Background. Paired exercise and cognitive training have the potential to enhance cognition by "priming" the brain and upregulating neurotrophins. Methods. Two-site randomized controlled trial. Fifty-two patients >6 months poststroke with concerns about cognitive impairment trained 50 to 70 minutes, 3× week for 10 weeks with 12-week follow-up. Participants were randomized to 1 of 2 physical interventions: Aerobic (>60% VO 2peak using <10% body weight-supported treadmill) or Activity (range of movement and functional tasks). Exercise was paired with 1 of 2 cognitive interventions (computerized dual working memory training [COG] or control computer games [Games]). The primary outcome for the 4 groups (Aerobic + COG, Aerobic + Games, Activity + COG, and Activity + Games) was fluid intelligence measured using Raven's Progressive Matrices Test administered at baseline, posttraining, and 3-month follow-up. Serum neurotrophins collected at one site (N = 30) included brain-derived neurotrophic factor (BDNF) at rest (BDNF resting) and after a graded exercise test (BDNF response) and insulin-like growth factor-1 at the same timepoints (IGF-1 rest , IGF-1 response). Results. At follow-up, fluid intelligence scores significantly improved compared to baseline in the Aerobic + COG and Activity + COG groups; however, only the Aerobic + COG group was significantly different (+47.8%) from control (Activity + Games −8.5%). Greater IGF-1 response at baseline predicted 40% of the variance in cognitive improvement. There was no effect of the interventions on BDNF resting or BDNF response ; nor was BDNF predictive of the outcome. Conclusions. Aerobic exercise combined with cognitive training improved fluid intelligence by almost 50% in patients >6 months poststroke. Participants with more robust improvements in cognition were able to upregulate higher levels of serum IGF-1 suggesting that this neurotrophin may be involved in behaviorally induced plasticity.

There is moderate quality evidence that the WSTP is a safe intervention that has a clinically meaningful effect on WST/WST-Q capacity scores and some other outcomes. Implications for rehabilitation A systematic review and meta-analysis of 13 randomized controlled trials on a total of 581 participants, using the Wheelchair Skills Training Program (WSTP) as the intervention, found that the WSTP increased Wheelchair Skills Test (WST) and WST Questionnaire (WST-Q) total capacity scores by 21.2% relative to baseline. Subgroup analyses showed that training was more effective for new wheelchair users. The WSTP was found to have positive effects on some other outcomes and no serious adverse events were reported. The WSTP warrants cautious implementation in clinical and educational settings.

Motor imagery (MI), the mental rehearsal of motor tasks, has promise as a therapy in post-stroke rehabilitation. The potential effectiveness of MI is attributed to the facilitation of plasticity in numerous brain regions akin to those recruited for physical practice. It is suggested, however, that MI relies more heavily on regions commonly affected post-stroke, including left hemisphere parietal regions involved in visuospatial processes. However, the impact of parietal damage on MI-based skill acquisition that underlies rehabilitation remains unclear. Here, we examine the contribution of the left inferior parietal lobule (IPL) to MI using inhibitory transcranial magnetic stimulation (TMS) and an MI-based implicit sequence learning (ISL) paradigm. Participants (N = 27) completed the MI-based ISL paradigm after receiving continuous theta burst stimulation to the left IPL (TMS), or with the coil angled away from the scalp (sham). Reaction time differences (dRT) and effect sizes between implicit and random sequences assessed success of MI-based learning. Mean dRT for the sham group was 36.1 ± 28.2 ms (d = 0.71). Mean dRT in the TMS group was 7.7 ± 38.5 ms (d = 0.11). These results indicate that inhibition of the left IPL impaired MI-based learning. We conclude that the IPL and likely the visuospatial processes it mediates are critical for MI performance and thus MI-based skill acquisition or learning. Ultimately, these findings have implications for the use of MI in post-stroke rehabilitation.

People with HIV are living longer. However, co-morbidities are often more prevalent and severe than in the general population and have greater impacts on health status. Although compelling evidence exists about the health benefits of exercise in the HIV literature, many people living with HIV tend to be physically inactive. The purpose of this study was to use the Theoretical Domains Framework to investigate the barriers and facilitators to participation in exercise of older people living with HIV. This qualitative study involved in-depth, semi-structured interviews with 12 adults aged 45 years and older recruited from HIV organizations and health centres. Data were analyzed thematically using the Theoretical Domains Framework, and two investigators independently coded transcripts. Six prominent domains were identified from the interviews: Social influences, environmental context and resources, reinforcement, intentions, social and professional role, and knowledge. Themes emerging from the interviews fit into all 14 domains of the Theoretical Domains Framework, and 67% of themes fit into the six most prominent domains. The participants had a working knowledge of exercise and its health benefits but were unfamiliar with specific exercise parameters. The majority identified environmental or resource constraints as salient barriers for participation in exercise programmes. Co-morbidities, injuries, and the side effects of HIV disease and medication were also acknowledged as barriers. Stigma and discrimination from friends, family, people within the LGBTQ community, and health care providers were commonly discussed. Participants spoke of the importance of social support to facilitate participation in exercise programmes. Other facilitators included using technology and incorporating exercise into day-to-day activities. People aging with HIV experience many barriers to exercise. Those designing exercise interventions for people aging with HIV should incorporate strategies to address these obstacles.

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