Sociodemographic characteristics associated with physical activity barrier perception among manual wheelchair users.

BACKGROUND: Individuals with disabilities are sub-optimally active and at increased risk for chronic diseases. Limited knowledge exists about how differences among wheelchair-dependent individuals may affect their perception of physical activity barriers. OBJECTIVE: We examined whether the perception of physical activity barriers are associated with wheelchair user sociodemographic characteristics. METHODS: Danish manual wheelchair users (MWCUs) (N = 181; 52.5% females, mean ± SD: age 48 ± 14 yrs) completed the 'Barriers to Physical Activity Questionnaire for People with Mobility Impairments' (BPAQ-MI) online. The BPAQ-MI queries physical activity barriers in four domains (intrapersonal, interpersonal, organizational, and community) and eight subdomains. Participant characteristics evaluated as potentially associated with physical activity barriers included age, sex, years in chair, body mass index (BMI), spinal cord injury (SCI) (if any), education, employment, and resident city size. Simple linear regression (step 1) and multiple regression models (step 2) were created to assess associations between MWCU characteristics and barriers. RESULTS: Multiple regression models revealed that MWCUs who were obese, who did not complete high school, or were unemployed rated physical activity barriers higher across several subdomains (all r2≤0.226, p<0.05). Resident city size was associated with safety subdomain barrier impact (r2=0.039, p<0.05). Sex, age, years in chair and SCI were not associated with any barrier domains (all p ≥ 0.064). CONCLUSIONS: Our results provide new evidence that MWCUs with BMI ≥30; who are not employed; or who only have completed high school, may need special consideration and resources to overcome distinct physical activity barriers. Behavioral strategies and interventions focusing on reducing physical activity barriers should be tailored to the individuals above.

Physical Activity Barriers in Danish Manual Wheelchair Users: A Cross-sectional Study.

OBJECTIVE: To identify physical activity barrier prevalence and severity among manual wheelchair users (MWCUs) and test whether barrier impact is associated with self-reported physical activity level (PAL). DESIGN: Cross-sectional survey. The Barriers to Physical Activity Questionnaire for People with Mobility Impairments (BPAQ-MI) was translated from English to Danish and administered online. The BPAQ-MI includes barriers within 4 domains and 8 subdomains and queries if an item hindered physical activity participation in the last 3 months (yes/no). If "yes," participants graded barrier severity from very small (1) to very big (5). Barrier impact scores were summed within and across domains. SETTING: General community. PARTICIPANTS: Danish MWCUs (N=181; 52.5% female, mean age, 48±14y.). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: PAL was rated from not active (1) to extremely active (10). Individual barrier prevalence (frequency, %) and severity (median [interquartile range]) was computed. Unadjusted (Spearman rank correlations, domains, subdomains) and adjusted (multivariate linear regression, subdomains) associations between PAL and barrier impact were computed. RESULTS: The 5 most prevalent barriers were reported by ≥49.6% of participants (2 intrapersonal and 3 community). The 5 most severe barriers all had a median of 5 (1 organizational and 4 community). Unadjusted analysis showed that PAL was inversely associated with total intrapersonal (r=-0.487, P<.01) and overall (r=-0.241, P<.01) impact and the intrapersonal "health" (r=-0.477, P<.01) and "beliefs/attitudes"(r=-0.307, P<.01) subdomains. Adjustment for shared variance revealed only the "health" subdomain impact score was independently associated with PAL (P<.001). CONCLUSIONS: Intrapersonal barriers were highly prevalent. Health-related barriers were inversely related to PAL. When organizational and community barriers were present, they were rated as particularly severe. These results provide novel information that can guide the design of future interventions aiming to increase MWCUs PALs.

CO2 supplementation dissociates cerebral oxygenation and middle cerebral artery blood velocity during maximal cycling.

This study evaluated whether the reduction of prefrontal cortex oxygenation (ScO2 ) during maximal exercise depends on the hyperventilation-induced hypocapnic attenuation of middle cerebral artery blood velocity (MCA Vmean ). Twelve endurance-trained males (age: 25 ± 3 years, height: 183 ± 8 cm, weight: 75 ± 9 kg; mean ± SD) performed in three separate laboratory visits, a maximal oxygen uptake (VO2 max) test, an isocapnic (end-tidal CO2 tension (PetCO2 ) clamped at 40 ± 1 mmHg), and an ambient air controlled-pace constant load high-intensity ergometer cycling to exhaustion, while MCA Vmean (transcranial Doppler ultrasound) and ScO2 (near-infrared spectroscopy) were determined. Duration of exercise (12 min 25 s ± 1 min 18 s) was matched by performing the isocapnic trial first. Pulmonary VO2 was 90 ± 6% versus 93 ± 5% of the maximal value (P = .012) and PetCO2 40 ± 1 versus 34 ± 4 mmHg (P < .05) during the isocapnic and control trials, respectively. During the isocapnic trial MCA Vmean increased by 16 ± 13% until clamping was applied and continued to increase (by 14 ± 28%; P = .017) until the end of exercise, while there was no significant change during the control trial (P = .071). In contrast, ScO2 decreased similarly in both trials (-3.2 ± 5.1% and -4.1 ± 9.6%; P < .001, isocapnic and control, respectively) at exhaustion. The reduction in prefrontal cortex oxygenation during maximal exercise does not depend solely on lowered cerebral blood flow as indicated by middle cerebral blood velocity.