Effect of Fed State on Self-selected Intensity and Affective Responses to Exercise Following Public Health Recommendations
Int J Exerc Sci
Effect of Fed State on Self-selected Intensity and Affective Responses to Exercise Following Public Health Recommendations
RYAN RHODEWALT 0
BLAQUE SAUR 0
KATELYN LARGENT 0
TODD A. ASTORINO 0
ZACHARY ZENKO 1
MATTHEW M. SCHUBERT 0
0 California State University - San Marcos, Department of Kinesiology , San Marcos, CA USA
1 California State University - Bakersfield, Department of Kinesiology , Bakersfield, CA , USA
International Journal of Exercise Science 12(2): 602-613, 2019. Nutritional status has numerous effects on exercise metabolism and psychological responses. The effect of fed state on changes in affective valence; however, are unknown. Thus, the present study examined how fed state influenced self-selected exercise intensity, affective responses during exercise, and exercise enjoyment when exercise was completed following physical activity guidelines for public health. In a repeated-measures crossover design, 25 recreationally active men and women (age and BMI = 22.0 ? 2.0 yr and 24.3 ? 3.3 kg/m2) performed a single 30 min session of treadmill exercise at a Rating of Perceived Exertion (RPE) equal to 13 on the Borg 6-20 scale following an overnight fast (FAST) or 30 minutes after a small meal (FED). Affective valence was recorded every 3 minutes during exercise. Heart rate and gas exchange data were measured continuously using a metabolic cart, blood glucose and blood lactate concentration were measured pre/post-exercise, and enjoyment was measured 15 minutes post-exercise. There was no effect of condition on affective valence, enjoyment, or self-selected intensity (all p>0.05). However, pre-exercise blood glucose was higher in FED pre-exercise, but higher post-exercise in FAST (p<0.05). Blood lactate concentration was also higher in FAST (p<0.05). Our results reveal minimal effects of a small, high-carbohydrate pre-exercise meal on in-task and post-task affective responses, exercise enjoyment, and self-selected intensity. These data suggest that an overnight fast does not alter affective valence or reduce enjoyment of continuous exercise.
Fed; fasted; exercise; affect; enjoyment
INTRODUCTION
It is evident that obesity rates have increased worldwide, and that obesity is a risk factor for
several chronic diseases (
9, 32, 33
). Much attention has been given to the relationship between
the development of cardiovascular disease (CVD) and modifiable risk factors such as obesity,
diabetes, and physical inactivity (
26
). Furthermore, compelling evidence now exists that
increases in cardiorespiratory fitness can reduce or even eliminate mortality risk of other CVD
risk factors (
18, 25, 27
). In light of current health issues, physical activity is heavily promoted
to ameliorate disease risk. However, existing guidelines suggest anywhere from 150-300
minutes per week of moderate-vigorous physical activity (MVPA)(
19
), which may be a
significant barrier to adherence due to the extensive time commitment, as fewer than 5% of
individuals from a nationally representative sample achieved 30 minutes of activity per day as
assessed via accelerometry (
45
).
Many behavioral interventions operate under various psychological theories (e.g., social
cognitive theory, theory of planned behavior) that posit humans will make decisions rationally
based on the available information (
16
), but if this was the case, clearly more people would
engage in physical activity and adhere to exercise programs, given the overwhelming amount
of data which show the health benefits of MVPA (
14
). Therefore, some experts have expressed
that the hedonic theory of motivation should become the predominant structural theory for
physical activity behavior (
14, 15
). Hedonic theory states that individuals will do what makes
them feel good and will avoid what makes them feel worse. More specifically, in
psychological hedonism, the overlying theory states that behavior is motivated by the desire
for pleasure and avoidance of displeasure, which can occur immediately or in the long term
(
31
) and can be related to sensations (such as pain from an injury) or attitudes and emotions
(pleasure of pride/accomplishment) (
42
). For example, affective responses to an acute exercise
bout predicted physical activity 6 and 12 months later (
47
). These authors? results suggested
that a one unit increase in scores on the Feeling Scale (a single-item measure of the valence
dimension of affect, -5 to +5, very bad to very good, 20) was associated with an additional 38
and 41 minutes of physical activity per week 6 and 12 months later, respectively. These data
are supported by the conclusions of a recent review that found affective responses during
exercise were predictive of exercise behavior; however, post-exercise affective valence (valence
is the positivity or negativity theorized to motivate approach or avoidance of an event or
situation) was not (
36
). Thus, any strategies to improve experienced pleasure expe (...truncated)