Engagement in Physical Exercise as a Behavior Modification: Baseline Phase
Christy L. Lipps
Liberty University
PSYC320: Behavior Modification
Professor Kevin Conner
April 27, 2025
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Engagement in Physical Exercise as a Behavior Modification
Target Behavior
The target behavior for this study is engaging in physical exercise, defined as working out
for at least 30 continuous minutes at Planet Fitness on three separate days of the week. The
physical exercise must include cardio exercises, like running or cycling, and strength training
exercises, like lifting weights. To make sure the workout is effective the participant will aim for a
heart rate of about 120 beats per minute. The participant can also pay attention to their exercise
to see that it reaches a level of moderate to vigorous intensity by subjective indicators such as
increased breathing where conversation is possible but singing becomes challenging (Yu et al.,
2021). This operational definition helps keep everything organized, by ensuring that the behavior
is specific, measurable, and observable, it also allows consistent tracking through both the
baseline and intervention phases. Research shows that the heart rate and how hard the participant
feels they are exercising, as indicated by the talk test (Yu et al., 2021) are good markers of
exercise intensity.
Observation Period and Dimensions
This experiments baseline observation period will be a full week from Monday, April 14th,
2025, to Sunday, April 20th, 2025. The primary dimension used to measure the target behavior
during this phase will be frequency, which is the number of days the participant exercises at least
30 continuous minutes at Planet Fitness, meeting the specified criteria for the week. The duration
(length of each exercise session) and a qualitative measure of intensity (based on heart rate or the
talk-test) will be noted but the primary measure for the baseline graph will be the number of
successful exercise sessions on separate days of the week.
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The observation will occur in a natural environment where the participant will complete
their week, without making any deliberate changes to their exercise related behaviors. The
observation will be unstructured; there will be no requirements or prompts to exercise, and the
participants’ natural exercising behavior will be recorded. The participant will keep a daily log
(either digital or paper) in which she will note if she has or has not done at least 30 continuous
minutes of exercise at Planet Fitness that day. If she did exercise, she will note what she did and
how hard it was.
Results
The baseline observation of the study was conducted over 7 days which was from April
14th, 2025, through April 20th, 2025. The aim was for the participant to reach the frequency of the
target behavior; engaging in at least 30 continuous minutes of physical activity at Planet Fitness
on three separate days of the week. The data collected indicates that the target frequency was not
achieved during the baseline period. There were no times when the participant exercised for 30
minutes at Planet Fitness on any three days of the week. On Tuesday, April 15th, 2025, the
participant recorded light walking for 25 minutes and on Friday, April 18th, 2025, the participant
recorded weightlifting for 15 minutes, however, neither instance went for 30 continuous minutes.
Therefore, during the seven-day baseline period, the participant exhibited a frequency of zero
successful exercise sessions that met the target behavior definition. The target behavior is absent,
making the target behavior deficit the focus of the upcoming intervention.
Figure 1
Frequency of Target Exercise Behavior During Baseline Phase (April 14th to April 20th, 2025)
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Baseline Observations
The baseline data shows a clear behavioral deficit on the target behavior of regular
sustained exercise at Planet Fitness. During the seven days, there was not one occasion on which
the participant exercised for a minimum of 30 continuous minutes on three separate days. Some
movement took place on Tuesday and Friday but was not of the defined duration of 30
continuous minutes.
This low frequency may have been caused by various possible triggers or environmental
factors. Shifting to become a stay at home mom and online college student, as previously noted,
may have interrupted her previous routines that included more movement. Without a regular
work schedule and commute, people can become more sedentary or inactive at home.
During the baseline week, it was noted that on multiple days, the participant was inactive
for a long duration. No specific stimuli were observed to reliably elicit the desired behavior of
target exercise. The new daily routine does not have exercise in it, which can be a key factor.
The flexibility of the current schedule may be beneficial, but it does not appear to generate the
cues for movement that might be essential to more structured living.
0
5
10
15
20
25
30
4/14/25 4/15/25 4/16/25 4/17/25 4/18/25 4/19/25
Amount of Exercise During Baseline
Minutes Exercised (30 Mins meeting
criteria)
Monday through Sunday (week of April 14, 2025 to April 20, 2025)
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After carefully analyzing the data points, it is noted that the target behavior is consistently
absent which indicates the need for intervention. The partial engagement on Tuesday and Friday
shows a willingness to act, but not enough planning, scheduling, or support to meet duration and
frequency criteria for each day of the week. By collecting baseline data, we obtain a good idea
of the current level of the target behavior that can be used to measure the effectiveness of the
future behavior modification intervention.
References
Yu, M., Corletto, J., & Barkley, L. C. (2021). Exercise prescription. Current Sports Medicine
Reports, 20(12), 627–628. https://doi.org/10.1249/JSR.0000000000000914
