INTRODUCTION

North Americans have become more physically active and are participating in exercise and diet programs for health, recreation, and well-being purposes. It has become important to clarify and quantify the specific elements which lead to health and fitness.

According to

the Position Papers of the American Dietetic Association (ADA) and the Canadian Dietetic Association (CDA), "the importance of diet and healthful food choices in optimizing health status, fitness levels, and athletic performance has been recognized by both participants and professionals" (1987, p. 934; 1993, p. 693). They further state that adolescent athletes require accurate information establishing safe weight and body composition goals. Another important factor addressed by the ADA position papers was that the diets of some adolescent athletes, particularly females, are poor in providing energy and nutrients. Since adolescents' nutrition requirements are high due to growth and development factors, involvement in competitive sports increases the importance of nutrition.

Potter and Wood (1991) stated that athletes' desire for accurate and practical nutrition information represents an increasing challenge and responsibility for dietitians, teachers, and coaches. Further, they note that more instructional materials need to be developed. There is, however, a lack of research focused on developing the most effective ways to educate athletes about sports nutrition.

Warren, Bonner, and Stitt (1985) indicated that coaches were in need of additional information regarding fluids, food supplements, and methods for gaining or losing weight. In addition, they stated that nutrition information should be developed and presented in a scientific format for implementation by coaches. Other studies have focused on the nutrition knowledge and practices of high school athletes. Douglas and Douglas (1984) found that athletes had limited knowledge of nutrition and that females did not use their knowledge in making proper food choices.

Contento, Manning, and Shannon (1992) stated that "nutrition education generally had a positive effect on cognitive outcomes such as nutrition knowledge, diet-related skills, behavioral expectations, and self-efficacy" (p. 247). However, according to Potter and Wood (1991), Contento et al. (1992), and Schlicker, Borra, and Regan (1994), even though gains in knowledge represent a step forward in nutrition education, these programs tended to have little effect on behavior.

Werblow, Fox, and Henneman (1978) conducted a study with female athletes and concluded that nutrition education programs must provide information that is relevant to the individuals involved. The study had two key variables: weight control and sports performance. They suggested that interest in sports nutrition by female athletes may be the vehicle for an effective approach to general nutrition education.

Past studies of nutrition knowledge and practices with teenage athletes have invariably discussed the motivational factors required to enhance the learning and application of sound nutrition principles. Two motivating factors that have been identified in several studies are weight control and level of performance. These studies also emphasize the need for nutrition education as an essential component of the training program for female athletes.

Adolescent females tend to have nutritionally inadequate diets and thus they may be at great risk when taxing their bodies in rigorous training schedules. Athletes as a group are very vulnerable to erroneous nutrition information as they attempt to gain a competitive edge (Pratt & Walberg, 1988).

The purpose of this study was to evaluate the effectiveness of an original sports nutrition education program in improving nutrition knowledge of high school varsity football players in Southern California.

METHOD

Subjects

A total of 72 females ranging in age from 14 to 18 years (74% of whom never took a high school course which included a nutrition component) from eight high school varsity softball teams participated in a 6-week study. These subjects formed the Baseline League of Southern California. They were randomly selected (based on gender, active participation in sports, and being a full-time student) and were evenly divided into a control or experimental group.

Ergogenics, dehydration, precompetition meal, energy sources, vitamin and mineral supplements, and weight control were presented to the experimental group prior to posttesting in two 45-minute lectures once a week. In addition, flyers, handouts, and demonstrations were provided. The instrument used as the pre- posttest was a 24-hour dietary recall. A pilot study was administered to 15 females to assess validity and reliability of the information in the instrument.

All subjects completed a modified version of the Nutrition Knowledge and Attitude Questionnaire (Werblow et al., 1978) as pre- posttests in order to evaluate their nutrition knowledge level. A 24-hour dietary recall was also administered with the pre- and posttest to determine any changes in selection of precompetition meals, types of fluids consumed prior to and during games, and general dietary habits. All information was used to evaluate changes over time resulting from nutrition education. The 24-hour recall was analyzed using the Food Processor Program (1984).

The completed instrument was scored by awarding points for correct nutrition knowledge responses on the basis of degree of certainty of the answer on a scale of 1 to 5; the instrument had a total possible score of 200 (5 points/question).

Data Analysis

Pearson product-moment correlation coefficients were computed for nutrition scores as they related to grade level, pre- and posttests of nutrition knowledge, and number of sports played. Only paired pre-and posttests were included in the study. A correlated t-test was used with the pre- and posttest scores to determine significant (p [less than] .05) changes in knowledge as a result of nutrition education.

RESULTS

Nutrition Knowledge

The pretest scores for the control group ranged from 188 to [Mathematical Expression Omitted]; for the experimental group, the scores ranged from 115 to [Mathematical Expression Omitted]. Table 1 shows that the two groups were not significantly different in nutritional knowledge as measured by pretest questionnaire scores.

The control group posttest scores ranged from 116 to 159, and the experimental group scores ranged from 126 to 195. The t-test indicated significant posttest differences in the mean score for the two groups, favoring the experimental group (Table 1).

Table 1. Nutrition knowledge Pretest and posttest Scores for
experimental and Control Groups.

Group                   Mean [+ or -] SD          t             df

Pretest Scores

Control (a)           135.74 [+ or -] 9.43
                                               .44(*)           70
Experimental (b)      134.81 [+ or -] 8.73

Posttest Scores

Control (a)           133.91 [+ or -] 9.47
                                                6.03(**)        70
Experimental (b)      152.68 [+ or -] 15.98

Change in Scores of Pretest to Posttest

Control (a)           -1.83 [+ or -] 11.04
                                                7.01(**)        70
Experimental (b)      17.87 [+ or -] 12.68

(a) n = 35. (b) n = 37.

* p [less than] .1, two-tailed pooled estimate of variance. ** p
[less than] .01, two-tailed pooled estimate of variance.

The overall change in mean total scores of both the control and experimental groups was significant. The control group had a negative overall mean change, whereas the experimental group's mean score showed a significant increase of 17.87.

Results of the Nutrition Knowledge Questionnaire showed possible changes in precompetition meal selection as a result of the education program. This improvement was evident in the experimental group. Table 2 shows that t values for the pretest had no significant difference, and the mean of the posttest scores was higher for the experimental group than that of the control group.

Table 2. Scores of Nutrition Knowledge Questions Concerning
Precompetition Meal, Fluid Selection, and Nutrition Misinformation

Group                 Mean [+ or -] SD             t              df

Precompetition Meal Pretest

Control (a)           3.31 [+ or -] .54
                                                 .01(*)           70
Experimental (b)      3.32 [+ or -] .60

Precompetition Meal Posttest

Control (a)           3.53 [+ or -] .71
                                                 2.68(**)         70
Experimental (b)      3.99 [+ or -] .74

Fluid Selection Pretest

Control (a)           3.42 [+ or -] .54
                                                 .93(*)           70
Experimental (b)      3.30 [+ or -] .53

Fluid Selection Posttest

Control (a)           3.61 [+ or -] .67
                                                3.61(***)        70
Experimental (b)      4.13 [+ or -] .56

Nutrition Misinformation Pretest

Control (a)           3.07 [+ or -] .47
                                                  .23(*)         70
Experimental (b)      3.10 [+ or -] .60

Nutrition Misinformation Posttest

Control (a)           3.01 [+ or -] .62
                                                  6.08(***)      70
Experimental (b)      3.91 [+ or -] .63

(a) n = 35. (b) n 37.

* p [less than] .1, two-tailed pooled estimate of variance. ** p
[less than] .1, two-tailed pooled estimate of variance. *** p [less
than] .01, two-tailed pooled estimate of variance.

The t value of the pretest for fluid selection showed no significant difference between the two groups; however, findings on the posttest for the experimental group showed a significant increase in correct responses regarding nutrition misinformation for the experimental group, but not in the pretest question responses.

Table 3 shows the lack of correlation between the control's and the experimental group's pre- and posttest scores with selected characteristics: grade level, previous nutrition education, and number of sports played.

Total 24-Hour Caloric Intake

Pre- post-24-hour dietary recalls indicate the caloric intakes, as shown in Table 4. The overall mean caloric intakes for pre- 24-hour recall for the control and experimental groups were 1683 and 2054 calories, respectively, and for the post intakes, 1793 and 1892 calories. Both intakes were low for meeting the nutrition needs of female adolescents involved in competitive sports. It is of interest that there was a decrease in calorie intake in the experimental group between the pre-and posttests periods. This decrease was significantly greater than in the control group which showed an increase (-162 kilocalories vs. +110).

The mean precompetition meal distribution of protein, carbohydrate, and fat by percentage of total calories consumed by the two groups is shown in Table 5. The overall percentage of fat consumption for the control group increased from the pretest period, while the opposite was true for the experimental group. Also, the overall percentage of carbohydrate consumption increased for both control and experimental groups from their pretest levels. There was no significant change in eating habits to attain the optimal distribution of calories (see Table 6). This observation was not in agreement with research conducted by Marcus (1986) who recommended 15% protein, 60% carbohydrate, and 25% fat. However, it was in agreement with the research of Story and Resnick (1986) who showed that adolescent athletes did not translate nutrition knowledge into actual dietary behavior.

The experimental group demonstrated a correlation between the Nutrition Knowledge Questionnaire pretest score and carbohydrate intake - the highest positive correlation shown. The highest negative correlation of -.26 was also seen for the experimental group when the nutrition knowledge score was correlated with fat intake. These two correlations demonstrate that the experimental group during the Nutrition Questionnaire pretest and pre-24-hour dietary recall consumed carbohydrates at closer to the optimal level. Although the highest correlation is shown on the pretest, neither score is very predictive of the athletes' dietary habits due to the low correlation.

Table 3. Correlation of Nutrition Knowledge Pretest and Posttest
Scores with Selected Characteristics.

                   Control   Control    Experimental   Experimental
                   Pretest   Posttest   Pretest        Posttest
Characteristics         n = 35                   n = 37

Grade Level        .1635      .1772     -.1099          -.0039

Prior Nutrition
Knowledge         -.2041     -.0260     -.2326          -.0401

Number of
Sports Played     -.0795     -.3040      .1113           .3755

[TABULAR DATA FOR TABLE 4 OMITTED]

Table 5. Mean Percentages of Protein (PRO), Carbohydrate (CHO), and
Fat from total calories in the Precompetition Meal.

                         Pre-24-Hour           Post-24-Hour
                         Recall Recall
                          PRO    CHO    FAT    PRO    CHO    FAT

Control groups

Mean %                      9     47     39    9.5    48.2    41

Experimental groups

Mean %                     13    48.5   39.5    12     51     34

[TABULAR DATA FOR TABLE 6 OMITTED]

DISCUSSION

The results of this study are in agreement with those of many previous studies reviewed (Barr 1987; Story & Resnick, 1986; Perron & Engres, 1985). Athletes in the present study demonstrated a higher level of knowledge after nutrition education, which was not in agreement with the finding of Barr (1987) that the knowledge did not lend itself to improvement of dietary intake, as also noted by Perron and Endres (1985) and Story and Resnick (1986).

Only 26% of the 72 subjects had received nutrition education in the classroom, and the average pretest score noted nutrient intakes to be inadequate among most subjects. The 24-hour dietary recall showed that most athletes ate unbalanced meals. A desire to lose weight was indicated by 76% of the subjects, which is in agreement with studies done by Knudsen, Nowak, and Schultz (1988), who stated that athletic females appear to be more concerned with weight control than energy demands of their sport. These observations were similar to those of Benson, Gilien, and Bourdet (1986), who found nutrition knowledge to be lower among athletes. Further, Skinner et al. (1985) and McDonald, Wearring, and Moase, (1983) reported higher than optimal fat intake with low carbohydrate intake resulting in imbalanced meals. The females who had diets with the most inadequacies were heavier and tended to skip meals. The authors did not show the positive correlation between number of sports played and nutrition knowledge as was noted by Douglas and Douglas (1984). This may be due to the limited sample size. Many athletes in the present study believed a sports drink to be more beneficial than water for rehydration, as was also found by Pratt and Walberg (1988).

Parr, Porter, and Hodgson, (1984) found a similar percentage (46%) of high school athletes taking vitamin supplements as was the case in this study (43%). The importance of healthful food choices to optimize growth, fitness, and athletic performance cannot be underestimated by both participants and professionals. Therefore, there is an immediate need for sports nutrition education applicable to adolescents, especially female athletes. Coaches and dietitians, particularly those who specialize in sports nutrition and exercise physiology, can assist these athletes in achieving peak performance level without compromising growth and development.

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