Impact of frailty and sex-related differences on postural control and gait in older adults with Parkinson's Disease

BACKGROUND

Parkinson's Disease (PD), a neurodegenerative condition, affects normal aging and leads to reduced motor abilities. In addition, frailty syndrome can increase vulnerability and risks of undesirable effects such as disease progression, falls, disability, and premature death among individuals with PD.

AIMS

To assess the impact of frailty on balance and gait parameters in older with PD and to determine if sex mediates these measures.

METHODS

Twenty-seven (27) participants (n = 18 men; n = 10 frail) performed 4 balance tasks on a force platform (eyes opened/closed in bipodal/semi-tandem position) while linear center of pressure (COP) parameters were calculated. Participants also performed two different speed walks on a gait analysis system to assess gait parameters.

RESULTS

Significant differences between the frail and non-frail group were observed on postural control (mainly for area of COP p = 0.013/d = 0.47/70 %; sway velocity p = 0.048/d = 0.41/23 %) where frail reported poor balance. No significant sex differences were reported for postural control. Gait analysis was comparable between frail and non-frail, while significant differences between men and women were observed for step length (p = 0.002, d = 0.71), step width (p = 0.001, d = 0.75) and base of support (p = 0.012, d = 0.64) variables.

CONCLUSION

Frail Parkinson's individuals present poorer postural control than non-frail individuals, but comparable gait parameters. Men and women are comparable on postural control but show different gait parameters. These results may have implications in clinical decision-making in rehabilitation for frailty in older adults, men and women with Parkinson's disease when balance and gait are of concern.

Vibration-induced postural reactions: a scoping review on parameters and populations studied

Objective

Mechanical vibration is an effective way for externally activating Ia primary endings of the muscle spindles and skin mechanoreceptors. Despite its popularity in proprioception and postural control studies, there is still no review covering the wide variety of vibration parameters or locations used in studies. The main purpose of this scoping review was thus to give an overview of general vibration parameters and to identify, if available, the rationale for justifying methodological choices concerning vibration parameters.

Methods

Three databases (Pubmed, CINHAL, and SPORTDiscus) were searched from inception to July 2022. Included articles were to focus on the study of muscle spindles and skin mechanoreceptors vibration in humans and assess postural control. Following inclusion, data regarding demographic information, populations, vibration parameters and rationale were extracted and summarized.

Results

One hundred forty-seven articles were included, mostly targeting lower extremities (n = 137) and adults (n = 126). The parameters used varied widely but were most often around 80 Hz, at an amplitude of 1 mm for 10-20 s. Regarding rationales, nearly 50% of the studies did not include any, whereas those including one mainly cited the same two studies, without elaborating specifically on the parameter's choice.

Conclusion

This scoping review provided a comprehensive description of the population recruited and parameters used for vibration protocols in current studies with humans. Despite many studies, there remain important gaps of knowledge that needs to be filled, especially for vibration amplitude and duration parameters in various populations.

Bilateral Idiopathic Carpal Tunnel Syndrome: Clinical-Functional Characterization and Efficacy of Two Combined Postoperative Physiotherapeutic Treatments

OBJECTIVE

To evaluate the efficacy of combined association instrument myofascial mobilization (IASTM) and stretching in patients with idiopathic bilateral carpal tunnel syndrome (CTS) operated on one hand and to analyze the response of the operated (OH) and non-operated (NH) hand according to the sequence of therapies. Research on these parameters has not yet been found in the literature.

METHODS

Randomized controlled crossover study with 43 participants using the objective and subjective outcome variables. Patients were randomly assigned to two groups: starting with stretching followed by IASTM and starting with IASTM followed by stretching. Then patients underwent surgery on the hand with more severe involvement and physical therapy rehabilitation was started 30 days after for a period of 4 weeks. After the 1-week interval the participants who started with stretching were referred to IASTM and vice versa, following the same previous patterns. The outpatient reassessments took place at 3 to 6 months. Crossover ANOVA and effect sizes were used as analysis methods.

RESULTS

Time was the most significant outcome for all variables both during therapies and at 6-month follow-up. Regarding response to the combined therapies between OH and NH, there were differences for both OH and NH, with the greatest impact on NH for the palmar grip and VAS variables. The treatment sequences were significant for pain on the NH and mental SF-12, suggesting that starting with IASTM followed by stretching had a superior outcome for these outcomes.

CONCLUSION

The combination of IASTM with stretching, used in the postoperative period of bilateral idiopathic CTS, proved to be supplementary, with significant results and large effect sizes for most of the outcomes assessed, both during the time of application of the therapies and in the 6-month follow-up for both hands, and may constitute a viable therapeutic alternative for this population.

Distinctive phases and variability of vibration-induced postural reactions highlighted by center of pressure analysis

BACKGROUND

The vibration-induced postural reaction paradigm (VIB-PR) offers a unique way for investigating sensorimotor control mechanisms. Measures of VIB-PR are usually calculated from the whole VIB period, yet recent evidence proposed that distinctive mechanisms are likely at play between the early vs. later phases of the postural reaction.

OBJECTIVES

The present work verified if spatiotemporal analyses of center of pressure (COP) displacements can detect differences between these early/later phases of VIB-PR. Also, we further characterized the intra/inter-individual variability of COP measurements, since the underlying variability of VIB-PR remains largely unexplored.

METHODS

Twenty young volunteers realized two experimental conditions of bipodal stance with eyes closed: (i) bilateral VIB of tibialis anterior (TIB) and (ii) Achilles' (ACH) tendons. Each condition consisted of five trials and lasted 30 s as follows: 10 s baseline, 10 s VIB and 10 s post-VIB. Linear COP variables (antero-posterior (AP) amplitude & velocity) were computed for both VIB and post-VIB periods using the following time-windows: early 2 s, the later 8 s and the whole 10 s duration. Intra- and inter-individual variability were respectively estimated using the standard error of the measurement and the coefficient of variation. Both variability metrics were obtained using five vs. the first three trials.

RESULTS

Significant contrasts were found between time-windows for both VIB and post-VIB periods. COP variables were generally higher during the early 2 s phase compared to the later 8 s phase for both TIB [mean difference between 8 s- 2 s phases: Amplitude AP = -1.11 ± 1.14 cm during VIB and -2.99 ± 1.31 during post-VIB; Velocity AP = -1.17 ± 0.86 cm/s during VIB and -3.13 ± 1.31 cm/s during post-VIB] and ACH tendons [Amplitude AP = -0.37 ± 0.98 cm during VIB and -3.41 ± 1.20 during post-VIB; Velocity AP = -0.31 ± 0.59 cm/s during VIB and -3.89 ± 1.52 cm/s during post-VIB]. Most within- and between-subject variability scores were below 30% and using three instead of five trials had no impact on variability. VIB-PR patterns were quite similar within a same person, but variable behaviors were observed between individuals during the later phase.

CONCLUSION

Our study highlights the relevance of identifying and separately analyzing distinct phases within VIB-PR patterns, as well as characterizing how these patterns vary at the individual level.

Towards the Objective Identification of the Presence of Pain Based on Electroencephalography Signals' Analysis: A Proof-of-Concept

This proof-of-concept study explores the potential of developing objective pain identification based on the analysis of electroencephalography (EEG) signals. Data were collected from participants living with chronic fibromyalgia pain (n = 4) and from healthy volunteers (n = 7) submitted to experimental pain by the application of capsaicin cream (1%) on the right upper trapezius. This data collection was conducted in two parts: (1) baseline measures including pain intensity and EEG signals, with the participant at rest; (2) active measures collected under the execution of a visuo-motor task, including EEG signals and the task performance index. The main measure for the objective identification of the presence of pain was the coefficient of variation of the upper envelope (CVUE) of the EEG signal from left fronto-central (FC5) and left temporal (T7) electrodes, in alpha (8-12 Hz), beta (12-30 Hz) and gamma (30-43 Hz) frequency bands. The task performance index was also calculated. CVUE (%) was compared between groups: those with chronic fibromyalgia pain, healthy volunteers with "No pain" and healthy volunteers with experimentally-induced pain. The identification of the presence of pain was determined by an increased CVUE in beta (CVUE_β) from the EEG signals captured at the left FC5 electrode. More specifically, CVUE_β increased up to 20% in the pain condition at rest. In addition, no correlation was found between CVUE_β and pain intensity or the task performance index. These results support the objective identification of the presence of pain based on the quantification of the coefficient of variation of the upper envelope of the EEG signal.

Physical and Functional Clinical Profile of Older Adults in Specialized Geriatric Rehabilitation Care Services in Saguenay-Québec: A Retrospective Study at La Baie Hospital

Musculoskeletal disorders, cardiovascular and neurological diseases were the most commonly debilitating conditions and risk factors associated with pain, mobility limitations, increased risk of falls and disability. Studies barely address the profile of older adults in care within a specialized geriatric rehabilitation service (SGRS) to provide subsidies for new actions within the public healthcare to reduce falls and improve management in health investments. This study aimed to establish a clinical physical and functional profile of the patients with neuromusculoskeletal and cognitive disorders and fallers in interventions within SGRS. From a retrospective study design, 127 medical records were compiled and analyzed to determine the physical and functional profile of older adults and differences according to sex, age groups and the benefits for local physical therapy intervention. The users were between 76 and 85 years of age, with diverse clinical diagnoses and debilitating conditions and impairments. A higher proportion presented gait and balance impairments and had two or more falls in 12 months. A significant effect for advanced age was observed. Overall, real benefits were reported with intervention for functional improvement, although the absence of a control group. These results have direct implications for a better understanding of a local SGRS and provide subsidies for developing new approaches for the assessment and treatment of older adults with high a risk of falls in order to reduce costs for the public health system.

Immediate Effect of Lumbosacral Orthosis and Abdominal Drawing-In Maneuver on Postural Control in Adults With Nonspecific Chronic Low Back Pain

OBJECTIVE

The purpose of this study was to examine the immediate effects of lumbosacral orthosis and the abdominal drawing-in maneuver on the trunk postural control of adults with chronic low back pain compared with asymptomatic controls during 1-legged and semi-tandem stances.

METHODS

An experimental and comparative study (cross-sectional design) was conducted in a laboratory setting. Twenty adults with chronic low back pain and 20 asymptomatic controls randomly performed 2 postural balance tasks over a force platform, considering 3 experimental conditions: (1) natural posture (baseline-control), (2) lumbosacral orthosis, and (3) abdominal drawing-in maneuver. Linear variables (mean amplitude, ellipse area, and sway velocity) derived from the center of pressure were computed, and 2-way analysis of variance (group × condition) for repeated measures were conducted.

RESULTS

No group × condition interactions (.139 ≤ P ≤.938) were detected in any center of pressure parameters. No condition effect was detected, but a group effect (P = .042) was observed for 1 center of pressure parameter. The chronic low back pain group presented with a lower mean anteroposterior center of pressure amplitude than asymptomatic controls (∆ = 0.31 ± 0.66 cm [95% confidence interval, 0.05-0.56], P = .019) during the semi-tandem stance balance task.

CONCLUSION

Neither lumbosacral orthosis nor the abdominal drawing-in maneuver showed immediate improvement in trunk postural control in any group. Thus, clinicians should not expect immediate benefits or improvements yielded by lumbosacral orthosis or the abdominal drawing-in maneuver when patients with chronic low back pain undergo these interventions.

tDCS Task-Oriented Approach Improves Function in Individuals With Fibromyalgia Pain. A Pilot Study

Fibromyalgia (FM) is a complex pain syndrome accompanied by physical disability and loss of daily life activities. Evidences suggest that modulation of the primary motor cortex (M1) by transcranial direct current stimulation (tDCS) improves functional physical capacity in chronic pain conditions. However, the gain on physical function in people living with FM receiving tDCS is still unclear. This study aimed to evaluate whether the tDCS task-oriented approach improves function and reduces pain in a single cohort of 10 FM. A total of 10 women with FM (60.4 ± 15.37 years old) were enrolled in an intervention including anodal tDCS delivered on M1 (2 mA from a constant stimulator for 20 min); simultaneously they performed a functional task. The anode was placed on the contralateral hemisphere of the dominant hand. Outcome assessments were done before the stimulation, immediately after stimulation and 30 min after the end of tDCS. The same protocol was applied in subsequent sessions. A total of five consecutive days of tDCS were completed. The main outcomes were the number of repetitions achieved and time in active practice to evaluate functional physical task performance such as intensity of the pain (visual analog scale) and level of fatigue (Borg scale). After 5 days of tDCS, the number of repetitions achieved significantly increased by 49% (p = 0.012). No change was observed in active practice time. No increase in pain was observed despite the mobility of the painful parts of the body. These results are encouraging since an increase in pain due to the mobilization of painful body parts could have been observed at the end of the 5th day of the experiment. These results support the use of tDCS in task-based rehabilitation.

The Impact of Pain on Functionality, Postural Control and Fall Risk in Woman Aged 45 to 64 Years Old

BACKGROUND

Ageing in women is associated with chronic degenerative pain leading to a functional decrease and therefore increase fall risk. It is therefore essential to detect early functional decreases in the presence of pain related to osteoarthritis.

OBJECTIVE

This cross-sectional study aimed to assess the impact of pain on functionality, postural control and fall risk in women aged between 45 to 64 years old.

METHODS

Twenty-one (21) women aged 45 to 64 were evaluated by clinical and functional measures such as a pain questionnaire (Lequesne Index), functional tests (Stair Step Test, 5 times sit-to-stand, 6MWD, Timed-up and Go) and postural performance (under force platform). Women were classified into 2 groups from the Lequesne Pain Index (PI): low pain (score ≤ 9) and strong pain (score ≥ 10) for subsequent comparisons on functionality (physical and postural control performance).

RESULTS

A significant impact was observed between the pain index (strong PI) and 3 of the 4 functional tests carried out including Stair Step Test (p = 0.001; g = 1.44), walking distance (p = 0.003; g = 1.31) and Timed-up and Go (p = 0.04; g = -0.93). The group with a strong PI score reported further poor postural control under force platform compared to the weak pain group.

CONCLUSION

Pain and severity based on the PI index negatively modulate physical and postural control performance in women aged 45 to 64 years old.

Evaluation of the effects of different applications of kinesio taping on postural control in healthy women

It has been demonstrated that Kinesio Tape (KT) application has immediate positive effects on balance in healthy individuals, but its mid-term effects have not yet been investigated.

OBJECTIVE

Evaluate the effects of KT on postural control in young women, using four strategies.

METHODS

Forty-eight healthy women aged 18-35 years old were randomly assigned to four groups with different elastic bandages (G1: ankle; G2: hamstrings; G3: lumbar; G4: different taping applications) and their postural control was evaluated using stabilographic parameters obtained on a force platform during right and left unipodal (UNP-R and UNP-L) and semi-tamdem tests at pre-intervention (PRE), immediately after (IME), and 24 and 48 h after the application of bandages.

RESULTS

G1 showed a significantly lower velocity in the antero-posterior direction for the PRE compared to the IME period (p = 0.0204) in the UNP-R task, and the same was observed in the medio-lateral velocity when comparing the results for PRE with IME (p = 0.0340 and p = 0.0244) in the UNP-L task. Regarding the frequency, G2 had a significantly lower mean for the PRE, compared to IME (p < 0.001) in the UNP-R in antero-posterior direction, and in medio-lateral direction in the UNP-R (p = 0.003) and in the UNP-L task (p = 0.020).

CONCLUSIONS

The use of KT changed postural control, mainly considering the velocity and frequency of COP oscillations, and especially immediately after its application.

The Impact of Parkinson's Disease on Postural Control in Older People and How Sex can Mediate These Results: A Systematic Review

INTRODUCTION

Parkinson's disease is most prevalent among elderly people, 65 years and over, and leads to an alteration in motor control associated with postural instability. Current evidence shows that postural control decreases with the aging process. In addition, postural control is more altered in healthy aged men than in women. Until today, few studies have evaluated the combined impact of Parkinson's disease and sex on postural control. This review has allowed to evaluate the impact of Parkinson's disease and sex on postural control measurements in elderly people.

METHODOLOGY

Studies have been selected from two main databases: PubMed and EBSCO using the keywords "Parkinson", "postural control OR balance" and "sex". Articles related to the evaluation of postural control, including men and women with Parkinson's aged over 65 years old, regardless of stage, were included (n = 179). Articles were excluded if not written in French or English or not presenting original content.

RESULTS

Ten (10) studies out of 179 that fulfilled inclusion and exclusion criteria were reported in the final analysis, which cumulates a total of 944 individuals with Parkinson's (410 women). In general, results show greater postural instability among people with Parkinson's compared to healthy subjects, and this according to different objective measurements using stabilographic parameters from force platforms. Only two studies out of ten evaluated postural control while briefly considering distinctions between sex, but without showing a significant difference between men and women with Parkinson's. Parkinson's severity, length of time of Parkinson's disease and cognitive state of the person are the three variables with a negative impact on postural control.

CONCLUSION

Older people with Parkinson's disease have greater postural instability. Sex does not seem to influence the postural control of elderly people with Parkinson's, although more studies are necessary.

Vibration of the Whole Foot Soles Surface Using an Inexpensive Portable Device to Investigate Age-Related Alterations of Postural Control

Background: Standing on a foam surface is used to investigate how aging affect the ability to keep balance when somatosensory inputs from feet soles become unreliable. However, since standing on foam also affects the efficacy of postural adjustments, the respective contributions of sensory and motor components are impossible to separate. This study tested the hypothesis that these components can be untangled by comparing changes of center of pressure (CoP) parameters induced by standing on a foam pad vs. a novel vibration (VIB) platform developed by our team and targeting feet soles’ mechanoreceptors.

Methods: Bipedal postural control of young (n = 20) and healthy elders (n = 20) was assessed while standing barefoot on a force platform through 3 randomized conditions: (1) Baseline (BL); (2) VIB; and (3) Foam. CoP Amplitude and Velocity in the antero-posterior/medio-lateral (AP/ML) directions and COP Surface were compared between conditions and groups.

Findings: Both VIB and Foam increased CoP parameters compared to BL, but Foam had a significantly greater impact than VIB for both groups. Young and Old participants significantly differed for all three Conditions. However, when correcting for BL levels of postural performance, VIB-related increase of COP parameters was no longer different between groups, conversely to Foam.

Interpretation: Although both VIB and Foam highlighted age-related differences of postural control, their combined use revealed that “motor” and “sensory” components are differently affected by aging, the latter being relatively unaltered, at least in healthy/active elders. The combined used of these methods could provide relevant knowledge to better understand and manage postural impairments in the aging population.

The immediate effect of two lumbar stabilization methods on postural control parameters and their reliability during two balance tasks

Background: Lumbosacral orthosis (LSO) and/or the isolated contraction of the transversus abdominis muscle by the abdominal drawing-in maneuver (ADIM) can increase lumbar stiffness, consequently influencing postural control. The purpose of this study was to compare the effects of LSO and ADIM on postural control during two balance tasks and determine their reliability.Methods: Twenty participants (50% men) randomly performed three experimental conditions: 1) without lumbar stabilization, 2) with LSO), and 3) with ADIM. Each experimental condition was tested in two postural tasks: semi-tandem and one-legged stance on a force platform for 30 seconds, while the Center of pressure postural (COP) parameters were computed.Results: The two methods of lumbar stabilization were comparable and did not significantly reduce the COP values across time, even though a few individuals presented a change in their COP data above the levels of measurement errors. The reliability of these measurements was generally acceptable and sometimes excellent (≥ 0.90 and ≤10% error measurement).Conclusions: Both LSO and isolated contraction of the transversus abdominis muscle by ADIM do not change postural control in one-legged stance and in semi-tandem tasks. These results have implications for use or not these methods for postural control on a rehabilitation perspective.

Posturographic Analysis in the Elderly with and without sensorineural Hearing Loss

Introduction  Sensorineural hearing loss (SNHL) is a serious public health problem. Some evidence suggests a significant relationship between SNHL and balance disorders. The inability to maintain balance associated with SNHL while standing further increases the risk of falls among older people. Objective  To investigate the association between SNHL on the postural balance in elderly individuals of both genders. Methods  The sample consisted of 247 (166 women) physically independent elderly individuals, (mean age = 68.4 ± 6.0). The instruments used were the anamnesis and the pure tone audiometry for hearing loss, and for balance a force platform based in measures of center of pressure area and of sway velocity in the anteroposterior and mediolateral directions. Results  Presence of hearing loss (HL) was observed in 68% of the participants. We observed a significant association between SNHL and characteristics of balance between the groups with and without HL for center of pressure (COP) area ( p  = 0.010), anteroposterior velocity ( p  = 0.001) and mediolateral velocity ( p  = 0.020). There was a significant difference between the gender groups for center of pressure area ( p  = 0.004), anteroposterior velocity ( p  = 0.001) and mediolateral velocity ( p  = 0.001) with better performance in the female group. Amongst men, there was a difference between the ones with HL and those without it, for COP area ( p  = 0.049). Conclusion  In the present study, elderly individuals with SNHL exhibited more instability on the postural balance, and elderly men presented worse results in the test.

Evaluation isometric and isokinetic of trunk flexor and extensor muscles with isokinetic dynamometer: A systematic review

OBJECTIVE

To systematically review the literature analyzing the reliability and characteristics of the protocols of isokinetic and isometric evaluation of the trunk flexor and extensor muscles with isokinetic dynamometer.

METHODS

This is a systematic review using PubMed, CENTRAL, LILACS, PEDro and SCOPUS databases, searching the oldest records up to December 2019. The risk of bias, the methodological quality and the level of evidence were evaluated using the COSMIN checklist.

RESULTS

Fourteen articles have met the criteria and have been included in this study. All the articles performed an isometric or isokinetic evaluation of the trunk muscles with the isokinetic dynamometer and presented an analysis of the protocol's reliability using the intraclass correlation coefficient. Five articles had excellent reliability (0.93-0.98). Most of the studies presented doubtful and inconsistent psychometric values for reliability, because they used a short period between tests. The level of evidence to the fourteen selected articles for reliability was moderate.

CONCLUSIONS

Although the studies present limitations in methodological quality, it was possible to identify highly reliable patterns in the parameters employed and to present recommendations for the assessment of trunk flexor and extensor muscles in the isokinetic dynamometer, both for assessment in the sitting position and orthostatic.

Effects of lumbar stabilization and muscular stretching on pain, disabilities, postural control and muscle activation in pregnant woman with low back pain

BACKGROUND

Low back pain is common during pregnancy. Lumbar stabilization and stretching exercises are recommended to treat low back pain in the general population. However, few studies have applied the effects of these two interventions in pregnant women with low back pain.

AIM

To compare the effects of lumbar stabilization and stretching exercises for the treatment of gestational low back pain.

DESIGN

A pilot randomized clinical trial.

SETTING

Laboratory of Functional Evaluation and Human Motor Performance and physical therapy clinics.

POPULATION

Initially, 30 pregnant women with low back pain were recruited, of which 24 met the following inclusion criteria: being between 19-29 weeks of gestation; being in prenatal clinical follow-up; having nonspecific mechanical low back pain started in pregnancy; not participating in specific low back pain treatment in the last 3 months. A total of 20 women completed the study (10 each group).

METHODS

The main outcome measures were clinical (pain by Visual Analogue Scale (VAS) and McGill Pain Questionnaire and disability by Roland Morris Questionnaire), and secondary outcome measures were: postural balance (force platform); muscle activation level of multifidus, iliocostalis lumborum, rectus abdominis and external abdominal oblique (electromyography). The women were randomized into two groups for 6 weeks of intervention twice a week for a 50-minute treatment: 1) lumbar stabilization exercise protocol and 2) stretching exercise protocol.

RESULTS

There was a significant reduction (P=0.03) in pain (1.68 in VAS and 4.81 for McGill questionnaire) for both interventions, but no change in disability score. In addition, both interventions were comparable for a significant improvement in postural stability (in mean d=0.77) for the velocity sway parameter, and significantly increased activation (P>0.05) of the external abdominal oblique muscle after intervention.

CONCLUSIONS

Both modalities (lumbar stabilization and stretching) were efficient for pain reduction, improving balance and increasing one trunk activity muscle after 6 weeks of intervention in pregnant women with low back pain.

CLINICAL REHABILITATION IMPACT

The present study has implications, especially for clinical decision-making with regard to therapy choice in pregnant women with LBP to reduce pain and improve trunk function as measured through balance performance.

Effects of land- and water-based exercise programmes on postural balance in individuals with COPD: additional results from a randomised clinical trial

OBJECTIVE

To investigate the effects of water-based exercise training on postural balance in individuals with chronic obstructive pulmonary disease (COPD), and compare the effects of two similar protocols of land- and water-based exercise programmes on postural balance in this population.

DESIGN

Randomised clinical trial.

SETTING

University-based, outpatient, physical therapy clinic.

SUBJECTS

Fifty individuals with COPD.

INTERVENTIONS

Participants were assigned at random to the land group (LG; n=27) or the water group (WG; n=23), and underwent high-intensity endurance and strength training three times per week for 3months.

MAIN OUTCOME MEASURES

Functional balance was assessed by the timed up and go test (TUG), and static balance was assessed with a force platform in the following conditions: standing with feet hip-width apart and eyes open; standing with feet hip-width apart and eyes closed; standing on a short base; and one-legged stance.

RESULTS

Seventeen subjects completed the intervention in the LG {nine males, mean age 64 [standard deviation (SD) 8] years, mean forced expiratory volume in 1 second (FEV₁) 48 (SD 17) %predicted} compared with 14 subjects in the WG [nine males, mean age 65 (SD 8) years, FEV₁ 51 (SD 15) %predicted]. Water-based exercise training had a positive effect on functional balance [TUG: mean difference -1.17 (-1.93 to -0.41 95% confidence interval) seconds; P=0.006], whereas static balance remained unaltered for both groups. There was no between-group difference in postural balance after exercise training; however, a higher proportion of participants who had a clinically relevant improvement in the TUG were in the WG (LG 35%, WG 64%; P<0.001).

CONCLUSION

Functional balance improved after 3months of high-intensity exercise training performed in water. Despite the environment, non-specific training seems to be insufficient to improve static balance.

CLINICAL TRIAL REGISTRATION NUMBER

clinicalTrials.gov NCT01691131.

Time course and variability of tendinous vibration-induced postural reactions in forward and backward directions

Mechanical vibration of tendons induces large postural reactions (PR-VIB) but little is known about how these reactions vary within and between subjects. We investigated the intra- and inter-individual variability of PR-VIB and determined the reliability of center of pressure (COP) measures. Bipodal postural control (eyes closed) of 30 healthy adults were evaluated using a force platform under 02 conditions: bilateral VIB of the tibialis anterior (TA) and Achilles tendons (ACH-T) at 80 Hz. Each condition consisted of 03 trials of 30 s duration (Baseline: 10 s; VIB: 10 s; POST-VIB: 10 s). The Amplitude and Velocity of the COP in the antero-posterior/medio-lateral (AP/ML) directions were recorded and analyzed according to 5 time-windows incremented every 2 s of vibration (i.e. the first 2 s; 4 s; 6 s; 8 s & 10 s), whereas the COP position/AP was monitored every 0.5 s. All postural parameters increased significantly during TA and ACH-T vibration compared to the Baseline. The reliability of the COP measures showed good ICC scores (0.40-0.84) and measurement errors that varied depending on the duration of VIB time-windows. The COP position/AP reveals a lower intra- and inter-subject variability of PR-VIB in the first 2 s of VIB. The metrological characteristics of PR-VIB should be investigated further to guide their future use by clinicians and researchers.

Combining transcutaneous electrical nerve stimulation with therapeutic exercise to reduce pain in an elderly population: a pilot study

PURPOSE

Chronic pain is a highly prevalent and debilitating condition, and there is a pressing need to find safe, effective and affordable treatments to tackle this public health issue. This pilot study aimed to assess whether therapeutic exercises supplemented by transcutaneous electrical nerve stimulation induces a greater hypoalgesic effect than therapeutic exercises supplemented by sham transcutaneous electrical nerve stimulation, in an elderly population suffering from chronic pain.

MATERIALS AND METHODS

Eighteen elderly participants suffering from chronic pain completed a therapeutic exercise program consisting of 45-min group sessions administered twice a week for 4 weeks. Half of the participants received real transcutaneous electrical nerve stimulation during the exercise sessions, while the others received sham transcutaneous electrical nerve stimulation. Participants completed pain questionnaires (McGill Pain Questionnaire, Brief Pain Inventory, Beck Depression Index) before and after the intervention, and recorded their pain levels on an 11-point numerical rating scale before and after each session (Clinical Trial.Gov ID: NCT02445677).

RESULTS AND CONCLUSION

Our results suggest that supplementing exercise sessions with transcutaneous electrical nerve stimulation does not improve the long-term outcomes of elderly patients suffering from chronic pain, but does induce short-term hypoalgesia during exercise sessions. Our study also offers valuable guidelines for the implementation of a future and adequately powered study looking at this research question.Implications for rehabilitationThe application of transcutaneous electrical nerve stimulation during exercises is well tolerated by elderly individuals suffering from chronic pain.Supplementing exercises with transcutaneous electrical nerve stimulation does not seem to improve general outcome in elderly suffering from chronic pain.Notwithstanding, the addition of transcutaneous electrical nerve stimulation tends to produce a marked hypoalgesic effect during the exercise sessions, an effect that could prompt indirect benefits for pain patients.

How many balance task trials are needed to accurately assess postural control measures in older women?

Taking the average of different trials is recommended for better balance assessment, but few studies have really proven this point under different balance conditions.

OBJECTIVE

To assess the effects of averaging trials of five different balance tasks on postural control measures in older women.

METHODS

A total of 90 older women (means: Age: 68 years; Weight: 67 kg; Height: 1.56 m; Body mass index, 27 kg/m²) participated in this study. The participants completed five balance tasks with three performance trials for each task on a force platform in random order. The participants completed a total of three 30-s trials of tasks with 30 s of rest between trials. Repeated measure ANOVA and coefficient of variation were computed to compare differences for one trial vs. averaging across two or three trials on center of pressure (COP) sway values.

RESULTS

There were no significant differences (P > 0.05) in COP sway values when comparing one vs. the average of two or three trials for all balance tasks. However, the coefficient of variation was higher for three trials (10-40%) than two (6-37%) or one trial (3-23%) for COP parameters.

CONCLUSIONS

Based on reduction of variability, the present study recommends the averaging of a minimum of two trials for balance assessment in older women. The results of the current study have implications for balance assessment in older people in fall prevention programs.

Y balance test: Are we doing it right?

OBJECTIVES

The multifaceted characteristic and task-specificity of postural control clearly reflects the need of knowing which factors could influence the balance measures in order to provide reliable and unbiased information. Therefore, this study aimed to investigate the effects of selected anthropometric characteristics, sex, lower limb's strength and dominance on the Y balance test (YBT).

DESIGN

Descriptive laboratory study.

METHODS

Forty-two young adults performed the YBT. The raw and normalized reach distances values were recorded. ANOVA was used to examine differences between sex and limb dominance, whereas multiple linear regression models were built to identify variables associated with better postural control.

RESULTS

No significant sex differences were observed, except for the normalized anterior direction (p=0.0324). No significant differences between limbs emerged. Regression models significantly explained between 8-49% of the variance. Trunk length, strength, and the interaction between sex with strength were the major predictors of the raw measures. Unexpectedly, lower limb length explained only 0.08% of the raw anterior direction variance. Strength and its interaction with sex were positively associated with normalized measures. Surprisingly, the relative lower limb length variable was negatively associated with the normalized measures. Each % point increase in relative lower limb length was associated with a decrease in normalized performance ranging from 1.73 to 4.91%.

CONCLUSIONS

Anthropometric characteristics, sex and lower limb strength differently influenced the YBT measures, regardless of limb dominance. Consequently, these variables should be controlled to limit the variability for an accurate evaluation of postural balance, especially if different YBT measures are used.

Impact of Lifting of Two Types of Barrels on Postural Control, Trunk Muscle Recruitment, and Kinematic Measures in Manual Workers

The aim of this study was to evaluate the impact of 2 types of beer barrels on postural control, trunk activation, and kinematic measures in adult workers. Twelve (12) males randomly performed 4 tasks on a force platform for 20 s: (1) hold an empty recyclable barrel, (2) hold a full recyclable barrel (30 L), (3) hold an empty steel barrel, and (4) hold a full steel barrel (30 L). Trunk muscular activation, force platform and kinematic measures at the trunk, hip, and knee joints were computed. The full steel barrel produced greater postural oscillation than other conditions. Higher trunk activity was also reported during the full steel barrel task. Significant kinematic changes only in the trunk were observed between the empty steel barrel and the full recyclable barrel tasks. In conclusion, the full steel barrel produced a negative impact on postural control, increasing trunk activity and changing trunk flexion angle in adult workers.

Age- and low back pain-related differences in trunk muscle activation during one-legged stance balance task

BACKGROUND

Postural control declines with age and can be affected by low back pain. Poor balance has been reported in people with chronic low back pain (CLBP), which in turn could be explained by the changes in trunk muscle activation.

RESEARCH QUESTION

Are there differences between younger and older adults with and without chronic low back pain (CLBP) on trunk muscle activity during one-legged stance task?

METHODS

Twenty (20) with, and 20 subjects without nonspecific CLBP participated in the study. Each group was comprised of 10 younger (50% males; mean age: 31 years) and 10 older adults (50% males; mean age: 71 years). Subjects performed 3 × 30-second trials of one-legged stance, with eyes open, on a force platform, while surface electromyography (EMG) measurements were obtained bilaterally on the multifidus at L5, iliocostalis lumborum at L3, rectus abdominis and biceps femoris muscles.EMG amplitude analysis was processed by the Root Mean Square (250 ms window epochs) and normalized by the peak of activation during the balance tasks, to determine the muscular activity of each muscle.

RESULTS

Participants with CLBP presented 15% lower lumbar muscle activation (p <  0.05), and 23% higher co-activation (ratio between rectus adominis by multifidus) than participants without CLBP, regardless of age. Significant differences (p <  0.05) between older and young groups were observed only for lower lumbar muscles (mean 24% lower in older than younger adults) and rectus adominis muscles (mean 17% lower in older than younger adults).

SIGNIFICANCE

CLBP individuals have different trunk muscle activity than those without CLBP, and older adults exhibit lower trunk activation during one-legged stance balance task. The use of the EMG in evaluation of trunk neuromuscular function during one-legged stance may thus be a valuable tool when assessing balance in CLBP and older people.

Effect of body mass index and fat mass on balance force platform measurements during a one-legged stance in older adults

The purpose of this study was to evaluate the impact of body mass index (BMI) and fat mass on balance force platform measurements in older adults. The sample consisted of 257 participants who were stratified into four groups by BMI: low weight, normal weight, pre-obesity and obesity. For fat mass variables, older individuals were classified into low and high-fat mass. All groups investigated performed three trials of one-legged stance balance on a force platform. Center of pressure (COP) domain parameters were computed from the mean across trials. Analysis of variance results revealed no significant interactions for groups and sexes for all COP parameters. Comparable balance results were found for BMI and fat groups for all COP parameters. A statistical effect (P < 0.05) was only reported for sex differences for COP parameters, regardless of BMI and fat mass variables. Overall, women presented better balance than men. In conclusion, BMI and fat mass do not seem to influence the balance of older adults during a one-leg stance task.

Citrulline Malate Does Not Improve Muscle Recovery after Resistance Exercise in Untrained Young Adult Men

The effects of citrulline malate (CM) on muscle recovery from resistance exercise remains unknown. We aimed to determine if citrulline malate supplementation improves muscle recovery after a single session of high-intensity resistance exercise (RE) in untrained young adult men. Nine young adult men (24.0 ± 3.3 years) participated in a double-blind crossover study in which they received 6 g of CM and placebo (PL) on two occasions, separated by a seven-day washout period. Each occasion consisted of a single session of high-intensity RE (0 h) and three subsequent fatigue tests sessions (at 24, 48, and 72 h) to assess the time course of muscle recovery. During the tests sessions, we assessed the following variables: number of maximum repetitions, electromyographic signal (i.e., root mean square (RMS) and median frequency (MF)), muscle soreness and perceived exertion, as well as blood levels of creatine kinase (CK), lactate, insulin, and testosterone:cortisol ratio. CK levels increased at 24 h post-exercise and remained elevate at 48 and 72 h, with no difference between CM and PL conditions. Muscle soreness increased at 24 h post-exercise, which progressively returned to baseline at 72 h in both conditions. Lactate levels increased immediately post-exercise and remained elevated at 24, 48, and 72 h in both conditions. No significant treatment × time interaction was found for all dependents variables (maximum repetitions, perceived exertion, CK, lactate, RMS, MF, and testosterone:cortisol ratio) during the recovery period. In conclusion, our data indicate that CM supplementation (single 6 g dose pre-workout) does not improve the muscle recovery process following a high-intensity RE session in untrained young adult men.

Effects of Holding an External Load on the Standing Balance of Older and Younger Adults With and Without Chronic Low Back Pain

OBJECTIVE

The purpose of this study was to assess the effect of holding an external load on the standing balance of younger and older adults with and without chronic low back pain (CLBP).

METHODS

Twenty participants with and 20 without CLBP participated in the study. Each group contained 10 younger (50% men) and 10 older adults (50% men). Participants were instructed to look straight ahead while standing on a force platform during two 120-second trials with and without holding an external load (10% of body mass). The center of pressure area, mean velocity, and mean frequency in the anteroposterior and mediolateral directions were measured.

RESULTS

Older adults had worse standing balance than younger adults did (P < .001, d = 0.20). There were no significant balance differences between participants with and without CLBP within age groups during standing balance condition. However, holding the external load significantly increased postural instability for both age groups and CLBP status, with mean effect size across center of pressure variables of d = 0.82 for older participants without CLBP and d = 2.65 for younger participants without CLBP. These effects for people with CLBP were d = 1.65 for subgroup of older and d = 1.60 for subgroup of younger participants.

CONCLUSION

Holding an external load of 10% of body mass increased postural instability of both younger and older adults with and without CLBP.

People with chronic low back pain have poorer balance than controls in challenging tasks

PURPOSE

To compare the balance of individuals with and without chronic low back pain during five tasks.

METHOD

The participants were 20 volunteers, 10 with and 10 without nonspecific chronic low back pain, mean age 34 years, 50% females. The participants completed the following balance tasks on a force platform in random order: (1) two-legged stance with eyes open, (2) two-legged stance with eyes closed, (3) semi-tandem with eyes open, (4) semi-tandem with eyes closed and (5) one-legged stance with eyes open. The participants completed three 60-s trials of tasks 1-4, and three 30-s trials of task 5 with 30-s rests between trials. The center of pressure area, velocity and frequency in the antero-posterior and medio-lateral directions were computed during each task, and compared between groups and tasks.

RESULTS

Participants with chronic low back pain presented significantly larger center of pressure area and higher velocity than the healthy controls (p < 0.001). There were significant differences among tasks for all center of pressure variables (p < 0.001). Semi-tandem (tasks 3 and 4) and one-leg stance (task 5) were more sensitive to identify balance impairments in the chronic low back pain group than two-legged stance tasks 1 and 2 (effect size >1.37 vs. effect size <0.64). There were no significant interactions between groups and tasks.

CONCLUSIONS

Individuals with chronic low back pain presented poorer postural control using center of pressure measurements than the healthy controls, mainly during more challenging balance tasks such as semi-tandem and one-legged stance conditions. Implications for Rehabilitation People with chronic low back had poorer balance than those without it. Balance tasks need to be sensitive to capture impairments. Balance assessments during semi-tandem and one-legged stance were the most sensitive tasks to determine postural control deficit in people with chronic low back. Balance assessment should be included during rehabilitation programs for individuals with chronic low back pain for better clinical decision making related to balance re-training as necessary.

Balance versus resistance training on postural control in patients with Parkinson's disease: a randomized controlled trial

BACKGROUND

Evidences have shown that physiotherapy programs may improve the balance of individuals with Parkinson's disease (PD), although it is not clear which specific exercise program is better.

AIM

The aim of this study was to compare the effectiveness of balance versus resistance training on postural control measures in PD patients.

DESIGN

Randomized controlled trial.

SETTING

The study was conducted in a physiotherapy outpatient clinic of a university hospital.

POPULATION

A total of 40 PD participants were randomly divided into two groups: balance training (BT) and resistance training (RT).

METHODS

The BT group focused on balance training, functional independence and gait while the RT group performed resistance exercises emphasizing the lower limbs and trunk, both supervised by trained physiotherapists. Therapy sessions were held twice a week (at 60 minutes), totaling 24 sessions. The primary outcome was evaluated by force platform with center of pressure sway measures in different balance conditions and the secondary outcome was evaluated by Balance Evaluation Systems Test (BESTest) scale to determine the effects of the intervention on postural control.

RESULTS

Significant improvement of postural control (pre vs. post 15.1 vs. 9.6 cm2) was only reported in favor of BT group (d=1.17) for one-legged stand condition on force platform. The standardized mean difference between groups was significantly (P<0.02), with 36% of improvement for BT vs. 0.07% for RT on this condition. Significant improvement (P<0.05) was also observed in favor of BT (in mean 3.2%) for balance gains in some BESTest scores, when compared to RT group (-0.98%).

CONCLUSIONS

Postural control in Parkinson's disease is improved when training by a directional and specific balance program than a resistance training program.

CLINICAL REHABILITATION IMPACT

Balance training is superior to resistance training in regard to improving postural control of individuals with PD. Gold standard instruments (high in cost and difficult to access) were used to assess balance, as well as scales with clinical applicability (low cost, easily acceptable, applicable and valid), which can guide the management of physiotherapists both in their decision-making and in clinical practice.

Mcconnell's patellar taping does not alter knee and hip muscle activation differences during proprioceptive exercises: A randomized placebo-controlled trial in women with patellofemoral pain syndrome

The purpose of this study was to assess the effect of patellar taping on muscle activation of the knee and hip muscles in women with Patellofemoral Pain Syndrome during five proprioceptive exercises. Forty sedentary women with syndrome were randomly allocated in two groups: Patellar Taping (based in McConnell) and Placebo (vertical taping on patella without any stretching of lateral structures of the knee). Volunteers performed five proprioceptive exercises randomly: Swing apparatus, Mini-trampoline, Bosu balance ball, Anteroposterior sway on a rectangular board and Mediolateral sway on a rectangular board. All exercises were performed in one-leg stance position with injured knee at flexion of 30° during 15s. Muscle activation was measured by surface electromyography across Vastus Medialis, Vastus Lateralis and Gluteus medius muscles. Maximal voluntary contraction was performed for both hip and knee muscles in order to normalize electromyography signal relative to maximum effort during the exercises. ANOVA results reported no significant interaction (P>0.05) and no significant differences (P>0.05) between groups and intervention effects in all exercise conditions. Significant differences (P<0.01) were only reported between muscles, where hip presented higher activity than knee muscles. Patellar taping is not better than placebo for changes in the muscular activity of both hip and knee muscles during proprioceptive exercises.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT02322515.

External abdominal oblique muscle ultrasonographic thickness changes is not an appropriate surrogate measure of electromyographic activity during isometric trunk contractions

BACKGROUND

The function of specific abdominal muscles can be assessed using both electromyography (EMG) and ultrasound imaging (USI) thickness measures. However, the relationship between these two measurements is not conclusive during sitting isometric trunk efforts.

OBJECTIVE

This study was conducted to assess the relationship between USI thickness and EMG amplitude measures of the right external oblique (EO) muscle during isometric efforts in the sitting position.

METHOD

Eighteen subjects performed ramp isometric efforts progressing from 0 to 50% of their maximal voluntary contraction (MVC) in three trunk directions on a dynamometer: (1) forward flexion; (2) right lateral flexion; and (3) left axial rotation. USI and surface EMG amplitude measures of the EO muscle were recorded concomitantly and both normalized against rest values and maximal EMG, respectively.

RESULTS

EO muscle was significantly more activated (p < 0.001) during forward flexion (42% on average) and axial rotation (35%) than during lateral flexion (24%). Non-significant (r=0.01; P=0.979) to highly significant (r=0.98; P < 0.0001) and negative and positive Pearson correlations were observed between EMG and EO thickness measures for both flexion and rotation directions.

CONCLUSION

The negative correlations between EMG and USI measures as well as the great variability of these correlations across individuals suggest that USI is not a valid measures of EO muscle activity. USI thickness measures should be interpreted with great caution in research and clinical settings.

Five-week sensory motor training program improves functional performance and postural control in young male soccer players - A blind randomized clinical trial

Sensory motor training programs are used in the rehabilitation and prevention of injuries among soccer players. Inconsistencies are found in the literature regarding the duration of the protocols and the exercises and equipment used.

OBJECTIVE

To evaluate the benefits of a five-week sensory motor training program on the functional performance and postural control of young soccer players.

METHODS

The study sample comprised 22 young male soccer players who were evaluated using: the Figure-of-Eight Test (F8), Side Hop Test (SHT), Star Excursion Balance Test (SEBT), and a force platform. The players were randomly divided into a control group (N = 10), who continued their soccer practice sessions and an intervention group (N = 12), who continued their soccer practice sessions and were also enrolled in a supervised five-week sensory motor training program.

RESULTS

After the five-week training program, the intervention group obtained significant results in the F8, SHT and SEBT, as well as in the following parameters: area of pressure of sway center (COP), mean velocity and mean frequency of COP.

CONCLUSION

The five-week sensory motor training program, carried out with easily available and low cost equipment, was effective at improving functional performance and postural control in young soccer players.

Can functional exercise capacity discriminate older individuals with poor postural control?

AbstractPostural instability can be related to functional limitations as a result of the aging process. This study aimed to compare functional exercise capacity and postural control in older adults. Participants were allocated into three groups according to their functional exercise capacity based on the six minute walking test (6MWT): 1) Low performance group (LP: distance walked ≤ 80% of the predicted value n = 19), 2) Normal performance group (NP: distance walked 81-100% of the predicted value n = 21) and, 3) High performance group (HP: distance walked >100% of the predicted value n = 23). All groups performed three trials of a one-leg stance for 30s on a force platform. LP showed worse postural control in comparison to NP and HP, and significant differences (p < .05) were found between groups for area, velocity antero-posterior of center of pressure and time limit variables during the one-leg stance task. These results have implications for rehabilitation management with regard to exercise, balance assessment and intervention in older adults.

Relationship between foot posture measurements and force platform parameters during two balance tasks in older and younger subjects

[Purpose] The aim of this study was to compare age-related differences in balance and anthropometric posture measurements of the foot and to determine any relationship between them. [Subjects and Methods] Sixty-eight older and 42 younger adults participated in this study. Foot posture was tested for four domains: 1) hallux flexion and extension range of motion using a goniometer, 2) navicular height and 3) length of the foot using a pachymeter, and 4) footprint (width of forefoot, arch index and hallux valgus). Balance was tested under two conditions on a force platform: bipodal in 60-s trials and unipodal in 30-s trials. The sway area of the center of pressure and velocity in the anteroposterior and mediolateral directions were computed. [Results] Older individuals showed significantly poorer balance compared with younger adults under in the unipodal condition (center of pressure area 9.97 vs. 7.72 cm(2)). Older people presented a significantly lower hallux mobility and higher values for width of the forefoot and transverse arch index than younger adults. The correlations between all foot posture and center of pressure parameters varied across groups, from weak to moderate (r -0.01 to -0.46). Low hallux mobility was significantly related to higher center of pressure values in older people. [Conclusion] These results have clinical implications for balance and foot posture assessments.

Older adults present better back endurance than young adults during a dynamic trunk extension exercise

BACKGROUND AND OBJECTIVE

Poor back endurance is a predictor of low back pain. Few studies have investigated back muscle fatigue in older people. The purpose of this study was to compare the back muscle fatigue by endurance time and perceived effort between young and older adults during dynamic exercise.

METHOD

Sixteen older and 16 young adults, all healthy, participated in this study. The subjects performed a fatiguing trunk extension-flexion exercise on a Roman chair until exhaustion. Endurance time and perceived muscle fatigue (Borg CR-10 scale) were used as fatigue criteria.

RESULTS

The older adults were significantly (T<formula>_{(30)}</formula> = -2,073; p = 0.039) more resistant to back muscle fatigue (time in mean 133 ± 52 s) than the young adults (mean 97 ± 27 s). In general, both groups had the same perception of high-level fatigue during the exercise bout (T<formula>_{(29)}</formula> = 1.73; p=0.092).

CONCLUSION

The older adults presented better back endurance than young adults during a dynamic trunk extension exercise. These results have implications for back endurance in the primary prevention of low back pain in both young and older adults.

Age-related differences in time-limit performance and force platform-based balance measures during one-leg stance

Poor posture control has been associated with an increased risk of falls and mobility disability among older adults. This study was conducted to assess the test-retest reliability and sensitivity to group differences regarding the time-limit (TLimit) of one-leg standing and selected balance parameters obtained with a force platform in older and young adults. A secondary purpose was to assess the relationship between TLimit and these balance parameters. Twenty-eight healthy older adults (age: 69±5years) and thirty young adults (age: 21±4years) participated in this study. Two one-leg stance tasks were performed: (1) three trials of 30s maximum and (2) one TLimit trial. The following balance parameters were computed: center of pressure area, RMS sway amplitude, and mean velocity and mean frequency in both the anterio-posterior and medio-lateral directions. All balance parameters obtained with the force platform as well as the TLimit variable were sensitive to differences in balance performance between older and young adults. The test-retest reliability of these measures was found to be acceptable (ICC: 0.40-0.85), with better ICC scores observed for mean velocity and mean frequency in the older group. Pearson correlations coefficients (r) between balance parameters and TLimit ranged from -0.16 to -0.54. These results add to the current literature that can be used in the development of measurement tools for evaluating balance in older and young adults.

Back muscle strength and fatigue in healthy and chronic low back pain subjects: A comparative study of 3 assessment protocols

OBJECTIVE

To compare the sensitivity of 3 different back test protocols in measuring differences in strength and fatigue between subjects with and without chronic low back pain (CLBP).

DESIGN

Descriptive study using a repeated-measures design.

SETTING

A research laboratory within a rehabilitation center.

PARTICIPANTS

Eighteen healthy subjects and 13 subjects with CLBP were assessed in a single session to compare the 3 protocols. The protocols were an upright position test (UPP), a semicrouched lifting test (LIF), and the Sorensen fatigue test.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Moments of force and surface electromyography were recorded bilaterally from 4 homologous back muscles while the subjects performed static trunk extension efforts for each protocol. Fatigue was quantified by the slopes of the linear regression of electromyography time-series.

RESULTS

The back muscle fatigue and strength scores did not differ significantly for the 2 subject groups for any of the 3 protocols. The electromyography fatigue indices revealed that the Sorensen fatigue test and UPP produced more fatigue in the back muscles than the LIF.

CONCLUSIONS

It was impossible to specify which protocol is more sensitive to low back status because no between-group difference was observed for any of the 3 tests.