Carrying Asymmetric Loads While Walking on a Treadmill Interferes with Lower Limb Coordination

The purpose of this study was to investigate the effect of different load carriage modes on coordinative patterns in the lower extremities during walking. Twenty-five university students walked on a treadmill at their preferred pace under three different load conditions: symmetric load (5% of body mass in messenger bags on each shoulder hanging vertically and against the hips), asymmetric load 1 (10% of body mass in a messenger bag on one shoulder hanging vertically against the ipsilateral hip), and asymmetric load 2 (10% of body mass in a messenger bag on one shoulder with the bag draped across the trunk to the contralateral hip). Altered thigh-shank and shank-foot couplings were found for the loaded side during the stance of gait when comparing the asymmetric 1 and 2 to the symmetric load. In addition, thigh-thigh coupling was changed during gait when comparing the asymmetric load 2 and symmetric load. However, we did not find any significant differences in intralimb and interlimb couplings between the two different asymmetric load conditions. The results suggest potential benefits when carrying symmetrical loads in order to decrease abnormal limb coordination in daily activities. Thus, it may be advisable to distribute load more symmetrically to avoid abnormal gait.

Pitching shoulder passive flexibility: torque-angle analysis for external rotation and internal rotation

In this study, a custom device was developed to analyse the pitching shoulder's external rotation (ER) and internal rotation (IR) passive flexibility. We analysed three novel measures: the resistance onset angle (ROA = angle where the shoulder begins stretching), rotational stiffness, and torque at the end range of motion (ROM). The purpose was to conduct a bilateral analysis to determine if there are significant differences between the throwing and non-throwing shoulder. Participants were 30 upper level pitchers (13 division I, 17 minor league). During testing, pitchers laid supine on a treatment table and the arm was secured to a rotational wheel with the shoulder abducted 90° and elbow flexed 90°. Dependent t-tests revealed significant (p < 0.01) and relatively extreme bilateral differences for all three variables. The throwing shoulder had: increased ER ROA (9°), decreased IR ROA (5.3°), increased ER stiffness (17%), increased IR stiffness (34%), increased ER torque (21%), and increased IR torque (30%). Secondary correlation analysis was completed to determine if the torque-angle variables were good predictors of the end ROM. Stiffness correlations were weak for ER (r = 0.35, p = 0.048) and IR (r = 0.42, p = 0.017) but ROA correlations were strong for ER (r = 0.85, p < 0.001) and IR (r = 0.86, p < 0.001).

Developing reliable measures of the passive torque-angle relationship for shoulder internal and external rotation: Implications for overhead athletics

OBJECTIVES

1) Thoroughly assess shoulder flexibility by establishing the passive torque-angle relationship for internal and external rotation with the arm in an overhead athletics position (abducted 90°) and 2) test the reliability of four passive torque-angle measures.

DESIGN

Reliability study.

SETTING

Data were collected in a university biomechanics laboratory.

PARTICIPANTS

Bilateral shoulder flexibility of 15 male college students (20.7 ± 1.1 y) was evaluated twice in two sessions over 7-10 days.

MAIN OUTCOME MEASURES

For both ER and IR, reliability was assessed bilaterally (intra-session, inter-session, and inter-tester) for the traditional range of motion measure and three novel kinetic measures: torque at end ROM, resistance onset angle, rotational stiffness. This resulted in 48 total assessments.

RESULTS

Thirty-four assessments had good to excellent reliability (ICC ≥ 0.8), 10 had fair reliability (0.7 ≤ ICC < 0.8), and 4 had poor reliability (ICC< 0.7). Three of the four flexibility measures had a good overall ICC score: ROM (0.83), torque at end ROM (0.84), and resistance onset angle (0.81). The fourth, stiffness, had a fair overall reliability score (0.74).

CONCLUSIONS

The passive torque-angle measures should be assimilated into clinical and research settings to determine the relevance to injury, rehabilitation, and performance.

The effect of wheelchair propulsion style on changes in time spent in extreme wrist orientations after a bout of fatiguing propulsion

This study compared how wheelchair propulsion styles affect changes in percentage of time spent in extreme wrist orientations, which have been associated with median nerve injury, after a fatiguing bout of propulsion. Twenty novice, non-disabled adult males learned arcing (ARC) and semicircular (SEMI) propulsion styles and utilised each to perform a wheelchair fatigue protocol. ARC and SEMI did not significantly differ in terms of changes after the fatigue protocol in percentage of time spent in extreme flexion/extension or radial/ulnar deviation at the push phase beginning or end. A pattern was observed, although not significant, of greater increases in percentage of time spent in extreme wrist extension and ulnar deviation during the push phase beginning and ulnar deviation during the push phase end while utilising SEMI relative to ARC. This study evinces that individual differences are greater than observed changes in extreme wrist orientations for both propulsion styles. Practitioner Summary: How wheelchair propulsion styles change with fatigue in terms of extreme wrist orientations was examined. This study evinces that individual differences are greater than observed changes in extreme wrist orientations for both propulsion styles and point towards the need for future research on individual differences utilising propulsion styles.

The Effect of Propulsion Style on Wrist Movement Variability During the Push Phase After a Bout of Fatiguing Propulsion

BACKGROUND

Wheelchair propulsion has been linked to overuse injuries regardless of propulsion style. Many aspects of the arcing (ARC) and semicircular (SEMI) propulsion styles have been compared, but differences in intracycle movement variability, which have been linked to overuse injuries, have not been examined.

OBJECTIVE

To explore how ARC and SEMI affect changes in intracycle wrist movement variability after a fatiguing bout of propulsion.

DESIGN

Repeated measures crossover design.

SETTING

Wheelchair rollers and wheelchair fatigue course in a research laboratory.

PARTICIPANTS

Twenty healthy, nondisabled adult men without previous wheelchair experience.

INTERVENTIONS

Participants learned ARC and SEMI and used each to perform a wheelchair fatigue protocol.

MAIN OUTCOME MEASUREMENTS

Thirty seconds of propulsion on rollers were recorded by motion-capture cameras before and after a fatigue protocol for each propulsion style on 2 testing days. Angular wrist orientations (flexion/extension and radial/ulnar deviation) and linear wrist trajectories (mediolateral direction) were computed, and intracycle movement variability was calculated as standard deviations of the detrended and filtered values during the push phase beginning and end. Paired samples t tests were used to compare ARC and SEMI based on the percent changes from pre- to postfatigue protocol.

RESULTS

Both propulsion styles resulted in increased intracycle wrist movement variability postfatigue, but observed increases did not significantly differ between ARC and SEMI.

CONCLUSIONS

This study evinces that intersubject variability exceeded average changes in intracycle wrist movement variability for both propulsion styles. Neither propulsion style resulting in a greater change in intracycle movement variability may suggest that no single propulsion style is ideal for everyone. The large intersubject variability may indicate that the propulsion style resulting in the smallest increase in intracycle movement variability after a fatiguing bout of propulsion may differ for each person and may help explain why wheelchair users self-select to use different propulsion styles.

Adaptation Strategies of Individuals With Anterior Cruciate Ligament Reconstruction

Background:

Despite the strong implications for rehabilitation design, the capability of individuals with anterior cruciate ligament reconstruction (ACLR) to adapt and store novel gait patterns have not been well studied.

Purpose:

To investigate how reconstructive surgery may affect the ability to adapt and store novel gait patterns in persons with ACLR while walking on a split-belt treadmill.

Study Design:

Controlled laboratory study.

Methods:

Gait adaptation was compared between 20 participants with ACLR and 20 healthy controls during split-belt treadmill walking. Gait adaptation was assessed in slow- and fast-adapting parameters by (1) the magnitude of symmetry during late adaptation and (2) the amount of the asymmetry during de-adaptation.

Results:

Healthy individuals adapted a new walking pattern and stored the new walking pattern equally in both the dominant and nondominant limbs. Conversely, individuals with ACLR displayed impairments in both slow-adapting and fast-adapting derived gait adaptation and significant differences in behavior between the reconstructed and uninjured limb.

Conclusion:

While surgical reconstruction and physical therapy are aimed at improving mechanical stability to the knee, the study data suggest that fundamental features of motor control remain altered. After ACLR, participants display an altered ability to learn and store functional gait patterns.

Repetitive finger movement performance differs among Parkinson's disease, Progressive Supranuclear Palsy, and spinocerebellar ataxia

Background

Differentiating movement disorders is critical for appropriate treatment, prognosis, and for clinical trials. In clinical trials this is especially important as effects can be diluted by inclusion of inappropriately diagnosed participants. In early disease duration phases, disorders often have overlapping clinical features, such as impairments in repetitive finger movement, making diagnosis challenging. The purpose of this pilot study was to examine and compare repetitive finger movement performance in participants diagnosed with idiopathic Parkinson’s disease, Progressive Supranuclear Palsy, and spinocerebellar ataxias.

Methods

Participants completed an unconstrained index finger flexion/extension movement (i.e. finger tap) in time with an incremental acoustic tone. Measures of movement rate, movement amplitude, and coefficient of variation were compared among groups.

Results

Significant differences between groups were revealed for movement rate at faster tone rates. Participants with Parkinson’s disease tended to tap faster than the tone rate while participants with Progressive Supranuclear Palsy and spinocerebellar ataxia tended to tap slower. No significant differences were revealed for movement amplitude, but participants with spinocerebellar ataxia demonstrated greater variance in amplitude than participants with Parkinson’s disease.

Conclusion

Quantitative analysis of repetitive finger movement performance at faster rates may be helpful to differentiate Parkinson’s Disease, Progressive Supranuclear Palsy and spinocerebellar ataxia.

Wheelchair ergonomic hand drive mechanism use improves wrist mechanics associated with carpal tunnel syndrome

Among conventional manual wheelchair (CMW) users, 49% to 63% experience carpal tunnel syndrome (CTS) that is likely induced by large forces transmitted through the wrist and extreme wrist orientations. The ergonomic hand drive mechanism (EHDM) tested in this study has been shown to utilize a more neutral wrist orientation. This study evaluates the use of an EHDM in terms of wrist orientations that may predispose individuals to CTS. Eleven adult full-time CMW users with spinal cord injury participated. Motion data were captured as participants propelled across a flat surface, completing five trials in a CMW and five trials in the same CMW fitted with the EHDM. Average angular wrist orientations were compared between the two propulsion styles. Use of the EHDM resulted in reduced wrist extension and ulnar deviation. The shift to more neutral wrist orientations observed with EHDM use may reduce median nerve compression.

Validation of a cardiorespiratory fitness assessment for firefighters

Currently, a submaximal protocol is used to measure cardiorespiratory fitness in firefighters by estimating their true aerobic capacity (V[Combining Dot Above]O2max); however, this submaximal test has not been cross-validated among firefighters. Thirty firefighters (85% male, 15% female), completed the submaximal protocol and the maximal (Bruce) treadmill protocol on separate occasions. Pearson's correlation analyses between the submaximal and Bruce protocol revealed a significant moderate positive correlation (r = 0.635, p = 0.005). The range of mean V[Combining Dot Above]O2max values and SDs produced from the submaximal and maximal protocols varied greatly (35.4-50.9 vs. 28.6-58.4 ml·kg·min, and SD of 3.91 vs. 7.22, respectively). The submaximal V[Combining Dot Above]O2 test underestimated the true V[Combining Dot Above]O2max in the majority of firefighters (72.4%) and overestimated the true V[Combining Dot Above]O2max in the remainder of firefighters. Participants with a higher body fat percentage were more likely (p = 0.0157) to have an overestimated true V[Combining Dot Above]O2max than those with a lower-body fat percentage. Our results indicate the current submaximal V[Combining Dot Above]O2 test used to measure cardiorespiratory fitness in firefighters is an improvement over previous protocols. However, our findings also show that the accuracy of this submaximal test for predicting the true V[Combining Dot Above]O2max in firefighters is questionable, and may not identify firefighters who possess substandard cardiorespiratory fitness, particularly in those with a higher percentage of body fat. Thus, the results of this study indicate that improvements to the current Fire Service Joint Management, Wellness & Fitness Initiative (WFI) V[Combining Dot Above]O2 assessment is still needed to accurately reflect the true V[Combining Dot Above]O2max of individual firefighters.

Persons with reconstructed ACL exhibit altered knee mechanics during high-speed maneuvers

Anterior cruciate ligament (ACL) injury is a sports trauma that causes long-term disability. The function of the knee during dynamic activities can be severely limited even after successful surgical reconstruction. This study examined the effects of approach velocity during side-step cutting on knee joint mechanics in persons with reconstructed ACL (ACLR). 22 participants (11 with unilateral ACLR, 11 matched-controls) participated. Knee joint mechanics were tested in 3 approach conditions: counter-movement, one-step, and running. Dependent variables, including peak knee flexion, extension, valgus, varus, internal rotation, external rotation angles and corresponding peak joint moments, were assessed during the stance phase of cutting. Two 2×3 ("group" by "approach condition") mixed MANOVA tests were used to examine the effects of ACLR and approach velocity on knee mechanics. ACLR participants exhibited higher knee internal rotator moment (0.22 vs. 0.13 Nm/kg, p=0.003). Inter-group comparisons revealed that the ACLR participants exhibited significantly higher abductor and internal rotator moments only in the running condition (1.86 vs. 1.16 Nm/kg, p=0.018; 0.28 vs. 0.17 Nm/kg, p=0.010, respectively). Our findings suggested that patients with ACLR may be at increased risk of re-injury when participating in high-demand physical activities. Task demand should be considered when prescribing progressive therapeutic interventions to ACLR patients.

Comparison of metabolic cost, performance, and efficiency of propulsion using an ergonomic hand drive mechanism and a conventional manual wheelchair

OBJECTIVE

To compare the metabolic cost (oxygen uptake per unit time [V˙o2 consumption], heart rate, and number of pushes), performance (velocity and distance traveled), and efficiency (oxygen uptake per distance traveled [Vo2 efficiency]) of propulsion using a novel ergonomic hand drive mechanism (EHDM) and a conventional manual wheelchair (CMW).

DESIGN

Repeated-measures crossover design.

SETTING

Semicircular track.

PARTICIPANTS

Adult full-time manual wheelchair users with spinal cord injuries (N=12; mean age ± SD, 38.8±12.4y; mean body mass ± SD, 73.7±13.3kg; mean height ± SD, 173.6±11.1cm) who were medically and functionally stable and at least 6 months postinjury.

INTERVENTION

Participants propelled themselves for 3.5 minutes at a self-selected pace in a CMW and in the same chair fitted with the EHDM.

MAIN OUTCOME MEASURES

Velocity, distance traveled, number of pushes, V˙o2 consumption, Vo2 efficiency, and heart rate were compared by wheelchair condition for the last 30 seconds of each trial using paired t tests (α=.01).

RESULTS

The CMW condition resulted in more distance traveled (33.6±10.8m vs 22.4±7.8m; P=.001), greater velocity (1.12±0.4m/s vs .75±.30m/s; P=.001), and better Vo2 efficiency (.10±.03mL·kg(-1)·m(-1) vs .15±.03mL·kg(-1)·m(-1); P<.001) than the EHDM condition, respectively. No significant differences were found between the 2 conditions for number of pushes (27.5±5.7 vs 25.7±5.4; P=.366), V˙o2 consumption (6.43±1.9mL·kg(-1)·min(-1) vs 6.19±1.7mL·kg(-1)·min(-1); P=.573), or heart rate (100.5±14.5 beats per minute vs 97.4±20.2 beats per minute; P=.42).

CONCLUSIONS

The results demonstrate that metabolic costs did not differ significantly; however, performance and efficiency were sacrificed with the EHDM. Modifications to the EHDM (eg, addition of gearing) could rectify the performance and efficiency decrements while maintaining similar metabolic costs. Although not an ideal technology, the EHDM can be considered as an alternative mode of mobility by wheelchair users and rehabilitation specialists.

Perceptions of wellness and burnout among certified athletic trainers: sex differences

CONTEXT

Athletic trainers are exposed to various stressors, increasing the potential for burnout and decreasing perceived wellness. Burnout and decreased perceived wellness can result from many factors: years of experience, hours per week worked, or decreased levels of physical activity. Another factor that accounts for a portion of the variance is sex differences.

OBJECTIVE

To determine the differences in burnout, physical activity, and perceived wellness scores relating to sex in District 9 of the National Athletic Trainers' Association (NATA).

DESIGN

Cross-sectional study.

SETTING

Web-based questionnaire.

PATIENTS OR OTHER PARTICIPANTS

Athletic trainers who were included in the e-mail directory of NATA District 9 (men = 232, women = 158).

INTERVENTION(S)

A 19-item questionnaire for burnout, a 36-item questionnaire for perceived wellness, and a 16-item activity questionnaire for physical activity and demographics.

MAIN OUTCOME MEASURE(S)

The variables included demographics (hours per week worked, years of experience, sex), Copenhagen Burnout Inventory (CBI; scores range from 0-100, and higher scores represent a higher level of burnout), Perceived Wellness Survey (PWS; scores range from 1-36, and scores close to 29 are considered healthy), and Baecke Physical Activity Questionnaire (BPAQ; scores range from 1-15, and higher scores represent more physical activity).

RESULTS

Of the 1560 members contacted, 390 responded (response rate = 25%), and 59.5% (n = 232) were male. The mean scores were 38.73 ± 16.9 for men and 46.2 ± 17.1 for women for the CBI, 16.68 ± 2.76 for men and 16.41 ± 2.81 for women for the PWS, and 8.42 ± 1.32 for men and 8.77 ± 1.36 for women for the BPAQ. Men and women worked an average of 55.60 ± 26.03 and 47.86 ± 20.57 hours per week, respectively, and had a mean experience of 14.79 ± 9.86 and 8.92 ± 6.51 years, respectively. Women reported a higher level of burnout (t388 = -4.255, P = .001) and greater levels of physical activity (t388 = -2.52, P = .01) than men. Men reported working more hours (t388 = 3.131, P = .002) and having more years of experience (t388 = 6.568, P = .001) than women. Perceived wellness was not different between sexes (t388 = 0.958, P = .34).

CONCLUSIONS

Our results suggest that women experienced moderate to high burnout and men experienced moderate burnout. Interestingly, men reported lower levels of burnout but worked more hours than women. Future researchers should focus on why women experience higher levels of burnout but work fewer hours. These findings may lead to educational interventions that might reduce burnout and increase professional longevity and quality of work.

Age and Parkinson's disease related kinematic alterations during multi-directional gait initiation

Previous literature suggests that older adults and persons with Parkinson's disease (PWP) exhibit impaired performance during gait initiation (GI) and turning while walking. While researchers have identified specific impairments during GI and turning separately in these populations, little is known about when these two tasks occur concurrently. Our objective was to determine how multi-directional GI kinematics are affected by aging and Parkinson's disease. Kinematic data were collected on 12 healthy young adults (HYA), 11 healthy older adults (HOA) and 11 PWP during GI in four conditions: forward, medial 45°, lateral 45°, and lateral 90°. Spatiotemporal characteristics and segmental angles were analyzed using separate 3 (group)×4 (condition) mixed ANOVA. Combined across all the conditions, HOA took a smaller (P=0.009) and slower (P=0.023) first step, and slower second step (P=0.021) compared to HYA. PWP took a slower first step (P=0.009), and longer time to initiate the second step (P=0.017) compared to HOA. Also, PWP had greater head rotation at the start of GI during the medial 45° condition (P=0.043) and reduced overall segmental rotation before toe-off of the second step during the lateral 45° condition (P=0.035), and at heel-strike of first step (P=0.031) and before toe-off of second step during lateral 90° condition (P=0.035). For HOA, their general slowness of movement could be attributed to aging effects. For PWP, rigidity and bradykinesia could impair activities of daily living like multi-directional GI and may be associated with an increased risk of falls.

Discriminating between copers and people with chronic ankle instability

CONTEXT

Differences in various outcome measures have been identified between people who have sprained their ankles but have no residual symptoms (copers) and people with chronic ankle instability (CAI). However, the diagnostic utility of the reported outcome measures has rarely been determined. Identifying outcome measures capable of predicting who is less likely to develop CAI could improve rehabilitation protocols and increase the efficiency of these measures.

OBJECTIVE

To determine the diagnostic utility and cutoff scores of perceptual, mechanical, and sensorimotor outcome measures between copers and people with CAI by using receiver operating characteristic curves.

DESIGN

Case-control study.

SETTING

Sports medicine research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Twenty-four copers (12 men, 12 women; age = 20.8 ± 1.5 years, height = 173 ± 11 cm, mass = 78 ± 27 kg) and 24 people with CAI (12 men, 12 women; age = 21.7 ± 2.8 years, height = 175 ± 13 cm, mass = 71 ± 13 kg) participated.

INTERVENTION(S)

Self-reported disability questionnaires, radiographic images, and a single-legged hop stabilization test.

MAIN OUTCOME MEASURE(S)

Perceptual outcomes included scores on the Foot and Ankle Disability Index (FADI), FADI-Sport, and a self-report questionnaire of ankle function. Mechanically, talar position was quantified by measuring the distance from the anterior tibia to the anterior talus in the sagittal plane. Sensorimotor outcomes were the dynamic postural stability index and directional indices, which were calculated during a single-legged hop stabilization task.

RESULTS

Perceptual outcomes demonstrated diagnostic accuracy (range, 0.79-0.91), with 95% confidence intervals ranging from 0.65 to 1.00. Sensorimotor outcomes also were able to discriminate between copers and people with CAI but with less accuracy (range, 0.69-0.70), with 95% confidence intervals ranging from 0.37 to 0.86. The mechanical outcome demonstrated poor diagnostic accuracy (0.52).

CONCLUSIONS

The greatest diagnostic utility scores were achieved by the self-assessed disability questionnaires, which indicated that perceptual outcomes had the greatest ability to accurately predict people who became copers after their initial injuries. However, the diversity of outcome measures that discriminated between copers and people with CAI indicated that the causal mechanism of CAI is probably multifactorial.

17β-Hydroxyestra-4,9,11-trien-3-one (Trenbolone) preserves bone mineral density in skeletally mature orchiectomized rats without prostate enlargement

Testosterone enanthate (TE) administration attenuates bone loss in orchiectomized (ORX) rats. However, testosterone administration may increase risk for prostate/lower urinary tract related adverse events and polycythemia in humans. Trenbolone enanthate (TREN) is a synthetic testosterone analogue that preserves bone mineral density (BMD) and results in less prostate enlargement than testosterone in young ORX rodents. The purpose of this experiment was to determine if intramuscular TREN administration attenuates bone loss and maintains bone strength, without increasing prostate mass or hemoglobin concentrations in skeletally mature ORX rodents. Forty, 10 month old male F344/Brown Norway rats were randomized into SHAM, ORX, ORX+TE (7.0mg/week), and ORX+TREN (1.0mg/week) groups. Following surgery, animals recovered for 1 week and then received weekly: vehicle, TE, or TREN intramuscularly for 5 weeks. ORX reduced total and trabecular (t) BMD at the distal femoral metaphysis compared with SHAMs, while both TREN and TE completely prevented these reductions. TREN treatment also increased femoral neck strength by 28% compared with ORX animals (p<0.05), while TE did not alter femoral neck strength. In addition, TE nearly doubled prostate mass, compared with SHAMs (p<0.05). Conversely, TREN induced a non-significant 20% reduction in prostate mass compared with SHAMs, ultimately producing a prostate mass that was 64% below that found in ORX+TE animals (p<0.01). Hemoglobin concentrations and levator ani/bulbocavernosus (LABC) muscle mass were elevated in ORX+TE and ORX+TREN animals to a similar degree above both SHAM and ORX conditions (p<0.01). In skeletally mature rodents, both high-dose TE and low-dose TREN completely prevented the ORX-induced loss of tBMD at the distal femoral metaphysis and increased LABC mass. TREN also augmented femoral neck strength and maintained prostate mass at SHAM levels. These findings indicate that TREN may be an advantageous agent for future clinical trials evaluating agents capable of preventing bone loss resulting from androgen deficiency.

Oxygen consumption, oxygen cost, heart rate, and perceived effort during split-belt treadmill walking in young healthy adults

During split-belt treadmill walking the speed of the treadmill under one limb is faster than the belt under the contralateral limb. This unique intervention has shown evidence of acutely improving gait impairments in individuals with neurologic impairment such as stroke and Parkinson's disease. However, oxygen use, heart rate and perceived effort associated with split-belt treadmill walking are unknown and may limit the utility of this locomotor intervention. To better understand the intensity of this new intervention, this study was undertaken to examine the oxygen consumption, oxygen cost, heart rate, and rating of perceived exertion associated with split-belt treadmill walking in young healthy adults. Fifteen participants completed three sessions of treadmill walking: slow speed with belts tied, fast speed with belts tied, and split-belt walking with one leg walking at the fast speed and one leg walking at the slow speed. Oxygen consumption, heart rate, and rating of perceived exertion were collected during each walking condition and oxygen cost was calculated. Results revealed that oxygen consumption, heart rate, and perceived effort associated with split-belt walking were higher than slow treadmill walking, but only oxygen consumption was significantly lower during both split-belt walking than fast treadmill walking. Oxygen cost associated with slow treadmill walking was significantly higher than fast treadmill walking. These findings have implications for using split-belt treadmill walking as a rehabilitation tool as the cost associated with split-belt treadmill walking may not be higher or potentially more detrimental than that associated with previously used treadmill training rehabilitation strategies.