In Rest Day/Theory

February 18, 2010

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Calculating the power output of a workout in foot-pounds per minute can be interesting, but does it really tell us anything about improving fitness?

Power is intensity, and intensity brings results.

In CrossFit, we maximize intensity by using a stopwatch. We apply this stopwatch to a wide variety of functional movements performed with full range of motion. More than any other single factor, this practice is responsible for the unprecedented results of our athletes. Therefore, many believe it logically follows that measuring power will allow us to maximize intensity, and thus results.

Unfortunately, this simply isn’t true because life demands the completion of tasks, not the maximization of power. There is an irony here. Measuring the physical power output of our workouts in terms of foot-pounds per minute is mostly irrelevant to the success of our efforts even though maximizing power output is vital. This distinction may appear contradictory at first but is nonetheless tremendously important.

Counting your reps, weighing your barbells, and timing your workouts is really all you need. If you complete the same workout in less time or do more work (reps) in the same time, you have increased the average power in real terms. No other data is required to maximize results.

Many in the CrossFit community, including Coach Glassman, have dug into measuring the power outputs of different athletes in different workouts. The overwhelming conclusion of these analyses is that tracking times and loads provides as much data as we need to develop elite levels of fitness. Secondly, these investigations concluded that calculating actual foot-pounds per minute didn’t contribute any additional benefit toward that fitness.

In other words, cutting your Fran and Helen times, increasing your max deadlift and getting more rounds of Cindy or Mary is really all you need to know about power. Knowing that you can generate over 20,000 foot-pounds per minute in Fran but just under 10,000 foot-pounds per minute for Elizabeth provides no additional benefit.

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23 Comments on “The Importance of Power, and the Irrelevance of Measuring Power ”


wrote …

"If you complete the same workout in less time or do more work (reps) in the same time, you have increased the average power in real terms. No other data is required to maximize results."

It can even be more subtle than that too, for example the "same" in "same workout" better really mean it, because if I do 10 reps now, but did 9 reps before, if I had crummy form or cheated that weight all around to get the 10 reps it may not be better than the 9 reps.



Jeff Barnett wrote …

Excellent article, Russell. I can admit to geeking out over power output calculations, but for all but the simplest workouts it becomes nightmarishly complex. As you allude, it's an interesting mental exercise, but not terribly relevant to our mission of increasing work capacity over broad time and modal domains.


wrote …

I've read this twice now, and while I agree that real world application of CF requires only enough attention to complete the task in front of us, I still think that measuring total power output for your workouts is much more meaningful than given credit for in this article.

First, our definition of fitness is broad, general and inclusive, so I don't think anyone is looking to neglect the slow, deliberate and skill oriented tasks in favor of just maximizing snatches and thrusters. When Coach presents those graphs of functional work capacity at lectures the x-axis is always duration of the workout and the "fitness" curve extends out past the 5 or 10 minute mark. I believe the contention is that if we can raise that curtain and maximize the space underneath the curve, we increase our work capacity across broad time domains (hence why some workouts are designed to be 20-25 minutes and others under 5).

Furthermore, when it comes to client feedback, I think measuring power output can be tremendous. If you go to any body building gym, they measure success and progress by measuring body fat percentage, weight and girth measurements. The problem I've run into with utilizing these measures is that they don't provide any meaningful differences between workouts. Industry standards suggest that you wait a month between body fat measurements because skinfold measurements have a 2-4% error rate. Whereas, if I can calculate how much work you've been doing and put it in a graph that represents your work capacity history, and then I calculate today's workout and plot it on the same graph, I can determine whether today's workout was positive and progressive, or negative and regressive. The benefit of knowing that quickly is so that we can identify negative externalities (i.e. what foods you ate, how much sleep you got, stressors from spouses, kids, etc.) and work to reduce those things so your workouts continuously improve your fitness. If we just followed along with the idea of comparing Fran times to previous Fran times, we find ourselves in a similar situation the globo-gyms do, which is meaningful comparison to last month's results, thereby necessitating a measure of comparison across variable time and modalities. The biggest issue becomes equalizing work in different planes of movement. It is simple to compare two exercises when it comes to vertical distance, but what about horizontal distance and circular movement (like a kipping pull up or a kettlebell swing).

Currently, I'm employed at 24 Hour Fitness, but all of my clients do constantly varied functional movements at high intensities measured by a stopwatch. But when they finish with a workout that isn't a benchmark workout and they feel like they've killed themselves, all they want to know is whether that time was good. It's hard to tell them it wasn't but I often find myself thinking that they could have pushed a little harder (especially when it comes to workouts that have them performing in front of others standing around watching versus when I can find some more exclusive floor space) and it would be beneficial to know whether they are holding back or if my expectations are just too high.

I think its a valid point that the graph is just a graph and matters less if you don't get out and do something, but from a logistical standpoint of measuring fitness levels and grading workouts which we in turn use to create more workouts, I think the value of that work capacity chart is being adulterated.


Adam Kruppa wrote …

Good Article, and i'm glad that he didn't even TOUCH power output when running.
This is an insurmountable task with all the factors of friction and bodyweight.

I really think the next level of (relative) power measurement will be surrounded by Body weight ratio's. Just as he mentioned the comparison of little guy doing fran to big guy doing Grace. If you really wanted to compare, take the person's bodyweight into comparison and see how the numbers come out.

Thanks for taking time to submit article Russell.

AJ Kruppa
CrossFit SWFFT


Christopher Bishop wrote …

I think this is where competition or comparing yourself with with others has a downfall. People can get paralysis from analysis and start splitting hairs, or even make excuses why someone is better at XYZ than themselves. Ultimately when I train (crossfit or otherwise) I am looking at improving MYSELF, not beating someone else. They provide some additional motivation granted, but ultimately it's about improving my game, my power output or my technique and efficientcy.

Think about it for a minute, do olympic athletes get medals because their weight:100m sprint ratio is better than the next athlete? No. It's who ever gets their first wins the gold. All any individual athlete can do is to focus on their training and persue constant improvement. How good another athlete is, is completely out of their control.

And finally, if you only compare yourself to others, you can be lazy and complacent when ontop. So no matter your ability, you should always look at improvement.


wrote …

First thing first, you never want to obsess to the point of paralysis. If your over analysis your performance your performance will suffer. Just due to how much time it takes.

Secondly, it is possible to take the work(J) measurement of more complex movements. By making conservative assumptions, you can be sure that you will not be short changing yourself when finding how much work or power you put out during a 5K run. IMO running should be found with Kinetic Energy KE=0.5*m*v^2 (average speed). Elevation changes also need to be taken into account if significant. Attempting to incorporate a friction or wind into the model adds unnecessary complications.

Thirdly, the most useful way to use Work and Power data is to look at it from a distance and to hold constant to a particular standard for the calculations. When you do this you can look at one graph and see over a years worth of data. Quickly and effectively telling you where your weaknesses are and how you have improved.

Conclusion (IMO) I appreciate Russell taking the time to write this article and bring it to the community. But his dismissal of the analytics of Crossfit neglects a very USEFUL tool.


wrote …

I am not interested in measuring power output to keep track of my own progress. I just keep track of my times and body weight changes to get a general idea of my progress.
However, I am competitive. And as it does for many others, competition motivates me to try harder. I get interested in power output when I compare my 6'2" 185 pound frame doing thrusters, versus the 5'8" 185 pound guy next to me.
When I look at my fran time and compare it against his I tend to give myself a little extra "credit" because I moved the weight an extra 6 inches each rep. Shouldn't I get a little credit for moving the same amount of weight an extra 45 feet? And I'm sure he is thinking the same thing every time we do wall balls. 8^)


wrote …

I love the article. The games don't attempt to measure power. They measure exactly what Berger is talking about: time, weight, reps.

I like the concept of graphing fitness and health. However, it seems almost like a thought experiment to me. Is it practical? Are there many benefits? Has this actually been done? I don't spend much time in the forums, so if there is something there please point me in the right direction.


wrote …

Russell, was hoping you would discuss the idea of using power output as a means to judge proper scaling.

Read a newby post - did an as Rx'ed Elizabeth ... in 45 mins. 2 reps per minute is clearly not enough intensity for that WOD, my conjecture is he would have improved his fitness more, and would make faster gains on Liz and other WODs, by scaling to a load that would have allowed a 15 minute or better completion.

HP output for the my last 100% Linda was 40 ft#/s, 70% Linda was 65 ft#/s, and 90% was 55 ft#/s. Those data points are invalid due to the long intervals between events, but for the sake of argument could I assume that I'm getting a better workout at the 70% scaled effort? I don't know if anyone's done the testing to find out.

Seems probable that for any given workout, there's a load that would produce the fastest gains - why wouldn't that be the load that generates the highest HP? Fits the 'intensity is the key variable' concept.

That said, I'm not interested in the concept enough to pursue it. Would rather just Rx the WOD when able.


replied to comment from Paul Eich

Interesting thoughts. I'd say you've already answered your own question with the Elizabeth part. You don't need to know what the ft-lbs/min is of that Elizabeth to know scaling the next one down is probably a good idea.

Your numbers for Linda are among the most interesting applications of power calculation that I've seen. Still, though, I think any conclusion is spurious. Why?

Well, we know that maximizing power is essential to fitness, but it's not the only factor. 100% Linda is possibly the most mentally demanding workout for bigger guys. If you always train at 70%, you'd have a higher average power output, but are you getting all the same adaptations? I'd have to say no. Constant variation means even changing how you approach Linda.

We absolutely don't know for sure that always scaling workouts to maximize horsepower delivers better fitness. In fact, I'd bet just the opposite. Human performance is so complex that any simple rule begs defiance. Linda was programmed by Coach the way it was for a reason. Elite athletes should modify prescriptions with great caution.

Don't hear in this blind following with no testing or experimentation. But I've considered Russell's position and I agree with it. Beyond a couple interesting notations, I'm not convinced that power calculations improve results beyond standard but well formulated CrossFit programming (constantly varied functional movement at high intensity).

In other words, show me a coach programming based on power calculations getting measurably better results than one practicing the art and science of CrossFit workouts with a stopwatch. I haven't seen it, and based on these arguments, I doubt we will.


wrote …

It's funny this article came up, I'm 6'1" 225 lbs and I work as an athletic trainer at a high school (this will appear more relevant as the comment continues). Crossfit has started blossoming in the weight room there with the students and fellow coaches mostly because of the example that myself and a former student (soon to be attending his first cert) have set regarding following the mainsite workouts for close to four years now(no way meant as self-aggrandizing) and even though the newbies are doing scaled versions of workouts they still look to compare times and we as "trainers" try to get them in what we think are appropiate time ranges for the given wod and its desired effect.

As a "bigger" athlete comparatively, I jokingly fall back on the "Well my power output is off the charts compared to yours" anytime they beat me. This article makes me laugh a bit because I think we tend to get lost in the numbers (power output, comparing to other athletes, etc.) sometimes when it comes to the wods and forget about the spirit of just driving each other past as Todd Widman mentions in his latest series "the wall" that all crossfitters will at some point face in their workout. This personal wall is the one we all must scale each and every day and having someone next to you climbing and surmounting that wall makes crossfit the strong emphatic community that it truly is. Anyway I digress, I guess I'll just have to push harder now that my "go-to card" has been removed from the deck.


wrote …

If we are talking about a particular workout, WITHOUT CHANGING ITS PARAMETERS, then an improvement (reduction) in time will also, necessarily, produce an improvement (increase) in power output.

In this sense, saying that a given performance "expresses power" and saying that it "is a really fast time" is essentially the same thing. The only difference is that one (the stopwatch measurement) implies the second (the power output), because power output is a function of the time it takes to move a given load a given distance.

So, as long as the parameters of that particular workout remain the same, then chasing increased power output is indeed a goal. In fact, it is THE goal. Completing the task more quickly than the previous time is the METHOD of achieving that goal.

In fact, Coach himself wrote (in a thread on the board in 2005) that the goal of his workouts was "the maximum expression of power."

HOWEVER, that doesn't necessarily mean that maximum expression of power in an absolute sense is the best path to a broad, general, inclusive fitness, as it excludes all but a few time and modal domains.

In the example of the handstand push-up, the increased balance required in relation to a barbell shoulder press makes a comparison of power output between the two movements an unfair and unenlightening one. There, it is not whether one movement produces more power, but whether you can increase your power output in either or both over time, that matters most.

Also, there are benefits to training both absolute strength (as in heavy deadlifts) and endurance (as in a 10k run) that a singular focus on Olympic lifts can not provide, which is why it pays (for GPP purposes) to train a range of time and modal domains. Here, too, though, increases in absolute strength and decreases in the time required to compelte a long run will, by definition, be increases in power output.

WHERE IT GETS TRICKY is in trying to determine whether one is better off performing a workout as prescribed, even if it takes a long time and therefore leads to a low power output -- or scaling loads, reps and/or duration to produce a faster time and therefore a higher power output.

This article does not offer much in the way of evidence in arguing against the long-term benefits of scaling, whether that be scaling up or scaling down. I'm sure there are many athletes and trainers who would argue that "the art of scaling" is extremely important.


wrote …

"Russell's point is that measuring the average power of CrossFit workouts in ft-lbs/min is unnecessarily precise, and ultimately contributes little to nothing of value beyond just trying to do better at CrossFit workouts."

Sure... but it's fun.



Sam, you are exactly right.

A faster time is indicative of a higher average power output but the inverse is not necessarily true. Power output is the goal, yet measuring it is completely uneccessary for acheiving the outcome- improved fitness.

I would say that scaling, like programming, is part science and art. Should you go lighter and complete the workout faster, or should you go Rx'ed and take as long as you have to? The answer, as i've heard Coach say, is yes.


wrote …

study World-Class Fitness in 100 Words and read it over and over again. greg glassman explains everything in those 100 words. if you summarize it, it says:

#1 - eat paleo foods in zone quantities
#2 - lift heavy weights
#3 - master gymnastic skills
#4 - do some form of "traditional cardio"
#5 - mix weights, gymnastics, and cardio into a workout and time it
#6 - keep workouts short and intense

all six points are great, and points #1, #5, and #6 have been invaluable to my life and my training success (which is not much).

study the early crossfit videos, study the successful athletes at the crossfit games.

i saw videos of chris spealler's wod's prior to the games and i never saw him run long distance, yet he finished first in the long run at the 2009 games. jason khalipa ran prior to the games, but did not perform as well as spealler at the games event. however, khalipa did tremendously well at everything else. the top finishers at the 2009 games finished all of the events except the run in under 20 minutes. i would hypothesize that these athletes have the ability to produce such a high power output that enables them to finish the workout more quickly. so in conclusion, what are these athletes doing that is making them successful?

crossfit: functional movements, at high intensity, with constant variance

in comment #11 you said, "Linda was programmed by Coach the way it was for a reason."
-please explain to me why coach programmed linda the way he did. i'm very intrigued to know why.

in comment #17 you said, "Should you go lighter and complete the workout faster, or should you go Rx'ed and take as long as you have to? The answer, as i've heard Coach say, is yes."
-i like this so much i'm going to write it in training notebook. thanks!


wrote …

This article raises two important questions in my mind.

CrossFit is composed of functional movements, whereby functional movements are "categorically unique in their ability to express power output."

How can we talk about the ability to express power output if we don't at least estimate how much power output that certain movements and/or workouts express?

Secondly, CrossFit defines fitness as work capacity across broad time and modal domains. Correct me if I'm wrong, but it seems that this article suggests that work capacity should not be considered equivalent to power output. Previously I was under the impression that CrossFit defined work according to its common usage in physics, i.e. work = force * distance. Was I mistaken?


replied to comment from Russ Greene

As to point one, we have done sufficient analysis of the power generated in our workouts to conclude that they are high power relative to other workouts of similar duration. We also know that reducing your times and/or increasing your reps or loads increases power. Knowing precisely how much power was actually generated is ultimately irrelevant. Hit the workouts as hard as you can. You will get the same adaptation if do the mathematical calculations or don't.

As to point two, same as point one. Power retains it's essential role; measuring the actual ft-lbs/min adds nothing beyond knowing you need to reduce your times and increase your reps and loads.

Read the description I linked to in my previous comment on artificial precision. What time is it right now? When you answer, does adding the seconds contribute to your daily life? Very rarely. When you say your age, do you include the days? After some point, the increased precision is irrelevant or even misleading (I could expand this dramatically if anyone doesn't understand it after reading the linked explanation).

You really do need to time your workouts and count your reps to optimize fitness. You really don't need to have a precise understanding of how many ft-lbs/min of power you're generating.


wrote …


Thank you for the quick response.

I am still confused, however, as to what is CrossFit's definition of work capacity.

Was I incorrect in taking away from this article that Russell Berger at least considers work capacity not to be equivalent to power output(f*d/t)?


wrote …

Just wondering why this subject was brought up again especially when it was articulated in the "Capacity, Standards, and Sport" article of the Crossfit Journal in June, 2008. Everyone should read that article with this one to have a better understanding of what is important. Also, the article about the top three competitors from the first Crossfit games should be read too.


replied to comment from Tony Budding

Tony, enjoyed your response.

With unlimited time and money I would explore my conjecture about using power output to guide scaling of WODs; until then, I concur it is conjecture only. I initially pursued scaling Linda to be able to do the workout when I was only getting 40 min windows max to get WODs done. It got me thinking about the numbers when I thought of how much intensity I was giving up in a one hour as Rx'ed Linda. Goal now is to get an as Rxed Linda in 35 mins.

"Human performance is so complex that any simple rule begs defiance. " This rings true to my not particularly important sense of CF.

Patrick - Looking at the comments, I would say the responses justify the publication.


Jeff Barnett wrote …

My interpretation of the article does not support that Russell is defining fitness other than "work capacity across broad time and modal domains," with power output as the dependent variable and time, load, and distance as independent variables. I think he's saying that the numerical expression of it is almost irrelevant. I think the two ideas can coexist. It's similar to understanding the idea of an integral, but not being able to integrate any mathematical expression thrown at you. Knowing the theory is 95% of the utility. The rigorous application of the theory is not useless, but pales so much in comparison to the theory itself that one might be better served by seeking a deeper understanding of the theory rather than applying it with a spreadsheet. In my experience, both activities have their place, but I definitely agree the former is much more important.

Good discussion in this thread.


replied to comment from Paul Eich


My point was there are at least two articles (Capacity, Standards, and Sport, June,2008; The Quest to Measure Fitness, July,2008) that already cover the irrelevance of average power output (horsepower, HP) when it comes to training and real world applications. On top of that there are many articles that imply the irrelevancy of the HP measurement. The HP measurement is retrospective in that it shows what happened and doesn't predict what will happen. The force measurement of a 1RM is a better indicator of performance than horsepower.

This is purely conjecture at best, but the only way I can see to utilize the HP measurement proactively would be to do the workload utilizing different rep schemes and compare the results. The "Fooling around with Fran" article covers this. Then the person could see where the breakdown in their efforts are and target those areas of the WOD accordingly. Do they start off strong and lose steam towards the end? Are they weak/strong through the middle? Or are they strong finishers?

OR they could take a video camera and analyze the movements frame by frame like the endurance guys do and get a breakdown of what really needs work. Is their concentric phase to slow? Are they taking to long on the transition from eccentric to concentric? Are they lowering the load to slowly? Is it the squat or the press of the thruster that needs work? What about the pull-up are they coming to far forward in the kip? Are they losing it at the top/bottom of the pull-up?

The thing is none of this really matters to the average Crossfitter. They are going to be better off just doing the WOD at high intensity and charting times than looking for ways to shave off a few seconds. Then once they hit their wall and aren't improving do they start analyzing and look for the weak spots that need improvement.


I'm interested in looking at power out for the sake of scaling also. In particular, I just started playing around with Diane. In this instance, I played around with dropping weight instead of decreasing the amount of reps each round. The goal was to maintain speed through out the deadlift portion. In this instance both my workload and power increased. Granted there are many flaws in this example, but it got me thinking. Did Glassman break workloads into 21-15-9 as a matter of convenience? Does it make sense more sense incorporate WODS that keep reps the same, while decreasing weight? I'm planning on doing some more experiments with "drop-sets" using Wall-Balls and looking at power and workload. Should be fun.

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