The impact of lower-limb function on upper-limb pull and push strength in elite handcycling athletes.

This study investigated the impact of performing a closed kinetic chain with the lower limbs on isometric upper-limb pull and push strength. Sixty-two elite handcyclists were assessed with the Manual Muscle Test and allocated to groups with partial to normal (LLF) or no lower-limb (no-LLF) function. Both groups performed upper-limb strength measurements under two kinetic-chain conditions. During the closed-chain condition, the lower limbs were attached to two footrests, providing horizontal and vertical support. During the open-chain condition, the footrests were removed and the limbs were supported vertically by a horizontal plate. Repeated-measures ANOVA were conducted to investigate main effects (open vs. closed chain, LLF vs. no-LLF) and their interaction. During pull, LLF performed better (p < 0.001, +11%) by pushing against the footrests. However, this increase in pulling strength during a closed-chain condition was not observed in the no-LLF. Therefore, findings suggest an advantage for the least impaired athletes by being able to perform lower-limb closed chains during pulling. Handcyclists with LLF can maximise pulling performance by adjusting the footrests. The classification system should consider the implications of these findings on the allocation of athletes with different levels of LLF and/or on the equipment regulation.

Comorbidities and medical complexities of mobility device users: a retrospective study.

OBJECTIVE: To determine the medical complexities and comorbidities of individuals who utilise wheeled mobility devices. As well as, to examine costly events including the number of urinary tract infections (UTIs), hospitalizations, urgent care(UC)/emergency department (ED) visits that are commonly seen in this population over a period of time one year prior to and one year post receiving their wheeled mobility equipment. DESIGN/SETTING: A retrospective data review of 857 individual medical charts at a Level 1 Trauma Hospital and Clinic System. PARTICIPANTS: 330 male and female (24-92 years old) mobility device users with a wide range of diagnoses, of which: 56 used manual wheelchairs (MWC),138 scooters (POV), 123 power wheelchairs without integrated standing (PWC), and 13 power wheelchairs with integrated standing (iS-PWC). RESULTS: Overall, 92% (n = 304) had at least three medical comorbidities and medical complexities. The most common comorbidity was pain (91%). A change was noted in a lower incidence of UTIs in those using an iS-PWC, respectively 23% with at least 1 UTI in the year prior to and 8% in the year after the mobility device evaluation. CONCLUSIONS: The large number of comorbidities and medical complexities amongst all mobility device users is concerning. The burden and the accompanying healthcare costs of this population is high. The potential that iS-PWC and other interventions could have on reducing these issues should be explored further.Implications of rehabilitationRegardless of a person's primary diagnosis or the wheeled mobility device they use, 100% have at least one and 92% have at least three comorbidities and medical complexities if they spend the majority of their day sittingThe high healthcare cost situations such as Emergency Department visits, Urgent Care visits, hospitalizations, and Urinary Tract Infections are present across those that use all mobility device types and the means to potentially reduce these incidences should be further exploredThe introduction of integrated standing within a power wheelchair, as a means to minimize the frequency of comorbidities and medical complications, should also be investigated further.

Association between upper-limb isometric strength and handcycling performance in elite athletes.

This study investigated the association among isometric upper-limb strength of handcyclists and sport-specific performance outcomes. At two international events, 62 athletes were tested on upper-limb strength, measured with an isometric-strength setup and with Manual Muscle Test (MMT). Horizontal force (Fz), effectiveness, rate of development, variability, and asymmetries were calculated for upper-limb pull and push. Performance measures were mean (POmean) and peak (POpeak) 20-s sprint power output and average time-trial velocity (TTvelocity). Regression models were conducted to investigate which pull and push strength variables associated strongest with performance measures. Additional regression analyses were conducted with an MMT sum score as predictor. Push and pull Fz showed the strongest associations with all outcomes. Combined push and pull Fz explained (p < .001) 80-81% of variance of POmean and POpeak. For TTvelocity, only push Fz was included in the model explaining 29% of the variance (p < .001). MMT models revealed weaker associations with sprint PO (R2 = .38-.40, p < .001) and TTvelocity (R2 = .18, p = 0.001). The findings confirmed the relevance of upper-limb strength on handcycling performance and the significance of ratio-scaled strength measures. Isometric strength outcomes are adequate sport-specific indicators of impairment in handcycling classification, but future research should corroborate this notion and its potential to discriminate between sports classes.

Bicycling and Tricycling Road Race Performance in International Para-Cycling Events Between 2011 and 2019.

ABSTRACT: This study described bicycling (C classes) and tricycling (T classes) performance in the International Cycling Federation road race events between 2011 and 2019. A total of 3243 race results from 33 events were analyzed. Race velocity was calculated for each result. Bicycling and tricycling data were separately modeled using a linear mixed-effects model. Bicycling velocity was statistically different between all adjacent men's classes (Cohen d = 0.14-0.73) and between the women's C1 and C2 (d = 1.15) and C3 and C4 (d = 0.48) classes. The absence of statistical differences between some women's bicycling classes may be due to a limited number of observations in these classifications. As expected, velocity was statistically different between men's (d = 1.64) and women's (d = 1.38) T1 and T2 classes. Road race performance was hierarchical within the disciplines of bicycling and tricycling, although not all adjacent women's bicycling classes were statistically different. The existence of a performance hierarchy does not necessarily validate the classification system. The integration of information regarding athlete impairment type and severity, with performance data, would provide greater insight into the validity of the classification system and should be prioritized as an area of future research.

A Role for Trunk Function in Elite Recumbent Handcycling Performance?

Handcycling classification considers trunk function, but there is limited scientific evidence of trunk involvement in recumbent performance. This study investigated the association between trunk function and recumbent handcycling performance of athletes without upper-limb impairments (H3-H4 sport classes). The study was divided into two parts. First, 528 time-trial results from 81 handcyclists with spinal cord injury (SCI) were obtained between 2014 and 2020. Average time-trial velocity was used as performance measure and SCI level as trunk function determinant. Multilevel regression analysis was performed to analyse differences in performance among SCI groups while correcting for lesion completeness, sex, and age. Second, in 26 handcyclists, standardised trunk flexion strength was measured with a handheld dynamometer. Peak and mean power-output from a sprint test and time-trial average velocity were used as performance measures. Spearman correlations were conducted to investigate the association between trunk strength and performance. Results showed that the different SCI groups did not exhibit significant differences in performance. Furthermore, trunk flexion strength and performance exhibited non-significant weak to moderate correlations (for time-trial speed: rs = 0.36; p = 0.07). Results of both analyses suggest that trunk flexion strength does not seem to significantly impact recumbent handcycling performance in athletes without upper-limb impairments.

The effects on self-efficacy, motivation and perceived barriers of an intervention targeting physical activity and sedentary behaviours in office workers: a cluster randomized control trial.

BACKGROUND: The importance of physical activity on health is clear, but changing behaviour is difficult. Successful interventions aiming to improve physical activity and reduce sedentary behaviour is therefore of importance. The aim of this study was to evaluate effects on motivation, self-efficacy and barriers to change behaviour from two different behavioural intervention focusing either on reducing sedentary behaviour or on increasing physical activity as compared to a waiting list control group. METHODS: The study was designed as a cluster randomized control trial (RCT) within two private companies. Self-efficacy, motivation and perceived barriers were together with demographic variables assessed before and after a 6-month intervention. Participant cluster teams were randomly allocated to either the physical activity intervention (iPA), the sedentary behaviour intervention (iSED), or control group. The intervention was multi componential and included motivational counselling based on Cognitive behaviour therapy and Motivational interviewing, group activities and management involvement. Group differences were determined using Bayesian multilevel modelling (parameter estimate; credible interval (CI)), analysing complete cases and those who adhered to the protocol by adhering to at least 3 out of 5 intervention sessions. RESULTS: After the intervention, the complete cases analysis showed that the iPA group had significantly higher autonomous motivation (0.33, CI: 0.05-0.61) and controlled motivation (0.27, CI: 0.04-0.51) for physical activity compared with the control group. The iSED group scored less autonomous and controlled motivation compared to the iPA group (0.38, CI: - 0.69- -0.087 respectively - 0.32, CI: - 0.57-0.07) but no significant differences compared with the control group. Among individuals that adhered to the protocol, the results showed higher scores on Exercise (3.03, CI: 0.28-6.02) and Sedentary self-efficacy (3.59, CI: 0.35-7.15) for individuals in the iPA group and on Sedentary self-efficacy (4.77, CI: 0.59-9.44) for the iSED group compared to the control group. CONCLUSION: These findings indicate that the interventions were successful in increasing self-efficacy in each intervention group and autonomous motivation for exercise in the iPA group, in particular when actively participating in the motivational counselling sessions.

The relation between sprint power and road time trial performance in elite para-cyclists.

OBJECTIVES: Whilst cycling performance has been studied extensively, very little is known about the performance of para-cyclists. This study assessed the relation between sprint power and road time trial performance in elite para-cyclists, and whether this relation differed based on impairment type and type of bike used. DESIGN: Cross-sectional. METHODS: During international para-cycling events, 168 athletes (88 bicycles, 17 tricycles, 56 recumbent handbikes and 7 kneeling handbikes) performed 20-s sport-specific sprint tests (mean power output (POmean) W), and their road time trial performance (average speed (km/h)) was taken from the official results. Multilevel regression models to assess the relation of sprint with time trial performance were composed for i. leg-cyclists: bicycle and tricycle and ii. arm-cyclists: recumbent- and kneeling handbike, adjusted for identified confounders. Furthermore, impairment type (categorized as i) muscle power/range of motion, ii) limb deficiency/leg length difference, and iii) coordination) and bike type were tested as effect modifiers. RESULTS: POmean ranged from 303 ±â€¯12 W for recumbent handcyclists to 482 ±â€¯156 W for bicyclists. POmean was significantly related to time trial performance, for both leg-cyclists (ß = 0.010, SE = 0.003, p < 0.01) and arm-cyclists (ß = 0.029; SE = 0.005, p < 0.01), and impairment type and bike type were not found to be effect modifiers. CONCLUSIONS: Sprint power was related to road time trial performance in all para-cyclists, with no differences found in this relation based on impairment type nor bike type. For those competing on a bicycle, tricycle, recumbent- or kneeling handbike, sprint tests might therefore be useful to predict or monitor time trial performance.

Effects of Two Randomized and Controlled Multi-Component Interventions Focusing On 24-Hour Movement Behavior among Office Workers: A Compositional Data Analysis.

Intervention studies aiming at changing movement behavior have usually not accounted for the compositional nature of time-use data. Compositional data analysis (CoDA) has been suggested as a useful strategy for analyzing such data. The aim of this study was to examine the effects of two multi-component interventions on 24-h movement behavior (using CoDA) and on cardiorespiratory fitness among office workers; one focusing on reducing sedentariness and the other on increasing physical activity. Office workers (n = 263) were cluster randomized into one of two 6-month intervention groups, or a control group. Time spent in sedentary behavior, light-intensity, moderate and vigorous physical activity, and time in bed were assessed using accelerometers and diaries, both for 24 h in total, and for work and leisure time separately. Cardiorespiratory fitness was estimated using a sub-maximal cycle ergometer test. Intervention effects were analyzed using linear mixed models. No intervention effects were found, either for 24-h behaviors in total, or for work and leisure time behaviors separately. Cardiorespiratory fitness did not change significantly. Despite a thorough analysis of 24-h behaviors using CoDA, no intervention effects were found, neither for behaviors in total, nor for work and leisure time behaviors separately. Cardiorespiratory fitness did not change significantly. Although the design of the multi-component interventions was based on theoretical frameworks, and included cognitive behavioral therapy counselling, which has been proven effective in other populations, issues related to implementation of and compliance with some intervention components may have led to the observed lack of intervention effect.

The Role of Executive Function in the Effectiveness of Multi-Component Interventions Targeting Physical Activity Behavior in Office Workers.

A knowledge gap remains in understanding how to improve the intervention effectiveness in office workers targeting physically active (PA) behavior. We aim to identify the modifying effect of executive function (EF) on the intervention effectiveness targeting PA-behaviors, and to verify whether the observed effect varies by Job Demand Control (JDC) categories. This workplace-based intervention study included 245 participants who were randomized into a control group and two intervention arms-promoting physical activity (iPA) group or reducing sedentary behavior (iSED) group. The interventions were conducted through counselling-based cognitive behavioral therapy and team activities over 6 months. PA-behaviors were measured by an accelerometer. EF was assessed by the Trail Making Test-B, Stroop, and n-back test. The JDC categories were measured by the demand control questionnaire. Higher EF level at baseline was significantly associated with the intervention effect on increased sleep time (ß-coefficient: 3.33, p = 0.003) and decreased sedentary time (-2.76, p = 0.049) in the iSED-group. Participants with active jobs (high job demands, high control) presented significantly increased light-intensity PA in the iSED-group in comparison to the control group. Among participants with a high level of EF and active jobs, relative to the control group, the iPA-group showed a substantial increase in light-intensity PA (1.58, p = 0.036) and the iSED-group showed a tendency of reducing sedentary behavior (-5.35, p = 0.054). The findings suggest that office workers with a high EF and active jobs may benefit most from an intervention study targeting PA-behaviors.

Para-cycling race performance in different sport classes.

PURPOSE: The para-cycling classification system, consisting of five classes (C1-C5) for bicycling (C5 athletes having least impairments), is mostly based on expert-opinion rather than scientific evidence. The aim of this study was to determine the differences in race performance between para-cycling classes. METHODS: From official results of the men's 1 km time trials for classes C1-C5 of seven Union Cycliste Internationale World Championships and Paralympics, median race speed of the five fastest athletes in each class was calculated (n = 175). Para-cycling results were expressed as a percentage of able-bodied performance using race results from the same years (n = 35). To assess differences between consecutive classes, Kruskal-Wallis tests with Mann-Whitney U post hoc tests were performed, correcting for multiple testing (p < 0.013). RESULTS: Para-cyclists in C1 reached 75% (median ± interquartile range = 44.8 ± 4.2 km/h) and in C5 90% (53.5 ± 2.9 km/h) of able-bodied race speed (59.4 ± 0.9 km/h). Median race speed between consecutive classes was significantly different (χ2 = 142.6, p < 0.01), except for C4 (52.1 ± 2.8 km/h) and C5 (U = 447.0, p = 0.05). CONCLUSION: Current para-cycling classification does not clearly differentiate between classes with least impairments. IMPLICATIONS FOR REHABILITATIONThe current classification system is not evidence-based and does not clearly differentiate between relevant groups of para-cyclists.An evidence-based para-cycling classification system is essential for a fair and equitable competition.Fair competition will make it more interesting and increase participation.Para-cycling can inspire everyone with and even those without disabilities to be physically active.

The effectiveness of multi-component interventions targeting physical activity or sedentary behaviour amongst office workers: a three-arm cluster randomised controlled trial.

BACKGROUND: Interventions to increase physical activity or reduce sedentary behaviour within the workplace setting have shown mixed effects. This cluster randomised controlled trial assessed whether multi-component interventions, focusing on changes at the individual, environmental, and organisational levels, either increased physical activity or reduced sedentary behaviour, compared to a passive control group. METHODS: Teams of office-workers from two companies participated in one of two interventions (iPA: targeting physical activity; or iSED: targeting sedentary behaviour), or wait-list control group (C). Exclusion criterion was very high physical activity level (MVPA ≥30 min/day in ≥10 min bouts every day). Randomisation occurred at the level of workplace cluster, and groups were randomly allocated (1:1) with stratification for company and cluster size. Personnel involved in data collection and processing were blinded to group allocation. Both interventions included five sessions of cognitive behavioural therapy counselling for 6 months. iPA included counselling focused on physical activity, access to a gym, and encouragement to exercise, and go for lunch walks. iSED included counselling on sedentary behaviour and encouragement to reduce sitting and increase engagement in standing- and walking-meetings. At baseline and the 6-month mark accelerometers were worn on the hip and thigh for 7 days. The primary outcomes were group differences in time spent in moderate-to-vigorous intensity physical activity (%MVPA) and in sedentary behaviour (%), analysed using Bayesian multilevel modelling for those with complete data. RESULTS: Two-hundred and sixty three office workers (73% women, mean age 42 ± 9 years, education 15 ± 2 years) were randomised into 23 cluster teams (iPA n = 84, 8 clusters; iSED n = 87, 7 clusters; C n = 92, 7 clusters). No significant group differences (posterior mean ratios: 95% credible interval) were found after the intervention for %MVPA or for %Sedentary. %MVPA: iPA vs C (0·04: - 0·80-0·82); iSED vs C (0·47: - 0·41-1·32); iPA vs iSED (0·43: - 0·42-1·27). %Sedentary: iPA vs C (1·16: - 1·66-4·02); iSED vs C (- 0·44: - 3·50-2·64); iPA vs iSED (- 1·60: - 4·72-1·47). CONCLUSIONS: The multi-component interventions focusing on either physical activity or sedentary behaviour were unsuccessful at increasing device-measured physical activity or reducing sedentary behaviour compared to a control group. TRIAL REGISTRATION: ISRCTN, ISRCTN92968402 . Registered 27/2/2018, recruitment started 15/03/2018.

Unfavourable sedentary and physical activity behaviour before and after retirement: a population-based cohort study.

BACKGROUND: During transition to retirement there is often a rearrangement of daily life which might provide a key opportunity for interventions to promote a non-sedentary and active lifestyle. To be able to design effective interventions, it is essential to know which sedentary and physical behaviour domains (eg, at home or during leisure time) have potential to facilitate healthy ageing during the retirement transition. OBJECTIVE: To determine whether unfavourable sedentary and physical activity behaviour before retirement predict unfavourable sedentary and physical activity behaviour after retirement. DESIGN: Population-based cohort. SETTING AND PARTICIPANTS: Adults (n=3272) employed in 2010 but retired in 2014. METHODS: Self-reported preretirement job activity, sedentary leisure time, physical activity at home, and walking-cycling and exercise were assessed as predictors for unfavourable sedentary and physical activity behaviours after retirement using logistic regression. Unfavourable behaviours were defined based on the respective median of the cohort distribution. Furthermore, the OR for having multiple unfavourable behaviours after retirement was determined, based on the amount of unfavourable behaviours before retirement. All models were adjusted for gender and education. RESULTS: Unfavourable preretirement physical activity and sedentary behaviour at home or during leisure time were the strongest predictors of the same behaviours after retirement. Unfavourable job activity did not predict physical activity but did predict unfavourable sedentary behaviour after retirement (OR=1.66, 95% CI 1.41 to 1.96). Unfavourable exercise behaviour before retirement predicted unfavourable sedentary and physical activity after retirement in all domains. With all behaviours being unfavourable before retirement, the OR of having at least three unfavourable behaviours after retirement was 36.7 (95% CI 16.8 to 80.5). CONCLUSIONS: Adults with a higher number of unfavourable preretirement physical activity and sedentary behaviours are likely to carry these unfavourable behaviours into retirement age. Interventions should target those with more unfavourable preretirement physical activity and sedentary behaviours before retirement, and those interventions focusing on exercise might have greatest potential.

Is moving to a greener or less green area followed by changes in physical activity?

Green areas might provide an inviting setting and thereby promote physical activity. The objective of this study was to determine whether moving to different green area surroundings was followed by changes of physical activity. Data from a large population-based cohort of adults in Stockholm County responding to surveys in 2010 and 2014 were analysed (n = 42611). Information about walking/cycling and exercise were self-reported and living area greenness data were satellite-derived (NDVI, Normalized Difference Vegetation Index). Multinomial logistic regression analyses were performed separately for changes in levels of walking/cycling and exercise (decrease, stable, increase). Greenness was defined as a change in NDVI quartile to less green, same, or greener. Odds ratio's (OR) with 95% confidence intervals (CI) were presented adjusted for gender, age, education and area-based income. Contrary to what we hypothesized, those moving to a greener area were more likely to decrease their levels of walking/cycling (OR = 1.42, CI = 1.28-1.58), whereas those moving to a less green area were more likely to increase their walking/cycling (OR = 1.26, CI = 1.13-1.41). Exercise behaviour showed another pattern, with people being more likely to decrease exercise both when moving to a greener (OR = 1.25, CI = 1.22-1.38) and to a less green area (OR = 1.22, CI = 1.09-1.36). Studying subpopulations based on sociodemographic characteristics did not aid to clarify our results. This cohort study with repeated measurements did not support the currently available cross-sectional studies showing a strong positive relation between greenness and physical activity. Nevertheless, our findings have shown spatial patterns related to green areas and physical activity which imply a need for place-specific health policies.

Improving office workers' mental health and cognition: a 3-arm cluster randomized controlled trial targeting physical activity and sedentary behavior in multi-component interventions.

BACKGROUND: Physically inactive and sedentary lifestyles are negatively related to both mental health and cognition. For office-workers, who spend two-thirds of their workday sitting, it is important to improve these lifestyles. The aim of this study is to assess the effectiveness of multi-component interventions, incorporating individual, environmental and organizational changes, to increase physical activity or reduce sedentary behavior among office-workers in order to improve mental health and cognition. METHODS: a 3-arm, clustered randomized controlled trial (RCT) with waiting list control group amongst adult office-workers of two large Swedish companies. Cluster teams will be randomized into 6-month interventions or to a passive waiting list control group which will receive the allocated intervention with a 6-month delay. Two multicomponent interventions will be studied of which one focuses on improving physical activity and the other on reducing sedentary behavior. Both interventions include 5 sessions of motivational counselling. In the physical activity intervention persons also get access to a gym and team leaders will organize lunch walks and encourage to exercise. In the sedentary behavior intervention standing- and walking meetings will be implemented and team leaders will encourage to reduce sitting. The recruitment target is 110 office-workers per arm (330 in total). Measurements will be repeated every 6 months for a total intended duration of 24 months. Proximal main outcomes are physical activity measured with accelerometers and sedentary behavior with inclinometers. Distal outcomes are self-reported mental health and a cognition test battery. Additional outcomes will include cardiovascular fitness, body composition, sleep, self-reported physical activity and sedentary behavior, other health habits, physical health, and working mechanisms from blood samples and questionnaires. DISCUSSION: This cluster RCT will contribute to the currently available evidence by comparing the effectiveness of multi-component interventions targeting physical activity or sedentary behavior with the end goal of improving mental health and cognition. This study is strong in its cluster randomized design, numerous objective outcome measures and long-term follow-up. The exact content of the interventions has been defined by combining theory with results from a larger research project as well as having a continuous dialogue with the involved companies. TRIAL REGISTRATION: ISRCTN92968402 .

Physical activity in wheelchair-using youth with spina bifida: an observational study.

BACKGROUND: Even though typically developing youth are already at risk for physical inactivity, youth with spina bifida may be even at higher risk as a consequence of their reduced mobility. No objective data is available for youth with spina bifida who use a manual wheelchair, so the seriousness of the problem is unknown. The purpose of this observational study was to quantify physical activity in wheelchair-using youth with spina bifida and evaluate the intensity of activities. METHODS: Fifty-three children and adolescents (5-19 years) with spina bifida who use a manual wheelchair for daily life, long distances or sports were included. To assess time spent in several types of activities VitaMove data of 34 participants were used and were presented as time spent sedentary and time spent physically active. This was compared to reference data of typically developing youth. To assess time spent in several intensities Actiheart data of 36 participants were used. The intensities were categorized according to the American College of Sports Medicine, ranging from very light intensity to near to maximal intensity. Data of 25 participants were used to combine type of activity and intensity. RESULTS: Children and adolescents with spina bifida who use a manual wheelchair were more sedentary (94.3% versus 78.0% per 24 h, p < 0.000) and less physically active (5.0% versus 12.2% per 24 h, p < 0.000) compared to typically developing peers. Physical activity during weekend days was worse compared to school days; 19% met the Guidelines of Physical Activity during school days and 8% during weekend days. The intensities per activity varied extensively between participants. CONCLUSIONS: Children and adolescents with spina bifida who use a manual wheelchair are less physically active and more sedentary than typically developing youth. The physical activity levels on school days seem to be more favorable than the physical activity levels on a weekend day. The low levels of physical activity need our attention in pediatric rehabilitation practice. The different intensities during activities indicate the importance of individually tailored assessments and interventions.

Effects of push-off ability and handcycle type on handcycling performance in able-bodied participants.

OBJECTIVE: To assess the effects on handcycling performance and physiological responses, of: (i) making a closed chain by comparing handcycling in a recumbent bike with 2-feet footrest (closed chain) with handcycling with 1 footrest (partial closed chain) and without a footrest (no closed chain); (ii) equipment by comparing handcycling in a recumbent bike with a kneeling bike. METHODS: Ten able-bodied participants performed submaximal exercise and sprint tests, once in a knee-ling bike and 3 times on a recumbent: 2-feet support, 1-foot support and without foot support. Physical strain (submaximal oxygen uptake and heart rate), peak (POpeak) and mean power output (POmean) were measured. RESULTS: Significantly higher POpeak and POmean were found with 2-feet support (mean 415 W (standard deviation (SD) 163) and mean 281 W (SD 96)) and higher POmean with 1-foot support (mean 279 W (SD 104)) compared with no foot support (mean 332 W (SD 127) and mean 254 W (SD 101)), p < 0.05. No differences were found for physical strain. In the kneeling bike, POpeak and POmean were significantly higher (mean 628 W (SD 231) and 391 W (SD 121)) than in the recumbent (mean 415 W (SD 163) and 281 W (SD 96)), p = 0.001. CONCLUSION: The ability to make a closed chain has a significant positive effect on handcycling sprint performance; therefore, this ability may be a discriminating factor. Sprint performance was significantly higher in kneeling compared with recumbent handcycling.

Common Perceived Barriers and Facilitators for Reducing Sedentary Behaviour among Office Workers.

Qualitative studies identified barriers and facilitators associated with work-related sedentary behaviour. The objective of this study was to determine common perceived barriers and facilitators among office workers, assess subgroup differences, and describe sedentary behaviour. From two Swedish companies, 547 office workers (41 years (IQR = 35–48), 65% women, 66% highly educated) completed questionnaires on perceived barriers and facilitators, for which subgroup differences in age, gender, education, and workplace sedentary behaviour were assessed. Sedentary behaviour was measured using inclinometers (n = 311). The most frequently reported barrier was sitting is a habit (67%), which was reported more among women than men (Χ² = 5.14, p = 0.03) and more among highly sedentary office workers (Χ² = 9.26, p < 0.01). The two other most reported barriers were that standing is uncomfortable (29%) and standing is tiring (24%). Facilitators with the most support were the introduction of either standing- or walking-meetings (respectively 33% and 29%) and more possibilities or reminders for breaks (31%). The proportion spent sedentary was 64% at the workplace, 61% on working days, and 57% on non-working days. This study provides a detailed understanding of office workers’ ideas about sitting and means to reduce sitting. We advise to include the supported facilitators and individualized support in interventions to work towards more effective strategies to reduce sedentary behaviour.

Are changes in occupational physical activity level compensated by changes in exercise behavior?

Background: Physically active occupations with high-energy expenditure may lead to lower motivation to exercise during leisure time, while the reverse can be hypothesized for sedentary occupations. The aim of this study was to investigate the impact of changing occupational activity level on exercise behavior. Methods: Data on occupational physical activity and leisure time exercise were taken from a population-based cohort, with surveys completed in 2010 and 2014. Using data on those employed in both years, two trajectories were analyzed: (i) participants who changed from sedentary to active occupations and (ii) participants who changed from active to sedentary occupations. Exercise was reported in hours per week and changes from 2010 to 2014 were categorized as decreased, increased or stable. Associations were expressed as ORs and 95% CIs adjusting for age, gender and education. Results: Data were available for 12 969 participants (57% women, aged 45 ± 9 years, 57% highly educated). Relative to participants whose occupational activity was stable, participants who changed to active occupations (n = 549) were more likely to decrease exercise (OR = 1.22, 95% CI = 1.02-1.47) and those who changed to sedentary occupations (n = 373) more likely to increase exercise levels (OR = 1.21, 95% CI = 0.97-1.52). Conclusion: People changing from sedentary to active occupations compensate by exercising less, and those changing from physically active to sedentary occupations seem to compensate by exercising more in their leisure time. When developing and evaluating interventions to reduce occupational sedentary behavior or to promote exercise, mutual influences on physical activity of different contexts should be considered.

Do unfavourable alcohol, smoking, nutrition and physical activity predict sustained leisure time sedentary behaviour? A population-based cohort study.

Comparing lifestyle of people remaining sedentary during longer periods of their life with those favourably changing their behaviour can provide cues to optimize interventions targeting sedentary behaviour. The objective of this study was to determine lifestyle predictors of sustained leisure time sedentary behaviour and assess whether these predictors were dependent on gender, age, socioeconomic position and occupational sedentary behaviour. Data from a large longitudinal population-based cohort of adults (aged 18-97years) in Stockholm responding to public health surveys in 2010 and 2014 were analysed (n=49,133). Leisure time sedentary behaviour was defined as >3h per day of leisure sitting time e.g. watching TV, reading or using tablet. Individuals classified as sedentary at baseline (n=9562) were subsequently categorized as remaining sedentary (n=6357) or reduced sedentary behaviour (n=3205) at follow-up. Lifestyle predictors were unfavourable alcohol consumption, smoking, nutrition, and physical activity. Odds ratios (OR) and corresponding 95% Confidence Intervals (CI) were calculated, adjusting for potential confounders. Unfavourable alcohol consumption (OR=1.22, CI:1.11-1.34), unfavourable candy- or cake consumption (OR=1.15, CI:1.05-1.25), and unfavourable physical activity in different contexts were found to predict sustained sedentary behaviour, with negligible differences according to gender, age, socioeconomic position and occupational sedentary behaviour. People with unfavourable lifestyle profiles regarding alcohol, sweets, or physical activity are more likely to remain sedentary compared to sedentary persons with healthier lifestyle. The impact of combining interventions to reduce leisure time sedentary behaviour with reducing alcohol drinking, sweet consumption and increasing physical activity should be tested as a promising strategy for behavioural modification.

Working mechanisms of a behavioural intervention promoting physical activity in persons with subacute spinal cord injury.

OBJECTIVE: In order to unravel the working mechanisms that underlie the effectiveness of a behavioural intervention promoting physical activity in persons with subacute spinal cord injury, the aim of this study was to assess the mediating effects of physical and psychosocial factors on the intervention effect on physical activity. DESIGN: Randomized controlled trial. SETTING: Four rehabilitation centres in the Netherlands. SUBJECTS: Thirty-nine persons with subacute spinal cord injury. INTERVENTION: Behavioural intervention promoting an active lifestyle, based on motivational interviewing. The intervention involved a total of 13 individual sessions beginning 2 months before and ending 6 months after discharge from initial inpatient rehabilitation. MAIN MEASURES: The potential mediating effects of fatigue, pain, depression, illness cognition, exercise self-efficacy, coping and social support on the effect of the behavioural intervention on objectively measured physical activity (B = 0.35 h, p < 0.01) were studied. Measurements were performed at baseline, discharge, 6 months and 1 year after discharge. RESULTS: No single factor was found that strongly mediated the effect of the behavioural intervention on physical activity; however, multiple factors could partly explain the effect. Mediating effects greater than 10% were found for proactive coping (17.6%), exercise self-efficacy (15.9%), pain disability (15.3%) and helplessness (12.5%). DISCUSSION: Proactive coping (the ability to anticipate and deal with potential threats before they occur), exercise self-efficacy (self-confidence with respect to performing exercise and daily physical activities), pain disability (interference by pain of daily activities) and helplessness (emphasizing the aversive meaning of the disease) are important concepts in interventions promoting physical activity in persons with subacute spinal cord injury.