Physical Conditioning and Wheelchair Propulsion

Physical capacity is important to the development of wheelchair propulsion performance. Five articles have explored the relationship between physical conditioning and capacity, and wheelchair propulsion.

Author Year

Country
Research Design

Score
Total Sample Size

Methods Outcome
Gauthier et al. 2018

Canada

RCT

PEDro=5

Ninitial=11

Ninitial=9

Population: HIIT Group (n=4): Mean age= 33.9 yr; Gender: males=3, females=1; Level of injury range: C7-T10; Mean time since injury: 6.0 yr. MICT Group (n=5): Mean age= 43.2 yr; Gender: males=3, females=1; Level of injury range: C6-T11; Mean time since injury: 15.5 yr.

Intervention:  Participants were randomized to a home-based self-managed manual wheelchair program. The high-intensity interval training (HIIT) group alternated 30s high-intensity intervals and 60s low-intensity intervals. The moderate-intensity continuous training (MICT) maintained a constant moderate intensity. The programs were six wks, consisting of three 40-min propulsion training session/wk.

Outcome Measures: Cardiorespiratory Fitness: VO2, Heart Rate (HR), POpeak, RPEmuscu, RPEcardio; Upper Limb Strength: Shoulder (flexors, extensors, abductors, adductors, internal rotators, external rotators), Elbow (flexors, extensors).

1.     Cardiorespiratory fitness outcomes improved, but not significantly between groups from pre- to post- intervention (p>0.05).

2.     Similarly, upper limb strength did not significantly improve between groups for all outcome measures (p>0.05).

3.     The results suggest that the HIIT program appears feasible and safe and has comparable effects on most cardiorespiratory fitness and upper limb muscle strength values versus the MICT program.

van der Scheer et al. 2016

USA

RCT

PEDro=7

N=29

Population:  Exercise Group (n=14): Median age= 55 yr; Gender: males=12, females=2; Level of injury range: C4-L5; Median time since injury: 16.0 yr. Control Group (n=15): Median age= 57 yr; Gender: males=10, females=5; Level of injury range:  C4-L5; Median time since injury: 20.0 yr.

Intervention: Inactive manual wheelchairs (MWC) users were randomized to exercise group, or no exercise. The low-intensity training program was 16wks, consisting of wheelchair treadmill propulsion 2x/wk for 30min.

Outcome Measures:  Peak aerobic work capacity: VO2peak, POpeak; Submaximal fitness: MEsub1, MEsub2; Anaerobic work capacity:  5s peak power output over a 15-m overground sprint (P5-15m); Isometric Strength; Wheelchair Skills Performance (WSP): performance time, ability score, strain score; Physical activity levels: Physical Activity Scale for Individuals with Physical Disabilities (PASIPD), distance.

1.     Participants were, on average, able to increase power output and velocity over the training period.

2.     10/14 participants felt that the training improved their fitness.

3.     Most participants reported that wheelchair skill performance and physical activity levels had not changed.

4.     No significant training effects were found in peak aerobic work capacity, WSP or Physical activity levels.

5.     P5-15m was the only outcome measure that was statically significant between the control and intervention group (p=0.02).

Torhaug et al. 2016

Norway

Prospective Controlled Trial

Ninitial=18

Nfinal=16

Population:  MST (n=9): Median age= 42.0 yr; Gender: N/S; Level of injury range: T4-L1; Median time since injury: 14.6 yr. CG (n=7): Median age= 47.1 yr; Gender: N/S; Level of injury range:  T4-T12; Median time since injury: 15.4 yr.

Intervention: In order to evaluate wheelchair propulsion work economy (WE), participants either received maximal bench press strength training (MST), or to the control group (CG). MST group performed training 3x/wk, for 6wks, with 4 sets of four bench press repetitions.  CG performed no formalized exercise routine.

Outcome Measures:  WE: Oxygen uptake (VO2), Pulmonary ventilation (VE), Respiratory exchange ratio (RER).

 

1.     MST significantly improved WE compared to CG by 17.3%

2.     Mean reduction in VO2 was significantly improved in MST group compared to CG (p=0.007).

3.     VE and RER did not significantly differ between groups (p=0.96, p=0.9, respectively.

Kilkens et al. 2005

Netherlands

Cohort

N=97

Population: Mean age: 38yr; Gender: males=74, females=24; Level of injury: paraplegia=73, tetraplegia=25.

Intervention: Wheelchair Circuit test-eight standardized tasks in a fixed sequence on treadmill, hard and soft surface.

Outcome Measures: Upper extremity strength through manual muscle testing (MMT), Peak oxygen uptake (VOpeak), Peak power output (PO peak), Wheelchair Circuit ability, physical strain and performance.

1.      All physical parameters had significant improvements over time.

2.      PO peak improved between t1 and t2 and t2 and t3 (p<0.001). Maximum VO2 peak improved between t1 and t2 (p<0.001) and t2 and t3 (p=0.046). MMT also improved between t1 and t2 (p=0.018), and t2 and t3 (p=0.014).

3.      Wheelchair circuit scores had significant improvements over time as well.

4.      Wheelchair circuit ability improved between t1 and t2 (p<0.001) and t2 and t3 (p=0.013). Performance time also improved between t1 and t2 (p<0.001) and t2 and t3 (p=0.002). Physical strain improved between t1 and t2 and t2 and t3 (p=0.001).

Qi et al. 2015

China

Pre-Post

N=11

Population: Mean age: 42.1 yr; Gender: males=8, females=3; Level of Injury: paraplegia (T6-L1)=11; Severity of injury: AIS A=8, AIS B=1, unspecified=2; Mean time since injury: 10.4 yr.

Intervention: Patients completed three sets of 3 min wheelchair propulsion trials at different speeds; a self-selected comfortable speed, 1 ms, 1.3 ms and 1.6 ms with a 5 min rest period between each trial. After a 15 min break, patients then completed a graded exercise trial at a constant speed of 1 ms with a work load set at 10 W and increasing by 5 W every 1 min until exhaustion. Outcome measures were performed during each trial with perceived rate of exertion for respiration and for local shoulder and arms exertion.

Outcome Measures: Ratings of perceived exertion (RPE) according to 15-point Borg Scale, Oxygen uptake (VO2), Carbon dioxide output (VCO2), Heart rate, Ventilation volume.

1.     Propulsion at 1.6 ms resulted in significantly higher levels of VO2 Peak output, RPE Respiration and ventilation volume compared to propulsion at 1ms and at self-selected speed (all p<0.05).

2.     No significant differences were found between RPE Respiration and Arm Exertion at different VO2 Peak levels during the graded exercise trial.

3.     No significant differences were reported between trials for RPE Respiration and RPE Arm Exertion.

de Groot et al. 2007

Netherlands

Pre-Post

N=80

Population: Mean age: 39.4 yr; Gender: males=61, females=19; Mean weight: 72.9 kg; Level of injury: tetraplegic=18, paraplegic=62.

Intervention: Patients with SCI were tested with wheelchair exercise tests at start of inpatient rehabilitation (T1), 3 mo post (T2), at discharge (T3) and 1 year after rehabilitation (T4) to determine whether mechanical efficiency (ME) relates to wheelchair propulsion capacity and wheel chair performance tasks. Testing was done in a standard w/c, and included two 3 min submaximal steady state w/c exercises on treadmills, a peak aerobic test and four standardized w/c performance tasks (figure-of-eight, 15 m sprint, propelling on treadmill with 3% slope, propelling on a treadmill with 6% slope for 8 sec.

Outcome Measures: Energy expenditure (En), Respiratory exchange ratio (RER), Mechanical efficiency (ME), Peak power output (POpeak), Performance time score and physical strain score.

1.     ME showed a significant relationship with POpeak (p≤0.002) where a 1% higher ME related to a 1.6-2.2 W higher POpeak.

2.     A significant relationship was found between the ME and POpeak, and the sum of performance time in exercise block 2 only of the sum of the performance time of a 15-m sprint and for figure-of-eight in exercise block 2 only (p=0.02) when correcting for lesion level, VO2peak, ME was not related to the physical strain (%HRR, calculated for the 3% and 6% slope tests) at either one of the two exercise blocks (B1: p=0.56; B2: p=0.85).

Dallmeijer et al. 2005

Netherlands

Pre-Post

N=132

Population: Mean age: 39.4 yr; Gender: males=100, females=32; Mean weight: 72.9 kg; Level of injury: tetraplegic=37, paraplegic=95; Mean time since injury 269 days.

Intervention: Patients were investigated at start of active rehabilitation (T1), 3 mo (T2) and end of clinical rehabilitation (T3) to describe the course of wheelchair propulsion capacity (WPC). WPC was measured as maximal power output achieved in a maximal wheelchair exercise test on treadmill.

Outcome Measures: Maximal power output (POmax).

1.     The mean (modeled) POmax for the whole group was 30.6 W at t1, and 39.3 W and 44.3 W, at t2 and t3, respectively (p=0.000).

2.      POmax increased significantly between t1 and t2 *8.7 W; 28%) and between t1 and t3 (13.7 W; 45%).

3.      Persons with paraplegia had (on average) a 21.9W higher POmax than persons with tetraplegia (β=21.9) (p=0.000).

4.      Persons with incomplete lesions had (on average) a 5.4 W higher POmax than persons with complete lesions (β =5.4) (p=0.043).

5.      Changes in POmax depend on age and gender; younger (β=-0.254) (p=0.026) and male persons (β=7.235) (p=0.021) showed larger increases in POmax than older and Females participants.

6.      The inability to perform the test at t1 was controlled; this control variable was highly significant, showing on average a 14.5 W (p=0.000) lower POmax for subjects who were not able to perform the test at t1 compared with those who were able to do so.

Rodgers et al. 2001

USA

Pre-Post

N=19

Population: Mean age: 44 yr; Gender: males=16, females=3; Mean height: 174.5 cm; Mean weight: 79.1 kg; Injury etiology: SCI=15, spina bifida=1, multi-trauma=2, bilateral tarsal tunnel syndrome=1; Mean duration of manual w/c use: 17 yr.

Intervention: Participants who were manual wheel chair users >1 yr took part in supervised therapeutic exercise (strengthening of posterior deltoids, infraspinatus, teres minor, rhomboids, middle trapezius, erector spinae, biceps and wrist extensors muscles, stretching and aerobic exercise using w/c seated rowing machine) 3x/wk for 6 wk. Pre- and post-tests included 1) a maximal graded exercise test (GXT) where participants rested for 6 min, then propelled for 3 min at a rate to 3 km/h after which a load of 0.3 kg was added every 3 min until the rate of propulsion could no longer be maintained and 2) a fatigue test which was the same as the GXT except the load added was the maximum load; participants propelled until volitional exhaustion. All pre-post testing was completed on a prototype w/c ergometer with 22” hand rim and no wheel camber.

Outcome Measures: Handgrip strength (average of 3 measures of dominant hand), heart rate, exercise load changes, kinetic and kinematic data using 3 Peak 3D CCD camera and video system, a PY6-4 force/torque transducer, a potentiometer and a 3D-linked segment model, handrim kinetics, propulsion temporal data, Oxygen Update (VO2), Metabolic Economy.

1.     Exercise load significantly increased for all strengthening activities (p<0.01).

2.     Handgrip strength measures were unchanged.

3.     Wheelchair propulsion stroke frequency significantly decreased following training (p=0.039) as well as power output (p=0.012).

4.     Significant increase with training in shoulder flexion/extension (p=0.013), maximum elbow extensions (p=0.03) and trunk flexion (p=0.001).

5.     Of wheelchair kinetic measures, only propulsive moment (Mz) significantly increased with training (p=0.010), showing 14% improvement in propulsive moment.

6.     Wrist extension only joint kinetic measure to significantly increase after training (p=0.033).

7.     Trunk flexion/extension ROM and wrist flexion moment both significantly increased with fatigue following training (p<0.05).

Discussion

Kilkens et al. (2005) investigated the longitudinal changes in manual wheelchair skill performance and parameters for physical capacity of people with SCI at the beginning of their inpatient rehabilitation, at three months and at point of discharge. The wheelchair circuit consisted of eight standardized tasks in a fixed sequence on a treadmill, hard and soft surface. The physical capacity parameters included upper extremity muscle strength, peak oxygen uptake and peak power output (PO peak). Their study found a significant relationship between upper extremity strength and PO peak as parameters of physical capacity that influence wheelchair propulsion performance during inpatient rehabilitation of individuals with SCI.

Dallmeijer et al. (2005) tracked 132 participants across eight SCI rehabilitation centres to describe the changes that occurred in relation to wheelchair propulsion capacity (WPC) from the start of rehabilitation, three months post and at discharge. An overall improvement of 45% in WPC, as measured by Maximum Power Output (POmax) was found over the full course of rehabilitation, with significantly higher POmax being noted for participants with incomplete lesions, participants who were younger, and participants who were male. The authors suggest that these findings can help guide clinical intervention related to WPC, individualizing intervention based on these characteristics. However, the course of intervention related to WPC during rehabilitation was not described; it is unclear if there was a standard approach to intervention.

deGroot et al. 2007 examined mechanical efficiency (ME) of wheelchair propulsion, of people with SCI at the start of their rehabilitation, three months post, at discharge and one year post discharge. They are hypothesizing that higher mechanical efficiency, which they attributed to an improved propulsion technique, would show higher peak power outputs (POpeak), better performance times and lower percentage heart rate reserve (%HHR). They found that ME was significantly related to wheelchair propulsion capacity as measured by POpeak, and to the performance time of two wheelchair performance tasks, during rehabilitation and one year post discharge. The authors attributed the higher ME indirectly to propulsion technique, but no data was presented related to participants’ propulsion technique.

Rodgers et al. (2001) hypothesized that a program which combines stretching and strengthening of the muscles critical to propulsion as well as aerobic training would result in more efficient wheelchair propulsion. The supervised training program was completed three times per week for six weeks. Pre and post testing found the only significant wheelchair kinetic change was the propulsive moment, which represented a 14% improvement. The authors suggest that this finding in conjunction with the lack of change noted in the hand rim peak forces and a significant decrease in stroke frequency indicate biomechanical efficiency was improved without increasing stresses on the upper extremity joints. The authors suggest that the findings of significant increases in three kinematic measures (shoulder flexion/extension, maximum elbow extension and trunk flexion) can augment propulsion, especially at times of fatigue.

Qi et al. (2015) explored the relationship between perceived rate of exertion and physical capacity during typical mobility activities. Eleven people with a spinal cord injury level lower than T6 completed propulsion testing on a treadmill in their own wheelchairs, at three specified rates of speed which the authors equated to three different mobility activities; a self-selected comfortable speed at 1ms equated to the minimal safe speed to cross a street with traffic lights, 1.3 ms equated to typical able bodied walking speed, and 1.6ms equated to the upper limit of a self-selected speed. A final test of propulsion was completed using the first test speed with increasing resistance until exhaustion. The authors found that most participants chose a propulsion speed of 1.1 ms as a comfortable speed, which corresponded to approximately 53% VO2peak and an average heart rate of 104 beats per minute (0.69% HRmax). They also found that there were no significant differences between the rate of perceived exertion for respiration and arm. The authors indicate these findings suggest that self-selected propulsion speeds of low and moderate rates, which correspond to typical daily life mobility activities, can provide cardiovascular conditioning.

In their random control study, Gauthier et al. (2018) compared the feasibility, safety and preliminary effectiveness of home-based high intensity interval training (HIIT) and moderate intensity continuous training (MICT) programs in people with spinal cord injury who use manual wheelchairs. Despite the absence of statistically significant cardiovascular and upper extremities strength changes, subjective improvements in general health, including cardiorespiratory fitness were reported by participants. All participants indicated they would recommend their program to others with SCI. The authors noted statistically significant improvements in VO2peak in two individuals in the MICT group who were not regularly exercising prior to the training. They suggested that training could have the biggest impact in sedentary participants as it was the least active individuals at baseline who showed the greatest improvements in UE muscle strength. One participant in the HIIT group dropped out due to shoulder pain and another reported a significant increase. The authors determined that both training programs were feasible and safe in the community but the influence of their weekly follow up calls on participantion in the training was not evaluated. The authors did highlight that programs should be individualized and attention paid to the potential development of shoulder pain with a HIIT, especially in participants with pre-existing shoulder pain.

van der Scheer et al. (2016) investigated the effects a of twice a week, low-intensity wheelchair training program with inactive individuals who had been living with spinal cord injury greater than ten years, to determine if improved cardiovascular and propulsion outcomes could be achieved. In, the results of this randomized control study showed no significant training effects between the exercise and the control group in any of the measures. The authors concluded that this dosage of exercise is insufficient for substantial improvements in an inactive population with long-term SCI. However, it was queried whether outcomesof this study have been influenced by a relative decline in the control group due to drop outs. It is suggested that further research is needed to generalize these outcomes to the broader population.

Torhaug et al. (2016) investigated the effect of maximal bench press strength training on wheelchair propulsion work economy (WE), with individuals with paraplegia. The authors reported that participants in the intervention group (n=9) demonstrated a 17.3% improvement in WE during wheelchair ergometry, as indicated by a reduction in in VO2 consumption. However, there were no changes in the other outcome measures (pulmonary ventilation or respiratory exchange ratio). The authors suggest that based on these results, a strength training regime of high load and few repetitions can lead to improved mobilization force during the concentric phase of wheelchair propulsion, and, despite no endurance-training component to the intervention, result in lower oxygen cost and more efficient wheelchair work economy. Two participants withdrew from the study because of shoulder pain. The authors recommend beginning the training at a lower intensity in those with any latent shoulder disease, however the outcomes of this suggested change were not tested inthis study. Due to the small number of participants, that dropouts occurred due to shoulder pain, and 1 of the 3 otucomes measured changed, it is felt that caution is needed in extrapolating these findings t the larger population.

Conclusions

There is level 2 evidence (from 1 cohort study by Kilkens et al. 2005; from one prospective controlled study by Torhaug et al. 2016; from three pre-post study by deGroot et al. 2007; Rodgers et al. 2001; Dallmeijer et al. 2005) that exercise training at physical capacity and upper extremity strengthening influence wheelchair propulsion performance.

There is level 1b evidence (from 1 RCT: van der Scheer et al. 2016) that twice weekly, low intensity wheelchair propulsion training is not adequate to affect fitness, however there is level 4 evidence (from one pre-post study; Qi et al. 2015) suggesting that manual wheelchair propulsion at low (1ms) and moderate (1.3ms) propulsion rates during typical daily life mobility activities contribute to cardiovascular conditioning.

There is level 2 evidence (from 1 RCT: Gauthier et al. 2018) evidence that community-based programs are feasible and safe training programs for manual wheelchair users.