A Methodological Checklist for Studies of Pleasure and Enjoyment Responses to High-Intensity Interval Training: Part I. Participants and Measures.

For decades, the exercise psychology research literature echoed the conclusion that exercise makes most people feel better, with no clear evidence that this "feel-better effect" is moderated by intensity. An overhaul of the methodological approach subsequently showed that high-intensity exercise is experienced as unpleasant, and the "feel-better effect," although possible, is conditional and therefore not as robust or prevalent as initially thought. Recently, several studies investigating high-intensity interval training (HIIT) have concluded that HIIT is pleasant and enjoyable, despite the high intensity. Considering that HIIT is emerging as an option in physical activity recommendations and exercise prescription guidelines, in part due to these claims, a methodological checklist is presented to aid researchers, peer reviewers, editors, and other readers in critically appraising studies examining the effects of HIIT on affect and enjoyment. This first part addresses the characteristics and number of participants, as well as the selection of measures of affect and enjoyment.

Negative affect impedes perceptual filling-in in the uniformity illusion.

The notion of cognitive penetrability, i.e., whether perceptual contents can in principle be influenced by non-perceptual factors, has sparked a significant debate over methodological concerns and the correct interpretation of existing findings. In this study, we combined predictive processing models of visual perception and affective states to investigate influences of affective valence on perceptual filling-in in extrafoveal vision. We tested how experimentally induced affect would influence the probability of perceptual filling-in occurring in the uniformity illusion (N = 50). Negative affect led to reduced occurrence rates and increased onset times of visual uniformity. This effect was selectively observed in illusionary trials, requiring perceptual filling-in, and not in control trials, where uniformity was the veridical percept, ruling out biased motor responses or deliberate judgments as confounding variables. This suggests an influential role of affective status on subsequent perceptual processing, specifically on how much weight is ascribed to priors as opposed to sensory evidence.

Current and expected affective valence interact to predict choice in recurrent decisions.

Research on the role of affect in decision-making indicates that both predecisional current and expected affective valence predict choice. However, the exact role of current and expected affect for recurrent decision-making is still a matter of debate. We used a generalised mixed effect model to predict gambling responses in an experience-based learning task from ratings of current and expected affective valence. Results indicate that current and expected affective valence interact to predict choice. While expected valence had the biggest effect size, current valence and the interaction still contributed significantly to the prediction of choice. Resolving the interaction showed that participants relied more on the current valence if expectations were unclear or positive. These findings are discussed in the context of dual-process accounts and the affective signalling hypothesis. In conclusion, current and expected valence depend on one another and interact to predict choice in recurrent decision tasks.

High-intensity interval training elicits more enjoyment and positive affective valence than moderate-intensity training over a 12-week intervention in overweight young women.

Background: The purpose of this study was to compare the differences in enjoyment and affect in response to four weight control intervention protocols over 12 weeks. Methods: Sixty overweight young females were randomised into four intervention groups: repeated sprint training (RST, 6-sec all-out sprint interspersed with 9-sec rest), high-intensity interval training (HIIT) with short interval (HIIT120, 1-min effort at 120% V̇O2peak) and long interval (HIIT90, 4-min effort at 90% V̇O2peak), and moderate-intensity continuous training (MICT, 60% V̇O2peak) by cycling over 12 weeks. The total workload in each training session in HIIT120, HIIT90, and MICT was confined to 200 kJ, while it was lower in RST with 57 ± 4 kJ. Enjoyment (Physical Activity Enjoyment Scale, PACES) and affective valence (Feeling Scale, FS) were measured throughout the intervention. Results: The score of the PACES on average over 12 weeks showed a significant between-group effect that was lower in MICT (80.8 ± 11.8) compared with HIIT120 (92.5 ± 11.4) and HIIT90 (96.8 ± 13.9) (p < 0.05). In the 8th week, enjoyment was scored higher in two HIITs compared with MICT. In the 12th week, HIITs and RST were more enjoyable than MICT, where two HIITs were better than RST. The score of FS showed a significant between-group effect that was higher in HIIT90 (1.5 ± 1.4) compared with HIIT120 (0.2 ± 1.2) (p < 0.05), but a non-significant time or group-by-time interaction effect. A significant weight loss occurred in three interval training protocols (p < 0.05), but not in MICT. The V̇O2peak significantly increased in four groups without between-group difference. Conclusion: Interval training, especially the long-interval type, is an enjoyable and pleasant long-term exercise intervention for overweight young women. RST could be an alternative for weight control considering its time efficiency with comparable enjoyment and overall pleasure.

When It HIITs, You Feel No Pain: Psychological and Psychophysiological Effects of Respite-Active Music in High-Intensity Interval Training.

The authors investigated the effects of respite-active music (i.e., music used for active recovery in between high-intensity exercise bouts) on psychological and psychophysiological outcomes. Participants (N = 24) made four laboratory visits for a habituation, medium- and fast-tempo music conditions, and a no-music control. A high-intensity interval-training protocol comprising 8 × 60-s exercise bouts at 100% Wmax with 90-s active recovery was administered. Measures were taken at the end of exercise bouts and recovery periods (rating of perceived exertion [RPE], state attention, and core affect) and then upon cessation of the protocol (enjoyment and remembered pleasure). Heart rate was measured throughout. Medium-tempo music enhanced affective valence during exercise and recovery, while both music conditions increased dissociation (only during recovery), enjoyment, and remembered pleasure relative to control. Medium-tempo music lowered RPE relative to control, but the heart rate results were inconclusive. As predicted, medium-tempo music, in particular, had a meaningful effect on a range of psychological outcomes.

The impact of five nights of sleep restriction on emotional reactivity.

An inadequate amount of sleep can negatively affect emotional processing, causing behavioural and neurofunctional changes. However, unlike the condition of total sleep deprivation, which has been extensively studied, the effects of prolonged sleep restriction have received less attention. In this study, we evaluated, for the first time, the effects of five nights of sleep restriction (5 hr a night) on emotional reactivity in healthy subjects. Forty-two subjects were selected to participate, over two consecutive weeks, in two experimental conditions in counterbalanced order. The subjects were tested the morning after five nights of regular sleep and after five consecutive nights of sleep restriction. During the test, participants evaluated valence and arousal of 90 images selected from the International Affective Picture System. The subjects perceived pleasant and neutral pictures in a more negative way in the sleep-restriction condition compared to the sleep condition. This effect survived after removing the contribution of mood changes. In contrast, there was no significant difference between conditions for ratings of unpleasant pictures. These results provide the first evidence that an inadequate amount of sleep for five consecutive nights determines an alteration of the evaluation of pleasant and neutral stimuli, imposing a negative emotional bias. Considering the pervasiveness of insufficient sleep in modern society, our results have potential implications for daily life, as well as in clinical settings.

Effects of three low-volume, high-intensity exercise conditions on affective valence.

A common barrier to exercise is "lack of time". Accordingly, interest in low-volume, high-intensity training has grown exponentially since this activity is considered time-efficient. However, the high-intensity nature of this exercise may frequently result in feelings of displeasure creating another barrier for many people. The purpose of this study was to compare affective (pleasure-displeasure) responses to three low-volume, high-intensity exercise conditions, including a novel shortened-sprint protocol. Using a within-subjects, randomised crossover experiment, healthy participants (N = 36) undertook a single bout of: 1) traditional reduced-exertion, high-intensity interval training (TREHIT), 2) a novel, shortened-sprint REHIT (SSREHIT) protocol, and 3) sprint continuous training (SCT). Affect and perceived efforts were recorded throughout exercise using the Feeling Scale (FS) and the 15-point Borg Rating of Perceived Exertion (RPE) scale, respectively. Enjoyment was recorded 5 min post-exercise using the Exercise Enjoyment Scale (EES). Differences were found for FS (condition by time interaction: P = 0.01GG, η2 = 0.26), RPE (P = 0.01GG, η2 = 0.23), and enjoyment (P < 0.01) with all outcomes favouring SSREHIT. Shortened-sprint protocols may diminish feelings of displeasure and might be a time-efficient yet tolerable exercise choice to help motivate some people to increase their physical activity and fitness.

Brain and Body Emotional Responses: Multimodal Approximation for Valence Classification.

In order to develop more precise and functional affective applications, it is necessary to achieve a balance between the psychology and the engineering applied to emotions. Signals from the central and peripheral nervous systems have been used for emotion recognition purposes, however, their operation and the relationship between them remains unknown. In this context, in the present work, we have tried to approach the study of the psychobiology of both systems in order to generate a computational model for the recognition of emotions in the dimension of valence. To this end, the electroencephalography (EEG) signal, electrocardiography (ECG) signal and skin temperature of 24 subjects have been studied. Each methodology has been evaluated individually, finding characteristic patterns of positive and negative emotions in each of them. After feature selection of each methodology, the results of the classification showed that, although the classification of emotions is possible at both central and peripheral levels, the multimodal approach did not improve the results obtained through the EEG alone. In addition, differences have been observed between cerebral and peripheral responses in the processing of emotions by separating the sample by sex; though, the differences between men and women were only notable at the peripheral nervous system level.

Perceptual and Cardiorespiratory Responses to High-Intensity Interval Exercise in Adolescents: Does Work Intensity Matter?

High-intensity interval exercise (HIIE) may not elicit prominent unpleasant feelings even with elevated perceived exertion and physiological stress in adolescents. However, the influence of different HIIE work intensities on the affective experience and cardiorespiratory responses is unknown. This study examined the acute affective, enjoyment, perceived exertion and cardiorespiratory responses to HIIE with different work intensities in adolescents. Participants (n = 16; 8 boys; age 12.0 ± 0.3 years) performed, on separate days, HIIE conditions consisting of 8 x 1-minute work-intervals at 70%, 85%, or 100% peak power separated by 75 seconds recovery at 20 W. Affect, enjoyment and rating of perceived exertion (RPE) were recorded before, during, and after HIIE. Heart rate (HR) and oxygen uptake were collected during HIIE. Affect declined in all conditions (p < 0.01) but 100%HIIE elicited significantly lower affect than 70%HIIE and 85%HIIE at work-interval 8 (all p < 0.02, ES > 1.74; 70%HIIE = 2.5 ± 0.8; 85%HIIE = 1.1 ± 1.5; 100%HIIE = -1.5 ± 1.4 on feeling scale). Similar enjoyment was evident during and after all conditions (all p > 0.44). RPE was significantly higher during 100%HIIE than 70%HIIE and 85%HIIE across all work-intervals (all p < 0.01, ES > 1.56). The majority of the participants attained ≥90%HRmax during 85%HIIE (87%) and 100%HIIE (100%), but not during 70%HIIE (6%). Affect responses during HIIE are dependent on the intensity of the work-interval and are not entirely negative (unpleasant feelings). Despite similar enjoyment, positive affect experienced during 70%HIIE and 85%HIIE could serve as a strategy to encourage exercise adoption and adherence in adolescents, but only 85%HIIE elicits sufficient HR stimulus to facilitate potential health benefits.

Flowers and spiders in spatial stimulus-response compatibility: does affective valence influence selection of task-sets or selection of responses?

The present study examined the effect of stimulus valence on two levels of selection in the cognitive system, selection of a task-set and selection of a response. In the first experiment, participants performed a spatial compatibility task (pressing left and right keys according to the locations of stimuli) in which stimulus-response mappings were determined by stimulus valence. There was a standard spatial stimulus-response compatibility (SRC) effect for positive stimuli (flowers) and a reversed SRC effect for negative stimuli (spiders), but the same data could be interpreted as showing faster responses when positive and negative stimuli were assigned to compatible and incompatible mappings, respectively, than when the assignment was opposite. Experiment 2 disentangled these interpretations, showing that valence did not influence a spatial SRC effect (Simon effect) when task-set retrieval was unnecessary. Experiments 3 and 4 replaced keypress responses with joystick deflections that afforded approach/avoidance action coding. Stimulus valence modulated the Simon effect (but did not reverse it) when the valence was task-relevant (Experiment 3) as well as when it was task-irrelevant (Experiment 4). Therefore, stimulus valence influences task-set selection and response selection, but the influence on the latter is limited to conditions where responses afford approach/avoidance action coding.

A test-retest assessment of the effects of mental load on ratings of affect, arousal and perceived exertion during submaximal cycling.

This study aimed to test the effects of mental (i.e. executive) load during a dual physical-mental task on ratings of perceived exertion (RPE), affective valence, and arousal. The protocol included two dual tasks with matched physical demands but different executive demands (2-back and oddball), carried out on different days. The procedure was run twice to assess the sensitivity and stability of RPE, valence and arousal across the two trials. Linear mixed-effects analyses showed less positive valence (-0.44 points on average in a 1-9 scale; Rß2 = 0.074 [CI90%, 0.052-0.098]), and heightened arousal (+0.13 points on average in a 1-9 scale; Rß2 = 0.006 [CI90%, 0.001-0.015]), for the high executive load condition, but showed no effect of mental load on RPE. Separated analyses for the two task trials yielded best-fitting models that were identical across trials for RPE and valence, but not for arousal. Model fitting was improved by assuming a 1-level autoregressive covariance structure for all analyses. In conclusion, executive load during a dual physical-mental task modulates the emotional response to effort, but not RPE. The autoregressive covariance suggests that people tend to anchor estimates on prior ones, which imposes certain limits on scales' usability.

The effect of sleep deprivation on retrieval of emotional memory: a behavioural study using film stimuli.

Although the deleterious effects of sleep deprivation on memory consolidation are well documented, it is still unclear how the facilitating effect of emotions on memory consolidation processes could be modulated by the lack of sleep. In this study, we investigated the effects of sleep deprivation on episodic memory using emotional and non-emotional film stimuli. Forty-eight healthy subjects, divided into a sleep group (SG) and a sleep-deprived (SD) group, completed an Encoding and a Recall phase. Participants in the SD group were sleep deprived the night immediately following the Encoding phase, whereas the control group slept at home. The Recall phase was administered to all subjects 48 h after the Encoding. During the Encoding phase, six film clips of different valence (two positive, two neutral and two negative) were presented to the participants. During the Recall phase, episodic memory was assessed by a recognition task. Results showed that the SD group had a lower discrimination memory performance for all stimuli compared to the SG, confirming the deleterious effect of sleep deprivation on episodic memory consolidation. Therefore, lack of sleep severely impairs the consolidation of both emotional and neutral memories, as valence-related effects on memory consolidation were not observed after sleep deprivation.

The effect of sleep deprivation on the encoding of contextual and non-contextual aspects of emotional memory.

Sleep loss affects emotional memory, but the specific effects on its contextual and non-contextual aspects are unknown. In this study we investigated the possible differential influence of one night of sleep deprivation on the encoding and subsequent recall of these two aspects of emotional information. Forty-eight healthy subjects, divided in a sleep deprivation (SD) and a well-rested group (WR), completed two testing sessions: the encoding session took place after one night of sleep for the WR and after one night of sleep deprivation for the SD group; the recall session after two nights of recovery sleep for both groups. During the encoding session, 6 clips of films of different valence (2 positive, 2 neutral and 2 negative) were presented to the participants. During the recall session, the non-contextual emotional memory was assessed by a recognition task, while the contextual emotional memory was evaluated by a temporal order task. The SD group showed a worst non-contextual recognition of positive and neutral events compared to WR subjects, while recognition of negative items was similar in the two groups. Instead, the encoding of the temporal order resulted deteriorated in the SD participants, independent of the emotional valence of the items. These results indicate that sleep deprivation severely impairs the encoding of both contextual and non-contextual aspects of memory, resulting in significantly worse retention two days later. However, the preserved recognition of negative non-contextual events in sleep deprived subjects suggests that the encoding of negative stimuli is more "resistant" to the disruptive effects of sleep deprivation.

Self-Paced Exercise, Affective Response, and Exercise Adherence: A Preliminary Investigation Using Ecological Momentary Assessment.

Affective response to exercise may mediate the effects of self-paced exercise on exercise adherence. Fiftynine low-active (exercise <60 min/week), overweight (body mass index: 25.0-39.9) adults (ages 18-65) were randomly assigned to self-paced (but not to exceed 76% maximum heart rate) or prescribed moderate intensity exercise (64-76% maximum heart rate) in the context of otherwise identical 6-month print-based exercise promotion programs. Frequency and duration of exercise sessions and affective responses (good/bad) to exercise were assessed via ecological momentary assessment throughout the 6-month program. A regression-based mediation model was used to estimate (a) effects of experimental condition on affective response to exercise (path a = 0.20, SE = 0.28, f2 = 0.02); (b) effects of affective response on duration/latency of the next exercise session (path b = 0.47, SE = 0.25, f2 = 0.04); and (c) indirect effects of experimental condition on exercise outcomes via affective response (path ab = 0.11, SE = 0.06, f2 = 0.10). Results provide modest preliminary support for a mediational pathway linking self-paced exercise, affective response, and exercise adherence.

Emotional working memory during sustained wakefulness.

In the present study we investigated whether one night of sleep deprivation can affect working memory (WM) performance with emotional stimuli. Twenty-five subjects were tested after one night of sleep deprivation and after one night of undisturbed sleep at home. As a second aim of the study, to evaluate the cumulative effects of sleep loss and of time-of-day changes on emotional WM ability, the subjects were tested every 4 h, from 22:00 to 10:00 hours, in four testing sessions during the sleep deprivation period (deprivation sessions: D1, D2, D3 and D4). Subjects performed the following test battery: Psychomotor Vigilance Task, 0-back task, 2-back task and an 'emotional 2-back task' with neutral, positive and negative emotional pictures selected from the International Affective Picture System. Results showed lower accuracy in the emotional WM task when the participants were sleep-deprived relative to when they had slept, suggesting the crucial role of sleep for preserving WM ability. In addition, the accuracy for the negative pictures remains stable during the sessions performed from 22:00 to 06:00 hours (D1, D2 and D3), while it drops at the D4 session, when the participants had accumulated the longest sleep debt. It is suggested that, during sleep loss, attentional and WM mechanisms may be sustained by the higher arousing characteristics of the emotional (negative) stimuli.

Examining the effects of increasing then decreasing exercise intensity within a session of aerobic exercise.

Recent studies have examined the relations between the slope of pleasure experienced during exercise and remembered pleasure, forecasted pleasure, and enjoyment. OBJECTIVES: This study advances this line of research by examining the effects of exposing participants to exercise that increases in intensity and then decreases in intensity. METHODS: In a within-subjects design, participants completed three exercise sessions matched for total and average work. One session steadily increased in intensity, another steadily decreased in intensity, and a third increased-then-decreased in intensity. Remembered pleasure, forecasted pleasure, and exercise enjoyment served as primary outcome variables. RESULTS: Remembered pleasure, forecasted pleasure, and enjoyment did not differ between conditions. Remembered pleasure was positively associated with mean experienced pleasure, the overall slope of pleasure during the exercise session, affect experienced at the end of exercise, forecasted pleasure, accomplishment, and enjoyment. CONCLUSIONS: These data add to a growing literature on the effects of patterns of exercise intensity on affective responses to exercise. The results are discussed in context of previous and more recent research.

The spread of affective and semantic valence representations across states.

In many decision problems, outcomes are not reached after a single action but rather after a series of events or states. To optimize decisions over multiple states, representations of how good or bad the outcomes are, that is, the outcomes' valence, should spread across states. One mechanism for valence spreading is a temporal, state-independent process in which a single valence representation is updated when an outcome is experienced and fades away afterwards. Each state's valence is based on its temporal proximity to the experienced outcome. An alternative, state-dependent mechanism relies on the structure of transitions between states, updating a separate valence representation for each state according to its spatial distance from the outcomes. We examined how these mechanistic accounts shape the spread of two formats of valence representation, feelings (affective valence) and knowledge (semantic valence), between states. In two pre-registered experiments (N = 585), we used a novel task in which participants move in a four-state maze, one of which contains an outcome. The participants provide self-reports of affective and semantic valence throughout the maze and after finishing it. Results show that the affective representation of negative valence is more localized in state-space than the semantic representation. We also found evidence for the relative reliance of the affective valence on a temporal, state-independent mechanism and of the semantic valence on a structured, state-dependent mechanism. Our findings provide mechanistic accounts for the differences between affective and semantic valence representations and indicate how such representations may play a role in associative learning and decision-making.

Enjoyment and Affective Responses to Moderate and High-Intensity Exercise: A Randomized Controlled Trial in Individuals with Subsyndromal PTSD.

This crossover randomized controlled trial examined the acute psychological effects of a bout of moderate-intensity continuous aerobic exercise (MICE) and a bout of high-intensity functional exercise (HIFE), relative to a no-exercise sedentary control (SED), in participants (N = 21; 15 f; 24.7 ± 9.3 years) with subsyndromal post-traumatic stress disorder (PTSD). Affective state (Energy, Tiredness, Tension, Calmness) was assessed before (Pre), immediately after (Post 0), 20-min after (Post 20), and 40-min after (Post 40) each condition. Affective valence was assessed during each condition, and exercise enjoyment was assessed at Post 0. Enjoyment was significantly greater following HIFE and MICE relative to SED. Energy was significantly increased Post 0 HIFE and MICE but decreased Post 0 SED. Tension was reduced following all conditions and was significantly lower at Post 40 relative to Pre for HIFE, MICE, and SED. Tiredness was significantly reduced at Post 40 relative to Pre following MICE only, while Calmness was significantly lower at Post 40 relative to Pre following MICE and SED. Overall, both exercise conditions were enjoyed to a greater extent than the control, but MICE may provide greater psychological benefits with respect to Calmness and Tiredness. This study is among the first to assess acute changes in affective states relative to various exercise modes in individuals living with subsyndromal PTSD.

Beyond Rubik: The Embodiment-Presence-Interactivity Cube applied to exercise.

Evidence-based interventions are needed to promote engagement in physical activity. Audio-visual stimuli are frequently employed to enhance the exercise experience. Nonetheless, there is a paucity of research that examines the qualities of technological devices that are employed. Using the Embodiment-Presence-Interactivity Cube (Flavián et al., 2019) as a guiding conceptual framework, the aim of this registered report was to examine how each dimension of the cube (i.e., embodiment, presence and interactivity) influenced a range of exercise-related affective and perceptual variables. A counterbalanced within-subjects design was employed (N = 24). Participants completed 20-min exercise bouts on a cycle ergometer under four conditions: Television, augmented reality, 360° video and virtual reality. A repeated-measures ANOVA indicated a significant Condition × Timepoint interaction for affective valence (p = 0.046), with greater embodiment offered by technological devices leading to more positive responses. Analyses also indicated main effects of condition for exercise enjoyment, remembered pleasure and forecasted pleasure, with greater presence of technological devices leading to more positive responses. Technologies that combine high levels of embodiment, presence and interactivity (e.g., virtual reality) appear to yield several benefits in terms of in-task (e.g., affective valence) and post-task (e.g., remembered pleasure) responses for exercise conducted at ventilatory threshold.

One-HIIT Wonder: Can Music Make High-Intensity Interval Training More Pleasant?

The use of music as an aid to recovery during and after exercise is an area of growing scientific interest. We investigated the effects of in-task, asynchronous music and respite-active music (i.e., music used for active recovery in between high-intensity exercise bouts) on a range of psychological, psychophysical and psychophysiological outcomes. Participants (N = 28; 14 females) made five laboratory visits for: (a) pre-test/familiarisation; (b) fast-tempo music during supramaximal exercise bouts and medium-tempo during active-recovery periods; (c) fast-tempo during exercise and no music during recovery; (d) no music during exercise and medium-tempo during recovery; and (e) a no-music (throughout) control. A cycle ergometer-based HIIT protocol comprising 6 × 60-s bouts at 100% Wmax with 75-s active recovery was administered. Measures were taken at the end of supramaximal bouts and active recovery periods (RPE, state attention, core affect, state motivation), then upon cessation of the protocol (remembered pleasure and exercise enjoyment). Heart rate and heart rate variability (HRV) measures were taken throughout. The music manipulations only had an effect on state motivation, which was higher (p = .036) in the fast tempo-medium tempo condition compared to no-music control (Cohen's d = 0.49), and the SDNN component of HRV, which was lower (p = .007) in the fast tempo-no music condition compared to control (Cohen's d = 0.32). Collectively, the present findings do not support any of the study hypotheses regarding the music-related manipulations, and do not concur with the findings of related studies (e.g., Karageorghis et al., 2021). The unexpected results are discussed with reference to extant theory, and recommendations are offered in regard to music-related applications.