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Carl Lewis 30ft Long Jump


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  • #61
    My recollection is that Carl Lewis run up was about 170'/52m. I don't remember any of his contemporaries had a longer run up.


    • #62
      Originally posted by Pierre-Jean
      If you don't trust Lewis 6.02, then use 6.04 (in 1983, worth 6.47-6.48) or 6.06 (in 1981, worth 6.49-4.50). Phillip's next best ever is 6.53, do you doubt his 6.47?

      The difference between Tomlinson and Lewis is that Lewis requires more distance to reach max speed (Tomlinson prolly 50m, Lewis 70m).

      Your reasoning should apply to all jumpers, they all use shorter runs up than 50m, hence should all take longer runs up to reach max speed. Again, the problem is to transfer your sprint into a jump, hence all the jumpers have an approach speed during run-up fractionnally slower than their max speed during sprints.
      i have little faith in early '80s clockings without RT quotes/equipment

      he was a slow starter & also likely reaction, so good chance he tried to catch a flyer in those american meets knowing little chance of being called back by starter who knew who the big draw was

      in europe races, he never looked like a mid-6.4 guy in his 100m races

      dwight's 6.47i i have perfect faith in - RT equipment at hand to call a flyer - it obviously wasn't

      as for run-ups - sure, they shoud try 60 - 70m ones, but as i said, you're only going to have enough energy to do 2 or 3 jumps out of 6 if you're running flat-out 60m

      likelihood is you may not not get in 1 valid jump out of 1st 3 attempts in a championship with this hit & miss approach - so basis of risk/reward, not a viable proposition there as you may not get a valid jump in initial 3 attempts

      your also only likely to have 2 attempts out of initial 3 ( 1st & 3rd attempts ) as fullout sprinting for 60m isn't likely to let you recover for attempt 2

      cutting run-up to 50m means majority have sub-max speed at take-off, but better control & likely to get a valid jump in, but not ultimate potential jump - the physics shows speed is better than angle

      i've seen enough of his jumps & got bored with his run-up, which for last 20m looked liked he was cruising the 130 - 150m section of a 200 - not attacking the board with the ferocity of like a lebedeva

      he had 0.83s speed & wasted it by never trying 60 - 70m run-ups

      time to attempt it was not a championship, but a gp meet with 6 attempts guaranteed & knowing he was only going to put in 2 or 3 attempts, inform promoter this was going to be a hit & miss affair trying to see if coud "nail" an angle & be behind the board with one of his 2 or 3 attempts

      bottom line -

      - standard run up, he had 50%+ chance of a 8.50+ & obviously a likely win

      - 60m+ run-up maybe gave him a 5 - 10% chance of a 9.00m jump in a meet - trying a dozen meets between '82 - '92, woud give him mathematically a

      ~ 45 - 70% probability of a 9.00m jump


      • #63
        last part is interesting ( to me's anyways ! )

        say he did try a 60 - 70m run exclusively in a meet & did it 12 times in his career when he had exceptional speed ( '81 - '93 ) - i e 1 meet/year

        you can't say he had no chance of "nailing" a jump ( he was of unique calibre ), just very little probability

        trying different probabilities of nailing it in 1 meet & seeing what overall probability is of doing it at least once during 12 meets

        1% -> 1 - 0.99^12 = 11.3%
        2% -> 1 - 0.98^12 = 21.5%
        3% -> 1 - 0.97^12 = 30.6%
        4% -> 1 - 0.96^12 = 38.7%
        5% -> 1 - 0.95^12 = 45.9%
        6% -> 1 - 0.94^12 = 52.4%

        so, if he had a 6% chance of 9.00m at any 1 meet with a 60 - 70m run-up, then 12 meets in a career attempting such, means probability wouda been in his favor of jumping it


        • #64
          Originally posted by eldrick
          as for indoor pbs, people have expressed scepticism at 6.02i - he never ever looked that fast for 60m

          besides, that 6.46 split had a +1.2 wind overall for 100m - jrm has 60m calc ( he says if wind for 100m race is used for 60m split there is little more than 0.01s error ) -> ~ 6.50s basic ( rome split is better at 6.49 basic )
          I don't see how Rome split 6.50 becomes 6.49 basic.
          However, his reaction time was terrible 0.196. This gives 6.30 without reaction time and 6.40 "basic" with perfect reaction time. With an average reaction time, he was able to run mid 6.4, which ties with his 6.02, 6.04, 6.06, 6.07 60 yards times, all worth about 6.45-6.50.
          If he he was allowed to do flying starts in those 4 indoors races, he was allwoed to do so outdoors? I don't follow your logic.

          Carl Lewis run-up was 21 steps in Tokyo'91, but speed is recorded btw 1 and 11m to the board, so he is in the zone after 18 steps i guess. However, the is a reduction of speed on the 1 to 0m to the board, in ordert to prepare the jump and transfer horizontal speed into vertical speed. That's why your reasoning is false regarding Lewis using his 12m/s top speed into a jump. Body positions are different in sprinting and run-up, same thing applies for Drechsler.


          • #65
            jrm has a 60m function in the drop-down menu of his 100m calc

            try it out - 6.50 with +1.0 -> 6.523 basic ( i put in something wrong to get 6.49 basic )

            take off 0.05s for poor rt & his likely at best 0.14s & you get 6.47, which i agree is same as dwight's

            as for his top speed, i already mentioned 0.83s is likely to dip at take-off to 0.84 or 0.85s, but this is still hugely quicker than 0.89s speed ( 11.2 ) & he even dipped from there to 0.904s speed as you quote

            Carl LEWIS 8.91m
            11.23 / 11.26 / 11.06 / 9.72 / 3.22
            he dipped from 11.23 from 6 - 11m out to 11.06 at take-off -> ~ 1.5% reduction

            apply that to 0.83 & you still have 0.84 - 0.85 with slowing at take-off, which is still helluva lot quicker than 0.904 speed

            all it comes down to is what angle he gets with 0.84 - 0.85 speed - if he coud manage 11.5 degrees ( just over 1/2 of usual angle ), he'd get 9.00 with it

            put it in yourself


            poster on page 1 says we shoud use 1.16m for c o m

            I think the centre of mass of 1.25 is a little bit to much. I thought centre of mass was about 0.6180 times height. so in Lewis case around 1.16
            ( you can try the data on page 1 as a test for it - just use pythagoras on 2 speed components ( angle is sometimes out by 0.1 degree though when you do arctan - but this is small error in measurements as you'd expect ) )

            try 0.84 or 0.85 speed with that & see what angle is needed for 9.00

            coud he have done 11.5 degrees ?

            i think it's feasible


            • #66
              To re-raise an issue about COM: Should we really use the COM at stand-still?
              To me it seems to make more sense to use COM at the time the take-off foot
              looses contact with the ground. (This will depend on exactly how and when
              speeds are measured, and whether the sole-contact-to-toe-contact change
              increases or decreases vertical speed.) I made a (very) approximate measurement on myself (also 6'2''-6'3''), and saw roughly a 10 cm increase, which puts us
              back at roughly 1.26.

              Admittedly, the effect will likely be limited, but one or two extra decimeter
              lengthwise seem plausible to me. (The projectile applet, unfortunately, crashes my browser.)

              Similarly, arm-movements may possibly raise the COM a few additional