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    A Pedestal Design for the Total Gym

    Contents

    Project Overview ........................................................................................................................................... 3

    Bill of Materials, Tools and Suggestions ....................................................................................................... 5

    Pedestal Assembly and Detail Drawings ....................................................................................................... 6

    General Views of the Pedestal .................................................................................................................. 6

    View of the Pedestal and the Total Gym showing Assembly Details ........................................................ 7

    Dimensions of the Base............................................................................................................................. 8

    Dimensions of the Angled Support ........................................................................................................... 9

    Dimensions of the Top ............................................................................................................................ 10

    Dimensions of the Upright ...................................................................................................................... 11

    Dimensions of the U-Bolt ........................................................................................................................ 12

    Some Close-Up Views of the 2 7/8 x 4 Pedestal and the Platform Weight Bar........................................ 13

    Static Resistance Provided by the Pedestals Height.................................................................................. 15Height & Incline Comparison of the Total Gym 1000 Series and the Total Gym on the Pedestal .......... 15

    Graph of the Static Resistance Presented to the User as % of Platform Load and Angle ...................... 16

    Examples of Static Resistance vs Platform Load and Angle .................................................................... 16

    Calculating the Force and Power Required to do the Prone Push-Down Exercise ..................................... 17

    Details of an Example Prone Push-Down ................................................................................................ 17

    Diagram of the Platform Forces .............................................................................................................. 17

    Equations for Force and Power vs. Time for the Example Prone Push-Down Exercise .......................... 18

    Calculating the Force and Power vs Time from the Platforms Acceleration and Velocity 19

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    Project Overview

    The Total Gym 1000 series is a terrific piece of exercise equipment for strengthening the muscles used inthe canoe and kayak paddling motion. It allows a large variety of arm motions and requires engaging the

    torso and back while using the arms. Some people using the Total Gym for paddling-related exercises

    find that the exercise resistance available in the product is too small. This project provides details of a

    pedestal that increases the exercise resistance. The exercise resistance comes from the angle of the

    platform and the weight on the platform. Increasing the exercise resistance can be done either by

    increasing the platforms angle so that a larger percent of the users weight is lifted or by adding weight

    to the platform via attachment of a bar at the bottom edge of the platform for the addition of barbellplates or by doing both.

    Here are drawings and photos of a pedestal I made to increase the platforms angle and with it the

    exercise resistance. Along with the increased height the pedestal also improves the lateral stability by

    increasing the width of the base by 68% (from 16 to 27). I have used this pedestal for about three

    years and I found it is stable and rigid. Im quite happy with it. The motivation for increasing the

    platforms angle via this pedestal is an alternative to the method used by Mr. Marc Gillespie (principal of

    Forge Racing). Marc has the upper end of his Total Gym attached to a steel pole in his basement. Thepole is a structural support of the house, is about 4 in diameter and is commonly used in house

    construction in this area. My house also has such support poles but there are none in a location

    convenient for placing the Total Gym.

    The finished pedestal looks like this:

    http://www.forgeracing.org/http://www.forgeracing.org/http://www.forgeracing.org/
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    You are responsible for safety while using the Total Gym and any modifications you make to it. If you

    increase the angle of the platform by simply putting the vertical support on top of something such as a

    box then the vertical support wont be vertical and the Total Gym will be unstableand unreliable. Dont

    use the Total Gym in an unstable or unreliable condition. Be aware that increasing the angle of the

    platform causes increased load in the hand grips, cables, pulleys and fasteners. You are responsible fordetermining that your hand grips, cables, pulleys and fasteners are capable of handling the increased

    load before you decide to use them.

    The following pages show the materials, tools and parts used for making a pedestal from 4 x 4

    dimensional lumber. What the lumber yards call 4 x 4 dimensional lumber is actually 3 x 3 when

    it arrives in the hands of us users. You will see 3 x 3 on all the drawings. The pedestal shown in the

    photo is the one I have used for several years and it is made from a large pallets stringer which is 27/8

    x 4.In this paper Ive taken its design and adapted it to the more common 4 x 4dimensional lumbersize. In case youre wondering, I have not used 4 x 4 dimensional lumber and these drawings to build a

    pedestal. The pedestal I made is from 2 7/8 x 4 lumber. If you find an error, missing dimension or have

    a suggestion about this project please contact me.

    A person could get the same static resistance increase by adding weight to the platform instead of

    increasing the platform angle. Adding about 54% of your body weight to the platform will be statically

    equivalent to increasing the platform angle the amount this pedestal affords. I found the standard Total

    Gym is too unstable side-to-side when set to its maximum angle and the platform is moved aggressively.

    Before I added more weight I wanted to add side-to-side stability. The platform added stability and

    static resistance. Adding weight to the platform is a good idea only if the system is stable. The additional

    weight requires that you apply additional force to accelerate it. After developing the pedestal I added a

    bar and weights to the platform in the same way others have done. A detailed photo of the bar

    attachment is at the end of this document.

    Youre welcome to use this design for any non-commercial purpose. If you make one, you have the

    responsibility for the quality and care with which you make it, the quality and care with which you

    attach the Total Gym to it and the suitability of the whole system for any use you put it to.

    In the pages after the design details there is an analysis of force and power involved in the prone push-

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    Bill of Materials, Tools and SuggestionsBill of Materials

    4 x 4 x 10 Dimensional Lumber, Qty 1.............. (9 4 is needed, can be made from one 8 and one 4)

    2U-bolts, Qty 2 ............................................... (for fastening the vertical uprights base to the pedestal)

    x 3 Hex Head Lag Screws, Qty 7 ............................................. (for fastening the pedestal together)

    I.D. x O.D. Flat Washers, Qty 11................................... (7 for the Lag Screws and 4 for the U-Bolts)

    1 x 1 Right Angle Braces, Qty 2.................. (for positioning the lower end of the diagonal support)

    1 Wood Screws, Qty 6.......................................... (for fastening the Right Angle Braces to the pedestal)

    Wood Glue, Qty A/R ..................................................... (as required, for fastening the pedestal together)

    Tools

    Tape Measure

    Carpenters Square

    1/8 Drill Bit .................................................................................. (pilot holes for the x 3 lag screws)

    Drill Bit ............................................................................ (clearance holes for the x 3 lag screws)

    1 Auger Drill Bit ...................... (clearance holes for the 7/16 socket used on the lag screws and U-bolts)

    Saw ..................... (Hand, Circular, Table or Bandwhatever suits you. I used a hand-held circular saw.)

    Drill ..... (I used a battery powered portable for the1/8 and drills and a ratchet brace for the 1 drill)

    7/16 Socket and Wrench......................................................... (tightening the lag screws and the U-bolts)

    Protractor .................................................................................................................................... (optional)

    Suggestions

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 6

    Pedestal Assembly and Detail Drawings

    General Views of the Pedestal

    FRONT BACK

    Back To Table of Contents

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 7

    View of the Pedestal and the Total Gym showing Assembly Details

    Back To Table of Contents

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 8

    Dimensions of the Base

    Back To Table of Contents

    Section A View of

    Clearance Holes

    Diameter

    Diameter 1

    A

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 9

    Dimensions of the Angled Support

    Back To Table of Contents

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 10

    Dimensions of the Top

    Back To Table of Contents

    Section B View of

    Clearance Holes

    Diameter

    Diameter 1

    Section A View of

    Clearance Holes

    Diameter

    Diameter 1

    A

    B

    Check your U-bolt

    center-to-center

    distance before

    drilling these holes. I

    notice the bolt

    distance varies about

    1/8

    These holes are for the U-Bolts.

    See the notes on the U-Bolt

    dimensions page before drilling.

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 11

    Dimensions of the Upright

    Back To Table of Contents

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 12

    Dimensions of the U-Bolt

    Oddly enough, a 2 U-Bolt is intended to be used on a 1 pipe!

    If your U-Bolt comes with a flat plate, just remove it. It doesnt get used.

    Height of the bolt varies with manufacturer.

    Typical height is 3" or 3 ".

    The drawing for the TOP gives of thread

    for the nut if you have a 3 bolt. And the bolt

    will be clamping 1 of wood.

    If you have a 3 bolt you might want to

    clamp 1 of wood by shortening the depth

    of the four 1 diameter holes to 2.

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 13

    Some Close-Up Views of the 2 7/8 x 4 Pedestal and the Platform Weight Bar

    The three attachment points of the Total

    Gyms vertical upright to the Pedestal -Two U-bolts at the base. One lag screw

    through an existing hole in the Total Gyms

    vertical upright. Use the hole located about

    13 up from the base of the Total Gym.

    Bottom view of the recessed U-bolts

    fasteners

    Attachment of the diagonal

    support to the pedestal

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 14

    Bottom View of Platform Showing Attachment

    of Additional Bar for Barbell Plates

    Back View of Pedestal

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 15

    Static Resistance Provided by the PedestalsHeight

    The resistance of the Total Gym, like all free weights, has two components the static resistance and the dynamic resistance.

    Static ResistanceThe static resistance is the force required to hold the platform load in any position. The static resistance is determined by the

    platform load and the platform angle.

    Dynamic ResistanceThe dynamic resistance is the force required to accelerate the platform load. The dynamic resistance is determined by the total

    moving mass and the acceleration of that mass caused by the users applied force.

    The static resistance is the minimum force the user will experience; the dynamic resistance is determined by the users effort ; and the sum

    of them is the total resistance experienced by the user.

    Height & Incline Comparison of the Total Gym 1000 Series and the Total Gym on the Pedestal

    Total Gym 1000 Series Total Gym on Pedestal

    Platforms Guide RailLength 89 Platforms Guide RailLength 89

    Guide Rails Lowest Height 10 1/4 Rails Incline: 6.6 Guide Rails Lowest Height 42 Rails Incline: 28.2

    Guide Rails Highest Height 37 7/8 Rails Incline: 25.2 Guide Rails Highest Height 58 1/4 Rails Incline: 40.9

    Photos in appendix A were made while gathering these dimensions.

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 16

    Graph of the Static Resistance Presented to the User as % of Platform Load and Angle

    Examples of Static Resistance vs Platform Load and Angle

    Users Weight (Lbs) Additional Weight (Lbs) Total Weight (Lbs) Platform Angle ()

    Static Resistance (Lbs)

    =Sin(Platform Angle) x Total Weight

    160 0 160 38.1 99

    160 40 200 38.1 123

    185 0 185 40.9 121

    185 50 235 40.9 154

    Back To Table of Contents

    0%

    10%

    20%

    30%

    40%

    50%

    60%

    70%

    80%

    90%

    100%

    0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

    %ofPlatformL

    oadPresentedtoUserasStaticRe

    sistance

    Platform Angle, Degrees

    Static Resistance Presented to User as % of Platform Load and Platform Angle

    Resistance as % of Platform Load= Sin(Angle)*100%

    OnPedestal:H

    ighest

    OnPedestal:L

    owest

    Standard:Highe

    st

    Standard:Lowest

    Use of the pedestal increases the maximum static resistance by

    54%. Raising it from the standards maximum at 43% of

    platform load to the w/pedestals maximum at 65% of the

    platform load.

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 17

    Calculating the Force and Power Required to do the Prone Push-Down ExerciseThe motion of the prone push-down exercise is very similar to the top hand motion of the canoe stroke. That similarity makes it great for training. It is

    possible to calculate how much force and how much power are used to do this exercise. The calculated power can be thought of as the top hands

    potential for propelling a canoe. Many people advocate the top hands

    power to be critical in developing canoe speed. That thought leads to

    asking: At a given speed of a tandem canoe, what percentage of the

    required per-person power is equal to the top hands power potential? Inthe next few pages Ill develop an answer to that question and the

    question of force needed to do this exercise.

    For starting out, here is a list of the information I know:

    Details of an Example Prone Push-Down

    Diagram of the Platform Forces

    Here is a simple diagram of the platform and the forces acting on it:

    Angle of Platform 38.1 degrees

    Users Weight 160.0 lbs

    Added Platform Weight 40.0 lbs

    Platform Travel (observation) 18.5 inchesPlatform Starting Speed (at the bottom) 0.0 in/s

    Platform Ending Speed (at the top) 0.0 in/s

    Travel Time, bottom to top (observation) 0.5 Seconds

    Acceleration due to Gravity 386.4 in/s2

    1) Push Down

    2) Platform Moves Up

    Prone Push-Down Exercise on a Total Gym with Pedestal and

    Additional Platform Weight

    Total Platform Mass x Acceleration due to Gravity = Force of Gravity

    MTotalx g =Fgravity

    38.1

    Applied Force as Function of Time = F(t)

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 18

    Equations for Force and Power vs. Time for the Example Prone Push-Down Exercise

    I want to know what the applied force is as a function of time. There are only two forces tha t act along the platforms line of travel. Those are the

    applied force and a portion of the force of gravity. Notice that they act in opposite directions, so we can call the direction of the applied force

    positiveand the direction of the portion of the gravity force that acts along the platforms line of travelnegative. Let Mtotalrepresent the total

    mass on the platform and g represent the vertical acceleration due to gravity. The portion of the force of gravity that is acting along the platforms

    line of travel is equal to Cosine(90-38.1) x Mtotalx g. Since the cosine and the sine are 90apart we can write that as sin(38.1) x Mtotalx g. Sir Isaac

    Newton pointed out that the sum of all the forces acting on a body and along any one line of action equals the time rate of change of the bodysmomentum (momentum equals mass x velocity) along that line of action. Thats the long way of saying the familiarand simplified F = ma. Putting

    all that together gets us an equation for the force that the user applies to the platform as a function of time and the acceleration that it gives to the

    platform as a function of time:

    We can also calculate the power as a function of time by knowing that mechanical power is force multiplied by velocity.

    Since we want to know the force as a function of time, we must figure out the acceleration as a function of time. And since we want to know the

    power as a function of time, we must know the velocity as a function of time. Fortunately for us the acceleration is related to the velocity:

    acceleration is the time rate of change of velocity. So if we know or can estimate the velocity as a function of time, then we can know the force and

    power as a function of time. Instead of measuring the velocity vs. time, I will estimate it based on experience from doing the exercise. When doing

    this exercise it is noticeable that the platform velocity increases to a peak just before the top. Then it slows quickly to a stop at the top. The force is

    large and increasing at the start of the motion. Then it quickly drops to what feels like zero just before the top. Then it quickly rises again at the top ofthe travel. From those observations I believe the platforms velocity vs. time is close to a skewed parabola: a nice smooth velocity vs. time curve that

    starts at zero going slowly up to a peak then going quickly back to zero. We can use that observation and the other facts we know to calculate an

    estimate of the force vs. time and the power vs. time.

    *This is the familiar F=maand the Greek

    letter sigma,, means sum of the+

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 19

    Calculating the Force and Power vs. Time from the PlatformsAcceleration and Velocity

    0.0

    10.0

    20.0

    30.040.0

    50.0

    60.0

    70.0

    0.0 0.1 0.2 0.3 0.4 0.5Velocity(inches/second)

    Time (Seconds)

    Velocity Along Rail vs Time

    0.0

    5.0

    10.0

    15.0

    20.0

    0.0 0.1 0.2 0.3 0.4 0.5Displacement(in

    ches)

    Time (Seconds)

    Displacement Along Rail vs Time

    -900.0-750.0-600.0-450.0-300.0-150.0

    0.0150.0300.0

    0.0 0.1 0.2 0.3 0.4 0.5Acceleration(inches/second^2)

    Time (Seconds)

    Acceleration Along Rail vs Time

    Based on experience from doing the prone

    push-down exercise this is an estimate of the

    velocity vs. time: a skewed parabola.

    v(t) = -3552t3+1776t

    2

    This displacement vs. time is the integral of the

    velocity vs. time equation and it fits the known

    fact of 18.5 travel in 0.5 seconds.

    This acceleration vs. time is the derivative of the

    velocity vs. time equation.a(t) = -10656t

    2+3552t

    -100.0-50.0

    0.050.0

    100.0150.0

    200.0250.0300.0

    0.0 0.1 0.2 0.3 0.4 0.5

    Force(Lbs)

    Time (Seconds)

    Force Applied to Platform vs Time

    0.0

    0.5

    1.0

    1.5

    2.0

    0.0 0.1 0.2 0.3 0.4 0.5

    Power(H.P.)

    Time (Seconds)

    Power Applied to Platform vs

    Time

    AverageTwo Arm Power

    AverageOne Arm Power

    The average one-arm

    power is 0.4 HP

    The peak force is 275 Lbs

    which is 2.2x the static

    force of 123 Lbs.

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 20

    Power Required Per-Person in Tandem Marathon Canoe Paddling

    How much power does it take to paddle a tandem marathon canoe? Suppose it takes an average, continuous force of 50 Lbs1to propel a canoe at 7

    mph. 7 mph equals 10.3 ft/s. In linear motion, power is force x velocity so the average power is 50 Lbs x 10.3 ft/s = 515 ft-Lbs/s. Converting to Horse

    Power, 515 ft-Lbs/s 550 ft-Lbs/s per H.P. = 0.9 H.P. per 2 people. So it requires about 0.5 H.P. per paddler to travel at 7 mph.

    150 Lbs is very likely to be at the high end of the actual force required to overcome friction drag and wave drag in deep, calm water.

    Comparison of Power: Example Prone Push-Down Exercise vs. 7 MPH Tandem Marathon Canoe Analysis of the example for the prone push-down exercise gave us a result of 0.4 H.P. as the average power from one arm.

    Recall that the motion of the prone push-down exercise is very similar to the top hand motion of the canoe stroke.

    Analysis of the example for paddling a tandem marathon canoe at 7 mph gave us a result of 0.5 H. P. required per paddler.Conclusion: The top hand in the canoe stroke is capable of producing a large portion of the power required from a paddler in a tandem canoe.

    This simple analysis lends support to what many marathon canoe paddlers already know - effectively using the power of the top hand is

    a critical ingredient to maximize the canoe speed.

    Knowing that effective use of the top hands power is critical to maximizing the canoe speed leads to the question - What conditions

    enable effective use of the top hands power?

    1. The top hand must be directly above the blade for the entire duration of the power stroke.2. The blade must remain at a fixed distance (laterally) from the canoes keelfor the entire duration of the power stroke.3. The blade must be fully submerged and perpendicular to the canoes keel for the entire duration of the power stroke.

    In practice it means When the catch* occurs, the top hand must already be directly over the blade and it must immediately begin

    powering the canoe forward, continuing until the end of the power stroke.

    * The catch is that moment at the end of the recovery phase when the blade is quickly and fully submerged. It is the start of the power

    stroke.

    Comment: This comparison makes the implicit assumption that the power expended in one rep. of the prone push-down exercise can be repeated

    for each of the many, many strokes of paddling a canoe. That is not likely to be true. Perhaps1/3to

    1/2of the calculated power could be

    sustained. Also in calculating the power required to propel the canoe, the force used is likely at the high end of the actual requirement

    which may be between 30 to 50 Lbs. Even considering these reductions, the conclusion stays the same.

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 21

    Unintentional and Happy Consequences The seated, single arm lat pull downThe pedestal has made possible doing a seated, single arm lat pull down. It is easy to reach up and pull down on one of the handles while sitting on a

    low seat opposite the Total Gyms platform. To replicate the top arms paddling motion just take your arm across your body and grab the handle then

    press it straight down keeping your knuckles pointed forward. Holding onto a loop of rope that is around your foot will position your bottom hand

    approximately at the start-of-stroke location. When the total gym was at its factory height the handles were a little too low and the base was not

    wide enough to be stable during this exercise. To make this motion useful for training you should have additional weight added to the platform. One

    way to do that is with the addition of a bar to the platform and barbell plates as shown earlier in this document. Here are a few photos that show thearrangement and motion. Notice that my right hand is pulling the handle down on my left side and outboard of my left leg.

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    A Pedestal Design for the Total Gym Revision C 2009 Richard Butts Page 23

    Total Gym 1000 Series: Diagonal Support Attachment Height Total Gym 1000 Series: Platform Rail Length