Is It Really Worth the Effort? Examining the Effects of Mental Fatigue on Physical Activity Effort Discounting.

Physical activity (PA) guidelines are informed by epidemiological evidence but do not account for people's motivation for exerting physical effort. Previous research has shown that people are less motivated to engage in moderate- to vigorous-intensity PA when fatigued. In a two-study series, we investigated how intensity and duration affected people's willingness to engage in PA using an effort-discounting paradigm. A secondary purpose was to examine whether effort discounting was affected by mental fatigue. Both studies revealed a significant Intensity × Duration interaction demonstrating a reduced willingness to engage in PA of higher intensities across increasing duration levels. Study 1 demonstrated greater effort discounting for vigorous-intensity PA with increasing mental fatigue; however, this effect was not observed in Study 2. Findings provide novel insight toward people's motivation for engaging in PA based on the properties of the task, and some evidence suggesting feelings of fatigue may also influence motivation to exert physical effort.

Methods and design for the ADAPT study: Application of integrateD Approaches to understanding Physical activity during the Transition to emerging adulthood.

BACKGROUND: The overarching objective of the study is to obtain a comprehensive understanding of the salient factors predicting changes in physical activity (PA) during adolescents' transition into emerging adulthood. Using the Multi-Process Action Control model as our guiding framework, we will examine how implicit and explicit psychological processes along with regulatory practices impact PA change during this major life transition. Additionally, we will use a real-time data capture method called Ecological Momentary Assessment to further investigate how environmental and contextual factors, and momentary psychosocial influences effect PA patterns across this dynamic life stage. METHODS: The ADAPT study is a 4-year project comprised of two interrelated studies. Study I is a large prospective cohort study that will invite all grade 11 students across one large school board (a total of seven secondary schools) to participate by completing an online questionnaire. Using a cluster randomization approach, a subset of students from each school will be invited to participate in Study II, whereby participants will wear an accelerometer and complete Ecological Momentary Assessments 5 times a day over a 7-day study period. For both studies, following baseline assessments, there will be three annual follow-up assessments approximately 12 months apart. DISCUSSION: The current study represents one of the largest longitudinal cohort studies examining PA and its determinants and associated consequences among adolescents transitioning out of high school into emerging adulthood. Findings from this study will provide a much more in-depth understanding of how and why changes in PA behaviour occur across this first major life transition.

Effects of Peer Encouragement on Efficacy Perceptions and Physical Performance in Children.

Social interactions are theorized to inform relation-inferred self-efficacy (RISE), which, in turn, may influence self-efficacy and behavior. This study investigated the effects of peer encouragement on RISE, task self-efficacy, and physical performance. Children (N = 84) were assigned to dyads and randomized to provide peer encouragement to one another or not (control group). Participants completed two endurance handgrip trials, separated by a cognitively demanding task intended to induce mental fatigue and increase the salience of the peer encouragement manipulation. Participants in the experimental group exchanged words of encouragement prior to the second endurance trial, whereas those in the control group did not. The peer encouragement group reported higher RISE and showed increased performance across trials compared with controls. Providing peer encouragement prior to a challenging physical task was associated with more positive RISE perceptions and improved physical performance.

Effects of Mental Fatigue on Exercise Intentions and Behavior.

BACKGROUND: Exerting cognitive control results in mental fatigue, which is associated with impaired performance during physical endurance tasks. However, there has been little research on the effects of mental fatigue on people's perceptions or behaviors involving lifestyle or recreational exercise. PURPOSE: The purpose of this study was to examine the effect of mental fatigue on intended physical exertion and exercise performance reflective of current physical activity guidelines. METHODS: Using a counterbalanced design, participants completed two 50-min experimental manipulations (high vs. low cognitive control exertion) before exercising at a self-selected intensity for 30 min. At visit 1, participants performed a graded exercise task to gain familiarity with a range of exercise intensities and rating of perceived exertion (RPE) while exercising. At visits 2 and 3, participants rated their intended RPE for the exercise session, performed the experimental manipulations, re-rated their intended RPE, and then completed 30-min of exercise on a cycle ergometer. Total work performed while exercising was recorded for each session. RESULTS: Compared with the low cognitive control condition, the high cognitive control manipulation resulted in significantly greater mental fatigue (d = .73), significantly greater reductions in intended RPE (mean difference = -0.62), and significantly less total work (-12.7 kJ) performed during the exercise session. CONCLUSIONS: Mental fatigue alters the amount of physical effort people are willing to invest in an exercise workout and follow through with those intentions by doing less work. These are the first results showing people may deliberately adjust their physical effort to cope with mental fatigue.

Can behavioral strategies increase physical activity and influence depressive symptoms and quality of life among children with epilepsy? Results of a randomized controlled trial.

PURPOSE: This study examined whether increasing physical activity (PA) through 6 months of behavioral counseling positively influenced depressive symptoms and quality of life (QoL) over 12 months among children with epilepsy (CWE). METHODS: A longitudinal multisite randomized controlled trial (RCT) was conducted with 8-14-year-old children with active epilepsy. Participants wore a pedometer to track daily PA and completed 3 measures at 4 time points to examine depressive symptoms and QoL. Stratified by site and activity level, participants were randomized to an intervention or control group. The 6-month intervention included 11 behavioral counseling sessions targeting self-regulation of PA. To assess the associations among PA, depression scores, and QoL, primary analysis involved mixed-effects models. RESULTS: We recruited 122 CWE, of whom 115 were randomized (Mage = 11 ±â€¯2; 50% female) and included in the analysis. The intervention did not increase PA in the treatment compared with the control group. No differences were found between groups over time during the subsequent 6 months, where PA decreased among all participants. Results did not show differences between the groups and over time for measures of depressive symptoms and QoL. SIGNIFICANCE: The intervention did not improve or sustain PA levels over 12 months. Both groups demonstrated declines in PA over one year, but there were no changes in depression scores or QoL. As most participants were already nearly reaching the Canadian average of step counts of children their age, with a baseline daily step count of over 9000, there may be a challenge for further increasing PA over a longer period.

Cognitive control exertion leads to reductions in peak power output and [Formula: see text] as well as increased perceived exertion on a graded exercise test to exhaustion.

We investigated effects of a brief (10.5 min) cognitively demanding task on graded exercise test performance. Untrained, university students (N = 15) completed two graded exercise tests in counterbalanced, randomised order. One test was preceded by restful viewing of a documentary video (control); the other by a stop-signal task. Cardiorespiratory functions and perceived exertion were monitored during exercise. Peak power output (W) was lower following the stop-signal task (M = 240.03, SD = 53.37) compared to control (M = 246.03, SD = 52.60), P = 0.002, ηP2 = 0.493, as was [Formula: see text] (P = 0.042, Cohen's d = 0.55). Perceived exertion was significantly higher at 50% (d = 0.77) and 75% (d = 0.83) of iso-time following the cognitive task (Ps ≤ 0.01). Results are consistent with research showing negative carryover effects of cognitively demanding tasks on whole-body endurance performance. Results also support the psychobiological model of exercise as performance of the cognitive task did not affect perceived exertion when exercise task demands were lower, but lead to greater perceived exertion and earlier withdrawal of effort at higher levels of exercise task demand. Findings have implications for understanding psychological determinants of exercise performance and conditions that may lead to underestimation of [Formula: see text].

Effects of Mental Fatigue on Physical Endurance Performance and Muscle Activation Are Attenuated by Monetary Incentives.

Physical performance is impaired following cognitive control exertion. Incentives can ameliorate adverse carryover effects of cognitive control exertion but have not been investigated for physical endurance. This study examined the effect of monetary incentives on physical performance and muscle activation following exposure to a mentally fatiguing, cognitive control task. Participants (N = 82) performed two isometric endurance handgrip trials separated by a 12-min cognitive control manipulation using a 2 (high cognitive control [HCC]/low cognitive control [LCC]) × 2 (incentive/no incentive) design. Mental fatigue was significantly higher in the HCC conditions. Performance decreased in the HCC/no incentive condition but was unaffected in the HCC/incentive condition, which did not differ from the low cognitive control conditions. Electromyography data revealed increased muscle activation in the HCC/no incentive condition, which was also attenuated in the HCC/incentive condition. Findings show that incentives counteract the negative effects of HCC on physical endurance and alter central drive to motor units.

Effects of autonomous motivational priming on motivation and affective responses towards high-intensity interval training.

This study examined the effect of autonomous motivational priming on motivation, attitudes and intentions towards high-intensity interval training (HIT). Participants (N = 42) performed a graded exercise test to determine their peak aerobic power (WPEAK). At a subsequent testing session, participants were randomised to complete either an autonomous or neutral motivational priming task followed by a 10 × 1 HIT exercise protocol, alternating 1-min bouts of hard (70% WPEAK) and light (12.5% WPEAK) exercises for 20 min. Participants primed with autonomous motivation reported greater enjoyment, P = .009, ηp(2) = .16, and perceived competence, P = .005, ηp(2) = .18, post-exercise compared to those in the neutral priming condition. Participants in the autonomous motivational priming condition also reported more positive attitudes, P = .014, ηp(2) = .14, towards HIT; however, there was no difference between the conditions for task motivation during HIT or intentions, P = .53, ηp(2) = .01, to engage in HIT. These findings highlight autonomous motivational priming as a method of enhancing affective and motivational experiences regarding HIT.

Self-control training leads to enhanced cardiovascular exercise performance.

The purpose of the study was to investigate the effects of two weeks of self-control strength training on maximum cardiovascular exercise performance. Forty-one participants completed a cognitive self-control depletion task (Stroop task) followed by a maximal graded cycling test and were randomized to training (maximal endurance contractions of spring handgrip trainers, twice daily) or no-treatment control groups. At follow-up (2 weeks), half of each group completed either a time-matched or trial-matched Stroop task followed by another maximal graded cycling test. Results showed a significant 2-way (training X time) interaction (P < 0.001), and a trend for the 3-way (training X time X cognitive task) interaction (P = 0.07). Decomposition of the interactions revealed that across sessions cycling performance increased in both training groups, did not change in the trial-matched cognitive task control group, and declined in the time-matched control group. We conclude that isometric handgrip training leads to self-control strength adaptations that enhance maximal cardiovascular exercise performance or tolerance of exercise at maximal levels of effort.

Isometric exercise and cognitive function: an investigation of acute dose-response effects during submaximal fatiguing contractions.

The purpose of this study was to explore the dose-response relationship between exercise and cognitive performance using an acute bout of isometric exercise. University students (N = 55) were randomly assigned to control, 30%, 50% and 70% of maximum voluntary handgrip contraction groups. Participants performed a modified Stroop task before and after completion of an isometric handgrip endurance trial at their assigned exercise intensity. Ratings of perceived exertion (RPE) and forearm muscle activation (EMG) showed linear trends of progressively greater RPE and muscle activation at greater exercise intensity levels. Regression analysis showed significant (P < .05) linear degradations in frequency of errors on the Stroop task with increasing exercise intensity. We conclude that performing isometric exercise until exhaustion is associated with reduced cognitive performance and that higher intensity isometric exercise leads to greater performance impairments in a linear dose-response manner.

Self-Control Strength Depletion Reduces Self-Efficacy and Impairs Exercise Performance.

The purpose of this study was to investigate the role of task self-efficacy as a psychological factor involved in the relationship between self-control depletion and physical endurance. Participants (N = 37) completed two isometric handgrip endurance trials, separated by a Stroop task, which was either congruent (control) or incongruent (causing depletion). Task self-efficacy for the second endurance trial was measured following the Stroop task. Participants in the depletion condition reported lower task self-efficacy and showed a greater reduction in performance on the second endurance trial when compared with controls. Task self-efficacy also mediated the relationship between self-control depletion and endurance performance. The results of this study provide evidence that task self-efficacy is negatively affected following self-control depletion. We recommend that task self-efficacy be further investigated as a psychological factor accounting for the negative change in self-control performance of physical endurance and sport tasks following self-control strength depletion.

Sources of self-efficacy and coach/instructor behaviors underlying relation-inferred self-efficacy (RISE) in recreational youth sport.

Interpersonal feedback from coaches may be instrumental in the formation of children's self-efficacy to learn or perform sport skills. We report on two studies that explored perceived sources of self-efficacy and relation-inferred self-efficacy (RISE) in one-on-one interviews with sport camp participants (N = 61; ages 7-12) and focus groups with recreational league participants (N = 28; ages 8-12). Participants' responses indicated that prior experiences and socially constructed interactions contributed to the development of self-efficacy and RISE beliefs. Results support Bandura's (1997) theorizing that self-efficacy is developed through processing of experiential feedback as well as Lent and Lopez's (2002) tripartite theory proposing interpersonal feedback from influential others contributes to children's RISE and self-efficacy.

The effects of depleted self-control strength on skill-based task performance.

The purpose of this study was to examine the effects of depleted self-control strength on skill-based sports task performance. Sixty-two participants completed the following: a baseline dart-tossing task (20 tosses), with measures of accuracy, reaction time, and myoelectrical activity of the arms taken throughout; a self-control depletion (experimental) or a nondepletion (control) manipulation; and a second round of dart tossing. As hypothesized, participants in the experimental condition had poorer mean accuracy at Round 2 than control condition participants, and a significant decline in accuracy from Round 1 to Round 2. Experimental condition participants also demonstrated poorer consistency in accuracy compared with control condition participants at Round 2 and a significant deterioration in consistency from Round 1 to Round 2. In addition, consistency in reaction time improved significantly for the control group but not for the experimental group. The results of this study provide evidence that ego depletion effects occur in the performance of a skill-based sports task.

Investigating real-time physical activity behavior using ecological momentary assessment: Effects of mental fatigue and benefit-cost valuations.

BACKGROUND: Current research investigating the relationship between mental fatigue and physical activity behaviors relies on laboratory-based, experimental studies which lack ecological validity. OBJECTIVE: This study used ecological momentary assessment (EMA) to assess feelings of mental fatigue and subjective evaluations (benefits and costs) as predictors of moderate-to-vigorous intensity physical activity in the everyday lives of young adults. METHODS: One hundred participants (n = 22 males, n = 78 females, Mage = 20.60 years, 70% meeting or exceeding physical activity guidelines) responded to digital survey prompts up to four times a day and wore an accelerometer for seven consecutive days. Moderate-to-vigorous intensity physical activity in the 180-min time window following each survey prompt was recorded. Data from the 28 survey-moderate-to-vigorous intensity physical activity epochs were analyzed using multilevel mixed-effects linear modelling. RESULTS: Higher levels of mental fatigue than one's average level were associated with engaging in fewer moderate-to-vigorous intensity physical activity minutes (p = .004) and lower benefit vs. cost scores (p = .001). Higher benefit vs. cost scores than one's average level were associated with engaging in more minutes of moderate-to-vigorous intensity physical activity (p < .001). CONCLUSIONS: Results are the first to demonstrate outside the lab, that mental fatigue experienced in everyday life may amplify the perceived costs of moderate-to-vigorous intensity physical activity, with both factors playing a potential role in moderate-to-vigorous intensity physical activity decision-making. Future research may apply insights gained from this study in design and testing of real-time interventions promoting moderate-to-vigorous intensity physical activity.

Physical Activity Trajectories in Early Childhood: Investigating Personal, Environmental, and Participation Factors.

INTRODUCTION/PURPOSE: To determine personal, environmental, and participation factors that predict children's physical activity (PA) trajectories from preschool through to school years. METHODS: Two hundred seventy-nine children (4.5 ± 0.9 yr, 52% boys) were included in this study. Physical activity was collected via accelerometry at six different timepoints over 6.3 ± 0.6 yr. Time-stable variables were collected at baseline and included child's sex and ethnicity. Time-dependent variables were collected at six timepoints (age, years) and included household income (CAD), parental total PA, parental influence on PA, and parent-reported child's quality of life, child's sleep, and child's amount of weekend outdoor PA. Group-based trajectory modeling was applied to identify trajectories of moderate-to-vigorous PA (MVPA) and total PA (TPA). Multivariable regression analysis identified personal, environmental, and participation factors associated with trajectory membership. RESULTS: Three trajectories were identified for each of MVPA and TPA. Group 3 in MVPA and TPA expressed the most PA over time, with increased activity from timepoints 1 to 3, and then declining from timepoints 4 to 6. For the group 3 MVPA trajectory, male sex (ß estimate, 3.437; P = 0.001) and quality of life (ß estimate, 0.513; P < 0.001) were the only significant correlates for group membership. For the group 3 TPA trajectory, male sex (ß estimate, 1.970; P = 0.035), greater household income (ß estimate, 94.615; P < 0.001), and greater parental total PA (ß estimate, 0.574; P = 0.023) increased the probability of belonging to this trajectory group. CONCLUSIONS: These findings suggest a need for interventions and public health campaigns to increase opportunities for PA engagement in girls starting in the early years. Policies and programs to address financial inequities, positive parental modeling, and improving quality of life are also warranted.

Predictors of leisure time physical activity among people with spinal cord injury.

BACKGROUND: Most studies of physical activity predictors in people with disability have lacked a guiding theoretical framework. Identifying theory-based predictors is important for developing activity-enhancing strategies. PURPOSE: To use the World Health Organization's International Classification of Functioning, Disability and Health (ICF) framework to identify predictors of leisure time physical activity among people with spinal cord injury (SCI). METHODS: Six hundred ninety-five persons with SCI (M age=47; 76% male) completed measures of Body Functions and Structures, Activities and Participation, Personal Factors, and Environmental Factors at baseline and 6-months. Activity was measured at 6 and 18 months. Logistic and linear regression models were computed to prospectively examine predictors of activity status and activity minutes per day. RESULTS: Models explained 19%-25% of variance in leisure time physical activity. Activities and Participation and Personal Factors were the strongest, most consistent predictors. CONCLUSIONS: The ICF framework shows promise for identifying and conceptualizing predictors of leisure time physical activity in persons with disability.

Gender, perceived competence and the enjoyment of physical education in children: a longitudinal examination.

BACKGROUND: The current study examined associations between gender, perceived athletic competence, and enjoyment of physical education (PE) class over time in a cohort of children enrolled in grade four (ages 9 or 10) at baseline (n = 2262). METHODS: We assessed each student 5 times over a period of 2 years. We used mixed effects modeling to examine change over time in enjoyment of PE. RESULTS: Enjoyment of PE declined among girls but remained constant among boys. Higher levels of perceived competence were associated with higher PE enjoyment. A 3-way interaction between gender, competence, and time revealed that PE enjoyment was lowest and declined most markedly among girls with low perceived athletic competence. Among boys with low competence, enjoyment remained at a consistently low level. CONCLUSIONS: Our results indicate that lower perceived athletic competence is associated with low enjoyment of PE, and, among girls, with declining enjoyment. Findings suggest that interventions in a PE context that target perceived competence should be considered in future work.

The health outcomes and physical activity in preschoolers (HOPP) study: rationale and design.

BACKGROUND: The early years are the period of growth for which we know the least about the impact of physical activity. In contrast, we know that more than 90 % of school-aged Canadian children, for example, are not meeting physical activity recommendations. Such an activity crisis is a major contributor to recent trends in childhood obesity, to which preschoolers are not immune. The World Health Organization estimated that more than 42 million children under the age of 5 years were overweight world-wide in 2010. If an activity crisis exists during the preschool years, we should also be concerned about its broader impact on health. Unfortunately, the relationship between physical activity and health during the early years is poorly understood. The goal of the Health Outcomes and Physical activity in Preschoolers (HOPP) study is to describe how the prevalence and patterns of physical activity in preschoolers are associated with indices of health. METHODS: The HOPP study is a prospective cohort study. We aim to recruit 400 3- to 5-year-old children (equal number of boys and girls) and test them once per year for 3 years. Each annual assessment involves 2 laboratory visits and 7 consecutive days of physical activity monitoring with protocols developed in our pilot work. At visit 1, we assess body composition, aerobic fitness, short-term muscle power, motor skills, and have the parents complete a series of questionnaires related to their child's physical activity, health-related quality of life and general behaviour. Over 7 consecutive days each child wears an accelerometer on his/her waist to objectively monitor physical activity. The accelerometer is programmed to record movement every 3 s, which is needed to accurately capture the intensity of physical activity. At visit 2, we assess vascular structure and function using ultrasound. To assess the associations between physical activity and health outcomes, our primary analysis will involve mixed-effects models for longitudinal analyses. DISCUSSION: The HOPP study addresses a significant gap in health research and our findings will hold the potential to shape public health policy for active living during the early years.

Understanding Changes in Adolescent Physical Activity Behaviors and Cognitions Prior to and During the COVID-19 Pandemic.

Despite accumulating evidence that has found significant negative declines in physical activity (PA) as a result of the COVID-19 pandemic, little work has sought to understand how PA cognitions have changed during this period and in relation to behavior change during the pandemic. The purpose of the current study was to investigate the changes in adolescents' PA behaviors and cognitions associated with COVID-19 and prospective predictors of PA using the Multi-Process Action Control (M-PAC) framework. Adolescents were recruited from a large school board and a total of 588 participants (Mage = 15.87 ± 0.43 years, 60% female) completed data collection in both Fall 2019 and 2020-prior to and during the COVID-19 pandemic. Participants completed self-reported measures of moderate-to-vigorous PA (MVPA), participation in organized activities, and variables derived from the M-PAC framework. Mixed effects models were computed to examine longitudinal changes in MVPA and cognitions as well as whether cognitions prior to COVID-19 predict MVPA during COVID-19. A generalized estimating equations model was computed to examine longitudinal changes for participation in organized activities. Findings indicated that MVPA (B = -56.41, p < 0.01) and participation in organized activities (OR = 0.33, p < 0.01) significantly decreased during the COVID-19 pandemic. Correspondingly, there were significant decreases in intentions (B = -0.34), identity (B = -0.19), and habit (B = -0.20), though there were increases in behavioral regulation (B = 0.18). No significant changes were found in affective attitudes, instrumental attitudes, perceived opportunity, and perceived capability. Among the baseline M-PAC cognitions, habit (B = 46.28) was the lone significant predictor of MVPA during COVID-19. Overall results suggest that adolescents' PA behaviors and cognitions were negatively impacted by the COVID-19 pandemic, along with promising evidence that restrictions prompted adaptive utilization of behavioral regulation skills. Moreover, habit appears to play a salient role in predicting PA behaviors during uncertain times involving major life disruptions. These findings highlight the need to dedicate additional attention to PA promotion as COVID-19 moves toward an endemic phase, and that interventions targeting habit formation may be critical for helping adolescents better sustain healthy active lifestyles during major life changes.

Preschool to School-Age Physical Activity Trajectories and School-Age Physical Literacy: A Longitudinal Analysis.

PURPOSE: The associations between longitudinal physical activity (PA) patterns across childhood and physical literacy have not been studied. The purpose of this study was to identify PA trajectories from preschool to school-age, and to determine if trajectory group membership was associated with school-age physical literacy. METHODS: Participants (n = 279, 4.5 [0.9] y old, 48% girls) enrolled in this study and completed annual assessments of PA with accelerometry over 6 timepoints. Physical literacy was assessed at timepoint 6 (10.8 [1.0] y old). Group-based trajectory analysis was applied to identify trajectories of total volume of PA and of moderate to vigorous PA and to estimate group differences in physical literacy. RESULTS: Three trajectories of total volume of PA and of moderate to vigorous PA were identified. Groups 1 (lowest PA) included 40% to 53% of the sample, groups 2 included 39% to 44% of the sample, and groups 3 (highest PA) included 8% to 16% of the sample. All trajectories declined from timepoint 1 to timepoint 6. School-age physical literacy was lowest in trajectory groups with the lowest total volume of PA or moderate to vigorous PA over time (P < .05). CONCLUSIONS: PA should be promoted across early and middle childhood, as it may play a formative role in the development of school-age physical literacy.