A Home-Based Program of Transcutaneous Electrical Nerve Stimulation and Task-Related Trunk Training Improves Trunk Control in Patients With Stroke The Additive Effects of Core Muscle Strengthening and Trunk NMES on Trunk Balance in Stroke Patients The Effects of Core Stabilization Exercise on Dynamic Balance and Gait Function in Stroke Patients Which is better in the rehabilitation of stroke patients, core stability exercises or conventional exercises? Efficacy of Trunk Regimes on Balance, Mobility, Physical Function, and Community Reintegration in Chronic Stroke: A Parallel-Group Randomized Trial. Effect of Core Stability Training on Trunk Function, Standing Balance, and Mobility in Stroke Patients Effects of Weight-shifting Exercise Combined with Transcutaneous Electrical Nerve Stimulation on Muscle Activity and Trunk Control in Patients with Stroke. Weight-shift training improves trunk control, proprioception, and balance in patients with chronic hemiparetic stroke. Additional Exercises Improve Trunk Performance After Stroke: A Pilot Randomized Controlled Trial Task-related training improves performance of seated reaching tasks after stroke. A randomized controlled trial. Training symmetry of weight distribution after stroke: a randomized controlled pilot study comparing task-related reach, Bo bath and feedback training approaches Time Course of Trunk, Arm, Leg, and Functional Recovery After Ischemic Stroke Reliability of the PEDro scale for rating quality of randomized controlled trials. Effects of scapulohumeral rehabilitation protocol on trunk control recovery in patients with subacute stroke: A pilot randomized controlled trial. The effect of additional core stability exercises on improving dynamic sitting balance and trunk control for subacute stroke patients: a randomized controlled trial Sitting training early after stroke improves sitting ability and quality and carries over to standing up but not to walking: a randomised trial. Randomized Controlled Trial of Truncal Exercises Early After Stroke to Improve Balance and Mobility
Background . Impaired trunk motor control is common after stroke . Combining transcutaneous electrical nerve stimulation ( TENS ) with task-related trunk training ( TRTT ) has been shown to enhance the recovery of lower limb motor function . Objective . This study investigated whether combining TENS with TRTT would enhance trunk control after stroke . Methods . Thirty-seven subjects with stroke were recruited into a r and omized controlled clinical trial . Subjects were r and omly assigned to any one of the three 6-week home-based training groups : ( 1 ) TENS + TRTT , ( 2 ) placebo TENS + TRTT , or ( 3 ) control without active training . The outcome measures included isometric peak trunk flexion torque and extension torque ; forward seated and lateral seated reaching distance to the affected and unaffected side ; and Trunk Impairment Scale ( TIS ) scores . All outcome measures were assessed at baseline , after 3 and 6 weeks of training , and 4 weeks after training ended at follow-up . Results . Both the TENS + TRTT and the placebo-TENS + TRTT groups had significantly greater improvements in isometric peak trunk flexion torque and extension torque , lateral seated reaching distance to affected and unaffected side , and TIS score than the control group after 3 weeks of training . The TENS + TRTT group had significantly greater and earlier improvement in its mean TIS score than the other 2 groups . Conclusions . Home-based TRTT is effective for improving trunk muscle strength , sitting functional reach and trunk motor control after stroke in subjects without somatosensory deficits . The addition of TENS to the trunk augments the effectiveness of the exercise in terms of TIS scores within the first 3 weeks of training Objective To investigate an additive effect of core muscle strengthening ( CMS ) and trunk neuromuscular electrical stimulation ( tNEMS ) on trunk balance in stroke patients . Methods Thirty patients with acute or subacute stroke who were unable to maintain static sitting balance for > 5 minutes were enrolled and r and omly assigned to 3 groups , i.e. , patients in the CMS ( n=10 ) group received additional CMS program ; the tNMES group ( n=10 ) received additional tNMES over the posterior back muscles ; and the combination ( CMS and tNMES ) group ( n=10 ) received both treatments . Each additional treatment was performed 3 times per week for 20 minutes per day over 3 weeks . Korean version of Berg Balance Scale ( K-BBS ) , total score of postural assessment scale for stroke patients ( PASS ) , Trunk Impairment Scale ( TIS ) , and Korean version of Modified Barthel Index ( K-MBI ) were evaluated before and after 3 weeks of therapeutic intervention . Results All 3 groups showed improvements in K-BBS , PASS , TIS , and K-MBI after therapeutic interventions , with some differences . The combination group showed more improvements in K-BBS and the dynamic sitting balance of TIS , as compared to the CMS group ; and more improvement in K-BBS , as compared to the tNMES group . Conclusion The results indicated an additive effect of CMS and tNMES on the recovery of trunk balance in patients with acute or subacute stroke who have poor sitting balance . Simultaneous application of CMS and tNMES should be considered when design ing a rehabilitation program to improve trunk balance in stroke patients [ Purpose ] The purpose of this study was to determine the effects of core stabilization exercise on dynamic balance and gait function in stroke patients . [ Subjects ] The subjects were 16 stroke patients , who were r and omly divided into two groups : a core stabilization exercise group  of eight subjects and  control group of eight subjects . [ Methods ] Subjects in both groups received general training five times per week . Subjects in the core stabilization exercise group practice d an additional core stabilization exercise program , which was performed for 30 minutes , three times per week , during a period of four weeks . All subjects were evaluated for dynamic balance ( Timed Up and Go test , TUG ) and gait parameters ( velocity , cadence , step length , and stride length ) . [ Results ] Following intervention , the core exercise group showed a significant change in TUG , velocity , and cadence . The only significant difference observed between the core group and control group was in velocity . [ Conclusion ] The results of this study suggest the feasibility and suitability of core stabilization exercise for stroke patients [ Purpose ] The aim of this study was to determine which is better in the rehabilitation of stroke patients , core stability exercises or conventional exercises . [ Subjects and Methods ] Forty participants with hemiplegia were recruited in the Department of Neurology of Yidu Central Hospital of Weifang between January 2014 and February 2015 and r and omly divided into either an experimental or control group . The patients in the control group performed conventional exercises for six weeks , and those in the experiment group performed core stability exercises for six weeks . The outcomes were evaluated using Modified Barthel Index and Berg Balance Scale . [ Results ] After treatment , the Modified Barthel Index and Berg Balance Scale were significantly increased in both groups when compared with the baseline . The Modified Barthel Index was significantly lower in the control group compared with the experimental group . The Berg Balance Scale scores in the control group were relatively lower than those in the experimental group , but there was no significant difference between the two groups . [ Conclusion ] Core stability exercises have a better effect on patients with hemiplegia than conventional exercises OBJECTIVE The study objective was to examine the efficacy of plinth and Swiss ball-based trunk exercise regimes on balance , mobility , physical function , and community reintegration compared with st and ard physiotherapy in chronic stroke . SUBJECTS AND METHODS This observer-blinded parallel-group r and omized trial was conducted in outpatient stroke units . People with chronic stroke aged between 30 and 75 years , first onset of unilateral cortical lesion , poor trunk performance , 10 m independent walking ability with or without walking aids , and absence of pusher syndrome were included .  Trunk Impairment Scale 2.0 , Brunel Balance Assessment , Tinetti scale , gait speed , Stroke Impact Scale-16 , and Reintegration to Normal Living Index were the measures . Experimental interventions involved the practice of selective upper and lower trunk movements using either plinth or Swiss ball . Control group received st and ard physiotherapy . All the patients practice d 1 hour exercise session , 3 sessions a week over a duration of 6 weeks and followed up after 3 and 12 months . RESULTS Of 108 patients allocated into 3 groups , baseline characteristics were similar . Postintervention compared with control group , the plinth , and Swiss ball groups showed significant mean changes in the outcome measures : trunk impairment scale 2.0 ( 3.6;4.1 points ) , Brunel Balance Assessment ( 1-level ) , Tinetti scale ( 5;5.2 points ) , gait speed ( .06;.08 m/s ) , Stroke Impact Scale-16 ( 8.7;7.2 points ) , and community reintegration ( 7.6;8.8 points ) . These improvements were retained during 3 - 12 months ' follow-up . Statistical significant was set at P < .05 . CONCLUSION Plinth and Swiss ball-based trunk exercise regimes showed significant improvements in balance , mobility , physical function , and community reintegration in chronic stroke as against st and ard physiotherapy Background . Trunk function is important for st and ing balance , mobility , and functional outcome after stroke , but few studies have evaluated the effects of exercises aim ed at improving core stability in stroke patients . Objective . To investigate the effectiveness of core stability training on trunk function , st and ing balance , and mobility in stroke patients . Methods . An assessor-blinded , r and omized controlled trial was undertaken in a stroke rehabilitation ward , with 32 participants r and omly assigned to an experimental group or a control group ( n = 16 each ) . The experimental group received 400 minutes of core stability training in place of conventional programs within total training time , while the control group received only conventional programs . Primary outcome measures were evaluated using the Trunk Impairment Scale ( TIS ) , which reflects trunk function . Secondary outcome measures were evaluated by pelvic tilt active range of motion in the sagittal plane , the Balance Evaluation Systems Test – brief version ( Brief-BESTest ) , Functional Reach test , Timed Up- and -Go test ( TUG ) , and Functional Ambulation Categories ( FAC ) . A general linear repeated- measures model was used to analyze the results . Results . A treatment effect was found for the experimental group on the dynamic balance subscale and total score of the TIS ( P = .002 and P < .001 , respectively ) , pelvic tilt active range of motion ( P < .001 ) , Brief-BESTest ( P < .001 ) , TUG ( P = .008 ) , and FAC ( P = .022 ) . Conclusions . Core stability training has beneficial effects on trunk function , st and ing balance , and mobility in stroke patients . Our findings might provide support for introducing core stability training in stroke rehabilitation This study investigated the effects of weight-shifting exercise ( WSE ) combined with transcutaneous electrical nerve stimulation ( TENS ) , applied to the erector spinae and external oblique ( EO ) muscles , on muscle activity and trunk control in patients with hemiparetic stroke . Sixty patients with stroke were recruited to this study and r and omly distributed into three treatment groups : ( 1 ) WSE + TENS , ( 2 ) WSE + placebo TENS , and ( 3 ) control . All participants underwent 30 sessions of training ( 30 minutes five times per week for 6 weeks ) and received 1 hour of conventional physical therapy five times per week for 6 weeks . Muscle activity , maximum reaching distance and trunk impairment scale scores were assessed in all patients before and after the training . After training , the WSE + TENS group showed significant increase in the EO activity , maximum reaching distance and trunk impairment scale scores compared with the WSE + placebo TENS and control groups . These findings suggest that WSE with TENS applied to the erector spinae and EO muscles increased the trunk muscle activity and improved trunk control . Therefore , WSE with TENS could be a beneficial intervention in clinical setting s for individuals with hemiparetic stroke . Copyright © 2016 John Wiley & Sons , Trunk instability is one of main problems in survivors following stroke . We investigated the effects of weight-shift training ( WST ) on an unstable surface in sitting position on trunk control , proprioception , and balance in individuals with chronic hemiparetic stroke . Eighteen participants with chronic hemiparetic stroke were recruited and were allocated to either WST or control group . The WST group received a weight-shift training program for 30 min and then received a conventional exercise program for 30 min , while the control group received conventional exercise program for 60 min , five times a week for four weeks for both groups . In this r and omized control study , we used three outcome measures : trunk reposition error ( TRE ) , Trunk Impairment Scale ( TIS ) , and Timed Up and Go ( TUG ) test . TRE was measured by each participant 's reposition error to the target angle during his/her active trunk movement . TIS and TUG were examined for trunk control abilities and dynamic balance abilities , respectively . After training , TRE showed significantly greater improvement in the WST group ( mean change , 1.67 ± 1.45˚ ) than the control group ( mean change , 0.08 ± 1.05˚ ) . The TIS score was significantly higher in the WST group ( mean change , 2.33 ± 1.50 ) than the control group ( mean change , 0.13 ± 0.83 ) . The TUG test also showed a significant improvement in the WST group ( mean change , 5.03 ± 1.88 sec ) than the control group ( mean change , 2.59 ± 1.86 sec ) . Our findings indicate that weight-shift training is beneficial for improving trunk control and proprioception in patients with chronic hemiparetic stroke Background . Sitting balance and the ability to perform selective trunk movements are important predictors of functional outcome after stroke . However , studies evaluating the effect of exercises aim ed at improving trunk performance are sparse . Objective . To examine the effect of additional trunk exercises on trunk performance after stroke . Methods . An assessor-blinded r and omized controlled trial was carried out at an inpatient stroke rehabilitation center . In total 33 participants were assigned to an experimental group ( n = 17 ) or a control group ( n = 16 ) . In addition to conventional therapy , the experimental group received 10 hours of individual and supervised trunk exercises ; 30 minutes , 4 times a week , for 5 weeks . Trunk performance was evaluated by the Trunk Impairment Scale ( TIS ) and its subscales of static and dynamic sitting balance and coordination . A general linear repeated measures model was used to analyze the results of our study . Results . No significant differences were found pretreatment between the 2 groups for the collected demographic variables , stroke-related parameters , clinical measures , number of therapy sessions received , and primary outcome measure used . Posttreatment , a significantly better improvement was noted in the experimental group compared to the control group for the dynamic sitting balance subscale only ; measuring selective lateral flexion initiated from the upper and lower part of the trunk , ( P = .002 , post hoc power calculation = .90 , effect size = 1.16 ) . Conclusions . Our results suggest that , in addition to conventional therapy , trunk exercises aim ed at improving sitting balance and selective trunk movements have a beneficial effect on the selective performance of lateral flexion of the trunk after stroke BACKGROUND AND PURPOSE After stroke , the ability to balance in sitting is critical to independence . Although impairments in sitting balance are common , little is known about the effectiveness of rehabilitation strategies design ed to improve it . The purpose of this r and omized placebo-controlled study was to evaluate the effect of a 2-week task-related training program aim ed at increasing distance reached and the contribution of the affected lower leg to support and balance . METHODS Twenty subjects at least 1 year after stroke were r and omized into an experimental or control group . The experimental group participated in a st and ardized training program involving practice of reaching beyond arm 's length . The control group received sham training involving completion of cognitive-manipulative tasks within arm 's length .  Performance of reaching in sitting was measured before and after training using electromyography , videotaping , and two force plates . Variables tested were movement time , distance reached , vertical ground reaction forces through the feet , and muscle activity . Subjects were also tested on sit-to-st and , walking , and cognitive tasks .  Nineteen subjects completed the study . RESULTS After training , experimental subjects were able to reach faster and further , increase load through the affected foot , and increase activation of affected leg muscles compared with the control group ( P < .01 ) . The experimental group also improved in sit-to-st and . The control group did not improve in reaching or sit-to-st and . Neither group improved in walking . CONCLUSIONS This study provides strong evidence of the efficacy of task-related motor training in improving the ability to balance during seated reaching activities after stroke Objective : To determine ( 1 ) the most effective of three treatment approaches to retrain seated weight distribution long-term after stroke and ( 2 ) whether improvements could be generalized to weight distribution in st and ing . Setting : Inpatient rehabilitation unit . Design : Forty asymmetrical acute stroke subjects were r and omly allocated to one of four groups in this pilot study . Changes in weight distribution were compared between the 10 subjects of each of three treatment groups ( task-specific reach , Bobath , or Balance Performance Monitor [ BPM ] feedback training ) and a no specific treatment control group . One week of measurement only was followed by two weeks of daily training sessions with the treatment to which the subject was r and omly allocated . Measurements were performed using the BPM daily before treatment sessions , two weeks after cessation of treatment and 12 weeks post study . Weight distribution was calculated in terms of mean balance ( percentage of total body weight ) or the mean of 300 balance points over a 30-s data run . Results : In the short term , the Bobath approach was the most effective treatment for retraining sitting symmetry after stroke ( p = 0.004 ) . Training with the BPM and no training were also significant ( p = 0.038 and p = 0.035 respectively ) and task-specific reach training failed to reach significance ( p = 0.26 ) . At 12 weeks post study 83 % of the BPM training group , 38 % of the task-specific reach group , 29 % of the Bobath group and 0 % of the untrained group were found to be distributing their weight to both sides . Some generalization of symmetry training in sitting to st and ing was noted in the BPM training group which appeared to persist long term . Conclusions : Results should be treated with caution due to the small group sizes . However , these preliminary endings suggest that it might be possible to restore postural symmetry in sitting in the early stages of rehabilitation with therapy that focuses on creating an awareness of body position Background . Patterns of recovery provide useful information concerning the potential of physical recovery over time and therefore the setting of realistic goals for rehabilitation programs . Objective . To compare the time course of trunk recovery with the patterns of recovery of arm , leg , and functional ability . Methods . Consecutive stroke patients were recruited in 2 acute neurology wards . Participants were evaluated at 1 week , 1 month , and 3 and 6 months after stroke . Patients were assessed with the Trunk Impairment Scale , Fugl-Meyer arm and leg test , and Barthel Index . Results . Thirty-two patients were included in the study . There were no dropouts . Repeated measures analysis of the recovery patterns of motor and functional performance revealed the most striking improvement for all measures from 1 week to 1 month ( P value between .0021 and < .0001 ) and a significant improvement from 1 month to 3 months after stroke ( P value ranges from .0008 to < .0001 ) . No significant improvement was found between 3 and 6 months after stroke for any of the measures . Statistical analysis revealed no significant difference between time course of trunk , arm , leg , and functional recovery ( P = .2565 ) . No significant differences in level of motor and functional recovery were found at the different time points . Conclusions . Separate analyses of motor and functional recovery patterns after stroke confirm the importance of the first month for recovery . Contrary to common belief , the time course of recovery of the trunk is similar to the recovery of arm , leg , and functional ability BACKGROUND AND PURPOSE Assessment of the quality of r and omized controlled trials ( RCTs ) is common practice in systematic review s. However , the reliability of data obtained with most quality assessment scales has not been established . This report describes 2 studies design ed to investigate the reliability of data obtained with the Physiotherapy Evidence Data base ( PEDro ) scale developed to rate the quality of RCTs evaluating physical therapist interventions . METHOD In the first study , 11 raters independently rated 25 RCTs r and omly selected from the PEDro data base . In the second study , 2 raters rated 120 RCTs r and omly selected from the PEDro data base , and disagreements were resolved by a third rater ; this generated a set of individual rater and consensus ratings . The process was repeated by independent raters to create a second set of individual and consensus ratings . Reliability of ratings of PEDro scale items was calculated using multirater kappas , and reliability of the total ( summed ) score was calculated using intraclass correlation coefficients ( ICC [ 1,1 ] ) . RESULTS The kappa value for each of the 11 items ranged from.36 to.80 for individual assessors and from.50 to.79 for consensus ratings generated by groups of 2 or 3 raters . The ICC for the total score was.56 ( 95 % confidence interval=.47-.65 ) for ratings by individuals , and the ICC for consensus ratings was.68 ( 95 % confidence interval=.57-.76 ) . DISCUSSION AND CONCLUSION The reliability of ratings of PEDro scale items varied from " fair " to " substantial , " and the reliability of the total PEDro score was " fair " to " good . BACKGROUND Despite upper limb rehabilitation is widely investigated in patients with stroke , the effects of scapulohumeral rehabilitation on trunk stabillization are mainly unknown . OBJECTIVE To test the effects of scapulohumeral rehabilitation protocol on trunk control recovery in patients with subacute stroke . METHODS A pilot r and omized controlled trial with two groups of 14 patients each one performing 20 minutes per day , 5 days a week , for 6 weeks in add on to st and ard therapy . Experimental group performed a specific scapulohumeral rehabilitation protocol aim ing to improve trunk competencies whereas control group performed conventional arm rehabilitation .  Clinical scale tests and accelerometric evaluations were performed pre- and post-treatment . RESULTS Experimental groups showed better scores at discharge at Trunk impairment Scale ( p < 0.001 ) , Barthel Index ( p = 0.024 ) , Trunk Control Test ( p = 0.002 ) , Sitting Balance Scale ( p = 0.002 ) , but neither at Fugl-Meyer Scale ( p = 0.194 ) nor Modified Ashworth Scale ( p = 0.114 ) . Accelerometric analysis showed higher stability of trunk for experimental group especially during static and dynamic items . CONCLUSIONS The recovery of scapulohumeral functions also acts on trunk stabilization post-stroke Objective : To examine the effect of core stability exercises on trunk control , dynamic sitting and st and ing balance , gait , and activities of daily living in subacute stroke patients . Design : A r and omized controlled trial . Setting : Inpatient rehabilitation hospital in two centres . Subjects : Eighty patients ( mean of 23.25 ( ±16.7 ) days post-stroke ) were r and omly assigned to an experimental group and a control group . Interventions : Both groups underwent conventional therapy for five days/week for five weeks and the experimental group performed core stability exercises for 15 min/day . The patients were assessed before and after intervention . Main measures : The Trunk Impairment Scale ( Spanish-Version ) and Function in Sitting Test were used to measure the primary outcome of dynamic sitting balance . Secondary outcome measures were st and ing balance and gait as evaluated via Berg Balance Scale , Tinetti Test , Brunel Balance Assessment , Postural Assessment Scale for Stroke ( Spanish-Version ) , and activities of daily living using Barthel Index . Results : The experimental group showed statistically significant differences for all of the total scale scores ( P<0.05 ) , except for the sitting section of the Brunel Balance Assessment . The mean ( SD ) difference between groups in Trunk Impairment Scale total score was 3.40 ( ±4.12 ) points , and its subscale dynamic sitting balance was 2.28 ( ±3.29 ) . The Berg Balance Scale was 14.54 ( ±18.19 ) points , and the Barthel Index was 13.17 ( ±25.27 ) points . Collectively , these results were in favour of the experimental group . Conclusions : Core stability exercises in addition to conventional  therapy improves trunk control , dynamic sitting balance , st and ing balance , gait and activities of daily living in subacute post-stroke patients QUESTION What is the effect of a sitting training protocol in people early after stroke on sitting ability and quality , and does it carry over to mobility ? DESIGN R and omised placebo-controlled trial with concealed allocation , assessor blinding and intention-to-treat analysis . PARTICIPANTS Twelve individuals who had a stroke less than three months previously and were able to sit unsupported . INTERVENTION The experimental group completed a 2-week sitting training protocol that involved practising reaching tasks beyond arm 's length . The control group completed a 2-week sham sitting training protocol that involved practising cognitive-manipulative tasks within arm 's length . OUTCOME MEASURES The primary outcome was sitting ability ( maximum reach distance ) . Secondary outcomes were sitting quality ( reach movement time and peak vertical force through affected foot during reaching ) and carry over to mobility ( peak vertical force through affected foot during st and ing up and walking speed during 10 m Walk Test ) . Outcome measures were taken before and after training and six months later . RESULTS After 2 weeks ' training , the experimental group had increased their maximum reach distance by 0.17 m ( 95 % CI 0.12 to 0.21 ) , decreased their movement time by 0.5 s ( 95 % CI -0.8 to -0.2 ) , increased their peak vertical force through the affected foot during reaching by 13 % of body weight ( 95 % CI 6 to 20 ) and increased their peak vertical force through the affected foot during st and ing up by 21 % of body weight ( 95 % CI 14 to 28 ) compared with the control group . After 6 months , significant between-group differences were maintained for maximum reach distance and peak vertical force through the affected foot during st and ing up . CONCLUSIONS The sitting training protocol was both feasible and effective in improving sitting and st and ing up early after stroke and somewhat effective six months later Background . Sitting balance and the ability to perform selective truncal movements are important predictors of functional outcome after stroke . However , few clinical trials have evaluated the effect of truncal exercises . Objective . The authors assessed the effect of additional truncal exercises on truncal function , st and ing balance , and mobility . Methods . An assessor-blinded r and omized controlled trial was carried out at a stroke rehabilitation hospital . A total of 33 participants ( mean 35 days post onset ) were r and omly assigned to an experimental group ( n = 18 ) or a  control group ( n = 15 ) . In addition to conventional therapy , the experimental group received 16 hours of truncal exercises . The control group received 16 hours of sham treatment .  Truncal function was evaluated by the Trunk Impairment Scale ( TIS ) and st and ing balance and mobility by the Tinetti Test . The Romberg with eyes open and eyes closed , Four Test Balance Scale ( FTBS ) , Berg Balance Scale ( BBS ) , Rivermead Motor Assessment Battery ( RMAB ) , Functional Ambulation Categories , and Dynamic Gait Index ( DGI ) were performed to eluci date the findings of the primary outcome measures . Results . A treatment effect was found for the experimental group on the TIS ( P < .001 ) , Tinetti Test ( P < .001 ) , FTBS ( P = .014 ) , BBS ( P = .007 ) , RMAB ( P < .001 ) , and DGI ( P = .006 ) . Conclusions . In addition to conventional therapy , truncal exercises have a beneficial effect on truncal function , st and ing balance , and mobility in people after stroke
Objective : To investigate the effectiveness of trunk training on trunk control , sitting and st and ing balance and mobility .