Dual-Mode Theory (DMT)

There is a complex relationship between the intensity of exercise and affective responses. During and for a short period following moderate-intensity exercise, most people respond positively. During exercise performed at an intensity that approximates the gas exchange ventilatory threshold, there is considerable variability from individual to individual, with some responding positively and others responding negatively. These differences can be accounted for to some degree by individual differences in preference for and tolerance of the somatic sensations associated with vigorous exercise, as well as by differences in cognitive factors, such as self-efficacy. Beyond the gas exchange ventilatory threshold, where a physiological steady-state can no longer be maintained, there is a near-universal decline in the valence of affective responses. At this level, ratings of affective valence (positivity versus negativity) are primarily correlated with physiological parameters (i.e., ventilation, blood lactate).

The guiding conceptual framework of this research is the dual-mode theory of exercise-induced affective responses. According to this theory, affective responses to exercise are jointly influenced by two coacting factors, namely cognitive factors, such as physical self-efficacy, and interoceptive (e.g., muscular or respiratory) cues that reach the affective centers of the brain via subcortical routes. The balance between these two determinants is hypothesized to shift systematically as a function of exercise intensity, with the 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.

Dual-Mode Theory 1
The predicted pattern of affective valence responses (pleasure vs. displeasure) across the three domains of exercise intensity (moderate, heavy, severe) according to the Dual-Mode Theory. Affective responses are predicted to be mostly positive in the moderate domain, heterogeneous in the heavy domain, and homogeneously negative in the severe domain. 


Dual-Mode Theory 2
According to Dual-Mode Theory, the variance in affective responses is accounted for by cognitive factors in the moderate and (mainly) the heavy domain of exercise intensity but primarily by interoceptive factors in the severe range of intensity. 




The Dual-Mode Theory assumes that the range of exercise intensity consists of three domains that reflect differences in underlying metabolic processes and oxygen uptake kinetics. The three domains are delimited by three landmarks: (a) the lactate threshold (LT), (b) the level of critical power (CP) or maximal lactate steady state (MLSS), and (c) maximal oxygen uptake. In our research, we use the gas-exchange ventilatory threshold (VT) and the Respiratory Compensation Point (RCP) as less invasive approximations of the LT and the CP/MLSS, respectively. 

Importantly, each domain of intensity has distinct adaptational implications and is characterized by a distinct pattern of affective changes, consistent with the assumption of Dual-Mode Theory that affect is closely tied to homeostatic regulation. 

Dual-Mode Theory 3
The Dual-Mode Theory assumes that the range of exercise intensity is divided in three domains: (a) moderate (up to the lactate threshold), (b) heavy (from the lactate threshold to the level of critical power or maximal lactate steady state), and (c) severe (from critical power or maximal lactate steady state to peak oxygen uptake). In this example from a typical non-athletic middle-aged individual, the lactate threshold is approximated by the gas-exchange ventilatory threshold (VT, here occurring at 48% of peak oxygen uptake) and the critical power / maximal lactate steady state is approximated by the Respiratory Compensation Point (RCP, here occurring at 81% of peak oxygen uptake). 


The first domain, termed the domain of moderate exercise, includes the intensities up to the LT (i.e., the exercise intensity at which blood lactate accumulation starts to exceed baseline values, as the rate of production from working muscles exceeds the rate of clearance) or VT (i.e., the exercise intensity at which the volume of carbon dioxide produced starts to exceed the volume of oxygen consumed). 

In the moderate domain, affective responses either remain positive or are further improved for most healthy individuals. The potential for this range to generate positive affective experiences appears to be further enhanced if the intensity is self-regulated, as in a self-paced walk. This prediction is supported by empirical data on samples of healthy young, middle-aged, and older adults. However, among low-active individuals with obesity, weight-bearing activity such as walking, even exercise within the moderate domain of intensity has been found to lead to declines in affective valence.

Dual-Mode Theory 4
In the moderate domain of intensity (up to LT/VT), the Dual-Mode Theory predicts that most individuals will either continue to report positive ratings of affective valence or will report improvements in affective valence.


The second domain of intensity, termed the domain of heavy exercise, extends from the LT/VT to CP/MLSS. The CP/MLSS typically occurs at 70-80% of maximal heart rate or 60-70% of maximal oxygen uptake in nonathletic adults. In this domain, given sufficient duration, the rate of lactate clearance can "catch up" with the rate of production, leading to a restabilization of lactate concentration over time. This again allows the establishment of a physiological steady-state but at a higher level of lactate and oxygen uptake than the steady-state attained in the moderate domain. This is due to the appearance of a "slow component" of oxygen uptake, reflecting a loss of muscle efficiency. Exercise within the heavy domain cannot be continued indefinitely. If the upper boundary of this domain is exceeded, lactate will continue to rise. Thus, the upper boundary of this domain is also termed the "maximal lactate steady-state" (MLSS).

The domain of heavy exercise intensity is characterized by interindividual variability in affective responses, with some individuals reporting improvements and others reporting declines in affective valence. This heterogeneity may be associated with the ambiguous adaptational implications of exercise at this range of intensity. On the one hand, exercise within this range may entail adaptational advantages (e.g., covering longer distances in search of subsistence resources, persisting in the pursuit of prey) but, on the other hand, it raises the risk of adverse events (e.g., exhaustion, injury). It should also be emphasized that, while variability is found among participants that represent a wide range of physical activity and fitness levels, most chronically hypoactive adults report declines in affective valence in response to exercise that exceeds the LT/VT.

Dual-Mode Theory 5
In the heavy domain of exercise intensity, the Dual-Mode Theory predicts interindividual variability in affective responses, with some individuals reporting increases in pleasure and others decreases.


The third domain, termed the domain of severe exercise, extends from CP/MLSS to peak oxygen uptake. In this domain, it is no longer possible to maintain a physiological steady state. Physiological parameters, such as oxygen uptake and blood lactate, rise continuously and exercise is terminated within a few minutes.

The domain of severe exercise intensity is characterized by universal declines in affective valence. Although there may be variability in the rate of declinethe direction of change is negative for all individuals. Presumably, this homogeneous decline reflects the unambiguous adaptational implications of exercise in this range of intensity. The severe homeostatic perturbation, the impending metabolic crisis, and the specter of irreparable harm or death necessitate that a clear imperative be communicated to consciousness that the intensity must be immediately reduced or the activity must be stopped.

Dual-Mode Theory 6
In the domain of severe exercise intensity, the Dual-Mode Theory predicts homogeneous declines in affective valence, reflecting the severe homeostatic perturbation. 


The Dual-Mode Theory further postulates that affective responses to exercise are regulated by an extensive network of brain regions that largely overlaps with the network responsible for regulating affective responses to exteroceptive (e.g., visual) affective stimuli (i.e., what Feldman Barrett and coworkers have described as the "affective neural reference space" or "affective workspace," including, but not limited to, the insula, the anterior cingulate, the medial, dorsal, and orbital divisions of the prefrontal cortex, and the ventral striatum). In the affect-regulation literature, neuroimaging evidence suggests that, in the presence of aversive or unpleasant stimuli, increased activity in the (medial and dorsal) prefrontal cortex is typically coupled with attenuated activity in the amygdala, with the increase in prefrontal activity and the decrease in amygdala activity being indicative of effective coping. Accordingly, the Dual-Mode Theory predicts that increased prefrontal activation in the heavy domain of intensity (when the challenge posed by exercise is substantial but not yet overwhelming) would be associated with the maintenance of positive affective valence. In contrast, in the severe domain of intensity (when the challenge posed by exercise becomes overwhelming), decreased prefrontal activation combined with increased activation of the amygdala would account for the observed decline in affective valence.

Dual-Mode Theory neural basis
Ekkekakis and Acevedo (2006) reviewed evidence that interoceptive afferents can reach the amygdala via multiple subcortical routes, potentially allowing the regulation of the amygdala without cortical involvement. This evidence raises the possibility that, perhaps under conditions of severe homeostatic perturbations (e.g., severe-intensity exercise), affective behavior may directly reflect the physiological condition of the body, "unfiltered" by prefrontal networks. 


Dual-Mode Theory neural basis
Ekkekakis (2009) reviewed the literature on the use of Near-Infrared Spectroscopy (NIRS) of the dorsolateral prefrontal cortex and found evidence of reduced prefrontal oxygenation (and, therefore, presumably activation) at severe exercise intensities (especially exceeding the Respiratory Compensation Point). This evidence raises the possibility of the prefrontal cortex lessening its influence within affect-regulation networks when the intensity of exercise approaches one's peak functional capacity. 



The practical implication for exercisers and exercise professionals is that attempts to use cognitive techniques to improve affective responses within the severe domain (e.g., attentional dissociation, boosting self-efficacy, cognitive reframing or reappraisal) would likely be ineffective because the biological substrate of these interventions (i.e., the prefrontal cortex) would be hypoactive.


Recommended Readings on the Dual-Mode Theory

  • Ekkekakis, P., Hartman, M.E., & Ladwig, M.A. (2020). Affective responses to exercise. In G. Tenenbaum & R.C. Eklund (Eds.), Handbook of sport psychology (4th ed., pp. 233-253). New York: Wiley. ISBN: 978-1-119-56807-0 [DOI]
  • Ekkekakis, P., & Brand, R. (2019). Affective responses to and automatic affective valuations of physical activity: Fifty years of progress on the seminal question in exercise psychology. Psychology of Sport and Exercise, 42, 130-137. [DOI