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Shin S, Simpkins C, Ahn J, Yang F. Impact of standing perturbation intensities on fall and stability outcomes in healthy young adults. J Biomech 2024; 168:112123. [PMID: 38696984 DOI: 10.1016/j.jbiomech.2024.112123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 03/14/2024] [Accepted: 04/24/2024] [Indexed: 05/04/2024]
Abstract
Motorized treadmills have been extensively used in investigating reactive balance control and developing perturbation-based interventions for fall prevention. However, the relationship between perturbation intensity and its outcome has not been quantified. The primary purpose of this study was to quantitatively analyze how the treadmill belt's peak velocity affects the perturbation outcome and other metrics related to the reactive balance in young adults while the total belt displacement is controlled at 0.36 m. Thirty-one healthy young adults were randomly assigned into three groups with different peak belt speeds: low (0.9 m/s), medium (1.2 m/s), and high (1.8 m/s). Protected by a safety harness, participants were exposed to a forward support surface translation while standing at an unexpected timing on an ActiveStep treadmill. The primary (perturbation outcome: fall vs. recovery) and secondary (dynamic stability, hip descent, belt distance at liftoff, and recovery step latency) outcome measures were compared among groups. Results revealed that a higher perturbation intensity is correlated with a greater faller rate (p < 0.001). Compared to the low- and medium-intensity groups, the high-intensity group was less stable (p < 0.001) with a larger hip descent (p < 0.001) and a longer belt distance (p < 0.001) at the recovery step liftoff. The results suggest that the increased perturbation intensity raises the risk of falling with larger instability and poorer reactive performance after a support surface translation-induced perturbation in healthy young adults. The findings could furnish preliminary guidance for us to design and select the optimal perturbation intensity that can maximize the effects of perturbation-based training protocols.
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Affiliation(s)
- Sangwon Shin
- Department of Biomechanics, University of Nebraska at Omaha, Omaha, NE 68182, USA
| | - Caroline Simpkins
- Department of Kinesiology and Health, Georgia State University, Atlanta, GA 30303, USA
| | - Jiyun Ahn
- Department of Kinesiology and Health, Georgia State University, Atlanta, GA 30303, USA
| | - Feng Yang
- Department of Kinesiology and Health, Georgia State University, Atlanta, GA 30303, USA.
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Hiraoka K, Kodama K, Tani E, Tatsumi M, Tomoi T. Observing finger movement influences the stimulus-response process of the subsequent non-aiming finger movement. Somatosens Mot Res 2024; 41:56-62. [PMID: 36730968 DOI: 10.1080/08990220.2023.2173166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 01/23/2023] [Indexed: 02/04/2023]
Abstract
AIM The present study investigated whether observing the finger movement influences the stimulus-response process of the subsequent non-aiming finger movement. METHODS Participants directed their eyes to the finger. Three auditory cues with 3 s intervals were provided in each trial. The participants abducted and adducted the index finger in response to the second and third cues; the first response was considered to be the previous response and the second response was considered to be the subsequent response. The time taken for the stimulus-response process was measured via reaction time. Vision was allowed from 0 to 1 s after the start cue of the previous response, after the cue of the subsequent response, or after the cues of the previous and subsequent responses. RESULTS Online visual information of the stationary finger accelerated the stimulus-response process of the non-aiming finger movement. The acceleration of the stimulus-response process induced by online visual information of the stationary finger was cancelled out by the previous response information, but this cancellation is itself then eliminated by the visual information from the previous response. The visual information from the previous response decelerated the stimulus-response process of the subsequent non-aiming movement, but this deceleration was then itself cancelled out by visual information of the stationary finger immediately before the subsequent non-aiming movement. CONCLUSION Taken together, information regarding the previous response functions as noise interfering with the processes contributing to the subsequent non-aiming movement.
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Affiliation(s)
- Koichi Hiraoka
- Department of Rehabilitation Science, School of Medicine, Osaka Metropolitan University, Habikino City, Japan
| | - Kohei Kodama
- College of Health and Human Sciences, Osaka Prefecture University, Habikino City, Japan
| | - Erika Tani
- College of Health and Human Sciences, Osaka Prefecture University, Habikino City, Japan
| | - Moe Tatsumi
- College of Health and Human Sciences, Osaka Prefecture University, Habikino City, Japan
| | - Takuya Tomoi
- College of Health and Human Sciences, Osaka Prefecture University, Habikino City, Japan
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Pinto AP, Lemos SL, de Almeida Fagundes A, das Neves MF, Lopes-Martins RÁB, Lima FPS, Lima MO. Transcranial photobiomodulation therapy associated with cardiorespiratory rehabilitation in spastic subjects. Lasers Med Sci 2023; 38:249. [PMID: 37910318 DOI: 10.1007/s10103-023-03922-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 10/24/2023] [Indexed: 11/03/2023]
Abstract
The objective of this study was to evaluate the effects of cardiorespiratory rehabilitation (CR) and transcranial photobiomodulation (tPBM) on exercise tolerance (ET), heart rate variability (HRV), and peripheral muscle activity in individuals with spasticity. Fifteen participants with spasticity were randomly assigned to two groups: the tPBM group (tPBMG) consisted of eight volunteers who underwent tPBM (on mode) and CR, while the control group (CG) consisted of seven volunteers who underwent simulated tPBM (off mode) and CR. The CR program included 12 weeks of treatment, twice a week for one hour, involving aerobic exercises and lower limb strengthening. For tPBM, a cluster with three lasers (λ = 680 nm, 808 nm), with a power of 100 mW/laser and energy of 36 J, applied to the F7, F8, and Fpz points. The following parameters were evaluated after 8 and 12 weeks: ET, HRV, and surface electromyography (EMG) of the rectus femoris muscle during orthostasis (ORT), isometric squatting (ISOM), and isotonic squatting (ISOT). Both groups showed a 40% increase in ET for the CG and a 30% increase for the tPBMG. The CG had more pronounced parasympathetic modulation alterations during post-exercise effort and recovery compared to the tPBMG. The EMG results showed that the tPBMG exhibited progressive improvement in muscle activity during ISOM and ISOT, as well as a decrease in the interlimb difference. In conclusion, both CR and tPBMG demonstrated improvements in ET. However, tPBMG specifically showed promising effects on HRV modulation and peripheral muscle electrical activity, providing additional benefits compared to CR alone.
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Affiliation(s)
- Ana Paula Pinto
- Sensorimotor Rehabilitation Engineering Laboratory, Research and Development Institute, Paraiba Valley University - UNIVAP, Av. Shishima Hifumi, São José Dos Campos, São Paulo, 2911, Brazil.
| | - Sérgio Luiz Lemos
- Sensorimotor Rehabilitation Engineering Laboratory, Research and Development Institute, Paraiba Valley University - UNIVAP, Av. Shishima Hifumi, São José Dos Campos, São Paulo, 2911, Brazil
| | - Alessandra de Almeida Fagundes
- Sensorimotor Rehabilitation Engineering Laboratory, Research and Development Institute, Paraiba Valley University - UNIVAP, Av. Shishima Hifumi, São José Dos Campos, São Paulo, 2911, Brazil
| | - Marcele Florêncio das Neves
- Sensorimotor Rehabilitation Engineering Laboratory, Research and Development Institute, Paraiba Valley University - UNIVAP, Av. Shishima Hifumi, São José Dos Campos, São Paulo, 2911, Brazil
| | - Rodrigo Álvaro Brandão Lopes-Martins
- Post-Graduate Program in Human Movement and Rehabilitation, Research Group in Biophotonics and Experimental Therapeutics in Health and Esthetics, Universidade Evangélica de Goiás - UniEVANGÉLICA, Anápolis, Goiás, Brazil
| | - Fernanda Pupio Silva Lima
- Sensorimotor Rehabilitation Engineering Laboratory, Research and Development Institute, Paraiba Valley University - UNIVAP, Av. Shishima Hifumi, São José Dos Campos, São Paulo, 2911, Brazil
| | - Mário Oliveira Lima
- Sensorimotor Rehabilitation Engineering Laboratory, Research and Development Institute, Paraiba Valley University - UNIVAP, Av. Shishima Hifumi, São José Dos Campos, São Paulo, 2911, Brazil
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Sung PS, Park MS. Delayed response in rectus abdominis muscle following a step perturbation in subjects with and without recurrent low back pain. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2023; 32:1842-1849. [PMID: 36939887 DOI: 10.1007/s00586-023-07639-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 02/17/2023] [Accepted: 03/05/2023] [Indexed: 03/21/2023]
Abstract
BACKGROUND Delayed trunk and lower limb muscle activation is associated with balance loss and fall injuries in subjects with recurrent low back pain (LBP). PURPOSE This study was conducted to compare differences in the onset of muscle contractions of the trunk and lower limb muscles following a treadmill-induced step perturbation between subjects with and without LBP. METHODS Eighty-three right limb dominant individuals (43 subjects with LBP and 40 control subjects) were exposed to the perturbation (0.31 m/s velocity for 0.2 m). The electromyography (EMG) reaction times were analyzed during the first step following the perturbation. The EMG electrodes were placed on both sides of the trunk and lower limbs, including the rectus abdominis (RA), erector spinae (ES), tibialis anterior (TA), and gastrocnemius (GA) muscles. RESULTS The group x muscle interaction was statistically significant (F = 9.44, p = 0.003). The TA muscle activation was significantly delayed compared to the RA, ES, and GA. There was a significant interaction on side x muscle (F = 4.14, p = 0.04). The RA muscles were significantly delayed on the non-dominant (t = - 3.35, p = 0.001) and dominant (t = - 2.53, p = 0.01) sides in the LBP group. CONCLUSION The LBP group demonstrated a delayed reaction time on the RA muscles, which indicated poor trunk control relative to the lower limbs. The delayed bilateral RA muscle might indicate possible coordination problems relative to the ES and lower limb muscles, which may lead to potential fall hazards.
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Affiliation(s)
- Paul S Sung
- Department of Physical Therapy, Indiana Wesleyan University, 4201 South Washington Street, Marion, IN, 46953, USA.
| | - Moon Soo Park
- Department of Orthopaedic Surgery, Hallym University Dongtan Sacred Heart Hospital, Medical College of Hallym University, 7, Keunjaebong-Gil, Hwaseong-Si, Gyeonggi-Do, 18450, Republic of Korea
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Figas G, Hadamus A, Błażkiewicz M, Kujawa J. Symmetry of the Neck Muscles' Activity in the Electromyography Signal during Basic Motion Patterns. SENSORS (BASEL, SWITZERLAND) 2023; 23:4170. [PMID: 37112509 PMCID: PMC10140881 DOI: 10.3390/s23084170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 03/01/2023] [Accepted: 04/19/2023] [Indexed: 06/19/2023]
Abstract
The activity of muscles during motion in one direction should be symmetrical when compared to the activity of the contralateral muscles during motion in the opposite direction, while symmetrical movements should result in symmetrical muscle activation. The literature lacks data on the symmetry of neck muscle activation. Therefore, this study aimed to analyse the activity of the upper trapezius (UT) and sternocleidomastoid (SCM) muscles at rest and during basic motions of the neck and to determine the symmetry of the muscle activation. Surface electromyography (sEMG) was collected from UT and SCM bilaterally during rest, maximum voluntary contraction (MVC) and six functional movements from 18 participants. The muscle activity was related to the MVC, and the Symmetry Index was calculated. The muscle activity at rest was 23.74% and 27.88% higher on the left side than on the right side for the UT and SCM, respectively. The highest asymmetries during motion were for the SCM for the right arc movement (116%) and for the UT in the lower arc movement (55%). The lowest asymmetry was recorded for extension-flexion movement for both muscles. It was concluded that this movement can be useful for assessing the symmetry of neck muscles' activation. Further studies are required to verify the above-presented results, determine muscle activation patterns and compare healthy people to patients with neck pain.
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Affiliation(s)
- Gabriela Figas
- Clinic of Medical Rehabilitation, Medical University of Lodz, 90-419 Lodz, Poland; (G.F.); (J.K.)
| | - Anna Hadamus
- Department of Rehabilitation, Faculty of Dental Medicine, Medical University of Warsaw, 02-091 Warsaw, Poland
| | - Michalina Błażkiewicz
- Faculty of Rehabilitation, The Józef Piłsudski University of Physical Education in Warsaw, 00-968 Warsaw, Poland;
| | - Jolanta Kujawa
- Clinic of Medical Rehabilitation, Medical University of Lodz, 90-419 Lodz, Poland; (G.F.); (J.K.)
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Sung PS, Park MS. Ankle reaction times with tray usage following a slip perturbation between subjects with and without chronic low back pain. Gait Posture 2022; 97:196-202. [PMID: 35988435 DOI: 10.1016/j.gaitpost.2022.07.260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 06/29/2022] [Accepted: 07/30/2022] [Indexed: 02/02/2023]
Abstract
BACKGROUND Abnormal stepping strategies have been associated with handheld tasks in subjects with chronic low back pain (LBP). However, the dominant ankle reactions of subjects with LBP remain unclear following a perturbation during handheld tasks. RESEARCH QUESTION Are there differences in the reaction times of the ankle muscles during handheld tasks between subjects with and without LBP following a treadmill-induced slip perturbation? METHODS Thirty-seven right limb dominant subjects with LBP and 37 subjects without LBP participated in the study. Each subject was introduced to a slip perturbation (1.37 m/sec velocity for 8.22 cm) with and without a handheld tray in random order. Subjects were allowed to recover by stepping forward for a 0.12 s duration while bilateral tibialis anterior (TA) and gastrocnemius (GA) muscle reaction times were measured by electromyography (EMG). RESULTS The EMG results indicated that the groups demonstrated significant interactions on the limb sides and muscles (F = 4.86, p = 0.03). The dominant TA reaction time was significantly faster in the LBP group (t = 2.14, p = 0.03) while holding a tray. SIGNIFICANCE The LBP group demonstrated faster reaction times on the dominant TA muscles during perturbations. Clinicians need to consider dominance-dependent compensatory ankle dorsiflexion strategies in LBP patients to help enhance dynamic balance and control.
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Affiliation(s)
- Paul S Sung
- Doctor of Physical Therapy Program, Indiana Wesleyan University, USA.
| | - Moon Soo Park
- Department of Orthopaedic Surgery, Hallym University Dongtan Sacred Heart Hospital, Medical College of Hallym University, Republic of Korea
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Impact of pathological conditions on postural reflex latency and adaptability following unpredictable perturbations: A systematic review and meta-analysis. Gait Posture 2022; 95:149-159. [PMID: 35500364 DOI: 10.1016/j.gaitpost.2022.04.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 04/01/2022] [Accepted: 04/15/2022] [Indexed: 02/02/2023]
Abstract
BACKGROUND Pathological conditions can impair responses to postural perturbations and increase risk of falls. RESEARCH QUESTION To what extent are postural reflexes impaired in people with pathological conditions and can exercise interventions shorten postural reflexes? METHODS MEDLINE, EMBASE, Scopus, SportDiscus and Web of Science were systematically searched for articles comparing muscle activation onset latency in people with pathological conditions to healthy controls following unpredictable perturbations including the effect of exercise interventions (registration: CRD42020170861). RESULTS Fifty-three articles were included for systematic review. Significant delays in muscle activity onset following perturbations were evident in people with multiple sclerosis (n = 7, mean difference [MD]: 22 ms, 95% confidence interval [CI]: 11, 33), stroke (n = 10, MD: 34 ms, 95% CI: 19, 49), diabetes (n = 2, MD: 19 ms, 95% CI: 10, 27), HIV (n = 3, MD: 9 ms, 95% CI: 4, 14), incomplete spinal cord injury (n = 2, MD: 57 ms, 95% CI: 33, 80) and back and knee pain (n = 7, MD: 12 ms, 95% CI: 6, 18), but not in people with Parkinson's disease (n = 10) or cerebellar dysfunction (n = 4). Following exercise interventions, the paretic limb of stroke survivors (n = 3) displayed significantly faster muscle activation onset latency compared to pre-exercise (MD: -13 ms, 95% CI: -24, -4), with no significant changes in Parkinson's disease (n = 3). CONCLUSIONS This systematic review demonstrated that postural reflexes are significantly delayed in people with multiple sclerosis (+22 ms), stroke (+34 ms), diabetes (+19 ms), HIV (+9 ms), incomplete spinal cord injury (+57 ms), back and knee pain (+12 ms); pathological conditions characterized by impaired sensation or neural function. In contrast, timing of postural reflexes was not impaired in people with Parkinson's disease and cerebellar dysfunction, confirming the limited involvement of supraspinal structures. The meta-analysis showed exercise interventions can significantly shorten postural reflex latencies in stroke survivors (-14 ms), but more research is needed to confirm this finding and in people with other pathological conditions.
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Chojowski K, Strzelczyk K, Kuszewski M. Assessment of selected muscles reactivity in the lower spinal segment. MEDICAL SCIENCE PULSE 2022. [DOI: 10.5604/01.3001.0015.8246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Background: Lumbar spine pain is now a common affliction. In 90% of cases, the pain is of ambiguous and multicausal etiology, described as non-specific lower back pain (NLBP). Various models of this dysfunction were examined. The most popular model presents the pain as a result of an insult and secondary to changes in tension and lumbar muscles degeneration. There is no unequivocal solution concerning the cause of lumbar spine pain in the literature.
Aim of the study: To examine the differences in muscles reactivity in the lumbar region in cases who suffer from lumbar spine pain in comparison to otherwise healthy controls.
Material and methods: In total, 50 participants (24 men and 26 women) aged 18–45, including 24 people with pain, and 26 without ailments were included in the study. The visual analogue scale was used to measure pain intensity. The participants were assessed to determine the reactivity of the soft tissues of the lumbar part of the body. Selected muscles of this area were examined using a myotonometer, which shows five parameters relevant to viscoelastic tissues.
Results: There were significant differences in the level of the pain (p<0.001), hypokinesia of the left abdominal rectus (p<0.05), asymmetry indicators for the creep parameter of the erector spinalis and abdominal external oblique muscle, and the stiffness of abdominal rectus (p<0.05). No significant differences for the remaining parameters were found.
Conclusions: Tissue reactivity of selected muscles of the lumbar spine shows slight differences because of pain afflictions occurring in this area.
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Affiliation(s)
- Kacper Chojowski
- Students Scientific Association FASCYnaci, J. Kukuczka’s AWF Katowice, Poland
| | - Kamila Strzelczyk
- Students Scientific Association FASCYnaci, J. Kukuczka’s AWF Katowice, Poland
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Oda H, Sawaguchi Y, Kawasaki T, Fukuda S, Hiraoka K. Influence of the Inter-Trial Interval, Movement Observation, and Hand Dominance on the Previous Trial Effect. Front Hum Neurosci 2021; 15:761514. [PMID: 34776910 PMCID: PMC8581631 DOI: 10.3389/fnhum.2021.761514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 10/06/2021] [Indexed: 11/13/2022] Open
Abstract
Previous studies have shown that current movement is influenced by the previous movement, which is known as the previous trial effect. In this study, we investigated the influence of the inter-trial interval, movement observation, and hand dominance on the previous trial effect of the non-target discrete movement. Right-handed healthy humans abducted the index finger in response to a start cue, and this task was repeated with constant inter-trial intervals. The absolute difference in the reaction time (RT) between the previous and current trials increased as the inter-trial interval increased. The absolute difference in RT reflects the reproducibility of the time taken for the motor execution between two consecutive trials. Thus, the finding supported the view that there is a carryover of movement information from one trial to the next, and that the underlying reproducibility of the RT between the two consecutive trials decays over time. This carryover of movement information is presumably conveyed by implicit short-term memory, which also decays within a short period of time. The correlation coefficient of the RT between the previous and current trials decreased with an increase in the inter-trial interval, indicating that the common responsiveness of two consecutive trials weakens over time. The absolute difference was smaller when the response was performed while observing finger movement, indicating that a carryover of the visual information to the next trial enhances the reproducibility of the motor execution process between consecutive trials. Hand dominance did not influence the absolute difference or correlation coefficient, indicating that the central process mediating previous trial effect of hand movement is not greatly lateralized.
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Affiliation(s)
- Hitoshi Oda
- Graduate School of Comprehensive Rehabilitation, Osaka Prefecture University, Habikino, Japan
| | - Yasushi Sawaguchi
- Graduate School of Comprehensive Rehabilitation, Osaka Prefecture University, Habikino, Japan
| | - Taku Kawasaki
- Graduate School of Comprehensive Rehabilitation, Osaka Prefecture University, Habikino, Japan
| | - Shiho Fukuda
- Graduate School of Comprehensive Rehabilitation, Osaka Prefecture University, Habikino, Japan
| | - Koichi Hiraoka
- College of Health and Human Sciences, Osaka Prefecture University, Habikino, Japan
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Common Motor Drive Triggers Response of Prime Movers When Two Fingers Simultaneously Respond to a Cue. Brain Sci 2021; 11:brainsci11060700. [PMID: 34073345 PMCID: PMC8227196 DOI: 10.3390/brainsci11060700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/16/2021] [Accepted: 05/24/2021] [Indexed: 12/05/2022] Open
Abstract
This study investigated whether the motor execution process of one finger movement in response to a start cue is influenced by the participation of another finger movement and whether the process of the finger movement is dependent on the movement direction. The participants performed a simple reaction time (RT) task, the abduction or flexion of one (index or little finger) or two fingers (index and little fingers). The RT of the prime mover for the finger abduction was significantly longer than that for the flexion, indicating that the time taken for the motor execution of the finger response is dependent on the movement direction. The RT of the prime mover was prolonged when the abduction of another finger, whose RT was longer than the flexion, was added. This caused closer RTs between the prime movers for a two-finger response compared with the RTs for a one finger response. The absolute difference in the RT between the index and little finger responses became smaller when two fingers responded together compared with one finger response. Those results are well explained by a view that the common motor drive triggers the prime movers when two fingers move together in response to a start cue.
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