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When Physical Activity Is Valued but Participation Feels Out of Reach: Barriers, Perceived Behavioural Control and Physical Activity Intentions among People Experiencing Homelessness

This study of 102 adults experiencing homelessness in Greece and Italy reveals that while perceived barriers negatively impact physical activity intentions, Perceived Behavioural Control (PBC) serves as the critical independent predictor of intention, suggesting that initiatives must address practical feasibility within existing circumstances rather than relying solely on motivation.

Original authors: Fotis Panagiotounis

Published 2026-10-07

📖 5 min read🧠 Deep dive

CC BY 4.0

Original authors: Fotis Panagiotounis

Original paper licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). ✨ This is an AI-generated explanation of the paper below. It is not written or endorsed by the authors. For technical accuracy, refer to the original paper. Read full disclaimer

Imagine trying to run a marathon when you do not know where you will sleep tonight, when your next meal will arrive, or if you have a safe place to rest your head. For the millions of people around the world who experience homelessness, the simple act of exercising is often overshadowed by the immediate, crushing weight of survival. While doctors and public health experts have long known that moving the body brings immense benefits to both physical health and mental well-being, these advantages often remain out of reach for those without a stable home. The question is not whether these individuals want to be healthy or if they value exercise; rather, it is about whether their daily reality makes the idea of participating in physical activity feel like a realistic possibility.

To understand this gap between wanting to act and actually being able to act, researchers often look at two main ideas. The first is the concept of barriers, which are the practical obstacles people face, such as a lack of money for shoes, no transportation to a gym, or the sheer exhaustion that comes from struggling to find food and shelter. The second idea is about control, or the feeling that one has the power to make something happen. In the world of behavioral science, this is often called perceived behavioral control. It is the internal judgment a person makes about whether a task is doable given their current circumstances. When a person feels that the obstacles are too high, their sense of control drops, and even if they have the desire to move, the intention to do so fades away.

A recent study conducted in Greece and Italy sought to explore exactly how these feelings of control and the presence of barriers interact among people experiencing homelessness. The researchers gathered a group of 102 adults who were either living on the streets, in shelters, or in unstable housing situations. These participants came from community centers and day services, representing a mix of men and women with varying levels of health challenges and social support. The team asked them a series of questions about their lives, their health, and their thoughts on physical activity. They specifically wanted to know what the participants saw as the biggest hurdles, how capable they felt they were to exercise, what opportunities they thought were available to them, and how much control they felt they had over making it happen.

The results painted a clear picture of the struggle. The study found that when people perceived more barriers—whether financial, logistical, or related to safety and health—their intention to participate in physical activity dropped significantly. It was not just that they felt less capable or that they saw fewer opportunities; the barriers seemed to erode their entire sense of control. When the researchers looked at the data closely, they discovered that while having the physical ability and seeing opportunities in the environment were important, the single strongest predictor of whether someone intended to exercise was their feeling of control. In other words, a person might have the energy and a park nearby, but if they do not feel that the situation allows them to actually use those resources, they will not plan to go.

This finding suggests that the problem is not a lack of motivation or a failure of will. Instead, the intention to exercise is deeply tied to the practical reality of a person's life. The study showed that when the feeling of control was taken into account, the direct influence of other factors, like general capability or the presence of opportunities, became less significant. This implies that the feeling of control acts as a final gatekeeper. It is the moment where a person weighs their internal resources against the external world and decides if the effort is worth it. If the environment feels too hostile or unpredictable, the sense of control vanishes, and with it, the plan to move.

The researchers were careful to note that this study looked at what people intended to do, not necessarily what they actually did, and that the data came from a relatively small group. However, the pattern was strong enough to suggest a vital lesson for anyone trying to help. Simply telling people to exercise or trying to boost their confidence is not enough if the practical conditions of their lives remain unchanged. The study indicates that for physical activity to become a reality for people experiencing homelessness, the focus must shift from the individual to the environment. Programs need to be designed in a way that removes the practical hurdles—providing transport, flexible schedules, safe spaces, and supportive relationships—so that the feeling of control can return. Only when the path feels clear and manageable will the intention to move translate into the action of moving.

Technical Summary: Barriers, Perceived Behavioural Control, and Physical Activity Intentions among People Experiencing Homelessness

Problem Statement
Physical activity offers potential health and social benefits for people experiencing homelessness, yet participation remains constrained by material, social, and organisational conditions. While existing literature documents the benefits of sport and the barriers to engagement (e.g., financial constraints, unstable accommodation, safety concerns), there is a gap in understanding how these contextual constraints translate into behavioural readiness. Specifically, it is unclear whether the "participation gap" is driven primarily by a lack of motivation or by a perception that participation is not realistically feasible within existing circumstances. This study addresses this gap by examining the associations between perceived barriers, COM-B constructs (Capability and Opportunity), Perceived Behavioural Control (PBC), and behavioural intention to participate in physical activity among adults experiencing homelessness or housing instability.

Methodology

Design: A cross-sectional study utilizing hierarchical regression and parallel indirect-effects analysis.
Participants: 102 adults experiencing homelessness or housing instability recruited through community-based services in Greece (an NGO day center) and Italy (a community shelter). Eligibility followed the European Typology of Homelessness and Housing Exclusion (ETHOS), encompassing rooflessness, temporary accommodation, and severe housing exclusion. The sample was predominantly male (78.4%) with a mean age of 53.99 years.
Measures:
- Perceived Barriers: A 14-item context-adapted measure based on the Exercise Benefits/Barriers Scale (EBBS), assessing constraints such as transportation, finances, scheduling, and safety.
- Theory of Planned Behaviour (TPB) Constructs: Attitude, Subjective Norm, Perceived Behavioural Control (PBC), and Behavioural Intention (operationalized as readiness rather than actual behavior).
- COM-B Constructs: Capability (physical/psychological capacity), Opportunity (external conditions), and Motivation.
- Scoring: All constructs used 7-point response scales. Measures were context-adapted for the target population; internal consistency was assessed (Cronbach's $\alpha$ ranged from .76 to .95).
Analysis:
- Hierarchical multiple regression examined the incremental contribution of perceived barriers, Capability, Opportunity, and PBC to behavioural intention.
- Parallel indirect-effects analysis (PROCESS Model 4) tested whether Capability, Opportunity, and PBC mediated the relationship between perceived barriers and intention.

Key Results

Bivariate Associations: Greater perceived barriers were significantly associated with lower behavioural intention, lower Capability, lower Opportunity, and lower PBC. At the bivariate level, Capability, Opportunity, and PBC were all positively associated with intention. PBC exhibited the strongest correlation with intention ( $r = .67$ ).
Hierarchical Regression:
- Step 1: Recruitment context explained a small but significant portion of variance.
- Step 2: Adding Perceived Barriers significantly improved the model ( $\Delta R^2 = .083$ ); greater barriers predicted lower intention.
- Step 3: Adding Capability and Opportunity further improved the model ( $\Delta R^2 = .116$ ). Capability was independently associated with intention, while Opportunity was not. At this stage, Perceived Barriers became non-significant.
- Step 4: Adding PBC produced the largest incremental improvement ( $\Delta R^2 = .259$ ). In the fully adjusted model, PBC was the only behavioural construct independently associated with intention ( $\beta = .678$ ). Perceived Barriers, Capability, and Opportunity were no longer significant predictors. The final model explained approximately 49.7% of the variance in intention.
Mediation Analysis:
- Perceived barriers were negatively associated with all three mediators (PBC, Opportunity, Capability).
- When considered simultaneously, only the indirect path through PBC was statistically significant. The indirect effects through Opportunity and Capability were not supported.
- The total indirect effect of barriers on intention was significant and attributable specifically to PBC. The direct effect of barriers on intention became non-significant after including the mediators.

Key Contributions and Claims
The paper posits that behavioural readiness for physical activity among people experiencing homelessness depends less on motivation alone and more on the perceived feasibility of participation within existing circumstances.

Theoretical Distinction: The study distinguishes between Capability and Opportunity (descriptive conditions) and PBC (a proximal appraisal of control). The findings suggest that while barriers reduce Capability and Opportunity, it is the resulting reduction in PBC that most directly drives the reduction in behavioural intention.
Contextual Appraisal: PBC is conceptualized not merely as an individual psychological trait but as a "proximal appraisal of feasibility at the person–environment interface." It reflects how individuals judge whether participation is manageable given material, social, and organisational constraints.
Measurement Overlap: The author acknowledges a conceptual and measurement overlap between Capability and PBC (both include perceptions of ability/capacity), which likely explains why Capability's independent effect was attenuated when PBC was introduced. However, PBC accounted for unique variance in intention.

Significance and Implications

Practical Implications: The author argues that interventions should shift focus from solely motivating individuals to creating environments where participation is perceived as feasible. This involves addressing practical barriers (cost, transport, scheduling), social barriers (stigma, belonging), and organisational barriers (service accessibility).
Program Design: Physical activity initiatives should be low-threshold, flexible, and context-responsive. Supportive facilitator relationships and non-judgmental environments are highlighted as critical for making participation feel safe and achievable.
Modesty of Claims: The paper explicitly states that these findings represent an "initial explanatory test" due to the modest sample size, the cross-sectional design (limiting causal inference), and the use of context-adapted measures that have not undergone formal psychometric validation. The author cautions that the study examines intention (readiness) rather than actual behavior, noting that favorable intentions may not translate to action without sufficient actual control over resources and routines.
Future Research: The author calls for prospective studies to track the transition from readiness to actual participation and intervention studies to test whether modifying participation conditions alters PBC and behavior. They also note the need for larger samples to distinguish service-level effects from national differences, as recruitment sites were confounded with country.

Technical Summary: Barriers, Perceived Behavioural Control, and Physical Activity Intentions among People Experiencing Homelessness

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