Critical Thinking Skills in a Large Lecture Class Effects of Body Weight and Exercise Level

1. Critical Thinking Skills in a Large Lecture Class Effects of Body Weight and Exercise Level Deborah J. Good and Angela S. Anderson Department of Human Nutrition Foods and Exercise, Virginia Tech ABSTRACT RESULTS There is growing concern about the lack of critical thinking skills (CTS) in college graduates. Using animal models, researchers have found that obesity can impair spatial learning, while intense exercise can improve cognitive ability. In humans, adults with high body mass indexes (BMIs) show impaired performance in decision-making activities, and adolescents with childhood metabolic syndrome show significantly lower math and spelling scores. Conversely, female college students undergoing short-term, intense exercise exhibit increased working memory. In this study, we tested the hypothesis that BMI (negatively) and exercise (positively) influences CTS in college-aged students. To do this we utilized a large lecture class, Metabolic Nutrition 3026 with an enrollment of 234 students (49.1% participation rate) and the iClicker in-class response system. Specific questions were developed which were considered either to use or not to use CTS, and students were asked these questions throughout the semester, without prior knowledge that they might be used in a research study. In addition, students were asked about their exercise and BMI level. Neither BMI nor exercise showed a significant effect on whether students answered CTS-type questions correctly. There were several confounding factors. First, students in this course self-reported high levels of weekly exercise, compared to the average American, with 84/115 (73%) of students reporting exercise of at least 2-3 times per week. In addition, there were reduced numbers of obese individuals in the class, than the general population, with only 2 of the 115 (1.7%) giving their self-reported BMI as obese. Thus, slight differences in CTS score were not found to be significant due to low numbers in the obese, and low exercise groups. The study will be repeated in spring 2013 to add additional participants to the study and with a slight re-design to capture true CTS scores using graded iClicker questions. Figure 3: Effect of Gender on Critical Thinking Ability. There were 90 females and 25 males with no significant differences in correct questions answered with gender as the dependent variable. Figure 4: Effect of BMI on Critical Thinking Ability. BMI categories were grouped based on published ranges, The student population included five underweight students, 101 normal weight students, seven overweight students, and two obese students. There was no significant differences in correct questions answered with BMI as the dependent variable. Figure 5: Effect of Exercise Frequency on Critical Thinking Ability. Exercise frequency was divided into three categories. 31 students exercised once per week or less, 48 students exercised 2-3 times per week, and 36 students exercised 5-7 times per week. There were no significant differences in correct questions answered with exercise frequency as the dependent variable. METHODS • The student population included 115 students made up of 90 females and 25 males. The predominant number of women in the study represents the demographic population in the department of Human Nutrition, Foods and Exercise. Students in Metabolic Nutrition 3026 are juniors and seniors. All students consented to use of their data in this study. • 14 questions were used to assess critical thinking skills from 14 different lectures. Unanswered questions were not included in percentage. • Questions ranged from synthesizing an answer from several facts to interpreting published data (Figure 1) to determine the correct answer. Percentage of correct answers were determined by whether or not the correct answer was selected using the iClicker (Figure 2). • BMI and exercise frequency were self-reported using the iClicker. Those students that did not answer these iClcker questions were excluded from the study. CONCLUSIONS AND FUTURE DIRECTIONS • There were no significant differences found between gender, BMI or exercise level in the percent correct answers in this study. • Confounding variables include the low number of students that were not exercising, and/or obese. • iClicker questions were not graded, and therefore students could randomly choose, so these questions may not be an accurate reflection of critical thinking ability. • The study is being repeated in the spring 2013 Metabolic Nutrition course, with several key changes: • Body weight and height will be asked, rather than BMI to ensure that the BMI is calculated and reported correctly. • The number of minutes per week of exercise, as well as exercise intensity will be asked, rather than number of days/week to ensure an accurate exercise level is reported. • While we had hoped to include graded iClicker questions, problems with connectivity in the room means that we can’t grade students consistently using the system. The syllabus currently only uses iClicker questions for participation grading, not correct answers. Acknowledgements This work was funded by: 2011-2013: Center for Instructional Development and Educational Research (CIDER), Instructional Enhancement Grant, Virginia Tech Figure 1: Example of an iClicker question used in class Figure 2: Example of an iClicker unit from www.iClicker.com)