14.2: Is Mindful Movement Motivating?
- Page ID
- 112071
\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
\( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)
\( \newcommand{\dsum}{\displaystyle\sum\limits} \)
\( \newcommand{\dint}{\displaystyle\int\limits} \)
\( \newcommand{\dlim}{\displaystyle\lim\limits} \)
\( \newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\)
( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\)
\( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\)
\( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\)
\( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\)
\( \newcommand{\Span}{\mathrm{span}}\)
\( \newcommand{\id}{\mathrm{id}}\)
\( \newcommand{\Span}{\mathrm{span}}\)
\( \newcommand{\kernel}{\mathrm{null}\,}\)
\( \newcommand{\range}{\mathrm{range}\,}\)
\( \newcommand{\RealPart}{\mathrm{Re}}\)
\( \newcommand{\ImaginaryPart}{\mathrm{Im}}\)
\( \newcommand{\Argument}{\mathrm{Arg}}\)
\( \newcommand{\norm}[1]{\| #1 \|}\)
\( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\)
\( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\AA}{\unicode[.8,0]{x212B}}\)
\( \newcommand{\vectorA}[1]{\vec{#1}} % arrow\)
\( \newcommand{\vectorAt}[1]{\vec{\text{#1}}} % arrow\)
\( \newcommand{\vectorB}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
\( \newcommand{\vectorC}[1]{\textbf{#1}} \)
\( \newcommand{\vectorD}[1]{\overrightarrow{#1}} \)
\( \newcommand{\vectorDt}[1]{\overrightarrow{\text{#1}}} \)
\( \newcommand{\vectE}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash{\mathbf {#1}}}} \)
\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
\(\newcommand{\longvect}{\overrightarrow}\)
\( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)
\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)Although mindful movement is not new, we are just now documenting the many benefits of the practice of mindful movement related to physical activity motivation and behavior. As research is catching up with the practice, we are seeing more and more evidence to support how mindful movement can play a role in motivational processes. As a research topic, mindfulness and motivation is in its infancy. However, there is at least one theoretical model that incorporated mindfulness within a broader description of motivation and well-being more than forty years ago. Self-determination theory (SDT; Ryan & Deci, 2017) is one of the most widely used theoretical frameworks on motivation and well-being across many disciplines and domains. SDT is referred to as a macro-theory, which means that it is a framework that is intended to be applied across all people and domains to holistically describe, explain, and make predictions about human well-being. Below is an overview of key aspects of SDT that are most relevant to mindfulness.
14.2.1. Key Details of Self-Determination Theory Explained
To understand how mindfulness might play a role in motivational processes, it is helpful to understand how motivation is conceptualized within SDT (see Ryan & Deci, 2017; Chapter 3, Quested et al., 2021). Motivation is described as multi-dimensional, reflecting the different ways we regulate our behavior. There are different types of motivation that represent different reasons why people engage in a particular behavior. The focus is on the underlying reasons that energize or regulate behavior and these reasons are presented as falling along a continuum ranging from volitional or autonomous reasons to externally controlling reasons. Amotivation reflects lacking a reason for doing an activity and represents an absence of autonomy. Theoretically, individuals who are amotivated may be acting rather mindlessly given the unintentional nature of their behavior. On the other hand, intrinsic motivation represents the highest degree of autonomy. Intrinsic motivation represents engaging in a behavior, such as exercise, for the rewards gained solely from the act of exercising. These rewards that are inherent to the activity itself can include enjoyment, satisfaction, and challenge, among others. This type of motivation represents the purest form of motivation because it is completely self-regulated (autonomous) and derived from the activity itself; for example, “I exercise because I enjoy the feeling of the movement”. Intrinsic motivation naturally aligns with a mindful state as one is paying attention to the experience itself.
In the middle of the continuum, there are four types of motivation regulations that represent engaging in a behavior for reasons that emanate from sources external to the activity. Each of these types of extrinsic motivation represent progressively lower degrees of autonomy. The external and controlling nature of these types of motivation reflect potential barriers to being present and accepting of one’s experience. The most autonomous of the extrinsic regulations is integrated regulation, which represents an integration of the activity as congruent with one’s sense of self or identity; “I exercise because I identify as a healthy and active person”. Next is identified regulation, which is still autonomous because it represents engaging in a behavior because it is of personal value and importance; “I value the benefits of exercise”. A somewhat more external and more controlling regulation is introjected regulation, which reflects internalized rewards, pressure or guilt; “I exercise because I feel bad about myself if I don’t”. Finally, the most controlling form of motivation, external regulation, represents external rewards or punishments; “I exercise because my physician tells me I have to”. The distinctions between the different types of behavioral regulations highlight the varying degrees of autonomy and external control. The process by which a behavior can become internalized or integrated within an individual’s sense of self and consistent with one’s values is where mindfulness may play a role in motivation.
There is substantial support linking autonomous motivation, and intrinsic motivation in particular, with long-term physical activity behavior (Teixeira et al., 2012). Teixeira et al. conducted a systematic review analyzing the results of 66 studies with a consistent trend across studies that supported the important theoretical connection between intrinsic motivation and sustained physical activity behavior. What this evidence shows is that the most effective and consistent ways to sustain physical activity behavior are to internalize the behavior to be consistent with one’s sense of self and one’s values and to fully enjoy the experience of being physically active. Conceptually, such experiences are consistent with being mindful. SDT outlines that there are ways to support the internalization process to shift more controlling regulations to become more autonomous. A vast amount of research has addressed the role that social and contextual factors (e.g., coaches, exercise instructors) play in supporting or undermining autonomous regulations, with an emphasis on ways that basic psychological needs are fulfilled. Feeling competent, autonomous, and socially related are core psychological needs that lead to optimal psychological functioning and serve as a primary mediator between social influences and autonomous motivation and psychological well-being more broadly (Ryan & Deci, 2017). We know quite a bit about the types of behaviors of significant others that support or undermine psychological needs and impact physical activity motivation. However, there are other ways that psychological needs, and autonomous motivation are fulfilled. Mindfulness is an intra-individual factor that may provide a different type of pathway to psychological need fulfillment.
14.2.2. Theoretical Explanation for the Role of Mindfulness
While there are important inter-personal influences such as the exercise instructor and environment on these motivational processes, there are also intra-personal factors involved. Intra-personal factors are those that are within the individual. Mindfulness represents an understudied, but conceptually supported intra-personal process to consider in physical activity motivation (Brown & Ryan, 2003). In 1980, Deci and Ryan described how mindfulness may play a key role in the internalization process to support autonomous motivation. Let’s start with what it looks like to be mindless from a motivation perspective. Mindlessness represents a mode of operating in reactive, compulsive, and/or habitual patterns. This means that there is no space, intention, or thought behind the action, hallmarks of amotivation and a state with potentially negative consequences. A few examples demonstrate how an absence of mindfulness is reflected in common behavior patterns. For example, experiencing a state of heightened stress may fuel a habit of scrolling distractedly through one’s phone rather than following through with a planned workout. Or feeling shame when one evaluates the shape of their body in the mirror may similarly fuel a cycle of overeating rather than showing up to the gym. These patterns of behavior demonstrate a submission to negative psychological and emotional states and may interrupt acting from one’s core values and needs. Mindful awareness may defend against defensive or ego-involved states, which are more aligned with controlling forms of motivation that are regulated by short-term internal or external rewards and punishments (Ryan & Deci, 2017).

Photo by Artem Beliaikin from Pexels
When acting mindlessly (e.g., compulsive, reactive), there is a lack of space between stimulus and response (e.g., feel bad—skip workout) and no conscious thought for long term consequences. In this state individuals lack intention and connection with values and goals, which are more representative of amotivation or low autonomy (Deci et al., 2015). We have all been there before and it is frustrating to know you should exercise, you want to exercise regularly, but you just can’t break the pattern of inactivity. The result is that we tend to feel bad about ourselves and we don’t reap the mental or physical benefits of exercising. The desires, goals, and value of exercising may not be aligned with the behavioral patterns. This is the place where being more mindful may be helpful for facilitating more autonomous motivation.
Deci and Ryan (1980) argued that the qualities of mindfulness create the psychological space for individuals to make decisions that are more in line with their values, needs, and interests. Mindfulness encompasses qualities of open, attentive awareness of thoughts and feelings (both mental and physical) providing an important first step towards aligning goals, values, and needs with behavior. Attentiveness to one’s needs (i.e., competence, autonomy, relatedness), especially when done with openness, acceptance, and nonjudgment, provides the space to identify, evaluate, and select behavior options more autonomously. Nonjudgmental awareness can, for example, open the door to constructive feedback to inform competence (ability) perceptions and avoid eliciting defensiveness, suppression, or avoidance. Mindfulness qualities can also help to regulate emotional responses by diffusing the reactiveness and compulsiveness that leads to or is fueled by more controlling forms of motivation regulation. In this way, mindfulness creates a pause, a space within which to be more deliberate. The result of this psychological space is that behavioral choices can be made with more clarity and over time can facilitate the internalization process and lead to autonomous motivation and long-term behavior.
14.2.3. Moving Beyond Theory: What Does the Research Show?
The conceptual description of the role of mindfulness in motivational processes is clearly outlined within the assumptions of SDT. Being mindful should facilitate the three core psychological needs which will then support autonomous motivation and physical activity behavior. If you go through your day attending to present-moment thoughts and sensations with an open attitude and allow each experience to emerge, you are more likely to feel in tune with your needs and volitional in what you are doing. This has been demonstrated in a daily diary study showing that those with higher trait mindfulness tend to have more experiences of state mindfulness during daily life and that these individuals report positive affect and more autonomous regulation for their activities (Brown & Ryan, 2003). A key finding of this study was that the state, or moment to moment, experiences of mindfulness had a stronger effect on affect and autonomous motivation and were independent of trait mindfulness. That is, having trait mindfulness tends to lead to more state mindfulness experiences, but trait mindfulness was not necessary for individuals to have state mindfulness experiences. This work provides foundational evidence demonstrating the distinct role of state experiences of mindfulness for predicting more positive affect and more autonomous regulation of behavior.
Research evidence illustrates the relationships of both trait and state mindfulness with psychological need satisfaction and autonomous motivation for exercise. Trait mindfulness has been positively associated with autonomous motivation for physical activity and negatively associated with controlling forms of motivation for physical activity (Kang et al., 2017; Ruffault et al., 2016). These findings have been based on cross-sectional research and have been of small magnitude. There is some evidence that having high trait mindfulness can strengthen the relationship between intrinsic motivation and physical activity behavior (Ruffault et al., 2016). This supports the conceptualization of mindfulness as a facilitator of internalization processes and alignment of values with behaviors. However, there is very limited exploration into these processes and trait mindfulness appears to have a relatively small impact on behavior.
An alternative approach, drawing from Brown and Ryan’s (2003) work, is to focus on how the specific experiences of being mindful plays a role in physical activity motivation and behavior. If an individual experiences movement mindfully (i.e., state mindfulness), then they may feel more connected to their body and the experience of moving which may provide the opportunity to feel more empowered and satisfied with the movement itself. Conceptually, it seems then that state mindfulness is aligned with intrinsic motivation which is derived from the very experience of moving.
Greater awareness of one’s feelings and sensations during movement may increase one’s ability to meet their needs for competence, autonomy, and relatedness, thus facilitating the internalization process toward autonomous regulation. Mindfulness allows attention without judgment that can serve to connect one to their physical experience, which should raise perceptions of competence and foster their sense of autonomy. Imagine a high-intensity spin class where legs are burning, sweat dripping, and lungs screaming. Paying attention to these sensations without judgement allows one to better respond with what supports one’s goals. For the hardcore athlete, these cues align with fitness goals and give biofeedback about performance that guides effort. For someone just starting their fitness journey, these sensations may be an indicator of overexertion which may not serve the longer-term goal of sticking with a new fitness routine. Mindful attention will aid the athlete to push themselves while directing the inexperienced spinner to pace themselves so they can finish the session and return for another day. When an exercise session is uncomfortable, a mindful approach can allow an individual to view behavioral options with more clarity and be more volitional about how to proceed in a way that also supports feelings of autonomy. There is some evidence to support this pathway. We examined state mindfulness, psychological needs (perceived competence and autonomy), and autonomous motivation for physical activity longitudinally across a 16-week yoga class (Cox, Ullrich-French, & Austin, 2020). We found that trait mindfulness predicted state mindfulness, but not psychological needs or motivation. Participants who started the yoga class with higher state mindfulness and those that increased in their experiences of state mindfulness across the 16 weeks reported increases in perceived competence and autonomy. In addition, growth in state mindfulness directly and indirectly (through need satisfaction) predicted autonomous motivation for physical activity. This study is the first to test a SDT-based process model of the role of trait and state mindfulness in physical activity motivation. This evidence supports the conceptual links laid out about how mindful movement can serve to facilitate autonomous motivation and suggests that indeed, mindful movement can be motivating.
You are in a high-intensity exercise class that is pushing you to your limit. You have choices. If you value and are motivated to push yourself then your response might be “bring it on”. If you value overall wellness, and want to survive to return to another class, your response might be “how can I modify this so I can complete the class?”. What are the ways that you might respond in this moment (i.e., emotionally and behaviorally)? Think about what is driving that response. Does the response align with your motivation, goals, and values? Does your response help you feel more competent and autonomous?
14.2.4. Other Important Motivational Factors: How Pleasant is Moving?
Strategies for increasing motivation to exercise need to consider the vital role of how people feel while exercising. The degree to which exercise is experienced as pleasant in the moment, referred to as core affect, is a good predictor of future behavior (Brand & Ekakakis, 2018; see also Chapter 4, Brand & Ekkekakis, 2021). We are more motivated to repeat pleasant rather than unpleasant activities,right? The extent to which exercise has pleasant feelings associated with it, the greater the likelihood of choosing to exercise again in the future and making that choice for intrinsic reasons. State mindfulness has been found to positively associate with positive affect across a range of daily activities (Brown & Ryan, 2003). That is, generally things are more pleasant when engaging in them mindfully. Being mindful may allow for a more balanced emotional state, which is a generally pleasant psychological state of equanimity, peacefulness, or contentedness. Someone completing a challenging exercise mindfully may be able to hold the negative physiological sensations in balance with feelings of satisfaction to maintain an adaptive psychological state.
In order to develop useful exercise interventions, a growing trend is to focus on how to make exercise experiences more pleasant. Many people exercise with distraction, such as listening to music, as a coping strategy to “get through it” or so they “don’t feel the pain”. Dissociative strategies, such as listening to music during exercise have been touted as a way to make exercise more pleasant. Although music is an effective strategy for making individual exercise sessions more pleasant, we have some evidence to suggest that intentionally manipulating mindfulness while exercising can lead to similarly pleasant exercise experiences as listening to music while exercising (Cox, Ullrich-French, Hargreaves, & McMahon, 2020). This suggests that paying attention to the physical experience of moving your body can be pleasant and comparable to listening to music. Although dissociation may serve a purpose of reducing awareness of discomfort and is motivating for many people, this can lead to a dissociation with the bodily experience of moving. While a distracted experience tends to be enjoyable, it should be more difficult to develop a strong sense of competence when one isn’t fully experiencing the movement and activity itself. Thus, a dissociative focus during exercise is less likely to lead to the fulfillment of basic psychological needs and the long-term adherence through autonomous motivation. We have a lot to learn still about how to effectively apply mindfulness strategies to lead to optimal exercise experiences.
When you exercise to music it makes the time go by, it can be motivating and fun. Think about your experiences exercising with and without music. When you finish a workout while listening to music, how much of the experience to you remember? How connected do you feel with the sensations in your body? Your feelings of competence or achievement? Now, what about when you don’t listen to music? How does the experience differ?
14.2.5. Moving from Motivation to Behavior: Mindfulness and Physical Activity Behavior
As discussed previously, mindful forms of movement have been linked to a variety of health behaviors. Similarly, trait mindfulness and physical activity behavior have been connected in several different ways. Those who self-report more physical activity also report higher levels of trait mindfulness (Gilbert & Waltz, 2010; Kangasniemi et al., 2014) and are more likely to engage in mindfulness practices (Strowger et al., 2018). The type of activity may be important though, as time spent doing intentionally mindful activities such as yoga are associated with higher trait mindfulness while time spent doing cardio-based exercise has been associated with lower trait mindfulness (Martin et al., 2013). This indicates that qualities of the physical activity are relevant to the role of mindfulness. It could be either that those who are generally more mindful gravitate towards mindful movement (e.g., yoga) or that the mindful movement develops the tendency to be mindful. There is not enough information to know if there is one direction of influence, although both possibilities are likely working together to mutually reinforce one another.
An added complication to the puzzle of understanding the role of mindfulness in physical activity behavior is that although there is a consistent positive association between mindfulness and self-reported physical activity, this is not the case when physical activity is assessed more objectively (e.g., accelerometer based assessment of movement; Kang et al., 2017; Kangasniemi et al., 2015). In addition, when mindfulness is context specific, or applied specifically to physical activity, it is more strongly and consistently associated with physical activity compared to trait mindfulness. So, the context matters in several ways. One can be mindful generally, but not in a specific physical activity experience. For example, someone who generally is mindful can have a bad day and be distracted during a workout. Or, someone who isn’t generally mindful can show a special interest in a physical activity and have more focus, attention, and connection while doing that activity than in other areas of their life. It is difficult to predict and understand all the factors that influence behavioral choices, but we do know that mindfulness is related to many of those factors including more autonomous motivation, positive affect, and other physical activity related perceptions (e.g., psychological needs). The relationship between mindfulness and physical activity behavior is likely indirect and the more we can uncover about the processes that might link the two, the better we can understand the role of mindfulness in motivation.
14.2.6. Mindfulness as an Intervention to Increase Physical Activity
Mindfulness interventions often include acceptance and mindfulness-based stress reduction approaches that teach and then facilitate the practice of mindfulness strategies. Acceptance, compassion, and mindfulness approaches share the promotion of awareness and nonjudgement toward the self. Such approaches have led to increases in physical activity (e.g., Butryn et al., 2011; Palmeira et al., 2017). In one intervention, college age women were assigned to either an educational condition or an Acceptance and Commitment Therapy (ACT) condition aimed to increase physical activity (Butryn et al., 2011). The educational condition provided information about the benefits of physical activity and ways to safely participate in physical activity. Participants in the ACT condition were taught how to defuse or separate from distressing thoughts about exercise and identify and strengthen values around exercise. Post-intervention and at a three-week follow-up, participants in the ACT condition participated in more physical activity compared to participants in the education condition. This study shows how developing mindfulness skills and using strategies to address intrinsic motivation (aligned with SDT) were effective at increasing physical activity behavior. Although this intervention targeted physical activity behavior and interventions were physical activity based in content, there was not an explicit movement component that was manipulated. Applications of mindfulness in school interventions also show that physical activity can be increased in children (Salmoirago-Blotcher at al., 2018). However, children who started this intervention with higher levels of activity showed a stronger effect of the mindfulness training. Perhaps this means that having experience with physical activity primes individuals or allows them to more easily apply mindfulness in an adaptive way. In a randomized controlled trial with healthy adults that used physical activity as a comparison group, similar amounts of physical activity were found for the MBSR and aerobic exercise conditions (Meyer et al., 2018). This study concludes that the real benefit may be in combining MBSR with physical activity. There is still much to be learned about how to most effectively incorporate mindfulness into physical activity interventions.


