Perceptual and Motor Skills, 1977, 44, 1319-1324. @ Perceptual and Motor Skills 1977
THE REACTIVE AGILITY TEST1P. CHELLADURAI, M. S. WHASZ, R. SIPURA University o f Western Ontario London, Canada Summary.-A new agility task incorporating the variations in the stimulus field and the instrumentation for measurement of performance is described. Reliability coefficients are very high (A38 to ,973) The stimulus variations that emanate from the spatial and temporal uncerca~ntiesprogressively increase the level of task difficulty. The described apparatus provides for adjustments in the amplitude of the task and in the control of spatial and temporal uncerminties to suit the requirements of a specific investigation.
Agility is generally considered as a n important factor of physical fitness
and motor ability. As ic is comprised of speed, power, balance, and coordination (Yuhasz, 1973, p. 2 3 ) , a test of agility is almost always included i n the various batteries of tests of fitness-performance. Coaches of different games point out the importance of agility for good performance in their respective sports. Consequently various forms of agility drills are administered as part of the training. Though there is a consensus regarding the relevance of agility i n sport tasks, the definition and treatment of agility in the literature does not clarify the concept sufficiently to be of practical use t o the teacher/coach. For instance, consider the traditional definitions of agility, as the following: the ability of the body or parts of the body to change directions rapidly and accurately (Barrow & McGee, 1971, p. 123). speed in changing body positions or in changing direction (Clarke, 1959, p. 222). the physical ability which enables an individual to rapidly change body position and direction in a precise manner (Johnson & Nelson, 1969, p. 100). the capacity of the individual as measured by the rate of changing position in space (Mathews, 1973, p. 144). the rapidity and ease with which the individual can change the direction or movement of the body or its parts (Yuhasz, 1973, p. 23). These definitions d o not take into account the variations in t h e stimulus field that trigger the agile performance. This is evidenced by the commonly used tests of agility in which the movement patterns are predetermined without any variation i n the stimuli, e.g., Illinois Agility Run, CAHPER Shuttle Run, Barrow Zig-Zag Run. W h i l e most sport tasks require agility, this requirement is mediated differentially by t h e type of stimulus conditions of each activity. In lThis study was supported by a research grant from the Research Council of the University of Wesrern Ontario. London. Canada. We wish to thank Dr. Albert V. Carron for his help. Additional material is'on file in Document NAPS-03039. Order from Microfiche Publications, P.O. Box 3513, Grand Centnl Station, New York, N. Y. 10017. Remit $3.00 for microfiche or $8.00 for .photocopy. Torrespondence concerning the article should be addressed to P. Chelladurai, Faculty of Physical Education, University of Western Ontario, London, Ontario, Canada.
P. CHELLADURAI, ET AL.
volleyball digging, for instance, the player has to adjust his movements to the variable location of the ball. On the other hand, the environmental conditions are stable for the discus thrower. More recently agility has been defined as the rapid and accurate movement of the total body in response to a stimzllzls and a model was presented to classify various types of agility (Chelladurai, 1976). The changes in the stimulus field could arise in the time of the onset of the stimulus, the location of the stimulus, or even a combination of both time and location. On the basis of the above mentioned variations in the stimulus conditions, agility was classified as simple where there was no variation in the stimulus field; tempo~al agility where there is variation only in the timing of appearance of the stimulus; spatial agility involving only spatial variation; and zlniversal agility which is a response to both temporal and spatial variations. This paper presents an agility task with its variations and describes the instrumentation used to measure the four types of agility. APPARATUS^ The apparatus is composed of an activator, a reaction mat, a control box, set of three timers, and a light display (stimulus field). Fig. 1 provides three views of the apparatus.
The activator is an "on-off" switch. The system is turned-on by pushing the button; mned-off when the button is pressed the second time. T h e Reaction Mat The reaction mat contains a pressure plate which, with the application of pressure, completes an electrical circuit. As the pressure is removed, the switch in the mat opens, stopping the input to one of the clocks and total body reaction is thus recorded. T h e Control Box The control box contains timing relays, latching relays, switching relays, and an integrated circuit board. The control circuit consists of a 100-HZ clock and a binary counter which is capable of counting from 0 to 11, corresponding to the 12 lights in the light display. The 100-HZ clock is fed into the binary counter, causing the circuit to count from 0 to 11 at 100 times a second. When the activator is hit, the clock input is removed from the binary counter which stops at a number. Thus the random selection of one of the 12 bulbs is assured. The above mentioned 100-HZ clock is also used to drive another smaller T h e total cost for the construction of the apparatus was 1200 Canadian dollars ($175 for the steel structure, $750 for electronic equipment, $75 for other supplies, and $200
for labor). Those who would like to construct a similar apparatus should allow for inflation and for higher labor charges.
REACTIVE AGILITY TEST
I -.i I
El.LIGHTS El +]PUSH
FIG. 1. ( a ) Top view of the Reactive Agility Apparatus, ( b ) Side view of the Reactive Agility Apparatus, (c) Frontal view of the display field of the Reactive Agility Apparatus
binary counter. When the activator is hit, this counter is stopped at a number from 0 to 3. This number, together with a timing relay, is used to produce a random 0- to 3-sec. delay necessary in some of the conditions. However, the investigator can set the control to manual delay at 0, 1, 2, or 3 sec.
A separate 100-HZ dock is used to run the three digital readouts employed to register the elapsed time (in .O1 sec.) for the measures ( t o be described below). When the activator is switched, input is fed into the first readout. The removal of pressure on the reaction mat terminates the input to the first readout and initiates the second readout. When the microswitch in front of the lighted bulb is pressed, the input to the second readout is removed and the input to the third readout is initiated. Finally, when the activator is pressed again, the input to the third readout is terminated. Thus, the three digital readouts exhibit the times for three different measures for one trial. After these times have been read and recorded, a single push button is used to reset all the readouts to zero. The readouts were calibrated against a Lafayette electric clock with accuracy of 2 .O1 sec.
P. CHELLADURAI, ET AL.
Light Display Twelve bulbs are distributed symmetrically and equidistant (8 ft.) from a point 4 ft. directly above the center of the reaction mat (see Fig. 1). The height and width of the display field and the distance between the bulbs and the mat are adjustable. A moveable Plexiglas plate with a microswitch at the bottom is mounted in front of each light. When the subject hits the plate the microswitch is activated which causes the light to go out. When a light comes on, n o other platemicroswitch combination can be used to turn the light off.
THETASK In general the task requires the subject move up to touch a bulb after it is lighted and return to his original position. More specifically the subject places both feet on the reaction mat and when ready presses the activator switch which lights u p a randomly selected bulb on the display unit. After lighting of the bulb the subject moves forward and touches the plastic plate in front of the lighted bulb which is turned off at the touch. The subject then returns to press the activator switch once more to complete a single trial.
Variations ilz the Stimr~lusField The apparatus provides for the manipulation of the stimulus presentation which initiates the performance. Temporal variations indude: lighting of a bulb instantaneously; lighting of a bulb at the specified time of 1 sec., 2 sec., or 3 sec.; and lighting of a bulb randomly between 0 to 3 sec. after pressing the switch. Spatial variations include: lighting of the center bulb and lighting of any of the 1 2 bulbs (including the center bulb). Any or all of the combinations of the temporal and spatial variations may be utilized for investigative purposes. It must be noted that the variations occur only in the presentation of the stimulus which triggers the performance. But the topography and amplitude of the performance is held constant.
The Measwres Agility may be operationally measured either by the time taken by the subject to leave the mat, touch the bulb and return to press the activator the second time (Total Time), or by the time taken to leave the mat and touch the lighted bulb (Forward Time). These two measures are derived from the following components of the task which the apparatus is designed to measure. ( i ) Total Body Reaction (TBR) is the elapsed time between the presentation of the stimulus (lighting of the bulb) and the subject's leaving the mat. ( i i ) Movement Time (MT) is the time taken by the subject to touch the bulb from the time he left the mat. (iii) Return Time (RET) is the time taken by the subject to return to the starter switch and press it after he had touched the lighted bulb.
REACTIVE AGlLlTY TEST
For the purposes of the present report, total time is taken as the measure of agility. Sixty randomly selected males from the freshman activity course at the University of Western Ontario were given 10 trials in each of the following conditions (variations in the stimulus field), whose order of presentation was random for each subject. Simple: The center bulb lighted up at the same time as the subject pressed the activator. Thus there was no temporal or spatial uncertainty. Tem#osal: The center bulb lighted up any time between 0 and 3 sec. after the subject pressed the activator. While there was temporal uncertainty, there was no spatial uncertainty. Spachl: Any one of the 12 bulbs lighted up immediately the activator was pressed. Only spatial uncertainty was present in this condition. Universal: Any one of the 12 bulbs lighted up between 0 and 3 sec. after the activator was pressed. In this condition, both temporal and spatial uncertainty were introduced.
RESULTS The descriptive statistics are presented in Table 1. It is noted that the mean scores progressively increase over simple, spatial, temporal, and universal uncertainty conditions, suggesting a grading of task difficulty in terms of information processing (Leavitt, 1975). TABLE 1 MEANSAND STANDARD DEVIATIONS OF TOTALTIMEAND FORWARD TIME ( I N SEC.) IN FOURAGILITY TASKS Measure
SD M SD
1.51 .17 .81 .14
Variable Tem~oral S~atial 1.93 .17 1.22 .12
1.92 .12 1.17 .09
Universal 2.07 .16 1.32 .13
The split-half and odd-even reliability coefficients for the four agility tasks (Total Time) are provided in Table 2. The odd-even values are higher for all the four tasks, ranging from 3 3 8 to .973. Thus, the performances on these four tasks are found to be highly reliable. Finally it must be pointed out that the distance between reaction mat and the display unit, and the height and width of the display unit (including the "The subjects and dara are part of a larger study at the University of Western Ontario.
P. CHELLADURAI, ET AL. TABLE 2 RELIABILIlY COEFFICIENTS FOR FOUR AGILITYTASKS(TOTALTIME) Simple
Split-half 336, ,911 350, .919 .415, .587 .743, 3 5 2 Odd-even .948, ,973 .913, .955 .721, 3 3 8 ,846, .917 Note.-The raw values are to the left, followed by values corrected for full test length by Spearman-Brown Prophecy Formula.
distribution of the lights) may be adjusted to suit the requirements of a specific investigation. REFERENCES BARROW,H. M., & MCGEE, R. A practical approach to measurement in physical education. Philadelphia: Lea & Febiger, 1971. CHELLADURAI, P. Manifestations of agility. CAHPER Journal, 1976, 42(3), 36-41. CLARKE,H. E. Application o f measarement to health and physical education. Eoglewood Cliffs, N.J. : Prentice-Hall, 1959. JOHNSON, B. L., & NELSON, J. K. Practical measurements for evaluation in physical education. Minneapolis: Burgess, 1969. LEAVITT, J. Task difficulty. In B. S. Rushall (Ed.), The status of psychomotor learnSports Science Assoc., 1975. ing and sport psychology research. Dartmouth, N.H.: Chap. 12. MATHEWS,D. K. Measurements in physical education. Philadelphia: Saunders, 1973. YUHASZ,M. S. Physical fitness and sports appraisal laboratory manual. London: Univer. of Western Ontario, 1973.
Accepied April 25, 1977.