What ACES Measures
The accurate measurement of human performance is important in evaluating movement. Accurate and calibrated equipment is essential for the clinician in his analysis of the movement.
The essentials of movement analysis includes the following parameters:
Position: The location of the limb segment in space.
Range of Motion, Velocity, and Acceleration: these values are dependent upon accurate position information. Range of motion is total position change; velocity is the rate of that change; acceleration is the rate of velocity change. These are computed values based upon the position information.
Force: an external influence of pulling or pushing action which causes movement to occur. An exercise system must be dynamically calibrated to provide meaningful information in pounds, kilograms or Newtons. A known force must be applied to the system and its effect upon the measuring device tabulated. Once a broad range of loads has been applied on the system and measured dynamically, a force calibration value is achieved. This calibrated information is stored in the computer memory to allow calculation of the subject kinetics.
Weight: gravity exerts a force upon all objects which results in that object having weight. Because gravity acts exclusively downward, biological motions on systems must consider gravitation. Gravity will act against a vertically upward motion and will aid a vertically downward motion. The computerized exercise system must account for the gravitational effect. Only a computerized system with a closed loop system can be calibrated for gravitational effect.
Torque: A force which causes rotation. Mechanically, torque is the product of the amount of applied force times the perpendicular distance of that force from the axis about which the object will rotate. Torque then is a function of both force and distance variables. The calculation of accurate torque must rely on the computer capability of the exercise system.
Position, acceleration and force must be considered in the measurement of dynamic torque.
The common denominator to any movement is that movement is composed of the following parameters: position, range of motion, speed of movement (velocity), acceleration (change in velocity), force, torque, work, power and fatigue. ACES can control these parameters in different modes. Some of the modes are:
Velocity training I Power training
Resistance training I Fatigue training
Resistance training I Fatigue training
ACES is designed to provide accommodating exercise resistance proportional to the force applied by the exercising user. However, ACES further enhances the unique effectiveness and utility of accommodating resistance by providing:
In addition to providing bi-directional, bilateral, or unilateral exercise, ACES can create User Defined exercises. User Defined exercises can include an entire range of variations on standard exercises that will allow the clinician or coach to create an exercise for a specific need of the user.
Most conventional exercises start in the upstroke or upward movement of the bar except for the Squat which is assumed to start with downward motion first. ACES has the ability to reprogram the starting position of any exercise.
There are two separate modes of exercises, with 3 sub functions, through which ACES controls the performance and data of an exercise. All five of these appear in the Exercise Modes box in the parameter screen.
Variable Velocity Mode
Variable Velocity mode is a passive mode where the machine accommodates the forces exerted by the user throughout the range of motion, and at the same time restricts the speed of movement to a predetermined velocity pattern which may simulate the dynamics of real motion. This mode offers accommodating resistance during acceleration and deceleration as well as during isometric holds.
In Variable Velocity mode, the velocity or speed at which the bar is permitted to move is maintained at a pre-selected value, regardless of how hard the user pushes against it. In addition to maintaining a constant velocity, ACES can be programmed to vary the velocity as a function of bar position in any pattern that the user may desire, thus the name Variable Velocity.
Variable Velocity mode exercise has a distinct advantage over resistance mode exercise: you don't need to know the individual's strength level in order to set up or begin exercising, nor is any adjustment necessary as the subject trains and increases in strength. The subject always pushes as hard as he or she can against the bar, and the computer automatically adjusts the resistance in order to maintain the desired bar velocity. In addition to maintaining a constant velocity, ACES can be programmed to vary the velocity as a function of bar position in any pattern that you desire.
Variable Resistance Mode
Variable Resistance is the mode most similar to traditional weight training. In the variable resistance mode, a level of force can be set which the user must exert, in order to move the bar. In addition to maintaining a constant resistance, ACES can be programmed to vary the resistance as a function of bar position in any pattern that the user may desire, thus the name Variable Resistance. This feature allows the user to program greater or lesser amounts of weight, at any point in the motion, to accommodate for injuries and natural mechanical Inefficiencies. It is a well known feature of anatomy that the mechanical advantage of most muscles changes as the associated body joint is flexed or extended. The variable resistance mode allows an exercise to compensate for this change, becoming progressively easier or more difficult, and thus maintain a more constant muscular exertion through the entire range of movement.
The reporting changes in speed as a function of changing load is an excellent complementary information to the force/torque, curve the discovery of certain pathological cases, as well as talent recognition in youths and adults are only a few examples of the benefits of this mode.
The following three functions are all sub functions of the Variable Velocity and Variable Resistance Modes. Each sub functions can be used in either the Variable Velocity Mode or the Variable Resistance Mode.
Work Training is a velocity mode exercise with an additional feature. Rather than specifying the number of repetitions to be performed, work training Specifies the total amount of work to be performed. Whether the user generates a great deal of work with only a few repetitions and greater force, or many repetitions with little force, a certain amount of work must be completed. Work is defined as the product of the force on the bar times the distance the bar is moved, and thus is proportional to the energy expended during exercise. Work training exercises, when performed at a continuous pace with a reasonably high amount of work, have a cardiovascular training effect as well as a muscular training effect.
Fatigue Training is a velocity mode exercise with an additional feature. Rather than specifying the number of repetitions to be performed, fatigue training specifies the degree of muscular fatigue to be achieved during exercise. Fatigue is measured by comparing the average force for each repetition (upstroke portion) with the highest average force measured for all repetitions. This measurement is expressed as a percent of the highest average force, so that your fatigue level starts at 100%, and drops as your average force level drops. For example, a 75% fatigue exercise would continue until the average force produced in two consecutive repetitions was 75% or less of the average force for the strongest repetition. Fatigue mode can be viewed as a means to increase endurance, by gradually increasing the amount of repetitions that the user can do before falling below the fatigue floor. The fatigue mode is also an extremely efficient way of maintaining intensity in an exercise, as the user will need to maintain a certain level of intensity to continue the exercise.
Timed Exercise can be performed in either variable resistance or variable velocity mode. Rather than specifying the number of repetitions to be performed, exercise specifies the period of time. At the end of that time period, that exercise will terminate regardless of the amount of work or repetition completed.
The application of all these exercise modes will become obvious to anyone who becomes familiar with the system. There is no replacement for experience in working with the system, however, there are some basic guidelines that serve as good starting points in setting levels on ACES for specific types of training. There are six basic categories that serve as outlines for the most common uses:
High level strength
Each of these categories indicate a corresponding change in the level of resistance or velocity. In order to determine the proper levels for each user, a test should be performed to determine the maximum speed at which the user can perform the exercise. This test can be performed in the variable resistance mode by setting the resistance to a minimal resistance (1-5 lbs.), or by increasing the variable velocity to a very high speed. After several trials the highest speed the user is capable of obtaining can be determined. That maximum will be considered 100% of speed value.
The following are suggested percentages of this speed value:
Set Duration for Muscular Endurance: 45 seconds - 3 minutes
High level strength - 8% - 15% (few repetitions)
General strength/conditioning - 12% - 20%
Power - 30% - 40% (highest power output occurs at these levels)
Muscular endurance - 40% - 60% (high speed power events)
Set Duration for Cardiovascular Endurance: 3 minutes or longer
Cardiovascular Endurance - 35% - over 60%
Speed Training - over 60%
Very common questions are:
How much work should be assigned to an exercise?
At what fatigue level should the set be terminated?
What is the right number of repetitions for a specific training program?
One approach to this situation is to determine the duration of the activity that needs improvement. Then, assign that time duration to an exercise. At the end of the exercise the system reports the total amount of work, the number of repetitions performed, and the fatigue level at the end of the set.
The next step will be to assign to the Work Mode, that amount of work to an exercise program. When the user reaches a point where they can achieve the same amount of work in 15% to 20% less time than those performed initially, the program can be changed to repetitions.
In Variable Velocity Mode, assign 10% - 15% more repetitions than were initially performed. Once the user can perform 20% to 30% more work than the initial amount, the program can be changed to the Fatigue Mode.
The goal should now be to complete as much work as possible and as many repetitions as possible within a set. The total amount of work performed should become greater than what was performed in the other training modes.
The purpose of demonstrating this approach is to make the user understand that there is a very close relationship between the different modes. The information reported in each mode can also be used to tailor the program more accurately and more specifically to the needs of the exerciser.
Diagnostic Evaluation is a feature that allows ACES to measure the user's maximum capabilities. These measurements are used in a variety of ways by ACES.
When diagnostics are being performed up to three values are measured and recorded:
Range of motion - The range of motion is established by going through a single repetition.
Maximum speed throughout the range - The maximum speed is established by setting resistance to a minimal value and then have the user move the bar through the range of motions as fast as he can.
Maximum force throughout the range - The maximum force of the user is established by exerting maximum effort throughout the range of movement.
These values are entered into the system to allow the system to adjust to the user with an even higher degree of accuracy. The maximum speed and force recorded during the exercise are used by the system to determine the proper valve adjustment which are best fitted to the individual's performance, whether it is an improvement in performance due to training, or a decrease in performance due to injury.
When Diagnostics are performed in the manual mode, the values are only stored for as long as the same exercise is being performed. Diagnostics in the programmed mode will be stored in the memory of the program and can be updated from time to time. You may have only one set to Diagnostic values per each exercise.
Sampling Period for Rehab Data
The system allows 5 minutes or 250 repetitions, whichever comes first, for Rehab Sampling. During this period of time, the system collects all Rehab data on every repetition performed for statistical analysis and graphical presentation. The information in summarized in Rehab Table, Rehab Ratio, Stamina Report, Wave form, and the fatigue curves. The Sampling period does not effect any of the exercise ratios. An exercise can be performed for over 250 repetitions, but data will only be measured for the first 250 repetitions.
Accommodating Velocity (Acceleration)
Just as a continuously varying force output is characteristic of natural movement, so too is variable velocity. Nearly all movement involves acceleration. When a javelin thrower releases the javelin, the angular velocity at the shoulder joint accelerates from a speed of zero to about 4,000 degrees per second and when a baseball pitcher throws a fast ball, his arm accelerates to nearly 6,000 degrees per second. Just as in athletics, acceleration is also involved in the natural activities of daily life. In walking for example, the angular velocity about the knee alternately accelerates and decelerates between zero and approximately 360 degrees per second, and when running the velocity approaches 1,500 degrees per second.
In order to train with similar neuromuscular patterns that occur in real life, it is necessary to program the movement to this natural phenomenon. Only ACES established this today.
In restoring normal functionality then, acceleration and high velocity exercises are essential components of the therapeutic or training process.
With the ability to program ACES to operate in specific velocities throughout the range of movement from zero to over 1,000 degrees per second, ACES distinguishes itself from any available modalities today. As the operating velocity of ACES varies automatically throughout the range of motion, it trains the neuromuscular system in the most efficient method to achieve optimal results. ACES provides the appropriate resistance for each exercise, while approximating the acceleration patterns encountered in natural movements. This is the greatest achievement in intelligent exercise systems today and for the future. ACES thereby approaches ultimate specificity in recruiting and training the appropriate muscle fibers and neuromuscular pathways associated with each position in the range of motion of an exercise.
Programmable Accommodation Resistance
ACES provides an accommodating resistance, that is, the exercise resistance is directly proportional to the intensity of effort applied by the exercising user. This feature is uniquely advantageous in rehabilitation and training, as the exercise resistance automatically accommodates to varying strength levels throughout the range of motion of the exercise, from repetition to repetition throughout the duration of the exercise, and from session to session throughout the complete rehabilitative or training process. The phenomenon of varying force output in a single movement is a consequence of the biomechanics of the joint system and the physiological length-tension curve of the musculo-tendinous unit. The actual muscular force output varies through the range of motion based upon the interaction of the muscle and bones. Variable force, then, is characteristic of virtually every human movement. Only intelligent systems, such as ACES, can precisely accommodate the resistance.
Because of the body lever system, even if a muscle contracts with exactly the same force throughout the movement, the resultant force on the end of the lever arm such as the hand or the foot, varies at each position in the range of motion. As the athlete or the patient's strength varies due to change in the mechanical advantage of the linkage of his limbs, and also due to fatigue with each subsequent repetition, the accommodating computerized system responds instantly, automatically varying the force to match exactly that being applied by the athlete or the patient. Only a computerized controlled system can achieve this effect.
ACES assists the coach or the physical therapist to determine the load that should be put on a joint or limb for a particular exercise, or for a particular rehabilitation session, as this is accomplished automatically by the computer as the patient or athlete applies force to the exercise system. The optimum rate of improvement for each patient or athlete is achieved using the appropriate exercise intensity in each movement and exercise. By providing automatic instantaneous accommodating resistance proportional to the patient's or athlete's training progress, ACES is the safest and most effective exercise method available. As the exercise apparatus develops resistance only in proportion to the amount of force the patient applies, there is little danger of over stressing muscles, joints, or connective tissues.
Specificity of Movement
In addition to providing programmable accommodating resistance and programmable acceleration, ACES features unprecedented versatility in duplicating natural movements. The overwhelming weight of contemporary scientific evidence supports the advantage of those exercise patterns which duplicate, as closely as is practical, the force and the velocity of the particular movement. Only ACES can program the velocity and the force to resemble the real movement associated in normal and supernormal athletic performance. As far as rehabilitation, ACES is easily adaptable to each individual patient, permitting simulation of natural movement patterns previously unavailable with conventional resistance exercise systems. The value of an exercise therapy prescription and the validity of performance data need no longer be compromised by lack of movement specificity.
ACES is a resistance exercise system combining accommodating resistance, acceleration, and specificity of movement for optimum progress of the therapeutic and training process. As such, it is an invaluable tool for the coach, physician, and therapist. But ACES is also much more. Being a computer system, ACES displays and collects data and allows real-time motivational feedback for the patient, athlete and the person that trains. All of the relevant exercise variables are measured and integrated into a database easily understood for the athlete or the patient performance status. This database accumulates past and present information for the force, velocity, work, power, endurance and many more parameters related to the patient or athlete or normal person functional capacity. All of these variables in exercise are interrelated, and are measured concurrently with accuracy to characterize the performer.
Combined with a simplified computer data acquisition system, ACES provides the most economical, efficient, and effective means of administering, evaluating, and reporting athletic and rehabilitative exercise available today.
The science of exercise reaps the benefits sown by the past decade's explosion of technological advances with the introduction of ACES Computerized Exercise System. For the first time, there is a computerized exercise system that has the capability to monitor an individual's present physical status, ability, and daily progress while exercising.
Computerized DataBase System
ACES allows a sophisticated data system to utilize commercial software packages such as Lotus 123 or dBASE-H to manage a total clinical operation.
ACES stores all the data on a diskette and this data can be fed into a total database measurement. You may also record the directory of patients. The injury records save you time by leading you efficiently through a series of standard data entries - patient name, age, sex, height, weight, etc. You simply type in a brief response, and the computer does the rest of the busy work. You can record the following information:
Activity during which injury occurred
Type of injury
Location of injury
Severity of injury
New or recurrent injury
Requirement for a physician
Duration of treatment
Each category is broken down into responses meaningful to the athletic trainer, physician or coach. You may also add entries tailored to your own practice; no time-consuming copying of information; no illegible handwritten entries; no need for costly clerical help.
With the database system you can generate printed reports in minutes, saving literally days of valuable time. Simply tell the computer which record categories to scan and the program automatically generates a frequency count with row and column totals.
The most exciting ability is to combine the data management with the data stored from the subject performance. This allows you to report any specific data for range of movement, force curve, velocity curve, torque curve or statistical information. These data can be compared to standards for efficient evaluation of the person training on the exercise system.
A unique feature that sets ACES apart from all the other exercise systems is ACES interface between equipment and a state-of-the-art computer. This high technology advances the activity of exercise past the drudgery of lifting weights, weight stacks and simple hydraulic pneumatic valves and plays it in an exciting, colorful and informative world of resistive exercise.
The programming of ACES contains an extensive amount of possibilities for the person who strives for the fastest and the most efficient way to build up strength, endurance, power and general physical fitness. ACES is also invaluable for the physical rehabilitation specialist, the sports trainer and the researcher, since its computer graphics and printouts contain information that no other sophisticated rehabilitation equipment can possibly approach.