Reliability and Validity of Subjective Measures of Aerobic Intensity in Adults With Spinal Cord Injury: A Systematic Review

Differential relationships between physical activity and pain phenotypes in individuals with spinal cord injury

BACKGROUND

Chronic pain affects 70% of individuals with spinal cord injury (SCI) and leads to declines in health and quality of life. Neuropathic and nociceptive pain are phenotypes derived from different mechanisms that contribute to pain perception. The objective of this research was to investigate differential pain responses to moderate-to-vigorous physical activity (MVPA) in two chronic pain phenotypes: neuropathic and nociceptive pain.

METHODS

Community-based physical activity levels were collected for one week in 17 individuals with SCI using a wrist-worn accelerometer, and daily pain ratings were assessed and categorized by phenotype. Physical activity levels were summarized to calculate minutes of MVPA. Correlational analyses were conducted to compare relationships between pain intensity and MVPA across individual participants and between pain phenotype groups.

RESULTS

The neuropathic pain group revealed significant negative correlation between MVPA and pain intensity. In the nociceptive pain group, there was no significant correlation between MVPA and pain intensity. Further analysis revealed two subgroups of positive (N = 4) and negative (N = 3) correlations between MVPA and pain intensity. Pain location differed between the subgroups of nociceptive pain. Individuals with negative correlation experienced neck and upper back pain, whereas individuals with positive correlation experienced unilateral upper extremity pain.

CONCLUSION

Differential relationships exist between pain phenotypes and MVPA in individuals with SCI. Pain location differed between the subgroups of nociceptive pain, which we presume may indicate the presence of nociplastic pain in some individuals. These results may contribute to the advancement of personalized pain management by targeting non-pharmacological interventions for specific pain phenotypes.Trial registration: ClinicalTrials.gov identifier: NCT05236933..

Biomarkers for predicting the severity of spinal cord injury by proteomic analysis

Purpose

Currently, there is a shortage of the protein biomarkers for classifying spinal cord injury (SCI) severity. We attempted to explore the candidate biomarkers for predicting SCI severity.

Methods

SCI rat models with mild, moderate, and severe injury were constructed with an electro-mechanic impactor. The behavior assessment and pathological examinations were conducted before and after SCI. Then, quantitative liquid chromatography-mass spectrometry (LC-MS/MS) was performed in spinal cord tissues with different extents of injury. The differentially expressed proteins (DEPs) in SCI relative to controls were identified, followed by Mfuzz clustering, function enrichment analysis, and protein-protein interaction (PPI) network construction. The differential changes of candidate proteins were validated by using a parallel reaction monitoring (PRM) assay.

Results

After SCI modeling, the motor function and mechanical pain sensitivity of SCI rats were impaired, dependent on the severity of the injury. A total of 154 DEPs overlapped in the mild, moderate, and severe SCI groups, among which 82 proteins were classified in clusters 1, 2, 3, 5, and 6 with similar expression patterns at different extents of injury. DEPs were closely related to inflammatory response and significantly enriched in the IL-17 signaling pathway. PPI network showed that Fgg (Fibrinogen gamma chain), Fga (Fibrinogen alpha chain), Serpinc1 (Antithrombin-III), and Fgb (Fibrinogen beta chain) in cluster 1 were significant nodes with the largest degrees. The upregulation of the significant nodes in SCI samples was validated by PRM.

Conclusion

Fgg, Fga, and Fgb may be the putative biomarkers for assessing the extent of SCI.

Estimation of peak oxygen consumption in individuals with spinal cord injury patients using multiple linear regression analysis: a preliminary study

PURPOSE

This study aims to develop a regression model to estimate peak oxygen consumption (VO2peak) in individuals with spinal cord injury (SCI) by employing different variables.

METHODS

In this study, 34 participants were divided into two groups: 19 with cervical injury (CI) and 15 with thoracic injury (TI). Key measurements included VO2peak and related factors such as age, height, weight, body mass index (BMI), fat-free mass, body fat percentage, limb and trunk circumferences, spinal cord independence (SCIM III), Korean activities of daily living (K-ADL), and respiratory functions (forced vital capacity (FVC), peak expiratory flow (PEF), and maximum voluntary ventilation (MVV)). Statistical analyses were conducted using forward selection regression to examine the relationships between these variables.

RESULTS

Height, calf circumference, SCIM III score, and PEF were key variables in all patients with SCI (TSCI). For patients with CI, the key variables were height, calf circumference, and MVV, whereas for patients with TI, the key variable was calf circumference. The average explanatory powers of the VO2peak regression model for TSCI were 70.3% (R2) and 66.2% (adjusted R2), with an average standard error of estimate (SEE) of 2.94 ml/kg/min. The average explanatory power for patients with CI was 71.7% (R2) and 66.1% (adjusted R2), with an average SEE of 1.88 ml/kg/min. The average explanatory power for patients with TI was 55.9% (R2) and 52.5% (adjusted R2), with an average SEE of 3.41 ml/kg/min. There was no significant difference between the VO2peak measured and predicted VO2peak for each type of injury.

CONCLUSION

The regression model for estimating VO2peak in SCI patients in this preliminary study is as follows: TSCI=39.684-0.144×(Height)-0.513×(Calf)+0.136×(SCIM III)+1.187×(PEF), CI=38.842-0 .158×(Height) - 0.371×(Calf)+0.093×(MVV), TI=42.325-0.813×(Calf).

Exercise prescription for persons with spinal cord injury: a review of physiological considerations and evidence-based guidelines

Persons with spinal cord injury (SCI) experience gains in fitness, physical and mental health from regular participation in exercise and physical activity. Due to changes in physiological function of the cardiovascular, nervous, and muscular systems, general population physical activity guidelines and traditional exercise prescription methods are not appropriate for the SCI population. Exercise guidelines specific to persons with SCI recommend progressive training beginning at 20 min of moderate to vigorous intensity aerobic exercise twice per week transitioning to 30 min three times per week, with strength training of the major muscle groups two times per week. These population-specific guidelines were designed considering the substantial barriers to physical activity for persons with SCI and can be used to frame an individual exercise prescription. Rating of perceived exertion (i.e., perceptually regulated exercise) is a practical way to indicate moderate to vigorous intensity exercise in community settings. Adapted exercise modes include arm cycle ergometry, hybrid arm-leg cycling, and recumbent elliptical equipment. Body weight-supported treadmill training and other rehabilitation modalities may improve some aspects of health and fitness for people with SCI if completed at sufficient intensity. Disability-specific community programs offer beneficial opportunities for persons with SCI to experience quality exercise opportunities but are not universally available.

Intervention Design of High-Intensity Interval Training in Individuals With Spinal Cord Injury: Narrative Review and Future Perspectives

Background

Individuals with spinal cord injury (SCI) have lower levels of physical activity compared to the nondisabled population. Exercise guidelines recommend moderate or vigorous exercise to improve cardiovascular health and reduce cardiometabolic risk factors in persons with SCI. High-intensity interval training (HIIT) is a popular exercise choice and encompasses brief periods of vigorous exercise paired with intermittent periods of recovery.

Objectives

This review describes the available literature on HIIT for individuals with SCI, including differences in protocol design and suggested areas of further investigation.

Methods

Our institution's library system performed the comprehensive search. The primary keywords and phrases used to search included spinal cord injury, high-intensity interval training, tetraplegia, paraplegia, and several other related terms.

Results

Initially 62 records were screened, and 36 were deemed outside the scope of this review. Twenty-six studies published between 2001 and 2021 fulfilled the eligibility criteria and were divided among two researchers for review and analysis. All records required persons with SCI and a standardized HIIT intervention. Study design varied widely with respect to mode of exercise, prescribed intensity, duration of performance intervals, and session duration. This variability necessitates further investigation into the specifics of a HIIT prescription and the associated outcomes for persons with SCI.

Conclusion

Standardization of HIIT protocols may lead to more robust conclusions regarding its effects on cardiorespiratory fitness as well as mitigation of cardiometabolic risk factors. Meta-analyses will eventually be needed on proper dosing and session parameters to improve cardiorespiratory fitness and cardiometabolic risk factors.

Exercise and aerobic capacity in individuals with spinal cord injury: A systematic review with meta-analysis and meta-regression

BACKGROUND

A low level of cardiorespiratory fitness [CRF; defined as peak oxygen uptake ([Formula: see text]O2peak) or peak power output (PPO)] is a widely reported consequence of spinal cord injury (SCI) and a major risk factor associated with chronic disease. However, CRF can be modified by exercise. This systematic review with meta-analysis and meta-regression aimed to assess whether certain SCI characteristics and/or specific exercise considerations are moderators of changes in CRF.

METHODS AND FINDINGS

Databases (MEDLINE, EMBASE, CENTRAL, and Web of Science) were searched from inception to March 2023. A primary meta-analysis was conducted including randomised controlled trials (RCTs; exercise interventions lasting >2 weeks relative to control groups). A secondary meta-analysis pooled independent exercise interventions >2 weeks from longitudinal pre-post and RCT studies to explore whether subgroup differences in injury characteristics and/or exercise intervention parameters explained CRF changes. Further analyses included cohort, cross-sectional, and observational study designs. Outcome measures of interest were absolute (A[Formula: see text]O2peak) or relative [Formula: see text]O2peak (R[Formula: see text]O2peak), and/or PPO. Bias/quality was assessed via The Cochrane Risk of Bias 2 and the National Institute of Health Quality Assessment Tools. Certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Random effects models were used in all meta-analyses and meta-regressions. Of 21,020 identified records, 120 studies comprising 29 RCTs, 67 pre-post studies, 11 cohort, 7 cross-sectional, and 6 observational studies were included. The primary meta-analysis revealed significant improvements in A[Formula: see text]O2peak [0.16 (0.07, 0.25) L/min], R[Formula: see text]O2peak [2.9 (1.8, 3.9) mL/kg/min], and PPO [9 (5, 14) W] with exercise, relative to controls (p < 0.001). Ninety-six studies (117 independent exercise interventions comprising 1,331 adults with SCI) were included in the secondary, pooled meta-analysis which demonstrated significant increases in A[Formula: see text]O2peak [0.22 (0.17, 0.26) L/min], R[Formula: see text]O2peak [2.8 (2.2, 3.3) mL/kg/min], and PPO [11 (9, 13) W] (p < 0.001) following exercise interventions. There were subgroup differences for R[Formula: see text]O2peak based on exercise modality (p = 0.002) and intervention length (p = 0.01), but there were no differences for A[Formula: see text]O2peak. There were subgroup differences (p ≤ 0.018) for PPO based on time since injury, neurological level of injury, exercise modality, and frequency. The meta-regression found that studies with a higher mean age of participants were associated with smaller changes in A[Formula: see text]O2peak and R[Formula: see text]O2peak (p < 0.10). GRADE indicated a moderate level of certainty in the estimated effect for R[Formula: see text]O2peak, but low levels for A[Formula: see text]O2peak and PPO. This review may be limited by the small number of RCTs, which prevented a subgroup analysis within this specific study design.

CONCLUSIONS

Our primary meta-analysis confirms that performing exercise >2 weeks results in significant improvements to A[Formula: see text]O2peak, R[Formula: see text]O2peak, and PPO in individuals with SCI. The pooled meta-analysis subgroup comparisons identified that exercise interventions lasting up to 12 weeks yield the greatest change in R[Formula: see text]O2peak. Upper-body aerobic exercise and resistance training also appear the most effective at improving R[Formula: see text]O2peak and PPO. Furthermore, acutely injured, individuals with paraplegia, exercising for ≥3 sessions/week will likely experience the greatest change in PPO. Ageing seemingly diminishes the adaptive CRF responses to exercise training in individuals with SCI.

REGISTRATION

PROSPERO: CRD42018104342.

The Buffalo Concussion Treadmill and Bike Tests in People With Mild-to-Moderate Traumatic Brain Injury: An Exploratory Clinical Audit

OBJECTIVE

To assess the performance on the Buffalo Concussion Treadmill and Bike Tests in nonathletic people following a mild-to-moderate traumatic brain injury.

SETTING

An outpatient rehabilitation clinic.

PARTICIPANTS

Forty-nine patients with mild-to-moderate traumatic brain injury who underwent the Buffalo Concussion Treadmill or Bike Test as usual clinical care.

DESIGN

A retrospective clinical audit.

MAIN MEASURES

Demographics and brain injury-specific clinical data, Depression Anxiety Stress Scale; Rivermead Post-Concussion Symptom Questionnaire, and performance outcomes on the Buffalo Concussion Treadmill or Bike Test.

RESULTS

Forty-nine patients (mean age: 33.7 ± 13.0 years), on average 56.2 ± 36.4 days post-injury, completed the Buffalo Concussion Treadmill or Bike Test. Fourteen patients stopped the test due to symptom exacerbation with a mean test duration of 8.1 ± 4.5 minutes, reaching an age-predicted maximum heart rate of 72.9% ± 12.4% and reporting a rating of perceived exertion of 13.4 ± 2.2. Those who terminated the test for other reasons had a significantly longer test duration (14.0 ± 4.7 minutes, P = .01), with a higher age-predicted maximum heart rate (83.3% ± 12.8%, P = .01) and rating of perceived exertion (17.0 ± 2.5, P = .01). Within the group who stopped for other reasons, 10 were due to symptoms deemed unrelated to the injury at the time of the test and 2 were stopped by the therapist for safety reasons. A significant but weak correlation between heart rate and rating of perceived exertion existed only for those who terminated the test for other reasons ( r = 0.38, P = .02). Overall, a shorter test duration was associated with higher scores of both self-reported depression ( r = -0.41, P < .01) and late postconcussion symptoms ( r = -0.40, P < .01).

CONCLUSION

The Buffalo Concussion Treadmill or Bike Test can be used in the nonathletic mild-to-moderate traumatic brain injury population to differentiate between those who experience symptom exacerbation during exercise and those who do not based on symptom exacerbation, test duration, and poor perception of exertion. Further research is required to determine whether other reasons for test termination are related to the injury.

Dissonance in views between healthcare professionals and adults with a spinal cord injury with their understanding and interpretation of exercise intensity for exercise prescription

Objectives

To evaluate the difference between healthcare professionals (HCPs) and adults with spinal cord injury (SCI) in Asia regarding knowledge and interpretation of 'exercise intensity' for aerobic exercise prescription.

Methods and study design

A survey was distributed to practising HCP and adults with SCI. It was completed in participants' local language on topics related to the importance of exercise frequency, intensity, time and type; methods for monitoring and terms related to exercise intensity prescription. χ² analysis was used to detect differences in HCP or those with SCI.

Results

121 HCP and 107 adults with an SCI ≥1 years (C1-L4) participated. Responses revealed 61% of all HCP ranked 'intensity' being most important whereas only 38% respondents from the SCI group ranked it as high importance (p=0.008). For those with SCI, 'frequency' was most important (61%) which was significantly higher than the 45% selected by HCPs (p=0.030). Of the 228 respondents on average only 34% believed that the terms, 'moderate' and 'vigorous' provided enough information for aerobic exercise intensity prescription. HCP most often used HR methods compared with the SCI group (90% vs 54%; p<0.01). Both groups frequently used the subjective measures of exercise intensity, for example, Ratings of Perceived Exertion (8%3 vs 76% for HCP and SCI), HCP also frequently used speed (81%) and SCI also frequently relied on 'the affect' or feelings while exercising (69%).

Conclusions

These differences must be considered when developing clinical-practice exercise guidelines and health referral educational pathways for adults with SCI in Asia.

Preliminary feasibility and acute physiological effects of a single session of upper limb vibration training for persons with spinal cord injury

CONTEXT

Strong upper limb musculature is essential for persons with spinal cord injury (SCI) to operate a manual wheelchair and live independently. Targeted upper limb vibration may be a viable exercise modality to build muscle efficiently while eliminating some of the barriers associated with exercise for persons with SCI.

OBJECTIVE

The purpose of this study was to assess preliminary feasibility of completing a single exercise session of upper limb vibration and compare the acute physiological effects to a single session of standard dumbbell resistance exercise.

METHODS

Individuals with SCI performed seven upper limb exercises (1) isometrically using a vibrating dumbbell at 30 Hz for 60 s (n = 22) and (2) using a standard isotonic resistance protocol (n = 15).

RESULTS

Nineteen (86.4%) of 22 participants were able to perform all vibration exercises at 30 Hz but hold time success rates varied from 33% (side flies and front raises) to 95% (internal rotation). No significant differences were found between vibration exercise and standard resistance protocol for blood lactate, power output, and heart rate (P > 0.05). Perceptions of the training were positive, with most participants (>70%) expressing interest to train with vibration in the future.

CONCLUSIONS

Vibration training was not feasible for all participants, suggesting an individualized approach to starting weight and progression may be necessary. Similar acute physiological changes were seen between vibration exercise and standard resistance protocol, suggesting they could have similar benefits. Additional research is needed to determine if vibration exercise is feasible and beneficial to incorporate into a long-term training program.

Knowledge Gaps in Biophysical Changes After Powered Robotic Exoskeleton Walking by Individuals With Spinal Cord Injury—A Scoping Review

In addition to helping individuals with spinal cord injury (SCI) regain the ability to ambulate, the rapidly evolving capabilities of robotic exoskeletons provide an array of secondary biophysical benefits which can reduce the complications resulting from prolonged immobilization. The proposed benefits of increased life-long over-ground walking capacity include improved upper body muscular fitness, improved circulatory response, improved bowel movement regularity, and reduced pain and spasticity. Beyond the positive changes related to physical and biological function, exoskeletons have been suggested to improve SCI individuals' quality of life (QOL) by allowing increased participation in day-to-day activities. Most of the currently available studies that have reported on the impact of exoskeletons on the QOL and prevention of secondary health complications on individuals with SCI, are of small scale and are heterogeneous in nature. Moreover, few meta-analyses and reviews have attempted to consolidate the dispersed data to reach more definitive conclusions of the effects of exoskeleton use. This scoping review seeks to provide an overview on the known effects of overground exoskeleton use, on the prevention of secondary health complications, changes to the QOL, and their effect on the independence of SCI individuals in the community settings. Moreover, the intent of the review is to identify gaps in the literature currently available, and to make recommendations on focus study areas and methods for future investigations.

Should We Trust Perceived Effort for Loading Control and Resistance Exercise Prescription After ACL Reconstruction?

CONTEXT

The rating of perceived effort (RPE) is a common method used in clinical practice for monitoring, loading control, and resistance training prescription during rehabilitation after rupture and anterior cruciate ligament reconstruction (ACLR). It is suggested that the RPE results from the integration of the afferent feedback and corollary discharge in the motor and somatosensory cortex, and from the activation of brain areas related to emotions, affect, memory, and pain (eg, posterior cingulate cortex, precuneus, and prefrontal cortex). Recent studies have shown that rupture and ACLR induce neural adaptations in the brain commonly associated with the RPE. Therefore, we hypothesize that RPE could be affected because of neural adaptations induced by rupture and ACLR.

STUDY DESIGN

Clinical review.

LEVEL OF EVIDENCE

Level 5.

RESULTS

RPE could be directly altered by changes in the activation of motor cortex, posterior cingulate cortex, and prefrontal cortex. These neural adaptations may be induced by indirect mechanisms, such as the afferent feedback deficit, pain, and fear of movement (kinesiophobia) that patients may feel after rupture and ACLR.

CONCLUSION

Using only RPE for monitoring, loading control, and resistance training prescription in patients who had undergone ACLR could lead to under- or overdosing resistance exercise, and therefore, impair the rehabilitation process.

STRENGTH-OF-RECOMMENDATION TAXONOMY

3C.

The ability of heart rate or perceived exertion to predict oxygen uptake varies across exercise modes in persons with tetraplegia

STUDY DESIGN

Descriptive study.

OBJECTIVES

To examine grouped and intra-individual relationships between 1) exercise intensity and heart rate (EI-HR); 2) EI and oxygen uptake (EI-VO₂); 3) VO₂ and HR (VO₂-HR); and 4) perceived exertion and VO₂ (PE-VO₂) in persons with tetraplegia (C4/5-C8) during different modes of exercise.

SETTING

Community in Winnipeg, Canada.

METHODS

Participants exercised at 3 graded intensities during arm ergometry (ERG), wheeling indoors on cement (MWC), or hand-cycling outdoors (HC). EI (Watts, km/hr) and VO₂, HR and PE were recorded.

RESULTS

22 persons completed ERG, 14/22 also completed MWC and 5/22 completed ERG, MWC and HC. Regression analysis of grouped data showed a significant relationship between EI-VO₂ but not for EI-HR or HR-VO₂. Intra-individual analyses showed a strong correlation (r or ρ > 0.7) for VO₂-HR for 16/22 during ERG. In the participants completing multiple exercise modes, a strong VO₂-HR relationship was present in 12/14 in ERG, but in only 6/14 in MWC. The 5 persons exercising with all 3 modes had a strong HR-VO₂ relationship in 5/5 for ERG, 2/5 in MWC and 1/5 in HC. A strong relationship for PE-VO₂ was observed in a higher proportion of participants (versus HR-VO₂) during MWC (9/14) and HC (2/4).

CONCLUSION

Within the same individual, the HR-VO₂ relationship varies across modes, despite exercising over similar ranges of steady-state VO₂. HR appears less able to predict VO₂ compared to PE. Based on these new findings, systematic investigation of the HR-VO₂ relationship across modes of exercise in tetraplegia is warranted.

Effects of a Tailored Physical Activity Intervention on Cardiovascular Structure and Function in Individuals With Spinal Cord Injury

Background

Spinal cord injury (SCI) leads to a loss of descending motor and sympathetic control below the level of injury (LOI), which ultimately results in chronically altered cardiovascular function and remodeling. While supervised, laboratory-based exercise training can generate cardiovascular adaptations in people with SCI, it is unknown whether behavioral community-based interventions effectively generate such adaptations for individuals with SCI.

Objective

Examine the effects of a tailored behavioral physical activity (PA) intervention on cardiac and vascular structure and function in individuals with SCI.

Methods

In this randomized controlled trial, 32 participants with SCI (18-65 years, SCI >1 year) were assigned to PA (8-week behavioral intervention) or control (CON) groups. At baseline and postintervention, measures of resting left ventricular (LV) structure and function, carotid intima-media thickness and pulse-wave velocity were assessed with ultrasound and tonometry.

Results

Twenty-eight participants completed the study (n = 14/group). Across the full study cohort there were no significant changes in indices of LV or vascular structure and function, despite notable improvements in peak power and oxygen uptake in the PA group. However, in a subanalysis for LOI, individuals in the PA group with LOIs below T6 had evidence of altered LV geometry (ie, increased LV internal diameter, reduced sphericity index and relative wall thickness; group × time P < 0.05 for all), which was not seen in individuals with higher LOIs at or above T6.

Conclusion

An 8-week behavioral PA intervention appears to promote adaptations in cardiac geometry more readily in individuals with lower level SCI than those with higher-level SCI.

Adipose-derived stromal cells improve functional recovery after spinal cord injury through TGF-β1/Smad3/PLOD2 pathway activation

Transplantation of mesenchymal stromal cells (MSCs) improves functional recovery in experimental models of spinal cord injury (SCI), but the mechanism is not fully understood. Activation of procollagen-lysine, 2-oxoglutarate 5-dioxygenase 2 (PLOD2), a collagen-modifying enzyme, reportedly follows MSC transplantation in an SCI animal model. We investigated the regulation of PLOD2 expression and its potential contribution to the neuroprotective effects of adipose-derived stromal cells (ADSCs) following mechanical injury to neurons in vitro and SCI in vivo. ADSCs enhanced wound healing in vitro and promoted functional recovery after their implantation near injury sites in a rat SCI model. These effects correlated with upregulation of PLOD2, MAP2, NSE and GAP43, and downregulation of GFAP, which is indicative of improved neuronal survival and axonal regeneration as well as reduced glial scar formation. The neurorestorative effect of ADSCs was weakened after inhibition of PLOD2 expression. ADSCs appeared to induce PLOD2 upregulation via TGF-β1 secretion, as ADSC-mediated PLOD2 expression, neuronal survival, and functional recovery after SCI were largely prevented by SB431542, a TGF-(1 receptor inhibitor. These findings indicate that ADSCs reduce lesion size and promote functional recovery after SCI mainly through activation of a TGF-β1/P-Samd3/PLOD2 pathway in spinal cord neurons.

Comparison of two Borg exertion scales for monitoring exercise intensity in able-bodied participants, and those with paraplegia and tetraplegia

STUDY DESIGN

Cross-sectional cohort study.

OBJECTIVES

To compare ratings of perceived exertion (RPE) on Borg's 6-20 RPE scale and Category Ratio 10 (CR10) in able-bodied (AB) participants during upper and lower body exercise, and recreationally active participants with paraplegia (PARA) and athletes with tetraplegia (TETRA) during upper body exercise only.

SETTING

University and rehabilitation centre-based laboratories in UK and Netherlands.

METHODS

Twenty-four participants were equally split between AB, PARA, and TETRA. AB performed maximal tests using cycle (AB-CYC) and handcycle (AB-HC) ergometry. PARA and TETRA performed maximal handcycle and wheelchair propulsion tests, respectively. Oxygen uptake (V̇O₂) and blood lactate concentration were monitored throughout. RPE was rated each stage on Borg's RPE scale and CR10. Thresholds were identified according to log-V̇O₂ plotted against log-blood lactate (LT₁), and 1.5 mmol L^-1 greater than LT₁ (LT₂).

RESULTS

RPE from both scales were best fit against each other using a quadratic model, with high goodness of fit between scales that was independent of exercise mode and participant group (range R²: 0.965-0.970, P < 0.005). Though percentage peak V̇O₂ was significantly greater in TETRA (P < 0.005), there was no difference in RPE at LT₁ or LT₂ between groups on Borg's RPE scale or CR10.

CONCLUSION

Strong association between Borg's RPE scale and CR10 suggests they can be used interchangeably. RPE at lactate thresholds were independent of mode of exercise and level of spinal cord injury. However, inter-individual variation precludes from making firm recommendations about using RPE for prescribing homogenous exercise intensity.

Effect of wheelchair-modified rowing exercise on cardiometabolic risk factors in spinal cord injured wheelchair users: protocol for a randomised controlled trial

INTRODUCTION

Cardiovascular and metabolic diseases are a growing concern for individuals with spinal cord injury (SCI). Physical inactivity contributes to cardiometabolic morbidity and mortality in the SCI population. However, previous studies have shown mixed results regarding the effects of exercise on cardiometabolic risk factors in individuals with SCI. This discrepancy could be influenced by insufficient exercise stimuli. Recent guidelines recommend 30 min of moderate-to-vigorous intensity aerobic exercise, three times per week, for improvement in cardiometabolic health in individuals with SCI. However, to date, no studies have implemented an exercise intervention matching the new recommendations to examine the effects on cardiometabolic risk factors. Therefore, the primary objective of this study is to determine the effects of 12 weeks of wheelchair user-modified upper-body rowing exercise on both traditional (constituents of the metabolic syndrome) and novel (eg, vascular structure and function) cardiometabolic risk factors in manual wheelchair users with SCI.

METHODS AND ANALYSIS

A randomised controlled trial will compare 12 weeks of upper-body rowing exercise, 30 min three times per week, with a control group continuing their normal lifestyle. Outcome measurements will be performed immediately before (baseline), after 6 weeks (halfway), 12 weeks of training (post) and 6 months after the termination of the intervention period (follow-up). Outcomes will include inflammatory (eg, C reactive protein) and metabolic biomarkers determined from venous blood (with serum fasting insulin as primary outcome), body composition, arterial blood pressure, cardiorespiratory fitness level, brachial artery vascular structure and function and autonomic nervous system function.

ETHICS AND DISSEMINATION

This trial is reported to the Danish Data Protection Agency (J.nr. 2019-899/10-0406) and approved by the Committees on Health Research Ethics in The North Denmark Region on 12 December 2019 (J.nr. N-20190053). The principal investigator will collect written informed consent from all participants prior to inclusion. Irrespective of study outcomes, the results will be submitted to peer-reviewed scientific journals for publication.

TRIAL REGISTRATION NUMBER

NCT04390087.

Feasibility, acceptability, and preliminary efficacy of a handcycling high-intensity interval training program for individuals with spinal cord injury

Study Design:

Pilot non-randomized clinical trial

Objectives:

To examine the feasibility, acceptability and preliminary efficacy of performing handcycling high intensity interval training (HIIT) for six weeks in wheelchair users with spinal cord injury.

Setting:

Participant’s home

Methods:

Participants completed pre and post graded exercise stress tests, exercise surveys and six weeks of handcycling HIIT. The HIIT program consisted of two weekly, 25 minute supervised at-home sessions (2-3 min warm-up, then 10 intervals of cycling with a ratio of 1 minute work at 90% peak power output (PPO) to 1 minute recovery at 0-20% PPO, then 2-3 min cool-down). Real-time power output and heart rate were recorded via sensors and a bike computer. The sensor data were analyzed to evaluate training efficacy.

Results:

Seven of the 10 enrolled participants (70%) completed the study. All but one completed the required 12 sessions. The participants met at least one of the HIIT target intensity criteria in 76 out of 89 total sessions (85.4%) performed. Participants expressed a high level of enjoyment on the Physical Activity Enjoyment Scale, mean (SD) = 114.8 (11.3), and satisfaction with the overall experience. Five of the seven participants (71%) who completed the study felt an increase in endurance, function and health. Objective physiological changes showed mixed results.

Conclusions:

Six weeks of handcycling HIIT appears to be safe, feasible and acceptable. A longer HIIT work interval may be needed to elicit significant physiological responses. Future investigation of the feasibility and efficacy of differing HIIT parameters is needed.

Rehabilitation: mobility, exercise & sports; a critical position stand on current and future research perspectives

BACKGROUND

Human movement, rehabilitation, and allied sciences have embraced their ambitions within the cycle of "RehabMove" congresses over the past 30 years. This combination of disciplines and collaborations in the Netherlands has tried to provide answers to questions in the fields of rehabilitation and adapted sports, while simultaneously generating new questions and challenges. These research questions help us to further deepen our understanding of (impaired) human movement and functioning, with and without supportive technologies, and stress the importance of continued multidisciplinary (inter)national collaboration.

METHODS

This position stand provides answers that were conceived by the authors in a creative process underlining the preparation of the 6th RehabMove Congress.

RESULTS

The take-home message of the RehabMove2018 Congress is a plea for continued multidisciplinary research in the fields of rehabilitation and adapted sports. This should be aimed at more individualized notions of human functioning, practice, and training, but also of performance, improved supportive technology, and appropriate "human and technology asset management" at both individual and organization levels and over the lifespan.

CONCLUSIONS

With this, we anticipate to support the development of rehabilitation sciences and technology and to stimulate the use of rehabilitation notions in general health care. We also hope to help ensure a stronger embodiment of preventive and lifestyle medicine in rehabilitation practice. Indeed, general health care and rehabilitation practice require a healthy and active lifestyle management and research agenda in the context of primary, secondary, and tertiary prevention.IMPLICATIONS FOR REHABILITATIONContinued multidisciplinary (international) collaboration will stimulate the development of rehabilitation and human movement sciences.Notions from "human and technology asset management and ergonomics" are fundamental to rehabilitation practice and research.The rehabilitation concept will further merge into general health care and the quality there-off.

Locomotor training in people with spinal cord injury: is this exercise?

Locomotor training holds tremendous appeal to people with spinal cord injury who are wheelchair dependent, as the reacquisition of gait remains one of the most coveted goals in this population. For the last few decades this type of training has remained primarily in the clinical environment, as it requires the use of expensive treadmills with bodyweight support or complex overhead suspension tracks to facilitate overground walking. The development of powered exoskeletons has taken locomotor training out of the clinic, both improving accessibility and providing a potential option for community ambulation in people with lower limb paralysis. A question that has yet to be answered, however, is whether or not locomotor training offers a sufficiently intense stimulus to induce improvements in fitness or health. As inactivity-related secondary health complications are a major source of morbidity and mortality in people with SCI, it would be important to characterize the potential of locomotor training to not only improve functional walking ability, but also improve health-related fitness. This narrative review will summarize the key literature in this area to determine whether locomotor training challenges the cardiovascular, muscular or metabolic systems enough to be considered a viable form of exercise.

Perceived exertion responses to wheelchair propulsion differ between novice able-bodied and trained wheelchair sportspeople

OBJECTIVES

To investigate peripheral (RPE_P) and central (RPE_C) Ratings of Perceived Exertion during wheelchair propulsion in untrained able-bodied (AB) participants, and trained wheelchair rugby athletes with and without cervical spinal cord injury (CSCI).

DESIGN

Cross-sectional study.

METHODS

38 participants (AB: n=20; wheelchair rugby athletes with CSCI: n=9; without CSCI: n=9) completed an incremental wheelchair propulsion test to exhaustion on a motorised treadmill. Gas exchange measures and heart rate (HR) were collected throughout. RPE_P and RPE_C on the Category Ratio-10 were verbally recorded each minute. Blood lactate concentration ([BLa]) was determined post-test.

RESULTS

Between 50-100% peak oxygen uptake (V̇O_2peak), RPE_P was greater than RPE_C in AB (p<0.05), but not in athletes with (p=0.07) or without (p=0.16) CSCI. RPE_P was greater in AB compared to players with CSCI (Effect sizes: 1.24-1.62), as were respiratory exchange ratio (1.02±0.10 vs 0.82±0.11, p<0.05) and [BLa]_peak (7.98±2.53 vs 4.66±1.57mmol·L^-1). RPE_C was greater in athletes without CSCI compared to those with CSCI (Effect sizes: 0.70-1.38), as were HR (166±20 vs 104±15 beats·min^-1, p<0.05) and ventilation (59.2±28.8 vs 35.1±16.6L·min^-1, p=0.01).

CONCLUSIONS

RPE_P was dominant over RPE_C during wheelchair propulsion for untrained AB participants. For athletes with CSCI, lower RPE_P and RPE_C were reported at the same %V̇O_2peak compared to those without CSCI. The mechanism for this remains to be fully elucidated.

Perceptually regulated training does not influence the differentiated RPE response following 16-weeks of aerobic exercise in adults with spinal cord injury

This study investigated the effect of prolonged familiarisation with ratings of perceived exertion (RPE) on the peripheral (RPE_P) and central (RPE_C) RPE responses to moderate-vigorous exercise in adults with spinal cord injury (SCI). RPE_P and RPE_C characterise the exertion of the working musculature and cardiorespiratory systems, respectively. Nineteen participants (age, 41.4 ± 11.4 years; peak oxygen uptake, 19.2 ± 7.2 mL·kg^-1·min^-1) with chronic SCI were randomly assigned to RPE-guided (n = 11; EXP) or active control (n = 8; CON) groups. EXP performed 16-weeks of RPE-guided, supervised aerobic training for 20 min, twice weekly, at RPE 3-6 (Category-Ratio 10 scale). CON had access to the same exercise equipment but received no specific advice on their exercise-training regime. Participants completed a graded exercise test, using an arm crank ergometer at pre- and post-training to determine peak oxygen uptake, with RPE_P and RPE_C recorded every minute throughout tests. Sixteen weeks training did not improve peak oxygen uptake. RPE decreased post-training at 50% (p = 0.02) and 70% peak oxygen uptake (p = 0.03), though there was no effect of group at either intensity (p = 0.54, 0.42, respectively). At 70% peak oxygen uptake, RPE_P was greater than RPE_C (4.2 ± 1.7 vs 3.4 ± 1.8, p < 0.005). Training with RPE-guidance for 16 weeks had no additional effect on the differentiated RPE responses to moderate-vigorous exercise in adults with SCI. Novelty In adults with SCI, differentiated RPE responses were not different between those who did, and did not, perform 16 weeks of RPE-guided training. This challenges whether familiarisation with RPE is necessary to be an effective regulator of exercise intensity in this population.

Interrater and intrarater reliability of ventilatory thresholds determined in individuals with spinal cord injury

STUDY DESIGN

Cross-sectional.

OBJECTIVES

Individualized training regimes are often based on ventilatory thresholds (VTs). The objectives were to study: (1) whether VTs during arm ergometry could be determined in individuals with spinal cord injury (SCI), (2) the intrarater and interrater reliability of VT determination.

SETTING

University research laboratory.

METHODS

Thirty graded arm crank ergometry exercise tests with 1-min increments of recreationally active individuals (tetraplegia (N = 11), paraplegia (N = 19)) were assessed. Two sports physicians assessed all tests blinded, randomly, in two sessions, for VT1 and VT2, resulting in 240 possible VTs. Power output (PO), heart rate (HR), and oxygen uptake (VO₂) at each VT were compared between sessions or raters using paired samples t-tests, Wilcoxon signed-rank tests, intraclass correlation coefficients (ICC, relative agreement), and Bland-Altman plots (random error, absolute agreement).

RESULTS

Of the 240 VTs, 217 (90%) could be determined. Of the 23 undetermined VTs, 2 (9%) were VT1 and 21 (91%) were VT2; 7 (30%) among individuals with paraplegia, and 16 (70%) among individuals with tetraplegia. For the successfully determined VTs, there were no systematic differences between sessions or raters. Intrarater and interrater ICCs for PO, HR, and VO₂ at each VT were high to very high (0.82-1.00). Random error was small to large within raters, and large between raters.

CONCLUSIONS

For VTs that could be determined, relative agreement was high to very high, absolute agreement varied. For some individuals, often with tetraplegia, VT determination was not possible, thus other methods should be considered to prescribe exercise intensity.

Peak oxygen uptake measured during a perceptually-regulated exercise test is reliable in community-based manual wheelchair users

This study compares test-retest reliability and peak exercise responses from ramp-incremented (RAMP) and maximal perceptually-regulated (PRET_max) exercise tests during arm crank exercise in individuals reliant on manual wheelchair propulsion (MWP). Ten untrained participants completed four trials over 2-weeks (two RAMP (0-40 W + 5-10 W · min^-1) trials and two PRET_max. PRET_max consisted of five, 2-min stages performed at Ratings of Perceived Exertion (RPE) 11, 13, 15, 17 and 20). Participants freely changed the power output to match the required RPE. Gas exchange variables, heart rate, power output, RPE and affect were determined throughout trials. The V̇O_2peak from RAMP (14.8 ± 5.5 ml · kg^-1 · min^-1) and PRET_max (13.9 ± 5.2 ml · kg^-1 · min^-1) trials were not different (P = 0.08). Measurement error was 1.7 and 2.2 ml · kg^-1 · min^-1 and coefficient of variation 5.9% and 8.1% for measuring V̇O_2peak from RAMP and PRET_max, respectively. Affect was more positive at RPE 13 (P = 0.02), 15 (P = 0.01) and 17 (P = 0.01) during PRET_max. Findings suggest that PRET_max can be used to measure V̇O_2peak in participants reliant on MWP and leads to a more positive affective response compared to RAMP.

Cardiovascular disease risk marker responses to breaking up prolonged sedentary time in individuals with paraplegia: the Spinal Cord Injury Move More (SCIMM) randomised crossover laboratory trial protocol

INTRODUCTION

Sedentary behaviour is a distinct risk factor for cardiovascular disease (CVD) and could partly explain the increased prevalence of CVD in people with spinal cord injury (SCI). Interrupting prolonged sitting periods with regular short bouts of walking acutely suppresses postprandial glucose and lipids in able-bodied individuals. However, the acute CVD risk marker response to breaking up prolonged sedentary time in people with SCI has not been investigated.

METHODS AND ANALYSIS

A randomised two-condition laboratory crossover trial will compare: (1) breaking up prolonged sedentary time with 2 min moderate-intensity arm-crank activity every 20 min, with (2) uninterrupted prolonged sedentary time (control) in people with SCI. Outcomes will include acute effects on postprandial glucose, insulin, lipids and blood pressure. Blood samples will be collected and blood pressure measured at regular intervals during each 5½-hour condition.

ETHICS AND DISSEMINATION

This study was approved by the Cambridge South National Health Service Research Ethics Committee. This research will help determine if breaking up prolonged sedentary time could be effective in lowering CVD risk in people with SCI. The findings of the research will be published in a peer-reviewed journal and disseminated to relevant user groups.

TRIAL REGISTRATION NUMBER

ISRCTN51868437; Pre-results.