A swimming test for prediction of maximum oxygen consumption

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1 A swimming test for prediction of maximum oxygen consumption Item Type text; Thesis-Reproduction (electronic) Authors Santeusanio, David Mario Publisher The University of Arizona. Rights Copyright is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 08/05/ :56:33 Link to Item

2 A SWIMMING TEST FOR PREDICTION OF MAXIMUM OXYGEN CONSUMPTION by David Mario Santeusanio A Thesis Submitted to the Faculty of the DEPARTMENT OF PHYSICAL EDUCATION In Partial Fulfillment of the Requirements For the Degree of Master of Science In the Graduate College THE UNIVERSITY OF ARIZONA

3 STATEMENT BY AUTHOR This thesis has been submitted in partial fulfillment of requirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author. SIGNED APPROVAL BY THESIS DIRECTOR This thesis has been approved on the date shown below: JACK H. WILMORE ProfeA&or of Physical Education "3 Date

4 DEDICATION This thesis is dedicated to the physical educators who continually strive to expand the boundaries of our field in research arid education. With the Lord's help may this thesis serve as a constant reminder of my commitment to excellence in the field.

5 ACKNOWLEDGMENTS It Is with my sincere appreciation that I extend thanks to Dr. Jack H. Wilmore for his help in advising and directing the writing of this thesis. His continuous encouragement and expert knowledge in this area of investigation was a tremendous advantage. Because of his loyal endeavors toward excellence and his impeccable honesty I hold him in the highest regard as a professional and a man. I would like to thank my committee members, Dr. Margaret B. Anderson and Dr. Fred B. Roby, for their valuable time and additional assistance. A sincere thanks is extended to my fellow graduate students for their help in the collection of the data. Also, a special thanks Is extended to Priscilla Gilliam without whose inspiration and support the writing of this thesis might have lagged on indefinitely. And fin ally, I wish to acknowledge that without the talents given me by the Lord this endeavor would never have reached its completion.

6 TABLE OF CONTENTS LIST OF TABLES... vi Page LIST OF ILLUSTRATIONS vi i ABSTRACT... vi i i CHAPTER 1 INTRODUCTION i Statement of the Purpose k 2, REVIEW OF LITERATURE... 5 Running/Walking Tests Cycling Tests... 8 Bench Stepping T e s ts EXPERIMENTAL DESIGN Subjects Determination of VO Meter Swim Statistical Analysis h RESULTS DISCUSSION SUMMARY APPENDIX A: SUBJECT CONSENT FORM APPENDIX B: METHOD USED TO CALCULATE STANDARD LOAD PROGRESSIONS FOR ESTIMATED MAXIMUM LOADS = 4.00 KG APPENDIX C: INDIVIDUAL SUBJECT CHARACTERISTICS APPENDIX D: PREDICTED VO2 MAX CALCULATED FROM THE REGRES SION EQUATION AND CONVERTED TO ML/KG X MIN LIST OF REFERENCES v

7 LIST OF TABLES T able Page I. Mean Subject Data for Total Group and for Each Group According to Training Level II. Correlation Matrix (N = 50) III. Commonality Analysis of Predictor Variables with VO- max in L ite rs /M in IV. Validity of Field Tests for Predicting Vo^ Max v i

8 LIST OF ILLUSTRATIONS F ig u re Page 1. Swimming Ergometer, Side View Swimming Ergometer, Overhead View Breathing Apparatus Scatter Diagram of Performance Time and VO. max in ml / kg x mi n Scatter Diagram of Performance Time and VO max in 1i ters/mi n v i i

9 ABSTRACT The predictability of maximum oxygen uptake (VO2 max) from performance time in an all-out 800 meter front crawl swim and selected physical characteristics was evaluated in 50 males, years of age. VO2 max was determined via the open-ci rcui t method during tethered swimming and compared with age, body weight, training level, and performance time in the 800 meter swim. Regression analysis revealed that body weight and performance time were the most signifie cant predictors of VO2 max. A multiple regression equation was constructed using these two variables to predict \10^ max in 1iters/min. The correlation coefficient was R = 0.84 (p < 0.001). Reliabilities for tests of VO2 max and 800 meter swim times were r = 0.96 and r = 0.99, respectively. The high re lia b ility of the field test and the strong relationship between VO2 max with body weight and performance. time indicates that the 800 meter swim test is a good predictor of VO2 max.

10 CHAPTER 1 INTRODUCTION Swimming Is recognized as one of America's most popular active sports. In a study conducted by Perrier (1979), swimming was found to be the second largest participatory sport in the United States, second only to walking. Twenty-six million people are involved in some form of swimming activity, including recreation, physical conditioning and competition. Swimming is one of the best physical activities for people of all ages, as well as for those who have various physical disabilities or incapacitating injuries. Vigorous, rhythmic activity performed in the water has been shown to result in significant alterations in fle x i b ility, strength and cardiorespiratory endurance (Andrew et a l. 1972; Clarke 1973; Stewart and Gut In 1976). Improving the general health and fitness of the participant is one of the most important benefits derived from swimming. In particular, swimming improves cardiorespiratory endurance capacity, the most important health related component of physical fitness (Taylor, Buskirk, and Henschel 1955; Astrand 1956; Mitchell, Sproule, and Chapman 1958; Newton 1963). Cardiorespiratory endurance capacity is best represented physiologically by the individual's maximal oxygen uptake (VO^ max) (Astrand 1956; Mitchell et a l. 1958; Newton 1963; Astrand 1973) VC^ max has traditionally been used to represent the individual's level

11 of fitness as well as to quantify changes in fitness with endurance conditioning. The actual measurement of oxygen consumption to determine VO^ max, a very costly and time consuming laboratory technique, is very impractical for use by coaches and teachers on a regular basis. A lternatively, methods, have been devised to predict or estimate max by evaluating performance on a particular work task with established norms (Brouha 1943; Astrand and Rhyming 1954; Balke 1963; Cooper 1968). These methods have proven valuable for field testing where many individuals are to be tested in a short period of time. It is the major purpose of the present study to devise such a field test that uses swimming as the work task. In the laboratory determination of VO^ max, the results of a number of investigations have indicated that the resulting value is highly dependent on the mode of testing (Carey, Stensland, and Hartley 1974; Cunningham, Goode, and Critz 1975; Str^mme, Ingjer, and Meen 1977; W?1more 1979; Secher and Oddershede 1975). Research in this area has shown that the various physiological responses to exercise are specific to the type of activity, i.e., running, cycling, and swimming. If valid and useful data are to be obtained when testing, athletes must be tested in a way that most closely resembles their performance during actual competition. Distance runners do not achieve maximal endurance performance when tested on a bicycle ergo- meter when compared to their maximal performance on a motorized treadmill. In swimming, swimmers should be tested in the water under

12 3 conditions most similar to actual competition. In this study tethered swimming was used to simulate the most optimal conditions for testing VO^ max of swimmers. A recent study by Bonen et al. (1980) revealed that VO^ max during free, tethered and flume swimming was not significantly different. The literature also provides evidence to support the theory that a specificity of training results in physiological adaptations in the body, which are specific to the type of training involved in each particular activity (Hartung 1973; Pechar et al. 1974; Magel et al. 1975; Wilmore 1979). Therefore, when evaluating and monitoring the physiological alterations in a training program the mode of testing used should closely resemble the training activity if the appropriate responses are to be elicited. With this in mind, when predicting the VO^ max of athletes or participants in selected sports or activities, the mode of testing should be used which is most specific to the particular type of activity used in training for that sport or activity. For example, a running test should be used to predict VO^ max in runners, a bicycle test to predict VOg max in cyclists, and a swimming test to predict VO^ max in swimmers. This would maximize the accuracy of predictions for each individual in their particular activity. There have been methods of field testing established which predict VO^ max by using running, cycling and bench stepping as the mode of exercise (Cooper 1968; Astrand and Rhyming 1954; Brouha 1943). Little or no research, however, has been reported which has established

13 a method of predicting the VO^ max of swimmers during swimming. Obviously, since physiological demands are specific to the task, it would be highly desirable to devise a method of testing the cardiorespiratory endurance capacity of swimmers which is more specific to the action of swimming. Statement of the Purpose The general purpose of this study was to develop a field test for estimating cardiorespiratory endurance capacity, i.e., maximal oxygen uptake (VOg max), for swimmers that could be used by coaches, instructors and others with an interest in swimming. Specifically, this study was designed to determine the relationship between VO^ max, as assessed during tethered swimming, and maximum performance in an all-out 800 meter swim for time.

14 CHAPTER 2 REVIEW OF LITERATURE Past research has established the validity of utilizing field tests as predictors of VO^ max. Most of these studies have been conducted with running, stationary cycling and bench stepping as the mode of exercise. A review of past research indicates that no field has been devised which uses swimming as the mode of exercise. Running/Walking Tests Balke (1963) and Cooper (1968) in it ia lly developed walk-run tests to estimate VO^ max on the basis of the distance covered in a given time period, or the time required to run a given distance. Cooper (1968), using a modification of the Balke field test for fitness (Balke 1963), developed the 12-minute walk-run test. In studying 115 Air Force officers, age years, he reported a correlation of r = between the distance covered in 12 minutes and VOg max. Ribisl and Kachadorian (1969) reported a correlation of r = between VO^ max and 1-mile run time, and an r = between V0^ max and 2-mile run time in college-age males. Katch and Henry (1972) conducted a study which dealt with the relationship between running performance and VO^ max in college-age males. In this study they reported a correlation of r = 0.54 in the relationship between 12-minute run performance and VO^ max. Using the same subjects. 5

15 an r = correlation was found in comparing 2-mile time and VO^ max. Gregory (1970), in comparing the 12-minute run and VO^ max of collegeage males, reported an r = Custer and Chaloupka (1977) determined the relationship between predicted V0^ max, as determined by the Astrand bicycle ergometer test (Astrand and Rhyming 1954) and performance in the 6, 9, and 12-minute runs for college women between the ages of 18 and 21 years (N = 40). Correlations of r = 0.45, r = 0.37 and r = 0.49 were found for the 6, 9 and 12-minute runs, respectively. The use of such a design, however, jeopardizes the accuracy of any correlation when a relationship is established using one predicted variable against a second predicted variable. Doolittle and Bigbee ( l 968) administered the 12-minute walk- run test to 153 ninth grade males. Using the rank order correlation technique, VO^ max and 12-minute run performance exhibited a correlation of r = 0.90 using only nine of these boys. The test-retest coefficient of re lia b ility for the 12-minute walk-run test (N = 153) was r = Maksud and Coutts (1971) reported a correlation of r = 0.65 between 12-minute walk-run performance and VO^ max using 17 male subjects, age 11 to 14 years. Reliability, established on a population of 80 male subjects, was r = Jackson and Coleman (1976) investigated the validity of distance run tests to predict cardiorespiratory endurance capacity for elementary school children, fourth through sixth grade. A factor analysis established the construct validity of the distance runs and gave

16 credence to the 9 and 12-minute runs. VO^ max and the 9-minute run correlated r = 0.82 for boys (N = 22), and r = 0.71 for girls (N = 25). VO^ max and the 12-minute run also correlated r = 0.82 and r = 0.71, respectively, for boys and girls. Krahenbuhl et a l. (1978), in studying 69 males and 48 females, firs t through third grades, reported multiple correlations whose coefficients for a 1600 meter run were slightly higher than r = when related to V0^ max expressed as a function of body weight. The test-retest re lia b ility coefficients ranged from a low of r = for firs t grade females to a high of r = for third grade males. Several investigators have examined the validity of the 600 yard walk-run test as an index of cardiorespiratory endurance capacity and reported rather low correlations with VOg max. Olree et al. (1965) reported a validity of r = for 76 males, years of age. Falls, Ismail, and McLeod (1966) reported a validity of r = in 87 adults, 23 to 58 years of age. Doolittle and Bigbee (1968) reported a validity of r = using only 9, ninth grade boys. Vodak and Wilmore (1975) investigated the validity, of the 600 yard walk-run test and the 6-minute walk-run test in 69 young males, 9 to 12 years of age, and found correlations of r = and r = 0.50, respectively. It is evident that field tests of running distance greater than 1 mile (1600 meters) or of a duration longer than 9 minutes have been successful with populations ranging from older adults to younger children.

17 8 Cycli ng Tests Attempts at predicting VO^ max from tests conducted with stationary cycling have also been reported in the literature. Astrand and Rhyming (1954) devised a test of submaximal effort, which included stationary cycling, to predict maximal endurance capacity. They reported that during the higher workloads of 1200 kpm for men and 900 kpm for women, the percent error of VO^ max prediction was only 6.7% for men and 9.4% for women. Unfortunately, coefficients of validity were not recorded in the original study. DeVries and Klafs (1965) included the Astrand-Rhyming test in their evaluation of several submaxima 1 tests which are commonly used for prediction of maximal physical working capacity. They reported a correlation coefficient of r = between actual and predicted V02 max in 16 college age men using a bicycle ergometer. Glassford et a l. (1965) reported an r = 0.77 between actual VO2 max and predicted VO2 max expressed in ml/kg x min from the Astrand-Rhyming bike test in 24 males, ages years. In a study conducted on 24 males, ages years, Wojtczak-Jarosowa and Banaszkiewicz (1974) reported that there was no significant difference between actual V02 max and VO2 max predicted from the Astrand-Rhymi ng Test. DeVries and Klafs (1965) also examined the relationship of actual VO2 max and VO2 max predicted from the Sjostrand bike test, as modified by Adams, Linde, and Miyake (1961). In this study they reported a correlation coefficient of r = between actual and

18 9 predicted VO^ max. From the above studies, stationary cycling tests appear to be very successful in predicting VO^ max. Bench Stepping Tests Several of the original field tests of physical fitness were based on the recovery heart rate responses following a standardized work task of bench stepping. Among the earlier, more popular tests are the Tuttle Pulse-Ratio Test, developed by Tuttle (1931), and the Harvard Step Test, developed by Brouha (19^3). These original studies did not attempt to predict VO^ max but rather, rated physical fitness on an arbitrary scoring index relative to recovery heart rates. In the evaluation of submaxima 1 tests commonly used for prediction of V02 max by devries and Klafs (1965), the Harvard Step Test and the Progressive Pulse-Ratio Test (Waxman 1959) were among those tests examined. The tests were correlated with the actual VO^ max of a group of 16 college age males with correlations of r = and r = 0.7U reported for each test, respectively. It is evident from these results and the results of other investigations reported in the literature, that predictive methods of determining VO^ max have proven to be very successful.

19 CHAPTER 3 EXPERIMENTAL DESIGN This chapter shall provide information concerning subjects, determination of VO^ max, the 800 meter swim, and finally a statistical analysis of the study. Subjects Fifty male subjects, ages 15*25 years, volunteered to participate in this study. Characteristics of this group can be found in Table 1. Due to the nature of the study, subjects had to have previous swimming experience to be eligible to participate in the study. A large degree of variation in swimming ability was noted in the subject population ranging from moderately skilled recreational swimmers to 1976 Olympic champions. Subjects from this age group were selected based upon the following. First, it was decided to examine a population that contained subjects with a wide variation in swimming ab ility and VO^ max, therefore, subjects who were currently engaged in a swim training program, as well as subjects who were not, were selected. The age range of 15 to 25 years is where most highly-trained swimmers are found and also includes many low-trained swimmers. Secondly, this age category would include a wide range of VO^ max values independent of age. The training level of each subject was determined for the purpose of 10

20 Table I. Mean Subject Data for Total Group and for Each Group According to Training Level. ' Age (yr) Weight (kg) 800 Meter Performance Time (sec) V02 max (ml/kg x mi n) VO2 max (li ters/min) High-Trained (n = 24) Trained (n = 16) Low-Trained (n = 10) Total (n = 50) Mean Sigma Range

21 - 12 identifying possible significant relationships within specific ab ility groups. Each subject was assigned to one of the following three training levels: High-trained (n = 24) those swimmers who were currently competing and had been training for more than 3 months at over 30,000 meters/week. Trained (n = 16) those swimmers who may have competed within the previous year and had been training between 3,000 and 30,000 meters/week for the previous six months. Low-trained (n = 10) those swimmers who had not competed within the past year, or who had never competed, and who had been training less than 3,000 meters/week for the previous six months. The subjects were informed as to the nature of the study and the extent of involvement required. Each subject was then allowed to observe all testing procedures and to experience the tethered swimming task prior to consenting to participate. The subjects indicated their willingness to participate by signing the form of informed consent (Appendix A) which had been previously read and explained to them. The experimental protocol and informed consent form had been previously reviewed and approved by the University of Arizona Human Subjects Committee.

22 - 13 Determination of V0 Max Each subject had his VO^ max determined during performance of the front crawl stroke while tethered to a cable and pulley system which allowed resistance to be applied systematically (Figures 1 and 2). This tethered swimming apparatus is similar to that developed by Costill (1966). A continuous work task was used to e lic it a maximum effort from the swimmer. This work task was developed by Curry et a l. (1979) and was designed to evoke maximum values within 4% to 5i minutes of exercise. Standard work protocols were established based on a short pretest to determine, the maximum resistance that an individual could support for 30 seconds. Using this pretest value as an estimate of the maximum resistance to be supported in the test its e lf, a progression for weight increments was determined for each subject (Appendix B). Individual differences in swimming ab ility were accounted for by adjusting the workload accordingly. The pretest consisted of having the subject swim while attached to the tethered swimming apparatus to determine the greatest amount of resistance in kilograms the swimmer could maintain for approximately 30 seconds. The actual test for determination of V0^ max began with a five minute warm-up period of tethered swimming at a base workload which was established as a percentage of the individual's predetermined workload as previously described above. The resistance was then increased systematically until the maximum resistance for each individual was achieved. Toward the end of the test, the subject experienced d if f i culty maintaining the original forward position in the water and began

23 14 eys Weight Pan Ru11ey Pool Deck Rubber Brick on Bottom Figure 1. Swimming Ergometer, Side View.

24 15 Bel Plastic Coated Cable Wooden Dowel Main Cable Figure 2. Swimming Ergometer, Overhead View.

25 to be pul 1ed backward as the resistance was increased. When the weights came to rest on the ground, the swimmer was instructed to give a final all-out effort to move forward to the original position in the water. This all-out effort was maintained until VO^ max was reached, as evidenced, by criteria established below or until the subject voluntarily terminated the test. Throughout the test, the subject breathed through a Hans Rudolph Respiratory Valve, Series #2700, which was attached to inhalation and exhalation tubing (Figure 3) This breathing arrangement allowed the swimmer to maintain a horizontal position in the water and perform the crawl stroke in a manner as similar as possible to free swimming.. Expired gases were collected and analyzed at 30 second intervals during the test using a Beckman Metabolic Measurment Cart. This instrument has been validated by Wilmore, Davis, and Norton (1976). Before and after each test, the 0M-11 oxygen and LB-2 carbon dioxide analyzers were calibrated with gases of known concentration. The concentration of the calibration gases was verified by the Scholander microtechnique prior to and during the study. Gas volumes were measured with a biased flow turbine which was calibrated daily, before and during testing, using a calibrated syringe (1.020 liters) at the flow rate estimated for that day's testing. Max VO^ was identified for each subject after careful adherence to predetermined criteria. Subjects performed a second maximum tethered swimming test within 1k days of the firs t test, with at least one day rest between tests, to determine test re lia b ility. Subjects whose maximum

26 17 Hans Rudolph Valve Series #2700 Exhalation Tubing # uuiiiiiiiiiniiiiiimihiinimmmuiimuiinuuiiiaiiim!} Mouthpiece Inhalation Tubing 'iiijiiniiinniniinniim ill Flexible Lightweight Tubing Adjustable Headgear Figure 3. Breathing Apparatus.

27 values on these in itial two tests differed by more than 2.5 ml/kg x min were retested a third time, with the two closest values being averaged to provide the criterion VO^ max value (Appendix C). For some subjects, a second (n = 4) or a third (n = 5) test could not be obtained. In these cases, as with all other subjects, the incomplete data was accepted only i f they met the following criteria 1) an R value equal to or greater than 1.1; 2) a sharp increase in ventilation without an accompanying rise in oxygen uptake; 3) a peak or plateau of oxygen uptake in the final minutes of the test. 800 Meter Swim Following the in itial test to determine VO^ max, subjects performed an all-out 800 meter swim, timed to the nearest 0.10 second, using the front crawl stroke. They were instructed to swim the 800 meters as quickly as possible, stopping only if necessary. All subjects started in the water and flip turns were allowed. The swims were conducted in a 50 meter pool. In several instances (n =6), testing schedules forced subjects to perform both the 800 meter swim and the VO^ max test on the same day. In these cases, the 800 meter swim was administered firs t. A minimum of one hour was then allowed before the V0g max test was administered. The 800 meter swim was administered twice and the best time was used in the analysis.

28 19 S ta tistica l Analysis Test-retest r e lia b ilit y coefficients, using the Pearson correlation method, for the VO^ max determination and the 800 meter swim were calculated to assure repeatability in obtaining those measures. The data on a ll 50 subjects were then submitted to regression analyses to determine the p re d ic ta b ility o f VO^ max from selected variables, i.e., age, body weight, training level, and performance time in the 800 meter swim. Those variables which were shown to be sig n ifica n t contributors to the prediction of VO^ max were then used to construct a m ultiple regression equation. Levels of s ta tis tic a l significance were determined on a ll tests with acceptance established at the 0.05 le ve l.

29 CHAPTER 4 RESULTS The subjects in this study formed a heterogeneous group characterized by a wide range of variability in. tethered swimming VC^ max (38.6 to 64.6 ml/kg x min), performance in the 800 meter swim (507.3 to 1,177.3 sec), and selected physical characteristics (Table t). Maximal values for oxygen uptake and the performance swim for individual subjects are displayed in Appendix C (n = 50). The test-retest re lia b ility coefficient for VO^ max, as determined by tethered swimming (n = 45), was r = 0.96 and the re lia b ility coefficient for the times in the 800 meter swim (n = 33) was r = The matrix of correlations between VO2 max, performance time and the various physical characteristics appears in Table II. Traditionally, oxygen consumption has been expressed relative to body weight, i.e. ml/kg x min and since swimming is a non-weight bearing activity it was decided to examine the VOg max relationship with 800 meter swim performance time with VO. max expressed both in ml/kg x min and in liters/min. Figures 4 and 5 are scatter diagrams relating the swimming performance times with VO2 max expressed in ml/kg x min and liters/min, respectively, for each subject. The simple correlation between performance time and VO^ max for the total sample (n = 50) was r = -O.63 (p < 0.001) when expressed in ml/kg x min, and r = (p < 0.001) when expressed in liters/min. 20

30 21 Table II. Correlation Matrix (N = 50) Age Weight Training Level Performance Time Age, yrs. Weight, kg. 0,40 Training Level Performance Time VO^ max, 1iters/min "0.56 V02 max, ml/kg x mi n l -O.63

31 O t/i o z <=} n m <st z ms -* noz>xx3o"nzi«it Q 0 > O A A A ' 0 - HIGH -T R A IN E D A - T R A IN E D D - L O W -T R A IN E D A o % o 0 e I I I I I t 1 L OXYGEN CONSUMPTION ML/KG X MIN ure 4. Scatter Diagram of Performance Time and VO^ max ml/kg x mi n. i n

32 z o o m </) Z rn k -i m o z» s ^ J o " n 3 ) m T J D O - h ig h - tr a in ed A - TRAI NED O- LOW-TRAINED OXYGEN CONSUMPTION LITERS/M1N Figure 5. Scatter Diagram of Performance Time and VO^ max in Liters/Min..

33 24 These correlations were not significantly different. Both the scatter diagrams and correlation coefficients indicate that linearity of regression can be safely assumed between the performance swim and VOg max, therefore, strengthening any predictive value further obtained from this relationship. Additional statistical analyses were conducted to establish those variables that will successfully predict VO^ max. Four predictor variables were selected, i.e., age, body weight, training level and performance time in the 800 meter swim. Each variable was examined for its individual relationship relative to the criterion VO^ max. A correlation matrix between all paired measurements was established in order to examine the interrelationships among the predictor variables and the relationship of each predictor to the criterion variable of VO^ max (Table II). It is undesirable in a regression analysis to incorporate the same variable into both the criterion variable and the predictor variable. This would heavily weight that variable as a predictor of the criterion and produces a spurious correlation. This would be the case if body weight were assigned as a predictor variable and were also contained in the criterion variable VO^ max (ml /kg x mi n r ). Consequently, regression analysis was conducted with VO^ max expressed in 1?ters/min. To determine the specific role of each of the variables in predicting VO^ max the data for the total sample were subjected to a commonality analysis. This analysis determined the multiple correlation for all of the predictor variables combined; identified those

34 25 single predictors which made significant contributions in predicting VOg max; and indicated the percentage of the total variance contributed by each predictor. The F-test was then used to determine if the contributions were significant at the 0.05 level. In Table III, the commonality of the predictors in the total correlation with VO^ max (1iters/min) can be seen. An value of 0.73 and an R = 0.86 (p < 0.001) represent the validity of the full regression equation calculated with all of the predictor variables. 2 The R values for regression equations containing each single predictor 2 variable separately are labeled TOTAL R. The corresponding independent contributions of each variable to the total correlation are labeled 2 2 UNIQUE R. The percentage that each variable represents of the R for the full regression equation is labeled PERCENT. Tests of significance 2 2 were computed for both TOTAL R and UNIQUE R for all Independent contributions and are labeled UNIQUE and TOTAL (Veldman 1978). Upon examining each of the variables in Table M l, those that made significant contributions to the total correlation both as independent predictors and in combination with each other were selected. The variables of body weight, training level and performance time were selected as the best set of predictors, and a multiple regression equation was constructed. The equation was as follows: Y ' = (Xj) (X2) (Xg) where: Y' is the predicted VO^ max (liters/m in); X^ is the body weight (kg) of the subject; X^ Is the training level (values of 1.0, 2.0, and 3.0 correspond to high-trained, trained, and low-trained, respectively)

35 26 Table III. Commonality Analysis of Predictor Variables with VO. max in Liters/Minute Predictor Variable TOTAL UNIQUE R2 PERCENT UN IQUE TOTAL Age Weight P =0.139 P = P < 0.001** P < 0.001** Training Level P = * P = 0.001** Performance Time P = 0.006** P < 0.001** Total R = 0.73, Total R = 0.8 6, P < Significant at the 0.05 level Significant at the 0.01 level

36 27 of the subject; and swim for each subject. is the performance time (sec) for the 800 meter The correlation coefficient for this regression equation was R = 0.85 (P < 0.001). It is noted from the above that training level makes the least absolute contribution of the three predictors. Although it is statistically significant and does account for some of the variance, its practical significance is,small. The absolute effect that training level makes on the predicted value of VO^ max is so small, ± liters/min, that its inclusion in the regression equation offers lit t le practical value. Consequently, training level was deleted as a predictor variable resulting in no significant decrease in the value of the multiple correlation coefficient, R = 0.85 to R = The final multiple regression equation was as follows: Y' = (Xj) (X2) where: Y' is the predicted VO^ max (liters/m in); X^ is the body weight (kg) of the^subject; and X^ is the performance time (sec) for the 800 meter swim. The correlation for this regression equation was R = 0.84 (P < 0.001). Using the final regression equation, a chart was constructed (Appendix D) that provides the complete range of predicted values of VO^ max from the two predictor variables. The variables were ranged in body weight from 45 to 117 kg. and in performance time from 500 to 1000 sec. Values of VO^ max in liters/min were converted on the chart to ml/kg x mi n. The standard error of prediction was 0.48 liters/min.

37 CHAPTER 5 DISCUSSION The maximal oxygen uptake values obtained from the subjects in this study were moderately high, i.e., the mean value was 52.5 ml/kg x min. This is most likely due to the large number of highly trained subjects (n = 2k) included in the study. These values are in agreement with those reported by other investigators measuring the VO^ max of swimmers (Magel and Faulkner 1967; McArdle et a l. 1971; Dixon and Faulkner 1971; Nomura 1978). The results of this study indicate that it is possible to predict VO^ max using body weight and performance time in an all-out, 800 meter swim as the predictor variables in a multiple regression equation. The coefficient of multiple correlation, R = 0.84, indicates a relatively O high degree of accuracy in the prediction of VO^ max. Approximately 70 percent of the variance in VO^ max was accounted for by these two variables alone. The standard error of prediction, i ters/min, is certainly within acceptable prediction accuracy, and approaches the magnitude of difference seen on repeat tests when VO^ max is measured directly. Body weight was found to have a large influence on the prediction of VO^ max, even though swimming is considered to be a non-weight bearing activity. Energy expenditure in swimming is theoretically divided into two components. One component involves the energy cost 28

38 of floating. Obviously, this is less for people who have relatively larger amounts of fat. The second component involves the energy cost of producing the propulsive force required to overcome water resistance. This cost here is less for the leaner, more streamlined individual. Although this theory indicates that both fat weight and lean body weight contribute in some degree to performance and VO^ max while swimming, body composition was not determined for the subjects in this study. Further investigation into the role of body composition in swimming performance is indicated. The predictor variable of performance time made a significant influence on the prediction of VOg max. This specific performance task was selected to most accurately reflect the individual's swimming endurance capacity as it related to VO^ max. It was assumed that the higher an individual's VO^ max the less time it would take him to finish the performance task. The distance of 800 meters was designated as the performance task because of the following reasons. First, a distance was needed which assured a predominant reliance on the aerobic pathways to supply energy. Results of running studies (Krahenbuhl et al. 1978; Ribisl and Kachadorian 1969) have indicated that an all-out run at distances in excess of one mile places considerable reliance on the aerobic energy system. Krahenbuhl et a l. (1978) showed that an 800 meter run and a 1200 meter run correlated r = and r = with V0^ max, respectively, in young males. Whereas, the 1600 meter (0.992 mile) run correlated r = with VOg max. Ribisl and Kachadorian (1969) demonstrated that an 880-yard run, a 1-mile run and a 2-mile

39 run correlated r = 0.67, 0.79 and 0.85 with VO^ max, respectively, indicating the duration of the run is critical to the accurate prediction of aerobic capacity. Jackson and Coleman (1976) have substantiated that 9 and 12-minute runs provide accurate estimations of endurance capacity.. Other running studies have reported similar results, indicating that distances requiring 10 to 12 minutes to complete adequately stress the aerobic energy system. Secondly, the results of an investigation by Jackson, Jackson, and Frank?ewicz (1979) indicate that the distance covered in a 12-minute swim is a valid measure of swimming endurance. An 800 meter swim normally takes between 10 and 15 minutes to complete. The average time to complete the 800 meter swim in this study was 11.8 minutes. This time frame places it within close approximation to a 12-minute swim. Thirdly, the performance task in this study was defined as the time to complete a fixed distance as opposed to the distance covered in a fixed time, as it allowed for greater accuracy in measurement. When swimming for a fixed time, the swimmer may be somewhere in the middle of the pool at the end of the test. Some accuracy is lost when estimating the total distance covered. Also, it was fe lt that it is considerably easier to perceive the magnitude of a task when the exact distance is known. This greatly facilitates the swimmer's pacing and strategy, which are important considerations with regard to subject motivation. Motivation plays a significant role in the administration of the 800 meter all-out swim. It is essential that the swimmers be motivated to push themselves to their peak aerobic capacity for this to be

40 considered a valid test of their maximum endurance capacity. A test is only as good as the effort provided by the swimmer. Upon selecting the variables to be used in the prediction, a question arose with regard to the inclusion of training level as a variable in the final regression equation. Although training level was a strong independent predictor of VO^ max, when combined with the other variables, it did not make a significant change in the prediction accuracy of the full regression equation. This phenomena is most likely due to the fact that training level is actually reflected in the performance time of the 800 meter swim. It would be expected that the more experienced, highly-trained swimmers would swim faster than the less experienced, low-trained swimmers*. Also, VO2 max values will be higher in the more highly-trained swimmers and,lower in the lesser-trained swimmers. Hence, this would account for the large contribution of training level as a single predictor of \J0^ max and the smaller contribution it made when combined with performance time. Of particular interest in this study was the inclusion of two subjects who were highly-trained distance runners with VO^ max values greater than 60.0 ml/kg x min when tested on the treadmill. They were inexperienced swimmers and were classified in the low-trained group. Although their swimming VO^ max values were rather high, 60.0 and 48.2 ml/kg x min, their swimming performances were two of the three slowest times. Obviously, this data serves to reinforce the concept of specificity. It strongly suggests, that endurance capacity is specific to the type of activity involved, i.e., a great endurance capacity for running

41 does not mean that you wm1 have a great endurance capacity for swimming. Also, this implies that specificity in testing methods is necessary to insure accurate and valid measurement of endurance capacity in any activity, all of which further supports the original purpose of this study, which was to develop a test of cardiorespiratory endurance capacity specific to swimmers. The success of predicting VO^ max from body weight and performance time in the 800 meter swim is indicated by the multiple correlation coefficient R = This value is far above the generally accepted levels of r = 0.60 for a useful fitness test (Mathews 1973). In order to comprehend the magnitude of such a correlation it is necessary to compare it with the success of other predictive methods. The. validity coefficients of various predictive methods reported by other investigators are displayed in Table IV. It can be seen that the 800 meter swim compares very well with other studies attempting to predict V02 max.

42 Table IV. V a lid ity of Field Tests for Predicting VO^ Max. Activity and Test n Sex Age Duration of Test Validity Coefficient Reference Run/Wa1k 12 min. run-wa1k 115 M min Cooper min. run-wa1k 9 M min Doolittle and 600 yd. run-wa1k 9 M yds Bigbee min. run-wa1k min. run-wa1k M F M F min. 12 min. 9 min. 9 min Jackson and Coleman yd. run-walk yds Falls et a l min. run-wa1k - M Col 1ege 12 min Katch and 2 mile run-wa1k M Col 1ege 2 mile Henry m. run-walk 117 M-F m Krahenbuhl et al min. run-walk 80 M min Maksud and Coutts yd. run-walk 76 M yd ree et a l UJ CO

43 Table IV. Continued. Activity and Test n Sex Age Duration of Test Validity Coefficient Reference 880 yd. run-wa1k 11 M yd Ribisl and 1 mile run-wa1k 11 M mile Kachadorian 2 mile run-wa1k 11 M miles mile run-wa1k 24 M miles yd. run-waik 69 M yd Vodak and 6 min. run-wa1k 69 M min WiImore 1975 Bicycle Astrand-Rhymi ng 16 M Col 1ege devries and Sjostrand 16 M Col 1ege Klafs I965 Astrand-Rhymi ng 24 M Glassford 1965 Bench Step Harvard Step 16 M Col 1ege devries and Progress ive 16 M Col 1ege Klafs 1965 Pulse-Rat io Swim 800 meter 50 M m Santeusanio front crawl 1980

44 CHAPTER 6 SUMMARY Fifty male subjects were studied in an attempt to determine the relationship of selected variables in predicting VO^ max while swimming. Age, body weight, training level, performance time in an all-out 800 meter swim, and VO^ max during tethered swimming were determined for each subject. Test-retest reliab ilitie s for the 800 meter swim and the VO^ max determinations were calculated and found to be R = 0.99 and R = 0.96, respectively. The variables were submitted to regression analysis to determine how each one related to V0^ max and to identify the best predictor variables. It was found that body weight, training level, and performance time in the 800 meter swim were significantly related (R = 0.68, -0.47, and -0.56, respectively) as independent predictors of VO^ max. The multiple correlation of all three variables was R = 0.85 (P < 0.001). It was noted that training level made the least absolute contribution of the three variables. Although it was statistically significant (P = 0.037)» its practical significance was small. Hence, training level was deleted as a predictor variable. The final multiple regression equation was constructed using body weight and performance time in the 800 meter swim as predictor variables. The multiple correlation for this regression equation was R = 0.84 (P < 0.001). The standard error of prediction was 0.48 liters/min. The 35

45 36 magnitude of this correlation was similar to correlations of other successful predictive methods using running, cycling, and bench stepping as the mode of exercise. The results of this study suggest the VO^ max while swimming can be predicted successfully based upon the relationship between an all-out 800 meter swim, body weight and actual VO^ max determination in men ages 15 to 25 years of age.

46 APPENDIX A SUBJECT CONSENT FORM P roject T it le : In v e s tig a to r: A Swimming Test fo r P re d ictio n o f Maximum Oxygen Consumption David M. Santeusanio This is a research study intended to develop a te s t fo r estim ating the endurance capacity o f an in d iv id u a l w h ile swimming the fro n t crawl stroke. The study will be conducted a t the U n iv e rs ity o f Arizona McKale Pool and will require each subject to report on fo u r separate days fo r te s tin g and to fill out a Pre-Exercise Medical H isto ry Form. Those who choose to take p a rt in th is study will be required to swim the fro n t crawl stroke in a s ta tio n a ry p o s itio n u n til near exhaustio n w h ile attached to a tethered swimming ergometer. The tethered swimming ergometer consists o f a b e lt th a t is placed around the swimmer's w a ist and attaches to a cable which is run through a series of. pulleys where a c e rta in amount o f weight will be added fo r the swimmer to hold up w h ile swimming. Expired a ir will be c o lle cte d and analyzed during the swim to determine how much oxygen your body used during the te s t. In order fo r the expired a ir to be co lle c te d i t will be necessary to breathe in to a s p e c ia lly designed mouthpiece throughout the te s t. Heart rate will be monitored during the te s t by the placement o f three surface electrodes on the chest. At th is tim e, you may e x p e rience some minor discom fort from skin abrasion which is necessary to assure proper attachment o f the electrod es. This discom fort is temporary and should disappear p r io r to e lectrod e placement. On a subsequent day you will retu rn to McKale Pool where you will swim 800 meters (approxim ately 875 yards) using the fro n t crawl stroke. The time i t takes you to complete the swim will be recorded and compared w ith your maximum oxygen consumption. I t will be necessary fo r you to repeat both o f these two testsw ith in two weeks o f each other in order to assure th a t we are o btainin g accurate measures. We will schedule your te s tin g periods in advance and you will be expected to a rriv e prepared fo r swimming. I t will take approxim ately fifty (50) minutes fo r each swimming ergometer te s t and twenty (20) minutes fo r each 800 meter swim. 37

47 A ll data c o lle cte d from the study will be c o n fid e n tia l and accessible only fo r the in v e s tig a to r and the thesis committee members. No re s u lts will be id e n tifie d w ith respect to an in d iv id u a l's name. Financial compensation fo r wages and time lo s t and the costs o f medical care and h o s p ita liz a tio n is not a v a ila b le and must be borne by the su b je ct. This consent form will be filed in an area designated by the Human Subjects Committee w ith access re s tric te d to the p rin c ip a l in v e s tig a to r or authorized representative o f the p a rtic u la r department. A copy o f this consent form is a v a ila b le upon request. 38 The o b je c tiv e s, procedures, and ris k s o f th is study have been explained thoroughly to me. I am requesting th a t I p a rtic ip a te in th is study and I understand the commitment o f p a rtic ip a tio n, but re a liz e I may withdraw from the study a t any time w ith out i l l will, o r a ffe c tin g my u n iv e rs ity standing. S ubject's Signature Date P arent's Signature^ ( i f under 18 years o f age) Wi tness Date Date

48 APPENDIX 8 METHOD USED TO CALCULATE STANDARD LOAD PROGRESSIONS FOR ESTIMATED MAXIMUM LOADS = 4.00 KG. AT TIME WORK LOAD CALCULATED AS FOLLOWS 0.00 Base work load (B^) = 0.25 (Est. Max)* 1:00 to Base work loads B^ through Bj. remain 4:00 the same. 5:00 Exercise work load (E.) = 0.50, (Est. Max)* r 6:00 Exercise work load ( 2)= work load for E, plus 35% of A, where A = difference between work loads for E, and E_.** I 5 6:30 Exercise work load (E,) = work load for E2 plus 28% of A.** 5 7:00 Exercise work load (E.) = work load for E- plus 22% of A.** 5 7:30 Exercise work load (EL) = (Est. Max.) kg. b 8:00 Exercise work load (E^) = E^ kg. 8:30 and each Add 0.25 kg. additional 30 seconds * All values rounded to nearest 1/4 kg with values ending in exactly 1/8, 3/8, 5/8, or 7/8 kg rounded to the next higher 1/4 kg. ** Cumulative rounding errors occasionally resulted in a situation in which one of these work loads had to be altered subjectively by ± 1/4 kg. Alterations were based upon: (A) smoothing progressions within corresponding load increments across estimated maximum loads, and (B) smoothing the progression within the given estimated maximum load across exercise work loads across E, to Er. I 5 39

49 APPENDIX C INDIVIDUAL SUBJECT CHARACTERISTICS 40

50 6 800 Meter Performance VOg max VO2 max Subject Age Weight Training (in seconds) Determinations Criterion Variable I.D. (yrs) (kg) Leve1* Best Time Other ml/kg x 1 II min III ml/kg x min ^ * /min

51 bj I.[ TT Meter Performance VOg max VO2 max Age Weight Training (in seconds) Determinations Criterion Variable (yrs) (kg) Level* Best Time Other ml/kg x m(n ml/kg x min 1/min I 11 III , I O OO 2.90

52 Subject I.D. Age (yrs) Weight (kg) Training Leve1* 800 Meter Performance (in seconds) Best Time Other VO2 max Determinations ml/kg x min 1 II Ml. vo2 Criterion Variable ml/kg x min 1/min ' *Training level: 1 = high-trained; 2 = trained; 3 = low-trained

53 APPENDIX D PREDICTED VOg MAX CALCULATED FROM THE REGRESSION EQUATION AND CONVERTED TO ML/KG X MIN 44

54 Body Weight (kilograms) AS 40 SI Sq ? fi Performance Time (seconds) g , ,2 69, , , S3,,3 52, 9 52,,6 32,,0 52,, , ,9 68, 8 69,8 39, , ; 8 96,3 99, , ,,8 52, A 32,,9 92,,2 91, , , , , , g ,, ,»3 52,,0 91, 7 91, ,2 61, , ,9 96,0 53,9, , ,,7 92, 0 92,,1 31,,e 31,, , , 8 99, g 36, * ,3 93 g ,1 52,0 32,,9 92, 2 91,,9 91,,6 51, 0 91,1 5^0 65 S ,0 60, 0 3o,g 38, , , , ,g 32,6 52,,3 32, 0 91,,7 51,,9 S I , , 1 99,2 58, ,2 99, , ,7 52,0 92,,8 31, 0 91,,5 91,,9 51, 0 30, , , 7 98,0 58, Q 59.9 so,g , , ,, ,13 51,, R ,3 59 a 58,9 97, , ,7 50, ,3 92,9 31,, ,,2 90,, Sop 63, ,0 39, 0 98,2 57, , ,4 90,0 94, , a ,, ,,0 90,, *.3 6»o 63, t , a 59, ,7 90,2 93, , g 91.6 SI,>3 s«,,0 90,, , , T 61, a ,2 98, 3 97,9 96, , ,0 93,9 93, ,7 91,0 SI, ,,6 99,,0 90* e 41, , , ,2 36, ,8 93,7 93, ,9 91,2 90,, ,,0 54,,2 90, ,5 3? 6 96,0 56, , , , , <",,7 30, 9 30,,2 98,, , ,8 37, s 36; , ,6 33,1 32, ,1 50,0 90,, ,,0 09,, , , ,2 95,3 94 g 59, *3 92,9 52, ,0 si , ,> ,,9 09,,7 09, 9 09, , a , , , , ,6 50,4 90,,1 09, 9 09,,7 09,,9 0?, ,, ,6 36,,2 99,9 34, ,0 92,0 32, , , og,,9 09, 7 49,,9 09,,3 09, ,, ,,0 99,2 30, ,1 91, ,1 SO , og,, ,,3 09,,1 08, ,, ,2 35,, , , ,3 91,9 91, , ,, ,,1 06,, OP ,,7 37, ,,1 94, , ,0 09,6 09,,3 09, 1 00,,9 08,,0 00, ,,2 97, ,,8 50,2 33, ,0 98, og 9 09*6 09,0 09,, ,,0 98,,6 08, a 49»? ,,0 36,, ,,0 53,0 93iS ,3 91 g 91, a 30,2 og g qg 6 09,0 09,2 09,,0 00, A 08,,6 00,,0 08, ,,3 36., o,e 3a,, ,9 92 a 92, ,2 50,8 30;9 90 S 09,9 og 7 qg 0 09, ,> ,,4 08,, ,,9 95, 9 S ,, , ,9 9*3,6 99, qg.f og 0 og 2 09,0 00,8 00,,6 00. a 00,,2 60,,0 07, 9 47,, ,,9 55,, ,6 S3,, , , ,3 38,0 og 7 49,9 og 2 qg 0 00,0 08,6 00,, OR,,0 07,,9 07, 7 47, ,,0 55,, S3,,0 92,9 92, i og 9 09,2 og ,0 00,,2 09, 6 07,,8 07,,7 47, 9 47, ,,5 94.,7 S3 9 33,3 92,, , , og ,2 00,,0 07. A 07,,6 07,,9 07, ,,8 99, ,,3 91,0 31, , ,9 09,6 09,3 og 0 08, ,1 08,0 07,, o?,,5 07,,3 47, 8 47,4 790 So,,7 93., ,5 32,, ,3 49 g ,3 09, ,0 07,,6 07. a 47,,8 07,,1 07, t? 46, ,,2 93.,9 52 A 92,2 31,, , ,9 Q? ,0 98, , g 07,7 07,9 07;, ,,1 06,,9 06, 0 46,7 0 O 33,,9 93, 0 52 Q 51,8 31,,3 50,0 90,0 90 O 00,7 qg 0 09,1 08,8 48, ,9 97,3 07,>2 07, 0 06,,9 00,,8 06, O 33,J V ,» , , , , , ,,0 06, 9 06,,7 96,,6 06, ,, ,, a , , ,9 06,,0 06, 7 06,,5 96,, ?,, SO,,2 49,0 49, , ,3 08,9 47, , ,7 06,,6 06, 9 06,,3 06,,2 46, ,, ,3 94,,9 49,3 9, ,0 47, , ,,0 06, 3 46,,2 06,,0 45, ,,5 50., ,0 09,,5 99,2 48, ,7 97,9 97, , ,5 06,3 06,,2 06, 1 46,,0 93,,g 49, 8 IS.0 45, ,, ,,2 48, , , , ,1 06,,0 OS. 9 45,,8 49,,7 45, SO,,7 SO., ,2 90,, P, ,2 97,0 46, ,1 99,9 05,, ,,6 45,,9 43, ,, ,0 48,, , ,9 96,7 06, , ,,6 09, 9 49,,0 45,,3 45, ,, ,,1 97,0 47, , ,9 49 g , ,,0 < ,,2 09,,1 45, I 15,0 910 <39,,5 98,, ,,0 97, , ,1 95 g 95,0 OS ,3 45,,2 03, 1 45,,0 49,, ,0 920 A9,>9 90., F 97,, , , ,8 46,0 09,8 49 ' ,2 05,8 43,,0 00, 9 44,,9 44,,8 44, 7 44,6 930 q<3,,0 98., ,4 97,, , , ,7 09, ,0 00,9 44,,8 00, 8 44,,7 04,,6 44, 9 44, ,,0 97., ,0 96,,7 46,9 46, , ,6 43,3 49, , g ,7 44,, ,,5 40,, ,,3 950 qf,,5 97, ,6 96,,0 96,2 96, , , , G ,6 44,3 44,, ,,3 40,1? 44,2 41,,1 960 q7,,1 46,, ,, , , , , ,> ,,1 40, I ,* ,,7 46,, ,9 99,, , g ,7 49, , ,,1 44. A 43,,9 OS,,9 43, ,,2 45,, ,9 99,, , ,2 qo o.O 43,9 43,,g 43, 6 43,,8 43,, ,, ,,9 95., ,, , a 49, , , A ,, ,6 43,, ,.4 JQOO 95,,3 09, ,8 99,,6 44, ,9 43, , ,, ,,4 4.5,, ,... where: Y' is the predicted V0^ max (1iters/min); X is the body weight (kg); X^ is the performance time (sec) for the 800 meter swim. Y'- = (X.) ( x J vn

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