Effect of a Personal Health and Fitness Course on Dietary Intake, Physical Fitness and Attitudes toward Wellness among College Students

A nonrandomized three-group pretest-posttest quasi-experimental design with a no-intervention control (Control) and two intervention groups (Class 1, Class 2) was implemented to address the hypotheses of the study. All subjects provided written informed consent using an approved paper and pencil consent form (IRB# HR-2434) prior to any data being collected. Data were collected from Class 1 and Control subjects at the beginning and end of a 15-week Fall Semester with data collected from Class 2 subjects at the beginning and end of the following 15-week Fall semester during the following calendar year. Subjects self-selected their group assignment and neither the subjects nor the data collectors were blind to the group assignments.
 

Three groups of students were recruited to participate in this study. The subjects in the two experimental groups (Class 1 and Class 2) were recruited from the students enrolled in a general education course open to only undergraduate students titled Personal Health and Fitness (HEAL 1931). All but one student in these two courses consented to be involved in the study. Students enrolled in this course were recruited to participate in the study during two successive academic years since the course was only offered during Fall semester. During the first class session of the Personal Health and Fitness course a brief presentation of the study was made by a member of the research team. Students in this course who were interested in participating in the study were encouraged to call a member of the research team to discuss the study and schedule an appointment to provide informed consent. The Control group was recruited during the same fall semester that subjects were recruited for the Class 1 group. Control subjects were recruited from the general undergraduate student body by placing recruitment fliers in campus dormitories. The flier encouraged undergraduate students to call a member of the research team to discuss the study and if they wished to participate, schedule an appointment to provide informed consent and complete baseline data collection. Inclusion criteria were the subjects be 18-22 years of age, enrolled in full time study and able to complete all of the data collection protocols. Subjects were excluded from the study if they reported any health conditions which prohibited vigorous physical activity according the American College of Sports Medicine [18] or provided a positive response to any item on the Physical Activity Readiness Questionnaire (PAR-Q) [19].
 

During the Fall Semester when subjects were recruited into the study they completed data collection at the beginning and end of the 15-week fall semester. Demographic data were collected at the beginning of the semester only, while all other data were collected at both the beginning and the end of the semester. The same Graduate Research Assistants (GRAs) collected data from Control subjects while the Group 1 and Group 2 subject’s data collection was conducted by the Fitness Intern (FI) they were assigned to as part of the course requirements during the semester. The GRAs and the FIs were upper division or graduate students enrolled in the Exercise Physiology program and had completed courses in fitness and nutrition assessment that included the data collection protocols.

Demographic data collected were collected through self-report using a paper and pencil questionnaire. Data collected included gender, race, class rank, relationship status, major area of study, age and number of credit hours enrolled.

Attitudes toward a healthy diet and physical activity were measured using two different instruments. Attitudes toward physical activity were assessed using the Physical Activity Belief Scales for Diabetes Risk [20]. This instrument was designed to assess 3 components of attitude toward physical activity which are not specific to diabetes although the instrument was developed among individuals who were at risk for developing diabetes. This paper and pencil scale using a 5-point Likert response scales assessed the subject’s attitude toward physical activity including behavioral belief, normative belief, and control belief with higher scores indicating a more favorable attitude toward physical activity. It was decided to drop the normative belief subscale from the analysis since a number of questions did not apply to the sample including questions about the subject’s spouse or children. These subscales are consistent with the Theory of Planned Behavior (TPB) to predict one’s intention to engage in physical activity. Psychometric analyses provided evidence of construct validity and reliability, internal consistency (a=.76-.95), and test-retest evaluations indicated scale stability (r=.79-.91) [20].

Attitudes toward a healthy diet were collected using a similar paper and pencil instrument titled “Healthful Eating Belief Scales for Persons at Risk of Diabetes” [21]. This instrument using 5-point Likert responses also measured three attitudes toward a healthy diet including behavioral beliefs, normative beliefs, and control beliefs with higher scores indicating a more favorable attitude toward a healthy diet. Again, normative beliefs were not collected as part of this study because the items were not relevant to the sample including questions about the subject’s spouse and children. Psychometric characteristics of these subscales supported the internal consistency of the instrument (Cronbach alphas .80-.84, with acceptable test-retest reliability) [21].

Dietary intake was measured using analysis of a two-day twenty-four hour recall of dietary intake. Participants were interviewed and asked to recall everything they had eaten during the two previous 24-hour periods. These records were then coded into the Food Tracker program on the Choose My Plate website sponsored by the U.S. Department of Agriculture (http://www.choosemyplate.gov/). This program provided an average daily intake of the subject’s total calories, sodium, iron, calcium, fat and percentage of calories from fat. Employing a 24-hour dietary recall has been demonstrated to provide a valid assessment of dietary intake [22].

Physical fitness was assessed by the subjects completing a number of testing protocols to that measured BMI, aerobic fitness, muscular strength, muscular endurance and flexibility using standardized measurement protocols. Aerobic fitness was assessed while the participant completed a 3-minute step test protocol. This protocol required the individual to step up and down on a 12-inch bench at a rate of 24 steps per minute for 3 minutes. A Polar heart rate monitor (Polar Electro, Finland) continuously monitored the heart rate of the participant during the test. Heart rate was recorded throughout the test and for two minutes following completion of the protocol. Aerobic fitness (Vo₂max ml/kg.min) was calculated employing a standard conversion formula using the subject’s heart rate response to the exercise activity [23].

Muscle strength is defined as force generated through muscle fiber contraction. For the purposes of this study a one-repetition maximum lift of bench press and leg press were used to measure muscle strength. The 1-RM leg press assesses the maximum muscular strength of the major muscles of the lower body using a leg press machine. The 1-RM bench press assesses maximum muscular strength of the upper body using a barbell and plate loaded weight. The 1-RM for both of these exercises was determined by a standardized protocol that exhibits acceptable reliability [24].

Muscular endurance was assessed of the upper body, lower body and core using standard protocols [25]. Upper body muscular endurance was assessed by the number of push-ups the individual could perform in 30 seconds. Males completed this assessment position in the standard push-up position prone on their toes and hands with a single repetition involving lowering the body to the floor until their nose touches between their hands and then returning to the starting position. Females completed the same protocol only positioned on their palms and knees. Lower body strength was assessed by the number of sit-to-stand repetitions a subject could do in 30-seconds. Core strength was assessed by measuring the number of bent-knee sit-ups without restraint of their feet the participant could perform in 30-seconds. Finally, flexibility of the upper back, lower back and hamstrings was assessed using the standardized Sit-and-Reach test [26].

The two similar interventions (Class 1 & Class 2) were delivered as a component of a 3-credit hour undergraduate “Personal Health and Fitness” course that was offered during two consecutive fall semesters at a private Midwestern university. The overall objective of this course was, upon successful completion, the students would be able to pursue a healthier lifestyle by making informed decisions regarding their own physical activity and dietary intake. The class content for both Class 1 and Class 2 were identical and included weekly lectures from a variety of disciplines regarding the personal, social, cultural, physical and environmental factors enabling and/or inhibiting students to engage in recommended dietary intake and physical activity (Table 1). In addition to these lectures students were expected to meet weekly with fitness intern (FI) who was an upperclassmen enrolled in Exercise Physiology. These FIs were completing an advanced elective course in Exercise Science designed to increase their practical application of their knowledge, including fitness assessment, cardiovascular and resistance programming, program variable modification, goal setting, and motivation, employing standard American College of Sports Medicine (ACSM) and National Strength and Conditioning Association (NSCA) protocols. During Class 1, (n=20) the subjects met every week with their assigned FI to complete an assigned homework activity. Subjects exposed to the second intervention in Class 2, (n=29) were required to meet with their assigned FI once per week to complete the same homework assignments as those completed by Class 1 subjects and to engage in at least 30 minutes of physical activity with their FI per week. The content was designed to improve the dietary intake and physical activity of the subjects in both intervention groups. Control subjects (n=24) who volunteered for the study were not registered for “Personal Health and Fitness” and had no access to the course content or contact with the FIs or any member of the research team between the two data collection points.

The content of the two 3-credit hour undergraduate “Personal Health and Fitness” courses was based upon the Theory of Planned Behavior [27]. This theory states that behavioral beliefs, subjective norms and perceived behavioral control shape an individual's intentions and likelihood of engaging in a particular behavior. Behavioral beliefs are individual's beliefs about the consequences, positive or negative, that will result from a particular behavior. Subjective norms are an individual's perceptions about significant others (family, friends, important others) expectations about engaging or not engaging in a particular behavior. Finally, perceived behavioral control includes the individual’s self-efficacy to engage in a particular behavior. The content of the lectures in this course, delivered from a wide variety of disciplines, was designed to favorably change the student’s behavioral beliefs about eating a healthy diet and increasing their physical activity. The homework activity with the FI was designed to favorably impact the subject’s subjective norms regarding their FI’s expectations about their eating a healthy diet and being more physically active. Finally, the homework activity was also designed to increase the subject’s self-efficacy to eat a healthy diet and engage in more physical activity through the FI modeling the desired behavior and the subject engaging in the desired behavior with the FI.
 

Analysis of the data was completed in two phases. In phase one, the demographic data collected at the beginning of the semester only, were compared between the three study groups. The second phase of the analysis involved comparing the three study groups to address the three study hypotheses. Repeated measures ANOVA were calculated to determine the effect of group (Control, Class 1, Class 2), time (Beginning & End of semester) and the interaction of group and time on the outcome variables of attitudes toward diet and physical activity, physical fitness and dietary intake. Significant (p<.05) main or interaction effects were further addressed through calculating Tukey’s least significant different post hoc comparisons to determine differences between group/time means.
 

These findings must also be interpreted cautiously because a number of limitations of the study threaten the validity of the findings. First, measures of BMI and aerobic fitness (VO₂max ml/kg.min) were not responsive to the intervention. These findings could be attributed to the insensitivity of the 3-minute step test to detect changes in aerobic fitness following 14 weeks of training. This insensitivity may also be applied to the measure of BMI which is a gross measure and not sensitive to changes in body composition including fat to lean ratios that may occur without an overall change in body weight and height. Future studies may consider using a more sensitive measure of body composition that quantifies lean and non-lean percentages of total body mass. Secondly, the normative belief subscales for physical activity and eating a healthy diet were found to be inappropriate for the sample. If this variable was measured it may have further described the efficacy of the two interventions. The moderate sample size and the demographic differences between the study groups may have diluted the effect of the intervention. Further, the long-term impact of the intervention beyond the 15-week course was not considered. Finally, the sample was homogenous, drawn from a single college campus and likely doesn’t represent all college undergraduate students.
 

Low levels of physical activity and unhealthy dietary intake during college years are evidenced in the increasing weight gain experienced by undergraduate students. College students are susceptible to trying different lifestyle choices that may include consuming a healthy diet and increased levels of physical activity that result in increased physical fitness. The interventions studied in this trial attempted to operationalize the Theory of Planned Behavior constructs into an academic course designed to facilitate students to increase their physical activity and improve their dietary intake. Both intervention groups exhibited reduced caloric intake and improvements in physical fitness and attitudes toward a healthy dietary intake and physical activity. The intervention (Class 2) that offered the opportunity to engage in physical activity with the FI had the greatest impact on attitudes toward physical activity and measures of physical fitness. The control group did not change on any outcome variables.