Testing and Measurement in Exercise Prescription

1. Chapter 8 Test Administration and Interpretation Lee E. Brown, Andy V. Khamoui, Edward Jo

2. Chapter Objectives • Understand the purpose of testing. • Differentiate between validity and reliability. • Perform a needs analysis. • Determine appropriate testing protocols for specific performance variables. • Familiarize yourself with statistical measures.

3. Thought Questions • Why should a needs analysis consider both the individual and the demands of the sport? • Should test scores be shared with a team, or should they be kept confidential? • What is more important, reliability or validity?

4. Thought Questions (cont.) • Under what general conditions does a medical evaluation become more important? • What is a bell curve? Will the athletes you test on a team follow the bell curve?

5. Testing and Measurement • Testing is when initial decisions are made regarding the exercise prescription of such issues as frequency, intensity, and volume • Results used to evaluate performance and make decisions regarding the future of a program or individual

6. Testing and Measurement(cont.) • Test scores may be used in a research environment as part of an in-depth analysis of a sport or activity • Testing determines where an individual currently stands regarding his or her training status and, more importantly, where he or she needs to be headed

7. Testing and Measurement(cont.) • The final outcome of any training program is to arrive at a peak level of performance or to achieve some predetermined goal • Using the results of a properly designed and implemented testing and measurement protocol will enable the tester/coach to make objective decisions regarding an athlete’s program

8. Terms Used in Testing and Measurement • Population: an entire group of individuals sharing some common characteristic • Subpopulation: smaller sample of the population, containing a manageable number of people from whom to obtain performance measures. Results are then used to extrapolate data for the total population

9. Terms Used in Testing and Measurement (cont.) • Test: a tool used to measure performance • Measurement: the quantitative score derived from the test

10. Terms • Evaluation: placing a value on the measurement derived from the test • Assessment: putting the test, measurement score, and evaluation together: Choose a test, measure the score, and then make an evaluation based on a scale comparison.

11. Terms (cont.) • Normative scale: a postmeasurement scale derived from the scores of a peer group. Generally determined by placing highest score at the top and listing the descending scores in order of magnitude. • Criterion: an a priori scale whereby the break points are known prior to testing and each person must meet an established level of performance to achieve that value level

12. Test Selection • Tests chosen should be specific to the sport and to the population being tested • Physical tests include measurements of cardiovascular and respiratory function, strength, power, endurance, anthropometry, etc.

13. Test Selection (cont.) • Making the wrong decisions about an individual’s physical state can cause severe consequences for both the evaluator and client • Utilization of spurious data will ultimately lead to erroneous conclusions

14. Validity • Validity is the most important aspect of any assessment procedure • For a test to be valid, it must test what it is made to test • Five major types of validity: • Face – Concurrent • Content – Construct • Predictive

15. Five Types of Validity • Face validity: states that the test is logical on the surface • Content validity: states that the test includes material that has been taught or covered • Predictive validity: states that test scores can accurately predict future performance

16. Five Types of Validity (cont.) • Concurrent validity: states that the test is a measure of the individual’s current performance level • Construct validity: states that the test measures some part of the whole skill

17. Reliability • Reliability is the ability of a test to arrive at or near the same score upon repeated measurements in the absence of any intervention strategy • A reliable test should result in consistent scores • If reliability is high, then people who score well on a first test should also score well on repeated tests

18. Reliability (cont.) • Pearson r: establishes reliability on a continuum ranging between 1.0 and -1.0 • Reliability is not an either/or proposition but rather a floating scale of different levels • A negative correlation still represents reliability but simply states that as one score increases, another score decreases, thereby inverting the rank order of participants

20. Key Point A test may be reliable but not valid, while a valid test must always be reliable.

21. Assessment • Should include medical and exercise history; obtain a physician release if necessary, perform physiological testing, determine baseline nutritional status, and determine program goals • Objective of assessment is to provide a comprehensive view of the athlete, what he/she is capable of, what his/her limitations are, and any special needs that may need to be addressed

22. Assessment Should Include: • Medical history & PAR-Q: ask a few basic questions; use PAR-Q form • Physician release: medical release form describing each of the exercise components • Nutrition information: basic understanding of the person’s nutritional status • Needs analysis: evaluate the needs of the athlete and the demands of the sport

23. Needs Analysis • Assessment of an individual’s body fat, cardiovascular fitness, muscular strength/power, and flexibility • Needs of a particular sport or activity are unique and require different physiological performance levels of the athlete or client • Needs should include energy systems, duration of each repetition, duration of the entire event, muscle used, muscle actions used, range of motion, speed of movement

24. Tests for Measuring Strength & Power • Wingate anaerobic cycle test • Margaria-Kalamen stair climb test • Isokinetic velocity spectrum • Countermovement vertical jump • One-repetition-maximum power clean

25. Tests for Measuring Strength & Power (cont.) • One-repetition-maximum squat • One-repetition-maximum bench press • Bench-press body weight for total reps • 40-yard sprint • Standing long jump

35. Test Interpretation • Final and most complicated portion is making an evaluation of the scores • This involves placing a value on the recorded score so it may be used to help design a program of training specific to the individual • Once test data are collected, they should be interpreted accurately to coach and athlete in terms of norms and expected improvement

36. Order Scales • Main categories of test scores • Nominal • Interval • Ratio • Ordinal (sometimes)

37. Nominal Scores • Assigns a “name” to a category • Those that are coded for entry into a spreadsheet or statistical computer program • They represent the “real” item through the use of number • An example is coding sex as 1 for man and 2 for woman or vice versa

38. Interval Scores • Those that do not possess an absolute zero • This means that zero does not represent the absence of that variable but that it sometimes contains negative scores and there is no standard unit of difference between scores • One common form of interval scoring is temperature expressed in degrees Fahrenheit

39. Ratio Scores • Possess all traits of interval scoring • Have an absolute zero • This means a zero score is an absence of that variable, as in an elderly person’s vertical jump scores of 0 inches • Contain no negative numbers and there is an absolute scale of measurement between scores, such that lifting 50 lb is scored at half as much as lifting 100 lb

40. Ordinal Scores • Sometimes a fourth form of scoring by placing individuals in rank order • More accurately described as a ranking system rather than a scoring scale • Ordinal system ranks individual scores from top to bottom, highest to lowest, or greatest to least • All other scales of measurement can be listed in ordinal rank

41. Mathematical Measures • A few variables are associated with central tendency. • Enable the investigator to draw conclusions from the collected data • Provide the tester with valuable information regarding that data as a whole and each individual’s relationship to the overall group

42. Variables • Minimum and maximum: refer to the least score and the greatest score • Range: difference between minimum and maximum; represents the overall spread of scores as a whole number; maximum - minimum • Sum: total of all scores combined and added together: X1 + X2 + X3 + X4

43. Variables (cont.) • N: symbol used to denote totalnumber of people in the test group and is used in conjunction with the sum to arrive at other important variables • Mean: the arithmetic average derived from the sum divided by N; used most often; sum ÷ N

44. Variables (cont.) • Median: the exact middle of the total number of scores; not affected by outliers, shows a position only, and is rarely used for statistical calculations • Mode: the score that occurs most frequently; may be multiple modes or no mode at all; not affected by extreme scores and is not often used in statistical calculations

45. Distribution of Scores • Central tendency: the measure of the middle of a distribution of scores • When the scores are presented graphically, they can then be analyzed using basic statistical assumptions

46. Distribution of Scores (cont.) • Normal bell curve: the basic element and starting point of many statistical techniques • It is a frequency histogram that plots the number of times a score occurs on the vertical, or Y axis, against the raw number itself on the horizontal, or X axis • Scores increase as they move from left to right

48. Distribution of Scores (cont.) • Although many statistical calculations are based on the bell curve, it almost never occurs in real-life data • Positively skewed: curve with a long tail on the right and a hump near the left side of the graph

49. Distribution of Scores (cont.) • Negatively skewed: curve with a long tail on the left and a hump near the right side of the graph • Bimodal curve: where the frequency of scores was greatest in two different portions of the final outcome