Anxiety-related attentional characteristics and their relation to freezing of gait in people with Parkinson's: Cross-validation of the Adapted Gait Specific Attentional Profile (G-SAP).

The adoption of healthy movement behaviour—being sufficiently physically active and spending less time in sedentary behaviour—is important for the management of symptoms in Parkinson's disease (PD). There is systematic evidence for the beneficial effects of healthy movement behaviour, in conjunction with pharmaceutical treatment, on a wide range of PD motor symptoms, such as gait, balance, musculoskeletal strength and aerobic capacity. In addition to motor symptoms, people with PD exhibit a diverse range of non-motor characteristics, such as mood disorders and cognitive impairment. While these symptoms are known to impact quality of life, they are often under-acknowledged and undertreated. Additionally, relationships between movement behaviour and PD non-motor characteristics are not fully understood. Evidence suggests that healthy movement behaviours relate to decreased levels of depression and anxiety and improved cognition. Among people with PD, physical factors can affect movement behaviour as well as psychological factors. Specifically, self-efficacy for exercise, defined as an individual's belief in their capacity to overcome personal, social, and environmental barriers to physical activity, is recognised as a key factor influencing movement behaviour in PD. An additional influential factor is a person's perceived confidence in their balance. However, current research on the impact of psychological factors on movement behaviours remains limited in PD. In previously published research, specific movement behaviours have generally been examined in isolation, independent of their separate parts. These parts can be defined as light-intensity physical activities (LIPA), moderate-to-vigorous physical activities (MVPA), and sedentary behaviour (SB). However, MVPA, LIPA and SB are interdependent behaviours, such that if time in one behaviour increases, time in one (or several) of the other behaviours must decrease. If, for example, the time a person with PD spends in SB is reallocated to time spent in MVPA, this shift could incur positive effects on health and quality of life. Compositional Data Analysis (CoDA) is a novel method used to analyse movement behaviours as relative to each other, as opposed to the more traditional methods where each behaviour is analysed separately in terms of absolute time. The use of CoDA together with compositional isotemporal substitution analysis allows us to theoretically test the effect of time reallocation across different movement behaviours on specific health outcomes. To our knowledge, this approach has not yet been used in the published literature to characterise movement behaviour in the PD population. People with PD have more unhealthy movement behaviours than healthy older adults, with those in mild to moderate stages of PD spending 75–80% of their waking hours in SB and only 2–3% in MVPA. Motivating and supporting people with PD to engage in healthy movement behaviours is often a main goal of rehabilitation and advice should be person-centred. Precision-based exercise prescription requires a detailed understanding of specific movement behaviours in PD, and how they relate to disease characteristics. However, there is insufficient evidence for the relative benefits of different exercise intensities on health in PD, due to a lack of adequately powered studies. In particular, knowledge concerning the relationships between specific movement behaviours and non-motor characteristics is lacking. Therefore, the aim of this study was to investigate associations between relative time in the movement behaviours MVPA, LIPA and SB, and non-motor characteristics in people with PD, and to investigate the theoretical changes which occur in non-motor characteristics when time in different movement behaviours is reallocated. We hypothesise that more relative time in MVPA and less relative time spent in SB will be associated with higher levels of self-efficacy for exercise and cognition, and lower levels of depression and anxiety. Furthermore, we hypothesise that reallocation of time from SB to MVPA will be associated with similar changes.