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Highest force is at ZERO speed ?

  1. Apr 17, 2009 #1
    highest force is at ZERO speed ???

    Hi all,

    I say you can use more force on a non movable object than an object that is you’re RM, which is the maximum weight you can lift one time 1RM. Who is right, and is there an equation to prove this.

    The "highest force" as I suggested is at ZERO speed. That is simply indicative that if you allow something to move, the amount of force you can generate against it will decline, or you will have to attempt to accelerate it (if it has mass that is).

    The 1RM of a movement will produce slightly less force than the maximal voluntary isometric contraction, as the 1RM is dynamic rather than static or non movable.

    Example, an athlete's max squat 200kg, at 201kg, the athlete would not be able to move the bar; however, if he applied max effort the maximal voluntary isometric contraction force would be slightly greater than the force produced during the successful 1RM lift.

  2. jcsd
  3. Apr 18, 2009 #2
    Re: highest force is at ZERO speed ???

    Hi Wayne,

    Good question.
    Strictly speaking from a mechanics approach the definition of force is: force=mass x acceleration
    The force obtained can then be multiplied by a coefficient of friction. When an object is at rest it has a static friction, when it is in motion, it has a kinetic friction (which is generally smaller than static friction). In other words, as long as the athlete does not overcome the (force of static friction + force), the weight will not move. Once the weight is in motion, the force of kinetic friction(instead of static friction) is added to the force and the weight will move more freely. So yes, as long as the weight is not in motion, the force required to move it is greater.

    However, if you calculate work, lifting the weight as far as you can will prove to be far more beneficial, as you will multiply the force by the distance. Anyways this is pretty simplified but I hope it helps. Train safely!
  4. Apr 18, 2009 #3
    Re: highest force is at ZERO speed ???

    Hi and thx,

    See what you are saying there, it would take 200.5kg to move the weight, but only 200kg to keep it moving.

    Could we forget about multiplying the force by the distance for now.

    However, if my max lift was 200kg on a dynamic moving object, but if I applied my max force/strength on a non moving static object, in my opinion my max force/strength would be more, not much more, but if we were on a force place I could register say ??? 3kg more than I did on the dynamic moving object, would you agree ???

    Its sort of the same as if I crashed into a car with my car, there would be a lot of damage, however if the car that I crashed into was bolted down, there would be more damage to both cars

    Hope I am explaining right.

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