excel/LibreOffice, to convert to proper units would be =time*24 for hours, =time*1440 for minutes, =time*86400 for seconds.

For Numbers: =hour(time)+(minute(time)/60)+(second(time)/3600)

But as @chabig mentioned, would help to provide source to the formula, as does not look like it's correct formula. Closest one I've seen uses age, BMI, time. And in that one, time is multiplied with one value, squared in another, not exponent function.

 

[SpongePudding]

As I mentioned in the beginning I'm not math mathematician and thought it would be simply a matter of replacing the text 'time' with a numerical value. I've just copied the 3 formulas that give me the 3 sets of data I need (see attached);
The formulas are:

• percent max = 0.8 + 0.1894393 * exp(-0.012778 * time) + 0.2989558 * exo(-0.1932605 * time)
• VO2 = -4.60 + 0.182258 * velocity + 0.000104 * velocity² (I've worked this one out)
• VO2 MAX = VO2 / percent max (this one is the result of dividing VO2 by percent max)

where time is the race time, and velocity is race velocity in meters / minute.

 

[SpongePudding]

There are some symbols and values in your formula that don't match what you typed in your post. Also, you've got time in the form of mm:ss. You can't use that form in mathematical computations. It has to be converted to the proper decimal fractions in the correct units. For example, 52 minutes and 33 seconds is 52.533 minutes.

View attachment 2000458

Where did you find that formula? Can you post a link?

Here's the link the link: https://www.omnicalculator.com/sports/vo2-max-runners#vo2-max-calculation-jack-daniels-formula

 

[SpongePudding]

There are some symbols and values in your formula that don't match what you typed in your post. Also, you've got time in the form of mm:ss. You can't use that form in mathematical computations. It has to be converted to the proper decimal fractions in the correct units. For example, 52 minutes and 33 seconds is 52.533 minutes.

View attachment 2000458

Where did you find that formula? Can you post a link?

I've just found this:

percent_max = 0.8 + 0.1894393 * e^(-0.012778 * time) + 0.2989558 * e^(-0.1932605 * time)

 

[chabig]

I've confirmed a few things.

1. Numbers won't do math with durations. Use the function DUR2MINUTES to convert your duration to a numerical value. After you do that, your first formula will correctly calculate the percent max.
2. You've incorrectly used the Percent Max formula in the line labelled VO2 Max.

You must calculate both VO2 Race and Percent Max first, then VO2 Max is calculated from those.

I recreated your spreadsheet with the correct formulas, converted duration to minutes, distance to meters, and calculated velocity in meters/minute. I get the same results as that web page.

 

[SpongePudding]

I've confirmed a few things.

1. Numbers won't do math with durations. Use the function DUR2MINUTES to convert your duration to a numerical value. After you do that, your first formula will correctly calculate the percent max.
2. You've incorrectly used the Percent Max formula in the line labelled VO2 Max.

You must calculate both VO2 Race and Percent Max first, then VO2 Max is calculated from those.

I recreated your spreadsheet with the correct formulas, converted duration to minutes, distance to meters, and calculated velocity in meters/minute. I get the same results as that web page.

View attachment 2000533

That's awesome, thank you, much appreciated

 

[SpongePudding]

That's awesome, thank you, much appreciated

Cracked it! - thank you for spotting my errors! - I followed your guidelines and . . . success

 

[chabig]

Very nice!

 

[SpongePudding]

Very nice!

Thank you for all your support