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Most fit athletes

  1. Jul 30, 2014 #1
    I'm curious which athletes can produce the most work? I watched a decent amount of the CrossFit Games and was wondering if those guys are doing more work than an elite runner, cyclist, or rower. The crossfit slogan is "Fittest on Earth," but I'm not so sure yet. They can do crazy workouts and are very impressive. Although I think the fittest should be able to produce the most work. So who can do the most work????

    Who would win in an all out work competition? For 1, 5 10, 20, 30, or 60 minutes?

    Would it be possible for a weight lifter to produce more work than these endurance athletes or sprinters? Even over shorter durations like 1-10 minutes? If so how would they compare at 30-60 minutes?

    One crossfit competition was doing a clean and jerk at 135 ibs 60 times and one of the guys did it under 5 minutes. Assuming the bar moves 2 meters from the ground position to the overhead position. , this athlete is about 5'7" and does it 30 times in about a minute

    my estimate is: joules= (61kg*9.8m/s^2)*(2m*60reps)= roughly 72,000J in 5 minutes or 36,000 for one minute

    how long would it take other elite athletes to do the same work??? Would runners use the same equation? I'm pretty sure that wouldn't work. This is where I could use some help. How far would a runner have to run to produce that 36,000 and 72,000 joules? If their mass was 50kg, 60kg, 70kg, 80kg? Lets assume they run around a track with no wind, or for cyclist they use a stationary bike, rower, or even treadmill.

    What are your opinions about which athletes or exercises do the most work???

    Thanks for your time

    Last edited by a moderator: Sep 25, 2014
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  3. Jul 30, 2014 #2


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    Here some info on cyclists (bottom of page):
    http://www.aerovelo.com/projects/helicopter/tech-info/ [Broken]

    There should be similar data for rowers. Runners are rather different. I suspect cyclist and rowers can produce more power.
    Last edited by a moderator: May 6, 2017
  4. Jul 30, 2014 #3
    http://www.cbsnews.com/news/are-world-cup-players-the-fittest-athletes/ middle of the page

    "How many calories do athletes burn?

    Here are some of the sports disciplines in which athletes burn the most calories per hour. The following numbers are based on a 175 pound man performing at highly competitive speeds, according to rough estimates provided by English:

    Cross-country skiing -- 1.500 calories per hour

    Running -- 1,400 calories per hour

    Cycling -- 1,100 calories per hour

    Competitive soccer -- 800-1,000 calories per hour

    Swimming -- 800 calories per hour

    Race walking -- 700 calories per hour"

    Skiing: That would put the skier at over 400,000 joules during 5 minutes. Is this correct? I have him at 1,500 kCal per hour. And 5 minutes at that pace would be 102.5kCal.
    4184 Joules= 1kCal. 102kcal*4184= 428,860 J

    Cyclying:http://www.aerovelo.com/wp-content/uploads/2012/03/athletepower.jpg [Broken]
    Here the cyclist, I rounded about 400 to 350 watts for five minutes is getting over 105,000 joules in five minutes.
    Joules= Watts * time (s) = 400W*300s= 120,000 Joules

    Running: I know about 110-120 kcalories is a standard estimate for energy used to run a mile. And running a five minute mile is not even elite. That would produce over 500,000 joules.
    120kcal*4184= 502080 Joules

    Either way they all beat the crossfit dude. But is 400,000 -500,000 joules correct for five minutes of high intensity????
    Last edited by a moderator: May 6, 2017
  5. Jul 30, 2014 #4


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    Don't confuse "calories burned" with "work done". Much of the burned energy goes into heat. The aerovelo link is the usefull power output measured at the pedals.
    Last edited by a moderator: May 6, 2017
  6. Jul 30, 2014 #5


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    I'm sorry but polls are not allowed in the physics areas of the forum, only the general discussion area. I've closed the poll, but the thread is free to remain open.
  7. Jul 30, 2014 #6


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    This guy, C Johnson, Theoretical Physicist, Physics Degree from Univ of Chicago, gives a babble about the Thermal Efficiency of the Human Being on this page of the site.

  8. Jul 30, 2014 #7


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    There's more than just the athelete involved. Bicycles are very efficient at converting the energy supplied by the rider into energy to propel the bike at speed where the net power output would equal the speed times the drag components (aerodynamic drag, rolling resistance, ...). This is why bicyclists and a bicycle like setup was choosen for human power flight aircraft such as the Gossamer Albatross.
  9. Jul 31, 2014 #8
    What if I only wanted to focus on the work done by the athlete? How would I go about calculating that or estimating it more accurately?
  10. Jul 31, 2014 #9
    Sorry I do not know the terminology well enough. I did take two physics classes in college and have a exercise and sports science degree. Maybe I should find an exercise science forum. I'm trying to figure out how to do the most work during certain exercises and I want to determine how well a certain activity would measure fitness. Which I'm thinking about defining more as the ability to do work, not so much power or performance.

    Example, two runners are racing 500 meters: The first runner runs a second faster, but the second runner weighs 10 kgs more (for this example lets assume they both have the same wind resistance and there is no drafting). The lighter runner wins the race, but I would argue the second runner is more fit because he or she does more work over both the same distance and duration.

    Same thing with the bikes or other exercises. I don't really care about the speed of the bike, canoe, or person. I want to find out the work they do in trying to move the object or themselves. Same thing with lifting, a taller person is going to lift an object farther distances and will do more work as a result.

    In my eyes, if you are lighter or have a lighter object, you should have to move it farther/faster than a heavier athlete or object to have equal fitness.
    Last edited: Jul 31, 2014
  11. Jul 31, 2014 #10


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    Last edited by a moderator: May 6, 2017
  12. Jul 31, 2014 #11
    I want to compare the power of different exercises over the same duration. I don't care about the energy lost from the body as heat. I only want to measure the mechanical energy produced by a human body to perform the exercise.

    For five minutes of activity: A elite crossfit athlete can produce about 240 watts over five minutes. From my calculation above of 72,000 joules in five minutes. The elite cyclist in getting between 350-400 watts in the same duration. So hands down the cyclist wins the power competition.

    Does anyone know how running, rowing, or skiing compares? Or if any other activities would compete?

    I did 165 watts rowing (and 80 watts lifting) in five minutes at the gym yesterday. I almost never row, maybe once or twice a year on average at hotel gyms. So I think elite rowers could do pretty well.

    How can I calculate running power? Would a treadmill be a good estimate?
  13. Jul 31, 2014 #12


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    What is running power to you? The power to overcome air resistance? The power to periodically lift the bodies center of mass? The power to accelerate the body segments?
  14. Jul 31, 2014 #13
    The power needed to move the runner over the distance. I realize wind and other things affect the calculations. I would include air resistance and all movements that aid the running forward. Any upward lift or side to side movements I would consider wasted energy. Of course on a really windy day more power would be needed. But running around a track maybe it would balance out more, with the wind aiding and resisting depending on the direction. Or even better a treadmill inside a gym. So a estimate would be fine.

    Can I set up a problem like: a runners with a mass of 70 kgs runs 1600 meters in five minutes indoors, in watts how much power did the runner produce?

    What other factors would I need in this scenario? Can I ignore the air resistance or is there a standard variable to use?

    Thanks for your time
  15. Jul 31, 2014 #14


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    Lifting the legs upward does aid the running forward. Included or not?
  16. Jul 31, 2014 #15
    In my Definition "fit" relates to someones (thing) ability to do a job. I highly admire the crossfit people - because I appreciate their commitment and and accomplishment in doing the variety of tasks. Similar to many people seeing the decathlon as the ultimate track AND field competition.
    However none of these really relate to to a relatively cold interpretation of who does the most work ( technically speaking) over a period of time.
    So to me these are different things - like comparing 2 or more different types of race cars - 1) Highly biased, 2) What is the point.
    IMO people take part in sport because it (that specific sport) appeals to them - and they want to be the best. Not many athletes say, "because I won this I am the best athlete ever" however decathletes ( traditional) and many crossfit ( today) could lay reasonable claim to this. But measuring the work they do is not how they measure themselves.
    Lastly - each type of athlete develops into their own sport, their body adapts to surviving, not doing the most work, but actually doing the least. The Calorie counts per-hour are typically for specialists - not generalists. Define fit to me - the ability to do 10 challenging things is more impressive than doing one.
  17. Jul 31, 2014 #16
    Included! But if the runner jumped for some reason during the run, don't include that.
  18. Jul 31, 2014 #17


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    Then you have to estimate segment inertia and integrate the accelerating power. To be comparable to cycling/row, you need to do the same thing there, not just consider pedal/pull power.
  19. Jul 31, 2014 #18
    I have been looking at crossfits forums as well (which is blocked so I can't join it) but they do care about measuring work and power. Here are two links I saved

    I'm with you and I agree. I think doing 10 challenging things is awesome, and those crossfit guys are amazing. I just don't think their competitions reward the most fit athlete. I think it is more of a strongman competition for longer durations. So I started looking to find the activities that would produce the most power.

    Every event is going to benefit those who are naturally built for certain movements. So being the best or most fit is more an attribute to genetics than anything else. I think the crossfit athletes are too bulky to be the fittest and rewarded for having short levers, arms and legs. I think football players would destroy them if they weren't paid millions of dollars to play football. Decathletes are probably among the most fit, but they require a lot of skillful movements also. Which makes crossfit cool because (besides the olympic lifts) most of the exercises rely on strength, power, and fitness.
    Last edited: Jul 31, 2014
  20. Jul 31, 2014 #19
    That would require a lab. Do you have any equations or ideas to get the best simplifications/estimates to account for that?

    On a stationary bike or rower, does the machine measure the power transferred to the pedal or pulling mechanism? If you were curling a dumbbell at the same time it wouldn't affect or contribute to the row or cycle power.

    I get the impression that you are trying to tell me that there isn't a simple answer to my question.

    What is the best or most accurate way to estimate power during running without a lab?
    Last edited: Jul 31, 2014
  21. Jul 31, 2014 #20


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