CrossFit

shellee9tj

Hi there! Anyone know how to calculate calories burned from a CrossFit class?
Thanks!
~Michelle

BrittneyBroussard

Best bet would be to get a fitness watch buuut if u google there are some sites that help u calculate the diff moves...it won't be super accurate though bc it prob goes of a typical body weight but itll be something vs nothing...i did it for box jumps last week

heybales

HRM calculated calorie burn will be worthless and inflated for all the workouts occurring in Crossfit.

The only valid exercise for the calculations is stead-state aerobic, same HR for 2-4 min.

Your lifting is anaerobic, and the whole class I doubt has your HR steady for more than 5 seconds, perhaps during warmup aerobic.

You could track the time for a typical week, and then apply that to every workout for averages.

Time how long the purely lifting part is - that's reps and sets and rests of 2-4 min.
That is logged as Strength Training in database. It's low, but that's true.
But you probably don't do that for that long.

Now time the other parts - if a warmup/cooldown aerobic is normally done, time it. If biking then Watts may be given, which can be converted to calories.

Time the other activity now.
Log that as Circuit training. Which is higher than lifting, but that's minimal rests, and usually higher reps.

Once you have time a weeks worth of workouts, average the time for each thing.
Then go log each thing - and see what the calories are for each - add them all up.

Now you can create a workout called Crossfit - and use that average time and calorie burn each time.

Ya, it's a lot of work, but only have to do it one week - then simple.

antennachick

circuit training is similar

MilesAddie

This is a tough one. By definition, CrossFit workouts are constantly varied and changing - you shouldn't repeat a WOD in a couple years, with the exception of Benchmark WODS or Hero's. Some WOD's are heavy on oly lifting, some heavy on steady cardio, some on gymnastic movements. And then some WOD's are for time, some are AMRAP, some are TABATA, etc. There are a lot of factors to consider.

What I've found common is that people will assign a number of calories to the number of minutes in the WOD. For me right now, thats 1 to 1, but when I get to my goal weight, I will up that to 10 to 1 and see how that goes.

However one study found that men doing 'Cindy' which is a 20 minute bodyweight AMRAP, burned an average of 13 calories a minute.

heybales

If that study has the VO2max of the people that burned 13/min - then they can come up with a METS value, that could be used by anyone else for decent estimate.

"men" and "13 cal/min" isn't enough useful info for even other men frankly.

MilesAddie

So like I said, assign a calorie count per minute that you are comfortable with. For me, as I am trying to lose weight and don't want to overestimate my caloric burn, that is 1 to 1. As I transition to maintenance, I'll slowly raise that number until I see empirical results in line with my goals.

The study was thrown in as an anecdotal statement, it was not the point of my post.

heybales

Considering BMR for smaller lady would be 1.13 if sleeping for that time, probably could estimate a tad higher and still be on safe side.

Good plan to adjust with evidence, and I guess that would include workouts becoming too difficult with lack of energy, or recovery being poor?

I knew study comment was side comment, merely pointing out if they did it right (which some don't) - they could provide useful to others info from the study.

MilesAddie

@heybales

Yeah, I couldn't find the whole study in a format to read, but I don't have access to LexisNexis or another academic research tool from home, if you do, or if you have more patience in web sleuthing, I am sure you could find it. The author has published more than a few studies that, considering the specificity of your comments, I think you would find interesting. Things like "Effects of a high-intensity interval training program vs. moderate-intensity continuous training program on maximal oxygen uptake and blood pressure in healthy adults ". Details follow.

Dr. Yuri Feito, Ph.D., M.S., MPH
Professor of Exercise Science
Kennesaw State University
Fellow, American College of Sports Medicine

Study was released in 2014 or 2015.

I read a few of his articles in the Baltimore Sun and WaPo - they we're OK.

Also, not quite sure what you meant by the "lack of energy, or recovery being poor" comment, so I'll say this in response to what I think you're getting at. If I find my fitness performance slipping, soreness and cramping increasing past a point that I'm comfortable with, or if my emotional health seems to be suffering, I will be upping my calorie intake. Losing weight will not come at the expense of my physical performance, health, or happiness.

Cheers

MaryYoungmark

I typically log mine as calisthenics 10-25 minutes depending on the intensity and length

heybales

Cool that Dr is doing so much study on it.

Found one that was interesting too, countering the claim it wasn't a good enough workout compared to P90X.
https://minds.wisconsin.edu/bitstream/handle/1793/66173/Babiash_Paige_Thesis.pdf?sequence=1

The first WOD (Donkey Kong) incorporated the following exercises: burpees, kettlebell swings, and box jumps. Each
exercise was performed three times, with the number of repetitions decreasing each time.
During the first round each exercise was performed 21 times, the second round 15 times, and the final round 9 times.
The second WOD (Fran) contained just two exercises: thrusters and assisted pull-ups.
This WOD was performed in the same sequence as the first. These WODs are based on the idea of completing all of the repetitions in the shortest amount of time possible.

When this was done, caloric expenditure averaged 20.5 kcal/min in men and 12.3 kcal/min in females.

male BMR - 1897 / 1440 = 1.317
female BMR - 1482 / 1440 = 1.029

male - 20.5 / 1.317 = 15.6 METS
female - 12.3 / 1.029 = 12.0 METS

So for those types of workouts which are intense cardio compared to the straight lifting aspect of Crossfit.

You would take your BMR / 1440 = BMR calories per min x minutes of the activity x METS = calorie burn.

The straight lifting would still be logged as Weight Training time.

Which can't be logged in a study such as this using VO2max equipment.
Must be performed in a metabolic chamber to actually measure the heat increase, which is what a calorie is really.
That heat increase after usually doing a set is then calculated out to how much was burned, worked backwards to METS like above. Which is 3.5 METS on average.

So that figure above much higher for male and female compared to Circuit training which is 8 METS.

MilesAddie

Thank you for posting that. I've done both of those wods. Fran many times. She can be a killer. Enjoyed the chat. Be well.