Single-Leg Squat Delicacies—The Position of the Nonstance Limb is an Important Consideration

Context: The single-leg squat task is often used as a rehabilitative exercise or as a screening tool for the functional movement of the lower limb. Objective: To establish the effect of 3 different positions of the nonstance leg on 3-dimensional kinematics, muscle activity, and center of mass displacement during a single-leg squat. Design: Within-subjects, repeated-measures design. Setting: Movement analysis laboratory. Participants: A total of 10 participants, aged 28.2 (4.42) years performed 3 squats to 60° of knee flexion with the nonstance (1) hip at 90° flexion and knee at 90° flexion, (2) hip at 30° flexion with the knee fully extended, or (3) hip in neutral/0° and the knee flexed to 90°. Main Outcome Measures: Trunk, hip, knee and ankle joint angles, and center of mass displacement were recorded with inertial sensors while muscle activity was captured through wireless electromyography. Results: Most trunk flexion (21.38° [18.43°]) occurred with the nonstance hip at 90° and most flexion of the stance hip (23.10° [6.60°]) occurred with the nonstance hip at 0°. Biceps femoris activity in the 90° squat was 40% more than in the 0° squat, whereas rectus femoris activity in the 0° squat was 29% more than in the 90° squat. Conclusion: The position of the nonstance limb should be standardized when the single-leg squat is used for assessment and be adapted to the aim when used in rehabilitation.

Download Full-text

Lack of Effect of Ankle Position During the Nordic Curl on Muscle Activity of the Biceps Femoris and Medial Gastrocnemius

Journal of Sport Rehabilitation ◽

10.1123/jsr.2015-0130 ◽

2017 ◽

Vol 26 (3) ◽

pp. 202-207 ◽

Cited By ~ 1

Author(s):

Paul Comfort ◽

Amy Regan ◽

Lee Herrington ◽

Chris Thomas ◽

John McMahon ◽

...

Keyword(s):

Muscle Activity ◽

Repeated Measures ◽

Biceps Femoris ◽

Medial Gastrocnemius ◽

Maximum Voluntary Isometric Contraction ◽

Hamstring Strain ◽

Repeated Measures Design ◽

Paired Samples ◽

Significant Difference ◽

Male College

Context:Regular performance (~2×/wk) of Nordic curls has been shown to increase hamstring strength and reduce the risk of hamstring strain injury, although no consensus on ankle position has been provided.Objective:To compare the effects of performing Nordic curls, with the ankle in a dorsiflexed (DF) or plantar-flexed (PF) position, on muscle activity of the biceps femoris (BF) and medial gastrocnemius (MG).Participants:15 male college athletes (age 22.6 ± 2.1 y, height 1.78 ± 0.06 m, body mass 88.75 ± 8.95 kg).Design:A repeated-measures design was used, with participants performing 2 sets of 3 repetitions of both variations of Nordic curls, while muscle activity was assessed via surface electromyography (EMG) of the BF and MG. Comparisons of muscle activity were made by examining the normalized EMG data as the percentage of their maximum voluntary isometric contraction.Results:Paired-samples t test revealed no significant difference in normalized muscle activity of the BF (124.5% ± 6.2% vs 128.1 ± 5.0%, P > .05, Cohen d = 0.64, power = .996) or MG (82.1% ± 3.9% vs 83.5 ± 4.8%, P > .05, Cohen d = 0.32, power = .947) during the Nordic curls in a PF or DF position, respectively.Conclusion:Ankle position does not influence muscle activity during the Nordic curl; however, performance of Nordic curls with the ankle in a DF position may be preferential, as this replicates the ankle position during terminal leg swing during running, which tends to be the point at which hamstring strains have been reported.

Download Full-text

Differences of Thigh Muscle Activation During Various Squat Exercise on Stable and Unstable Surfaces

Exercise Science ◽

10.15857/ksep.2021.30.3.387 ◽

2021 ◽

Vol 30 (3) ◽

pp. 387-395

Author(s):

Soojin Kim ◽

Joo-Hyun Lee ◽

Jihye Heo ◽

Eunwook Chang

Keyword(s):

Muscle Activity ◽

Repeated Measures ◽

Muscle Activation ◽

Vastus Lateralis ◽

Rectus Femoris ◽

Biceps Femoris ◽

Quadriceps Muscle ◽

Thigh Muscle ◽

Unstable Surface ◽

Co Activation

PURPOSE: The purpose of this study was to compare thigh muscle activities and muscle co-activation when performing squats, wall squats, and Spanish squats on stable and unstable ground.METHODS: Twenty-two healthy male subjects (age: 22.50±2.70 years, height: 178.72±6.04 cm, mass: 76.50±6.80 kg, body mass index: 24.00±2.10 kg/m2, and Godin activity questionnaire: 56.30±24.10) voluntarily participated in the study. All of the participants performed three different squat exercises on the floor and the BOSU ball with an electromyograph attached to each participant’s quadriceps (rectus femoris, RF; vastus lateralis, VL; and vastus medialis, VM) and hamstrings (biceps femoris, BF; semitendinosus, ST; and semimembranosus, SM). Repeated measures of analysis of variance were utilized to compare muscle activity during the three squats exercises by floor type.RESULTS: RF (p<.001, η2=.689), VL (p<.001, η2=.622), and VM (p=.002, η2=.375) showed significant differences between exercises. Spanish squats yielded greater BF activity than did wall squats (p=.018, η2=.269). ST yielded greater muscle activity with the BOSU ball than on the floor (p=.018, η2=.269). Finally, there was a significant ground exercise interaction effect on the co-activation, showing greater muscle co-activation with Spanish squats on the BOSU ball compared to squats, squats on the BOSU ball, and wall squat on the BOSU ball.CONCLUSIONS: The findings of this study indicate that Spanish squats could be an effective exercise option for the facilitation of RF, VL, VM, and BF muscle activation. In particular, performing Spanish squats on an unstable surface could be useful for patients who need to improve their quadriceps muscle activation.

Download Full-text

Evaluation of lower limb electromyographic activity when using unstable shoes for the first time: A pilot quasi control trial

Prosthetics and Orthotics International ◽

10.1177/0309364612464812 ◽

2012 ◽

Vol 37 (4) ◽

pp. 275-281 ◽

Cited By ~ 9

Author(s):

Helen Branthwaite ◽

Nachiappan Chockalingam ◽

Anand Pandyan ◽

Gaurav Khatri

Keyword(s):

Muscle Activity ◽

Repeated Measures ◽

Rectus Femoris ◽

Biceps Femoris ◽

Medial Gastrocnemius ◽

Heel Strike ◽

Electromyographic Activity ◽

Temporal Parameters ◽

Unstable Shoes ◽

First Time

Background: Unstable shoes, which have recently become popular, claim to provide additional physiological and biomechanical advantages to people who wear them. Alterations in postural stability have been shown when using the shoe after training. However, the immediate effect on muscle activity when walking in unstable shoes for the first time has not been investigated. Objective: To evaluate muscle activity and temporal parameters of gait when wearing Masai Barefoot Technology shoes® for the first time compared to the subject’s own regular trainer shoes. Study Design: A pilot repeated-measures quasi control trial. Method: Electromyographic measurements of lower leg muscles (soleus, medial gastrocnemius, lateral gastrocnemius, tibialis anterior, peroneus longus, rectus femoris, biceps femoris and gluteus medius) were measured in 15 healthy participants using Masai Barefoot Technology shoes and trainer shoes over a 10-m walkway. Muscle activity of the third and sixth steps was used to study the difference in behaviour of the muscles under the two shoe conditions. Temporal parameters were captured with footswitches to highlight heel strike, heel lift and toe off. Paired samples t-test was completed to compare mean muscle activity for Masai Barefoot Technology and trainer shoes. Results: Indicated that the use of Masai Barefoot Technology shoes increased the intensity of the magnitude of muscle activity. While this increase in the activity was not significant across the subjects, there were inter-individual differences in muscle activity. This variance between the participants demonstrates that some subjects do alter muscle behaviour while wearing such shoes. Conclusion: A more rigorous and specific assessment is required when advising patients to purchase the Masai Barefoot Technology shoe. Not all subjects respond positively to using unstable shoes, and the point in time when muscle behaviour can change is variable. Clinical relevance Use of Masai Barefoot Technology shoe in patient management should be monitored closely as the individual muscle changes and the point in time when changes occur vary between subjects, and evaluation of how a subject responds is not yet clear.

Download Full-text

Influence of the Amount of Instability on the Leg Muscle Activity During a Loaded Free Barbell Half-Squat

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17218046 ◽

2020 ◽

Vol 17 (21) ◽

pp. 8046

Author(s):

Bernat Buscà ◽

Joan Aguilera-Castells ◽

Jordi Arboix-Alió ◽

Adrià Miró ◽

Azahara Fort-Vanmeerhaeghe ◽

...

Keyword(s):

Muscle Activity ◽

Repeated Measures ◽

Perceived Exertion ◽

Vastus Lateralis ◽

Biceps Femoris ◽

The Body ◽

Stability Conditions ◽

Vastus Medialis ◽

Centre Of Mass ◽

Repeated Measures Design

This study aimed to understand the acute responses on the muscular activity of primary movers during the execution of a half-squat under different unstable devices. Fourteen male and female high-standard track and field athletes were voluntarily recruited. A repeated measures design was used to establish the differences between muscle activity of the primary movers, the body centre of mass acceleration and the OMNI-Perceived Exertion Scale for Resistance Exercise (OMNI-Res) in a half-squat under four different stability conditions (floor, foam, BOSU-up and BOSU-down). A significant correlation was found between the highest performance limb muscle activity and body centre of mass acceleration for half-squat floor (r = 0.446, p = 0.003), foam (r = 0.322, p = 0.038), BOSU-up (r = 0.500, p = 0.001), and BOSU-down (r = 0.495, p = 0.001) exercises. For the exercise condition, the half-squat BOSU-up and BOSU-down significantly increased the muscle activity compared to half-squat floor (vastus medialis: p = 0.020, d = 0.56; vastus lateralis: p = 0.006, d = 0.75; biceps femoris: p = 0.000–0.006, d = 1.23–1.00) and half-squat foam (vastus medialis: p = 0.005–0.006, d = 0.60–1.00; vastus lateralis: p = 0.014, d = 0.67; biceps femoris: p = 0.002, d = 1.00) activities. This study contributes to improving the understanding of instability training, providing data about the acute muscular responses that an athlete experiences under varied stability conditions. The perturbation offered by the two BOSU conditions was revealed as the most demanding for the sample of athletes, followed by foam and floor executions.

Download Full-text

Comparison of Muscle Activity Using Unstable Devices During a Forward Lunge

Journal of Sport Rehabilitation ◽

10.1123/jsr.2018-0296 ◽

2020 ◽

Vol 29 (4) ◽

pp. 394-399

Author(s):

Lucinda E. Bouillon ◽

Michael Hofener ◽

Andrew O’Donnel ◽

Amanda Milligan ◽

Craig Obrock

Keyword(s):

Muscle Activity ◽

Repeated Measures ◽

Rectus Femoris ◽

Random Order ◽

Biceps Femoris ◽

Lateral Gastrocnemius ◽

Biceps Femoris Muscle ◽

Repeated Measures Analysis ◽

Closed Chain ◽

Femoris Muscle

Context: Unstable devices in various forms are used as therapeutic adjuncts for prevention or following an injury. A slip-over-the-shoe design with inflatable domes (STEPRIGHT® Stability Trainer) was developed to improve balance. It is unknown how this unstable device affects muscle activity during a closed-chain exercise such as the forward lunge. Objective: To compare muscle activity across 3 surfaces (STEPRIGHT®, Both Sides Up [BOSU®] Balance Trainer, and firm) during a forward lunge. Design: Within-subject, repeated measures. Setting: University physical therapy research laboratory. Participants: A total of 20 healthy, recreationally active subjects (23.4 [1.47] y, 172.7 [14.7] cm, 71.6 [16.8] kg). Intervention: Each subject performed 1 set of 10 repetitions of forward lunge exercise in random order with STEPRIGHT®, BOSU®, and firm surface. Main Outcome Measures: Surface electromyography data, normalized to maximum voluntary isometric contractions (%MVIC), was used to assess muscle activity on rectus femoris, vastus medialis oblique (VMO), biceps femoris, lateral gastrocnemius, fibularis longus, and tibialis anterior. Results: The repeated-measures analysis of variance determined that there was a significant effect for surface type. During the descent of the lunge, the STEPRIGHT® elicited higher rectus femoris (33% [27%] MVIC) compared with BOSU® (22% [14%] MVIC) and VMO (44% [15%] MVIC) on STEPRIGHT® compared with firm (38% [11%] MVIC) (P < .05). During the ascent of the lunge, the rectus femoris (38% [27%] MVIC) using STEPRIGHT® was higher than BOSU® (24% [16%] MVIC), and STEPRIGHT® elicited higher VMO (65% [20%] MVIC) versus BOSU® (56% [19%] MVIC) (P ≤ .01). The STEPRIGHT® for fibularis longus was higher (descent: 51% [20%] MVIC, ascent: 52% [22%] MVIC) than BOSU® (descent: 36% [15%] MVIC, ascent: 33% [16%] MVIC) or firm (descent: 33% [12%] MVIC, ascent: 35% [15%] MVIC) (P < .001). Conclusions: Clinicians may choose to use the STEPRIGHT® for strengthening VMO and fibularis longus muscles, as these were over 41% MVIC or any of the 3 surfaces for endurance training (<25% MVIC) for biceps femoris muscle. This information may be helpful in exercise dosage for forward lunges when using STEPRIGHT®, BOSU®, or a firm surface.

Download Full-text

Ankle Muscle Activations during Different Foot-Strike Patterns in Running

Sensors ◽

10.3390/s21103422 ◽

2021 ◽

Vol 21 (10) ◽

pp. 3422

Author(s):

Jian-Zhi Lin ◽

Wen-Yu Chiu ◽

Wei-Hsun Tai ◽

Yu-Xiang Hong ◽

Chung-Yu Chen

Keyword(s):

Muscle Activity ◽

Muscle Activation ◽

Stance Phase ◽

Inertial Sensors ◽

Plantar Flexion ◽

Intraclass Correlation ◽

Biceps Femoris ◽

Ankle Muscle ◽

Foot Strike ◽

Muscle Activations

This study analysed the landing performance and muscle activity of athletes in forefoot strike (FFS) and rearfoot strike (RFS) patterns. Ten male college participants were asked to perform two foot strikes patterns, each at a running speed of 6 km/h. Three inertial sensors and five EMG sensors as well as one 24 G accelerometer were synchronised to acquire joint kinematics parameters as well as muscle activation, respectively. In both the FFS and RFS patterns, according to the intraclass correlation coefficient, excellent reliability was found for landing performance and muscle activation. Paired t tests indicated significantly higher ankle plantar flexion in the FFS pattern. Moreover, biceps femoris (BF) and gastrocnemius medialis (GM) activation increased in the pre-stance phase of the FFS compared with that of RFS. The FFS pattern had significantly decreased tibialis anterior (TA) muscle activity compared with the RFS pattern during the pre-stance phase. The results demonstrated that the ankle strategy focused on controlling the foot strike pattern. The influence of the FFS pattern on muscle activity likely indicates that an athlete can increase both BF and GM muscles activity. Altered landing strategy in cases of FFS pattern may contribute both to the running efficiency and muscle activation of the lower extremity. Therefore, neuromuscular training and education are required to enable activation in dynamic running tasks.

Download Full-text

SINGLE LEG SQUAT COMPENSATIONS ASSOCIATE WITH SOFTBALL PITCHING PATHOMECHANICS IN ADOLESCENT SOFTBALL PITCHERS

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967121s00065 ◽

2021 ◽

Vol 9 (7_suppl3) ◽

pp. 2325967121S0006

Author(s):

Gretchen D. Oliver ◽

Kenzie B. Friesen ◽

Regan E. Shaw ◽

David Shannon ◽

Jeffrey Dugas ◽

...

Keyword(s):

Center Of Mass ◽

Knee Valgus ◽

Trunk Rotation ◽

Lateral Flexion ◽

Trunk Flexion ◽

Backward Elimination ◽

Potential Risk Factors ◽

Single Leg Squat ◽

Tracking Device ◽

The Relationship

Background: Softball pitchers have an eminent propensity for injury due to the high repetition and ballistic nature of the pitch. As such, trunk pathomechanics during pitching have been associated with upper extremity pain. The single leg squat (SLS) is a simple diagnostic tool used to examine LPHC and trunk stability. Research shows a lack of LPHC stability is often associated with altered pitching mechanics consequently increasing pain and injury susceptibility. Hypothesis/Purpose: The purpose of this study was to examine the relationship between trunk compensatory kinematics during the SLS and kinematics during foot contact of the windmill pitch. The authors hypothesized there would be a relationship between SLS compensations and pitch kinematics previously associated with injury. In using a simple clinical assessment such as the SLS, athletes, coaches, parents, and clinicians can identify potential risk factors that may predispose the athlete to injurious movement patterns. Methods: Fifty-five youth and high school softball pitchers (12.6±2.2 years, 160.0±11.0 cm, 60.8±15.5 kg) were recruited to participate. Kinematic data were collected at 100Hz using an electromagnetic tracking device. Participants were asked to complete a SLS on their stride leg (contralateral to their throwing arm), then throw 3 fastballs at maximal effort. Values of trunk flexion, trunk lateral flexion, and trunk rotation at peak depth of the SLS were used as the dependent variables in three separate backward elimination regression analyses. Independent variables examined at foot contact of the pitch included: trunk flexion, trunk lateral flexion, trunk rotation, center of mass, stride length, and stride knee valgus. Results: The SLS trunk rotation regression, F(1,56) = 4.980, p = .030, revealed trunk flexion significantly predicted SLS trunk rotation (SE = .068, t = 2.232, p = .030) and explained approximately 7% of variance (Adj. R2 = .066). The SLS trunk flexion regression, F(1,56) = 5.755, p = .020, revealed stride knee valgus significantly predicted SLS trunk flexion (SE = .256, t = 2.399, p = .020) and explained approximately 8% of variance (Adj. R2 = .078). Conclusion/Significance: Additional trunk rotation and trunk flexion at peak depth of the SLS indicate increased knee valgus and trunk flexion at foot contact of the pitch, both of which suggest poor LPHC stability, may increase the potential for injury. Athletes, coaches and clinicians should acknowledge the risk of poor LPHC in softball pitching and implement exercises to improve LPHC stability in effort to decrease pitching pathomechanics and associated pain.

Download Full-text

Lower-Extremity Muscle Activity During Aquatic and Land Treadmill Running at the Same Speeds

Journal of Sport Rehabilitation ◽

10.1123/jsr.2013-0003 ◽

2014 ◽

Vol 23 (2) ◽

pp. 107-122 ◽

Cited By ~ 5

Author(s):

W. Matthew Silvers ◽

Eadric Bressel ◽

D. Clark Dickin ◽

Garry Killgore ◽

Dennis G. Dolny

Keyword(s):

Lower Extremity ◽

Outcome Measures ◽

Muscle Activity ◽

Tibialis Anterior ◽

Rectus Femoris ◽

Biceps Femoris ◽

Swing Phase ◽

Treadmill Running ◽

Vastus Medialis ◽

Lower Extremity Muscle

Context:Muscle activation during aquatic treadmill (ATM) running has not been examined, despite similar investigations for other modes of aquatic locomotion and increased interest in ATM running.Objectives:The objectives of this study were to compare normalized (percentage of maximal voluntary contraction; %MVC), absolute duration (aDUR), and total (tACT) lower-extremity muscle activity during land treadmill (TM) and ATM running at the same speeds.Design:Exploratory, quasi-experimental, crossover design.Setting:Athletic training facility.Participants:12 healthy recreational runners (age = 25.8 ± 5 y, height = 178.4 ± 8.2 cm, mass = 71.5 ± 11.5 kg, running experience = 8.2 ± 5.3 y) volunteered for participation.Intervention:All participants performed TM and ATM running at 174.4, 201.2, and 228.0 m/min while surface electromyographic data were collected from the vastus medialis, rectus femoris, gastrocnemius, tibialis anterior, and biceps femoris.Main Outcome Measures:For each muscle, a 2 × 3 repeated-measures ANOVA was used to analyze the main effects and environment–speed interaction (P ≤ .05) of each dependent variable: %MVC, aDUR, and tACT.Results:Compared with TM, ATM elicited significantly reduced %MVC (−44.0%) but increased aDUR (+213.1%) and tACT (+41.9%) in the vastus medialis, increased %MVC (+48.7%) and aDUR (+128.1%) in the rectus femoris during swing phase, reduced %MVC (−26.9%) and tACT (−40.1%) in the gastrocnemius, increased aDUR (+33.1%) and tACT (+35.7%) in the tibialis anterior, and increased aDUR (+41.3%) and tACT (+29.2%) in the biceps femoris. At faster running speeds, there were significant increases in tibialis anterior %MVC (+8.6−15.2%) and tACT (+12.7−17.0%) and rectus femoris %MVC (12.1−26.6%; swing phase).Conclusion:No significant environment–speed interaction effects suggested that observed muscle-activity differences between ATM and TM were due to environmental variation, ie, buoyancy (presumed to decrease %MVC) and drag forces (presumed to increase aDUR and tACT) in the water.

Download Full-text

Kinematic and EMG Comparison Between Variations of Unilateral Squats Under Different Stabilities

Sports Medicine International Open ◽

10.1055/a-1195-1039 ◽

2020 ◽

Vol 4 (02) ◽

pp. E59-E66

Author(s):

Roland van den Tillaar ◽

Stian Larsen

Keyword(s):

Muscle Activity ◽

Rectus Femoris ◽

Gluteus Medius ◽

Biceps Femoris ◽

Peak Force ◽

Erector Spinae ◽

Trunk Muscles ◽

Training Experience ◽

Free Weight ◽

Weight Condition

AbstractThe purpose of the study was to compare kinematics and muscle activity between two variations of unilateral squats under different stability conditions. Twelve male volunteers (age: 23±5 years, mass: 80±17 kg, height: 1.81±0.11 m, strength-training experience: 4.3±1.9 years) performed four repetitions with the same external load (≈4RM). Two variations (with the non-stance leg forwards vs. backwards) were performed in a Smith-machine and free-weight condition. The variables were barbell velocity, lifting time and surface electromyography activity of the lower extremity and trunk muscles during the descending and ascending phase. The main findings were 1) peak force was higher when performing the unilateral squats in the Smith machine; 2) peak ascending barbell velocity increased from repetition 3–4 with free weight; and 3) muscle activity from the rectus femoris, vastus lateral, biceps femoris, gluteus medius, and erector spinae increased with repetitions, whereas gluteus, and medial vastus and shank muscles were affected by the conditions. It was concluded that more peak force could be produced because of increased stability. However, peak barbell velocity increased from repetition to repetition in free-weight unilateral squats, which was probably because the participants grew more comfortable. Furthermore, increased instability causes more gluteus and vastus medial activation and foot variations mainly affected the calf muscles.

Download Full-text

Comparative Kinematic and Electromyographic Assessment of Clinician- and Device-Assisted Sit-to-Stand Transfers in Patients With Stroke

Physical Therapy ◽

10.2522/ptj.20120500 ◽

2013 ◽

Vol 93 (10) ◽

pp. 1331-1341 ◽

Cited By ~ 20

Author(s):

Judith M. Burnfield ◽

Bernadette McCrory ◽

Yu Shu ◽

Thad W. Buster ◽

Adam P. Taylor ◽

...

Keyword(s):

Repeated Measures ◽

Muscle Activation ◽

Joint Movement ◽

Trunk Flexion ◽

Cross Sectional ◽

Ankle Motion ◽

Repeated Measures Design ◽

Sit To Stand ◽

Lower Extremity Muscle ◽

Combat Injuries

Background Workplace injuries from patient handling are prevalent. With the adoption of no-lift policies, sit-to-stand transfer devices have emerged as one tool to combat injuries. However, the therapeutic value associated with sit-to-stand transfers with the use of an assistive apparatus cannot be determined due to a lack of evidence-based data. Objective The aim of this study was to compare clinician-assisted, device-assisted, and the combination of clinician- and device-assisted sit-to-stand transfers in individuals who recently had a stroke. Design This cross-sectional, controlled laboratory study used a repeated-measures design. Methods The duration, joint kinematics, and muscle activity of 4 sit-to-stand transfer conditions were compared for 10 patients with stroke. Each patient performed 4 randomized sit-to-stand transfer conditions: clinician-assisted, device-assisted with no patient effort, device-assisted with the patient’s best effort, and device- and clinician-assisted. Results Device-assisted transfers took nearly twice as long as clinician-assisted transfers. Hip and knee joint movement patterns were similar across all conditions. Forward trunk flexion was lacking and ankle motion was restrained during device-assisted transfers. Encouragement and guidance from the clinician during device-assisted transfers led to increased lower extremity muscle activation levels. Limitations One lifting device and one clinician were evaluated. Clinician effort could not be controlled. Conclusions Lack of forward trunk flexion and restrained ankle movement during device-assisted transfers may dissuade clinicians from selecting this device for use as a dedicated rehabilitation tool. However, with clinician encouragement, muscle activation increased, which suggests that it is possible to safely practice transfers while challenging key leg muscles essential for standing. Future sit-to-stand devices should promote safety for the patient and clinician and encourage a movement pattern that more closely mimics normal sit-to-stand biomechanics.

Download Full-text