When Studying Affective Responses to Exercise, the Definition of "Intensity" Must Reference Homeostatic Perturbations: A Retort to Vollaard et al

In articles on the methodology of studies investigating affective and enjoyment responses to high-intensity interval training, we noted that, occasionally, exercise conditions described as involving "high" intensity exhibited heart rates that were only as high as, or even lower than, heart rates recorded during comparator conditions described as being of "moderate" intensity. Drs. Vollaard, Metcalfe, Kinghorn, Jung, and Little suggest instead that exercise intensity in high-intensity interval-training studies can be defined in terms of percentages of peak workload. Although we maintain that defining exercise intensity in terms of percentages of maximal heart rate is a suboptimal way to quantify the degree of homeostatic perturbations in response to exercise, we are unconvinced that definitions of intensity relying solely on workload are appropriate for studies investigating affective and enjoyment responses to exercise. The reason is that affect is theorized to have evolved to relay information about homeostatic perturbations to consciousness.

Affective responses to stretching exercises: Exploring the timing of assessments

Affective responses during exercise have been identified as a predictor of exercise adherence. However, research has been mostly limited to aerobic and resistance exercise. Considering that stretching activities are also an important component of physical fitness, this quasi-experimental study was designed to: 1) compare affective responses during and immediately after stretching exercises in apparently healthy adults, and 2) assess the consistency and repeatability of affect ratings obtained one week apart. For this purpose, we analyzed the Feeling Scale (FS) and Felt Arousal Scale (FAS) ratings using Time (during and after stretching) x Intensity (light, moderate, vigorous) x Stretched Muscle Group (quadriceps, hamstrings, glutes, latissimus dorsi, triceps) with repeated measures analysis of variance (ANCOVA) in 34 participants (21 males; aged 32.8 ± 8.6 years). The repeatability of FS and FAS ratings was assessed using two-way random-effects models, Intraclass Correlation Coefficients (ICC), and Bland-Altman plots. FS scores were higher following the stretching exercises, whereas FAS scores were lower, particularly in the vigorous intensity. In general, the inter-day repeatability for FS and FAS measurements was good across muscle groups. ICC tended to be higher at vigorous intensities. Ratings of core affect can be collected during static passive stretches using the FAS and FAS in ecologically valid settings. These results suggest that an adequate assessment of core affective responses to stretching activities should be performed during the exercises.

Extraordinary Claims in the Literature on High-Intensity Interval Training (HIIT): I. Bonafide Scientific Revolution or a Looming Crisis of Replication and Credibility?

The literature on high-intensity interval training (HIIT) contains claims that, if true, could revolutionize the science and practice of exercise. This critical analysis examines two varieties of claims: (i) HIIT is effective in improving various indices of fitness and health, and (ii) HIIT is as effective as more time-consuming moderate-intensity continuous exercise. Using data from two recent systematic reviews as working examples, we show that studies in both categories exhibit considerable weaknesses when judged through the prism of fundamental statistical principles. Predominantly, small-to-medium effects are investigated in severely underpowered studies, thus greatly increasing the risk of both type I and type II errors of statistical inference. Studies in the first category combine the volatility of estimates associated with small samples with numerous dependent variables analyzed without consideration of the inflation of the type I error rate. Studies in the second category inappropriately use the p > 0.05 criterion from small studies to support claims of 'similar' or 'comparable' effects. It is concluded that the situation in the HIIT literature is reminiscent of the research climate that led to the replication crisis in psychology. As in psychology, this could be an opportunity to reform statistical practices in exercise science.

Exploring the impact of individualized pleasure-oriented exercise sessions in a health club setting: Protocol for a randomized controlled trial

Research on the relationship between exercise-induced affect and exercise or physical activity behavior has gained momentum in recent years, yielding several observational and longitudinal studies. However, experimental tests demonstrating a causal role of affective responses on exercise adherence are lacking. Given the need to devise exercise prescriptions that can facilitate adherence and promote regular physical activity, a Randomized Controlled Trial targeting individual pleasurable responses in a health-club setting will be conducted. The experimental protocol will compare two individualized evaluation, prescription, and supervision methods, adjusted for intensity, with the aim to explore their impact on behavioral, affective, and motivational outcomes. The planned study will be a pragmatic randomized, single-blinded, controlled superiority trial with two parallel groups and an allocation ratio of 1:1. Apparently healthy volunteer participants (N = 46) between 18 and 45 years old, who are not regularly active, will be randomly allocated to a control or experimental group. The control group will follow a general American College of Sports Medicine exercise prescription; the experimental group will follow the same prescription but with enhancements aimed at promoting pleasure: (1) individualization based on individual differences in preference for and tolerance of exercise intensity; (2) self-regulation of intensity; and (3) repeated assessments of core affect. The primary outcome will be post-intervention exercise-session attendance. Affective and motivational variables will be examined as secondary outcomes. The results are expected to advance exercise prescriptions by promoting affective regulation, thus helping to improve exercise adherence and related outcomes. TRIAL REGISTRATION: ClinicalTrials.gov; ID: NCT05416593.

Affective Responses to Increasing- and Decreasing-Intensity Resistance Training Protocols

This study compared the effects of an increasing-intensity (UP) and a decreasing-intensity (DOWN) resistance training protocol on affective responses across six training sessions. Novice participants (Mage 43.5 ± 13.7 years) were randomly assigned to UP (n = 18) or DOWN (n = 17) resistance training groups. Linear mixed-effects models showed that the evolution of affective valence within each training session was significantly moderated by the group (b = -0.45, p ≤ .001), with participants in the UP group reporting a decline in pleasure during each session (b = -0.82) and the DOWN group reporting an improvement (b = 0.97; ps < .001). Remembered pleasure was significantly higher in the DOWN group compared to the UP group (b = 0.57, p = .004). These findings indicate that a pattern of decreasing intensity throughout a resistance exercise session can elicit more positive affective responses and retrospective affective evaluations of resistance training.

Extraordinary claims in the literature on high-intensity interval training (HIIT): III. Critical analysis of four foundational arguments from an interdisciplinary lens

Kinesiology aspires to be an integrated, interdisciplinary field that studies human movement from multiple perspectives. However, the main societal deliverables of the field, namely exercise prescriptions and physical activity recommendations, still reflect fragmentation, placing more emphasis on physiological outcomes than on behavioral and other considerations. Recently, researchers have called for the introduction of High-Intensity Interval Training (HIIT) to the domain of public health, based on the argument that HIIT can maximize fitness and health benefits for a fraction of the time recommended by the prevailing model of physical activity in public-health guidelines. Here, we show that an unintended side-effect of arguments underpinning the implementation of HIIT in the domain of public health might have been the exacerbation of segmentation. To highlight the value of interdisciplinarity, four foundational claims in support of HIIT are critiqued by tapping into cognate literatures: (1) the primary reason people do not exercise is lack of time, (2) HIIT is relevant to public health, (3) HIIT is being proposed as merely another option, so there is no basis for controversy, and (4) HIIT is safe and well tolerated. These claims are contradicted by credible lines of evidence. To improve the accuracy and effectiveness of its public claims, kinesiology should remain committed to the ideals of integration and interdisciplinarity.

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.

A Methodological Checklist for Studies of Pleasure and Enjoyment Responses to High-Intensity Interval Training: Part II. Intensity, Timing of Assessments, Data Modeling, and Interpretation

Recent studies have concluded that high-intensity interval training should be seen as a "viable alternative" to, and may be more enjoyable than, moderate-intensity continuous exercise. If true, these claims have the potential to revolutionize the science and practice of exercise, establishing high-intensity interval training as not only a physiologically effective exercise modality but also a potentially sustainable one. However, these claims stand in contrast to voluminous evidence according to which high levels of exercise intensity are typically experienced as less pleasant than moderate levels. To help researchers, peer reviewers, editors, and critical readers appreciate possible reasons for the apparently conflicting results, we present a checklist that identifies crucial methodological elements in studies investigating the effects of high-intensity interval training on affect and enjoyment. This second installment covers how "high-intensity" and "moderate-intensity" experimental conditions are defined, the timing of assessments of affect, the modeling of affective responses, and data interpretation.

Baseless Claims and Pseudoscience in Health and Wellness: A Call to Action for the Sports, Exercise, and Nutrition-Science Community

The global health and wellness industry has an estimated value of US$4 trillion. Profits derive from heath club memberships, exercise classes, diets, supplements, alternative 'therapies', and thousands of other products and services that are purported to improve health, recovery, and/or sports performance. The industry has expanded at an alarming rate, far outstripping the capacity of federal bodies to regulate the market and protect consumer interests. As a result, many products are sold on baseless or exaggerated claims, feigned scientific legitimacy, and questionable evidence of safety and efficacy. This article is a consciousness raiser. Herein, the implications of the mismatch between extraordinary health and performance claims and the unextraordinary scientific evidence are discussed. Specifically, we explore how pseudoscience and so-called 'quick fix' interventions undermine initiatives aimed at evoking long-term behavior change, impede the ongoing pursuit of sports performance, and lead to serious downstream consequences for clinical practice. Moreover, pseudoscience in health and wellness, if left unchecked and unchallenged, may have profound implications for the reputation of exercise science as a discipline. This is a call to action to unify exercise scientists around the world to more proactively challenge baseless claims and pseudoscience in the commercial health and wellness industry. Furthermore, we must shoulder the burden of ensuring that the next generation of exercise scientists are sufficiently skilled to distinguish science from pseudoscience, and information from mis- and disinformation. Better population health, sports performance, and the very reputation of the discipline may depend on it.

Extraordinary claims in the literature on high-intensity interval training (HIIT): IV. Is HIIT associated with higher long-term exercise adherence?

Nonadherence to and dropout from regular exercise and physical activity are important reasons why the field of exercise science has yet to fulfill its promise of improving public health on a global scale. Researchers have claimed that High-Intensity Interval Training (HIIT) is a feasible and sustainable exercise modality that may result in higher long-term adherence than moderate-intensity continuous exercise. If true, this would be a breakthrough discovery that could unlock the potential of exercise as a health-promoting intervention. We performed a systematic search of the literature and identified eight trials comparing HIIT to moderate-intensity continuous exercise, all of which involved follow-up periods of at least 12 months (i.e., SWIFT, Small Steps for Big Changes, SAINTEX-CAD, SMARTEX-HF, Generation 100, FITR, OptimEx-Clin, HITTS). Findings from these trials demonstrate that, while unsupervised, individuals initially assigned to HIIT tend to exercise at lower-than-prescribed intensities and HIIT groups demonstrate no advantage in long-term adherence.

Updating goal-setting theory in physical activity promotion: a critical conceptual review

Goal-setting is a widely used and accepted strategy for promoting physical activity. Locke and Latham's goal-setting theory is the primary theoretical framework for setting goals in psychology and plays a prominent role in physical activity promotion. Recently, however, there have been calls to reconsider current goal-setting practice in this field. Therefore, we aimed to critically review and update the application of goal-setting theory in physical activity promotion, by examining core developments in this theory since 1990. Current practice relies on setting specific 'performance' goals as a means of increasing physical activity (e.g., 10,000 steps; national physical activity guidelines). This approach was initially consistent with key tenets of goal-setting theory. However, since 1990 this theory has evolved to differentiate between performance and learning goals. Both goal types are context-dependent and it is now recognised that, in some cases, performance goals can even be detrimental to the achievement of desired outcomes. Consequently, current practice may be theoretically appropriate for physically active individuals but a different approach (e.g., learning goals) may be preferable for inactive individuals who are new to physical activity (i.e., most of the population). We conclude by discussing implications for policy, research, and practice in goal-setting for physical activity promotion.

Critical Review of Measurement Practices in the Study of Automatic Associations of Sedentary Behavior, Physical Activity, and Exercise

Studies of automatic associations of sedentary behavior, physical activity, and exercise are proliferating, but the lack of information on the psychometric properties of relevant measures is a potential impediment to progress. The purpose of this review was to critically summarize measurement practices in studies examining automatic associations related to sedentary behavior, physical activity, and exercise. Of 37 studies, 27 (73%) did not include a justification for the measure chosen to assess automatic associations. Additional problems have been noted, including the nonreporting of psychometric information (validity, internal consistency, test-retest reliability) and the lack of standardization of procedures (e.g., number, type of stimuli). The authors emphasize the need to select measures based on conceptual arguments and psychometric evidence and to standardize measurement procedures. To facilitate progress, the review concludes with a proposal for conceptually appropriate validation criteria to be used in future studies.

Affect and prefrontal hemodynamics during exercise under immersive audiovisual stimulation: Improving the experience of exercise for overweight adults

OBJECTIVE

Research on methods of improving the affective experience of exercise remains limited, especially for low-active overweight adults. We investigated the effectiveness of a virtual-reality headset and headphones in improving affective responses over conventionally delivered audiovisual stimulation.

METHODS

Low-active, overweight adults (16 women, 5 men; age: 34.67 ± 9.62 years; body mass index: 28.56 ± 4.95 kg/m²; peak oxygen uptake for men: 29.14 ± 6.56 mL/kg/min, for women: 22.67 ± 4.52 mL/kg/min, mean ± SD) completed 15-min sessions of recumbent cycling at the ventilatory threshold: (a) high immersion (HI, virtual reality headset and headphones), (b) low immersion (LI, television screen and speakers), and (c) Control. During-exercise pleasure and post-exercise enjoyment were self-reported. Oxygenation of the right dorsolateral prefrontal cortex (dlPFC) was assessed with near infrared spectroscopy.

RESULTS

Higher pleasure was reported during HI than during LI and Control (Condition × Time interaction; p < 0.001, η _p ² = 0.43). Participants who reported a preference for low exercise intensity showed higher dlPFC oxygenation during Control, but this difference diminished during LI and HI (Condition × Time × Preference interaction; p = 0.036, η_p ² = 0.10).

CONCLUSION

Compared with conventionally delivered audiovisual stimulation, using a virtual-reality headset strengthens the dissociative effect, further improving affective responses to exercise at the ventilatory threshold among overweight, low-active adults. Presumably by competing with interoceptive afferents at the level of sensory input, audiovisual stimulation may lessen reliance on cognitive efforts to attenuate declining affect, as indicated by lower right dlPFC activity, particularly among participants disinclined toward high exercise intensity.

Dynamics of pleasure-displeasure at the limit of exercise tolerance: conceptualizing the sense of exertional physical fatigue as an affective response

The search for variables involved in the regulation and termination of exercise performance has led to integrative models that attribute a central role to the brain and utilize an array of psychological terms (e.g. sensation, perception, discomfort, tolerance). We propose that theorizing about exercise regulation would benefit from establishing cross-disciplinary bridges to research fields, such as affective psychology and neuroscience, in which changes along the dimension of pleasure-displeasure are considered the main channel via which homeostatic perturbations enter consciousness and dictate corrective action (slowing down or stopping). We hypothesized that ratings of pleasure-displeasure would respond to the severity of homeostatic perturbation and would be related to time to exhaustion during exercise performed at an unsustainable intensity. In a within-subjects experiment (N=15, 13 men and 2 women, age 23.4±2.2 years; maximal oxygen uptake 46.0±8.0 ml kg^-1 min^-1), we compared the slope of ratings of pleasure-displeasure (acquired every 1 min) during cycling exercise at a power output 10% above critical power until volitional termination under glycogen-loaded and glycogen-depleted conditions. As hypothesized, ratings of pleasure-displeasure declined more steeply under glycogen depletion (P=0.009, d=0.70) and correlated closely with time to exhaustion under both glycogen-loaded (r=0.85; P<0.001) and glycogen-depleted conditions (r=0.83; P<0.001). We conclude that in exercise, as in other domains, changes in pleasure-displeasure may be the main channel via which homeostatic perturbations enter consciousness. This proposal may have important implications for conceptualizing and identifying the neurobiological mechanisms of the sense of exertional physical fatigue.

Mass media representations of the evidence as a possible deterrent to recommending exercise for the treatment of depression: Lessons five years after the extraordinary case of TREAD-UK

Exercise or physical activity are recommended options within stepped-care treatment models for depression. However, few physicians present these options to patients, in part because of the impression that the supporting evidence is weak or inconsistent. We speculate that the coocurrence of "counter-messaging" and deficient critical appraisal may lead to such impressions. We focus on TREAD-UK (ISRCTN16900744), the largest trial to investigate "whether physical activity can be an effective treatment for depression within primary care". In media statements, researchers declared that exercise was ineffective in lowering depression. We examined (a) the results of the trial, critiques, and rejoinders, (b) the impact on internet searches, and (c) whether TREAD-UK was critically appraised, as reflected in citing articles. We show that the results of TREAD-UK were misrepresented. The media campaign resulted in a fourfold increase in relevant internet searches. Of articles characterising the results, 57% adopted the interpretation that exercise failed to lower depression, whereas only 17% were critiques. We identify similarities to media portrayals of the OPERA (ISRCTN43769277), DEMO (NCT00103415), and DEMO-II trials (NCT00695552). We note a disconcerting trend of media campaigns that misrepresent the effects of exercise on depression and call for increased scrutiny in peer reviewing both pre- and post-publication.

Physical Exercise in Major Depression: Reducing the Mortality Gap While Improving Clinical Outcomes

Major depression shortens life while the effectiveness of frontline treatments remains modest. Exercise has been shown to be effective both in reducing mortality and in treating symptoms of major depression, but it is still underutilized in clinical practice, possibly due to prevalent misperceptions. For instance, a common misperception is that exercise is beneficial for depression mostly because of its positive effects on the body ("from the neck down"), whereas its effectiveness in treating core features of depression ("from the neck up") is underappreciated. Other long-held misperceptions are that patients suffering from depression will not engage in exercise even if physicians prescribe it, and that only vigorous exercise is effective. Lastly, a false assumption is that exercise may be more harmful than beneficial in old age, and therefore should only be recommended to younger patients. This narrative review summarizes relevant literature to address the aforementioned misperceptions and to provide practical recommendations for prescribing exercise to individuals with major depression.

Exercise as antidepressant treatment: Time for the transition from trials to clinic?

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The mysterious case of the public health guideline that is (almost) entirely ignored: call for a research agenda on the causes of the extreme avoidance of physical activity in obesity

Physical activity and exercise guidelines for weight management call for at least 60 min of daily activity. However, these documents fail to acknowledge that almost no obese adults meet this target and that non-adherence and dropout are even higher among obese individuals than the general population. The reasons for this level of activity avoidance among obese individuals remain poorly understood, and there are no evidence-based methods for addressing the problem. Opinions among exercise scientists are polarized. Some advocate moderate intensity and long duration, whereas others call for high intensity and shorter duration. The latter approach attributes the inactivity and high dropout to limited discretionary time and the slow accrual of visible benefits. However, higher intensity has been associated with non-adherence and dropout, whereas longer duration has not. A conceptual model is then proposed, according to which obesity interacts with intensity, causing physical activity and exercise to be associated with reduced pleasure among obese individuals. We theorize that, in turn, repeated experiences of reduced pleasure lead to avoidance. On this basis, we call for a research agenda aimed at identifying the causes of activity-associated and exercise-associated displeasure in obesity and, by extension, the causes of the extreme physical inactivity among obese individuals.

Can You Have Your Vigorous Exercise and Enjoy It Too? Ramping Intensity Down Increases Postexercise, Remembered, and Forecasted Pleasure

There is a paucity of methods for improving the affective experience of exercise. We tested a novel method based on discoveries about the relation between exercise intensity and pleasure, and lessons from behavioral economics. We examined the effect of reversing the slope of pleasure during exercise from negative to positive on pleasure and enjoyment, remembered pleasure, and forecasted pleasure. Forty-six adults were randomly assigned to a 15-min bout of recumbent cycling of either increasing intensity (0-120% of watts corresponding to the ventilatory threshold) or decreasing intensity (120-0%). Ramping intensity down, thereby eliciting a positive slope of pleasure during exercise, improved postexercise pleasure and enjoyment, remembered pleasure, and forecasted pleasure. The slope of pleasure accounted for 35-46% of the variance in remembered and forecasted pleasure from 15 min to 7 days postexercise. Ramping intensity down makes it possible to combine exposure to vigorous and moderate intensities with a pleasant affective experience.

Role of self-reported individual differences in preference for and tolerance of exercise intensity in fitness testing performance

Performance in fitness tests could depend on factors beyond the bioenergetic and skeletomuscular systems, such as individual differences in preference for and tolerance of different levels of exercise-induced somatosensory stimulation. Although such individual-difference variables could play a role in exercise testing and prescription, they have been understudied. The purpose of these studies was to examine the relationships of self-reported preference for and tolerance of exercise intensity with performance in fitness tests. Participants in study I were 516 men and women volunteers from a campus community, and participants in study II were 42 men recruit firefighters undergoing a 6-week training program. Both the Preference and Tolerance scores exhibited significant relationships with performance in several fitness tests and with body composition and physical activity participation. Preference and Tolerance did not change after the training program in study II, despite improvements in objective and perceived fitness, supporting their conceptualization as dispositional traits. Preference and Tolerance scores could be useful not only in ameliorating the current understanding of the determinants of physical performance, but also in personalizing exercise prescriptions and, thus, delivering exercise experiences that are more pleasant, tolerable, and sustainable.

Knowledge of Exercise Prescription Guidelines Across One 4-Year Kinesiology Curriculum

PURPOSE

Knowledge of evidence-based exercise prescription guidelines is considered a cornerstone of responsible professional practice. While many academics insist that a university degree in kinesiology or a related field should be required for all exercise professionals, the learning of exercise prescription guidelines that takes place during the course of a university degree program has not been investigated.

METHOD

An 11-question knowledge quiz about the frequency, duration, and intensity of cardiovascular exercise recommended by the American College of Sports Medicine (Garber et al., 2011) was administered to 683 undergraduate students majoring in kinesiology and 89 certified exercise professionals.

RESULTS

Knowledge scores improved significantly, F(4, 764) = 16.69, p < .001, η2 = .08, from the freshmen, who scored 24.30%, to the seniors, who scored 36.25%. Seniors did not differ significantly from the professionals, who scored 40.65%, despite the fact that 58.14% of professionals had graduate degrees and 44.95% had multiple certifications. However, 82.77% of seniors perceived that their knowledge of the guidelines (rated 5.48 out of 10) was lower than that required "to be able to function as an exercise professional safely and effectively" (rated 8.17).

CONCLUSION

These data suggest that although significant learning of the guidelines occurs in a typical kinesiology curriculum, there is considerable room for improvement.

Can high-intensity exercise be more pleasant?: attentional dissociation using music and video

Theories suggest that external stimuli (e.g., auditory and visual) may be rendered ineffective in modulating attention when exercise intensity is high. We examined the effects of music and parkland video footage on psychological measures during and after stationary cycling at two intensities: 10% of maximal capacity below ventilatory threshold and 5% above. Participants (N = 34) were exposed to four conditions at each intensity: music only, video only, music and video, and control. Analyses revealed main effects of condition and exercise intensity for affective valence and perceived activation (p < .001), state attention (p < .05), and exercise enjoyment (p < .001). The music-only and music-and-video conditions led to the highest valence and enjoyment scores during and after exercise regardless of intensity. Findings indicate that attentional manipulations can exert a salient influence on affect and enjoyment even at intensities slightly above ventilatory threshold.

The pleasure and displeasure people feel when they exercise at different intensities: decennial update and progress towards a tripartite rationale for exercise intensity prescription

The public health problem of physical inactivity has proven resistant to research efforts aimed at elucidating its causes and interventions designed to alter its course. Thus, in most industrialized countries, the majority of the population is physically inactive or inadequately active. Most theoretical models of exercise behaviour assume that the decision to engage in exercise is based on cognitive factors (e.g. weighing pros and cons, appraising personal capabilities, evaluating sources of support). Another, still-under-appreciated, possibility is that these decisions are influenced by affective variables, such as whether previous exercise experiences were associated with pleasure or displeasure. This review examines 33 articles published from 1999 to 2009 on the relationship between exercise intensity and affective responses. Unlike 31 studies that were published until 1998 and were examined in a 1999 review, these more recent studies have provided evidence of a relation between the intensity of exercise and affective responses. Pleasure is reduced mainly above the ventilatory or lactate threshold or the onset of blood lactate accumulation. There are pleasant changes at sub-threshold intensities for most individuals, large inter-individual variability close to the ventilatory or lactate threshold and homogeneously negative changes at supra-threshold intensities. When the intensity is self-selected, rather than imposed, it appears to foster greater tolerance to higher intensity levels. The evidence of a dose-response relation between exercise intensity and affect sets the stage for a reconsideration of the rationale behind current guidelines for exercise intensity prescription. Besides effectiveness and safety, it is becoming increasingly clear that the guidelines should take into account whether a certain level of exercise intensity would be likely to cause increases or decreases in pleasure.

The affective beneficence of vigorous exercise revisited

OBJECTIVES: High exercise intensity may be associated with reduced adherence to exercise programmes, possibly because it is perceived as aversive. However, several authors have suggested that an intensity as high as 60% or 70% of maximal aerobic capacity (VO(2max)) is necessary for exercise to elicit positive affective changes. To elucidate this discrepancy, the affective responses to increasing levels of exercise intensity were examined. DESIGN: In total, 30 volunteers rated their affect every minute as they ran on a treadmill while the speed and grade were progressively increased. METHOD: The methodology was unique in three respects: (1) affect was assessed in terms of the dimensions of the circumplex model instead of distinct affective states, (2) affect was assessed repeatedly before, during, and after exercise, not only before and after, and (3) exercise intensity was standardized across participants in terms of metabolically comparable phases (beginning, ventilatory threshold, VO(2max)) instead of percentages of maximal capacity. RESULTS: Pre-to-post-exercise comparisons indicated affective benefits in the form of increased energetic arousal and decreased tense arousal. During exercise, however, affective valence deteriorated beyond the ventilatory threshold and until VO(2max), a trend that reversed itself instantaneously during cool-down. CONCLUSIONS: Exercise intensity that requires a transition to anaerobic metabolism can have a transient but substantial negative impact on affect and this may, in turn, reduce adherence to exercise programmes.

Pleasure and displeasure from the body: Perspectives from exercise

The affective changes associated with acute exercise have been studied extensively in exercise and health psychology, but not in affective psychology. This paper presents a summary of the relevant findings and a tentative theoretical model. According to this model, affective responses to exercise are jointly influenced by cognitive factors, such as physical self-efficacy, and interoceptive (e.g., muscular or respiratory) cues that reach the affective centres of the brain via subcortical routes. Furthermore, the balance between these two determinants is hypothesised to shift as a function of exercise intensity, with cognitive factors being dominant at low intensities and interoceptive cues gaining salience as intensity approaches the individual's functional limits and the maintenance of a physiological steady-state becomes impossible.

The physical activity, stress and metabolic syndrome triangle: a guide to unfamiliar territory for the obesity researcher

Research aimed at deciphering the aetiology of obesity and the metabolic syndrome remains focused on two behavioural factors, namely diet and physical activity, even though epidemiologic research suggests that these two cornerstones of treatment and prevention account for only a small-to-moderate portion of the variance in these phenotypes. In recent years, this observation has prompted the intensified investigation of the pathogenic potential of factors that extend beyond the traditional concept of energy imbalance and examine the putative causes of this imbalance. Psychosocial stress has emerged as one such factor, raising the need for researchers to be informed about this expansive and complex literature. The purpose of this review is twofold (i) To introduce obesity researchers to fundamental concepts and historically important theoretical developments in the stress field and (ii) To outline the dyadic and triadic interactions between stress, physical activity and the metabolic syndrome. Although the expansion of the research focus to multiple, diverse and interacting putative causal agents will certainly increase the complexity of the research enterprise, this step seems essential for the comprehension and effective response to the continuing rise in the prevalence of obesity and the metabolic syndrome.

Predicting affective responses to exercise using resting EEG frontal asymmetry: does intensity matter?

Affective responses to exercise may be important for improving adherence to regular programs of exercise. The present study sought to determine whether resting frontal EEG asymmetry, an individual difference measure of affective style, is predictive of affective responses to exercise performed at distinct intensities standardized relative to a metabolic landmark (i.e., the ventilatory threshold, VT). Resting EEG was collected from 30 participants and used to predict affective responses following treadmill running at three exercise intensities: below-VT, at-VT, and above-VT. Affect was assessed [via Activation-Deactivation Adjective Check List, yielding measures of Energetic Arousal (EA) and Tense Arousal (TA)] before, immediately following exercise, after 5min cool down, and 10 and 20min post-cool down. Resting mid-frontal asymmetry (F4-F3) significantly predicted EA immediately following below-VT exercise; resting lateral frontal asymmetry (F8-F7) predicted EA at 20min post-cool down. Resting mid-frontal asymmetry predicted in EA immediately following and following cool down in above-VT exercise. As a whole, frontal asymmetry was predictive of affective responses following exercise, namely greater relative left frontal activity predicting lower EA. This was opposite to the predictions of the valenced motivation model, but may provide some support for the motivation direction model. This is based on the fact that low EA could be indicative of approach motivation, especially at higher exercise intensities.