Knee extensor strength, dynamic stability, and functional ambulation: are they related in Parkinson's disease?

High-intensity interval versus moderate-intensity continuous cycling training in Parkinson's disease: a randomized trial

Exercise training is recommended to improve the quality of life in those living with Parkinson's disease (PD); however, the optimal prescription to improve cardiorespiratory fitness and disease-related motor symptoms remains unknown. Twenty-nine participants with PD were randomly allocated to either 10 wk of high-intensity interval training (HIIT) (n = 15; 6 female) or moderate-intensity continuous training (MICT) (n = 14; 5 female). The primary outcome was the change in maximal oxygen consumption (V̇o2peak). Secondary outcomes included changes in the Unified Parkinson's Disease Rating Scale (UPDRS) Part III motor score, Parkinson's Fatigue Scale (PFS)-16, resting and exercise cardiovascular measures, gait, balance, and knee extensor strength and fatigability. Exercise training increased V̇o2peak (main effect of time, P < 0.01), with a clinically meaningful difference in the change following HIIT versus MICT (Δ3.7 ± 3.7 vs. 1.7 ± 3.2 mL·kg-1·min-1, P = 0.099). The UPDRS motor score improved over time (P < 0.001) but without any differences between HIIT versus MICT (Δ-9.7 ± 1.3 vs. -8.4 ± 1.4, P = 0.51). Self-reported subjective fatigue (PFS-16) decreased over time (P < 0.01) but was similar between HIIT and MICT groups (P = 0.6). Gait, balance, blood pressure (BP), and heart rate (HR) were unchanged with training (all P > 0.09). Knee extensor strength increased over time (P = 0.03) but did not differ between HIIT versus MICT (Δ8.2 ± 5.9 vs. 11.7 ± 6.2 Nm, P = 0.69). HIIT alone increased the muscular endurance of the knee extensors during an isotonic fatigue task to failure (P = 0.04). In participants with PD, HIIT and MICT both increased V̇o2peak and led to improvements in motor symptoms and perceived fatigue; HIIT may offer the potential for larger changes in V̇o2peak and reduced knee extensor fatigability.NEW & NOTEWORTHY The optimal exercise prescription to improve cardiorespiratory fitness and disease-related motor symptoms in adults with Parkinson's disease remains unknown. In a single-center randomized trial consisting of either 10 wk of high-intensity interval training (HIIT) or moderate-intensity continuous training (MICT), we found that both training modes increased V̇o2peak, with a larger clinically meaningful difference following HIIT. Both exercise modes improved motor symptoms and subjective fatigue, whereas HIIT increased the muscular endurance of the knee extensors.

Increased Auditory Dual Task Cost During Gait Initiation in Adult Patients With Persistent Concussion Symptoms

OBJECTIVE

To compare dual task cost (DTC) during gait initiation (GI) between a population of patients with persistent concussion symptoms (PCS) and age-matched healthy participants.

DESIGN

Cohort study.

SETTING

University research center.

PARTICIPANTS

A cohort sample including 15 participants with PCS (43.9±11.7y, 73.3% female) and 23 age-matched healthy participants (42.1±10.3y, 65.2% female) as controls.

INTERVENTIONS

Participants were tested on a single occasion where they performed 5 trials of single task and 5 trials of dual task GI with 12-camera motion capture and 3 force plates.

MAIN OUTCOME MEASURES

The dependent variables of interest were the DTC for the center of pressure (COP) displacement and velocity during the anticipatory postural adjustment (APA) phase, the COP-center of mass (COP-COM) separation, and the response accuracy during the auditory cognitive tasks.

RESULTS

There were significant group differences with worse DTC for the PCS participants in anterior (A)/posterior (P) displacement (PCS, -37.5±22.1%; Control, -9.7±39.2%; P=.016, d=0.874), APA medial (M)/lateral (L) velocity (PCS, -34.8±28.8%; Control, -17.0±40.21%; P=.041, d=0.866), and the peak COP-COM separation (PCS, -7.3±6.7%; Control, 0.6±6.5%; P=.023, d=1.200). There were no significant group differences in the APA A/P velocity (PCS, -38.8±33.1%; Control, -19.8±43.9%; P=.094), APA M/L displacement (PCS, -34.8±21.8%; Control, -10.6±25.3%; P=.313), or cognitive task performance (PCS, -2.7±10.8%; Control, -0.2±4.3%; P=.321).

CONCLUSIONS

PCS participants had greater (worse) DTC during both the planning and execution of the task, with large effect sizes (d>0.80). PCS participants also used a posture-second strategy whereby attentional resources were inappropriately allocated to the cognitive task. These deficits may challenge a patient's ability to complete activities of daily living and limit their functional independence.

Short-term effects of Pilates-based exercise on upper limb strength and function in people with Parkinson's disease

BACKGROUND

People with Parkinson's disease (PD) have impaired upper limb motor coordination, limiting the execution of activities of daily living. This study investigated the feasibility and safety of a short-term Pilates-based exercise program in the treatment of upper limb motor coordination for people with PD.

METHODS

Fifteen patients - n (%) 4 women/11 men (27/73), median [interquartile range] age 66 [9] years - participated in this quasi-experimental (before-and-after) clinical trial. Patients underwent a 6-week (30 min/day, 3 days/week) Pilates exercise program using Reformer, Cadillac, Chair, and Barrel equipment. Feasibility was evaluated by adherence to the program and the ability to perform the exercises including progressions on difficulty. Safety was evaluated based on self-reported adverse events. Clinical and functional trends before and after the intervention were also computed regarding handgrip strength (HGS), fine motor coordination (9 Hole Peg Test; 9HPT), bradykinesia (Movement Disorder Society - Unified Parkinson's disease Rating Scale; MDS-UPDRS), and upper limb functionality (Test D'évaluation des Membres Supérieurs des Personnes Âgées, TEMPA).

RESULTS

Of the 18 Pilates sessions, exercise adherence was 100%. The only adverse event observed was mild muscle pain. Pre-post differences were observed only for body bradykinesia and hypokinesia (1.0 [0.0] vs. 0.0 [1.0] s, adjusted p = 0.048).

CONCLUSIONS

A short-term Pilates-based exercise program in the treatment of upper limb muscle strength, manual dexterity, bradykinesia, and functionality is feasible and safe for people with PD. Changes in upper limb bradykinesia encourage randomized clinical trials.

Gender-Specific Differences in Spinal Alignment and Muscle Power in Patients with Parkinson's Disease

BACKGROUND

Parkinson's disease (PD) is an advancing neurodegenerative disorder characterized by spinal anomalies and muscular weakness, which may restrict daily functional capacities. A gender-focused examination of these effects could provide valuable insights into customized rehabilitation strategies for both sexes.

PURPOSE

This study investigates the influence of spinal alignment on lower-limb function during the sit-to-stand (STS) movement in patients with Parkinson's disease compared to healthy individuals.

METHODS

A cross-sectional study was conducted with 43 consecutive patients with PD (25 males and 18 females; average age 73.7 ± 7.1 years) and 42 healthy controls (22 males and 20 females; average age 69.8 ± 6.0 years). Assessments included the International Physical Activity Questionnaire (IPAQ), Hoehn and Yahr staging, and measurements of vertical deviations from several spinal landmarks. Lower-limb muscle power during the STS task was evaluated using the Muscle Quality Index (MQI).

RESULTS

Both absolute (Watts) and relative (Watts/Kg) muscle power in the lower limbs were notably decreased in the PD group compared to the control group. Within the PD cohort, muscle power showed a negative relationship with age and a positive association with the degree of lumbar lordosis (PL-L3). Importantly, gender-specific analysis revealed that male patients with PD had significantly higher lower-limb muscle power compared to female patients with PD, highlighting the need for gender-tailored therapeutic approaches.

CONCLUSIONS

The findings suggest that preserving lumbar lordosis is crucial for maintaining effective lower-limb muscle biomechanics in individuals with Parkinson's disease.

Long-term efficacy of hydrotherapy on balance function in patients with Parkinson's disease: a systematic review and meta-analysis

Background

Hydrotherapy can improve the motor and non-motor symptoms of Parkinson's disease (PD), but the long-term effects of hydrotherapy on PD are still unclear.

Objective

The purpose of this systematic evaluation and meta-analysis was to explore the long-term effects of hydrotherapy on balance function in PD patients.

Methods

A systematic search of five databases was conducted to identify appropriate randomized controlled trials (RCTs) according to the established inclusion and exclusion criteria. The general characteristics and outcome data (balance, exercise, mobility, quality of life, etc.) of the included studies were extracted, and the quality of the included studies was evaluated using the Cochrane risk of bias assessment tool. Finally, the outcome data were integrated for meta-analysis.

Results

A total of 149 articles were screened, and 5 high-quality RCTs involving 135 PD patients were included. The results of the meta-analysis showed positive long-term effects of hydrotherapy on balance function compared to the control group (SMD = 0.69; 95% CI = 0.21, 1.17; p = 0.005; I2 = 44%), However, there were no significant long-term effects of hydrotherapy on motor function (SMD = 0.06; 95% CI = -0.33, 0.44; p = 0.77; I2 = 0%), mobility and quality of life (SMD = -0.21; 95% CI = -0.98, 0.57; p = 0.6; I2 = 71%). Interestingly, the results of the sensitivity analysis performed on mobility showed a clear continuation effect of hydrotherapy on mobility compared to the control group (SMD = -0.80; 95% CI = -1.23, -0.37; p < 0.001; I2 = 0%).

Conclusion

The long-term effects of hydrotherapy on PD patients mainly focus on balance function, and the continuous effects on motor function, mobility, and quality of life are not obvious.

Association of activities of daily living, mobility and balance ability, and symptoms of Parkinson's disease with the masses and amounts of intramuscular non-contractile tissue of the trunk and lower extremity muscles in patients with Parkinson's disease

PURPOSE

We examined the association of activities of daily living (ADL), mobility and balance ability, and symptoms of Parkinson's disease (PD) with the masses and amounts of intramuscular non-contractile tissue of the trunk and lower extremity muscles in patients with PD.

METHODS

The subjects were 11 community-dwelling patients with PD. ADL were assessed using the Functional Independence Measure. Mobility capacity was assessed based on measurement of maximal walking speed and timed up-and-go time, while balance ability was evaluated based on measurement of one-legged stance time. The symptoms of PD were assessed based on measurement of the Hoehn and Yahr stage and Unified Parkinson's Disease Rating Scale. Muscle thickness (MT) and echo intensity (EI) of the trunk and lower extremity muscles were also measured using an ultrasound imaging device.

RESULTS

Partial correlation analysis revealed an association between reduced ADL and increased EI of the lumbar erector spinae muscle; reduced mobility capacity and increased EI of the rectus abdominis and gluteus minimus muscles; and reduced balance ability and decreased MT of the lumbar erector spinae muscle and increased EI of the lumbar erector spinae, semitendinosus, and tibialis posterior muscles. Partial correlation analysis also showed an association between symptoms of severe PD and decreased MT of the tibialis anterior muscles and increased EI of the lumbar erector spinae, gluteus minimus, and tibialis posterior muscles.

CONCLUSION

The properties of the trunk and lower extremity muscles may be critical for ADL, mobility and balance ability, and symptoms of PD in patients with PD.

Muscle strength and spatiotemporal gait parameters in people with Parkinson´s disease. A pilot study

INTRODUCTION

Muscle weakness in persons with Parkinson disease (PD) has been frequently recognized as a nonspecific symptom. In other neurological conditions, lower limb weakness, specifically quadriceps weakness, is the factor that causes greater gait disability. Little research has evaluated the relationship between lower limb muscle strength, using objective tools, in PD persons and gait performance. The aim of this study was to analyze the correlation between lower limb muscle strength, using an isokinetic dynamometer, and the spatiotemporal gait parameters in PD, compared with age- and sex- matched healthy controls.

SUBJECTS AND METHODS

The study was conducted with 7 persons with PD -Hoehn and Yahr (HY) between II-III- and 7 healthy controls. Isokinetic knee and ankle tests at 60 and 120°/s and the 10-meter walking test at comfortable and fast walking speed, were performed on all recruited subjects.

RESULTS

Significant differences in lower limb strength-related measures and gait parameters were observed between persons with PD and controls. Gait parameters showed excellent correlations (rho = 0.7) for both lower limb: ankle plantar flexion work/body wearing at 180°/s with number of steps (indirect) and stride (direct) at both speeds, and between the ankle plantar flexion peak torque/ body wearing at 180°/s with number of steps (indirect) and stride (direct) at maximum speed; and between knee extension work/body wearing at 60°/s) with stride (direct) at self-selected speed.

CONCLUSIONS

Persons with PD (HY II-III stages) lower limb muscle strength correlates excellently with gait pattern, showing lower isokinetic strength than healthy subjects of the same age and sex. This protocol showed safety to be performed in a larger sample.

Walking function determinants in parkinson patients undergoing rehabilitation

BACKGROUND: To date little is known about factors affecting walking rehabilitation in Parkinson’s disease (PD) patients. OBJECTIVE: This prospective observational cohort study evaluated the walking distance covered in 6 minutes (6 MWD) before and after conventional rehabilitation and verified which among PD motor disorders was the most important determinant of walking distance in PD patients undergoing rehabilitation. METHODS: Data were collected from 55 PD patients, performing a conventional outpatient motor rehabilitation program. The 6MWD at the end of rehabilitation and gain in 6MWD were the outcome measures. The Unified Parkinson’s Disease Rating Scale, Hoehn and Yahr scale, Nine Hole Peg Test, Grip and Pinch test, ROM wrist motility, and Berg Balance Scale (BBS) were used to assess PD patients at admission and were considered as dependent variables. Backward multiple regression analyses identified the determinants of 6MWD outcomes. RESULTS: The 6MWD was 246.58±115 meters at admission and 286.90±116 at the end of rehabilitation. At end of rehabilitation, the 6MWD was 42.32±47 meters greater than admission (p <  0.001), corresponding to an increase of +17.16% . At the end of rehabilitation, the 6MWD was significantly longer in PD patients with stages 1–3 of the Hoehn and Yahr scale. Berg Balance Scale (β= 0.47, p <  0.001) and right Grip and Pinch at admission (β= 0.36, p = 0.001) were the only determinants of final 6MWD. The R2 value of the model was 0.47 (R2 adjusted 0.45). No variable was a determinant of gain in 6MWD. CONCLUSIONS: The study indicates that balance and generalized muscle strength are important determinants of walking rehabilitation in PD patients, in whom it is essential to maintain high levels of balance and muscle strength for a time as long as possible. These findings suggest planning more intensive rehabilitation treatments in PD patients with low levels of balance and muscle strength.

Relationship between Lower Limbs Performance and Spinal Alignment in Parkinson’s Disease Patients: An Observational Study with Cross Sectional Design

Parkinson’s disease (PD) is a progressive neurodegenerative disease determining spinal deformities and muscle rigidity, weakness and dystonia that can be related to a change in muscular output during sit-to-stand tasks (STS). Purpose: The aim of this study was to determine the impacts of spinal alignment on lower limbs performance during STS tasks in Parkinson’s disease (PD) patients and healthy controls. Methods: In total, 43 consecutive PD patients (“PD” Group, 25 males and 18 females; age 73.7 ± 7.1) and 42 people not affected by any type of neurological disease (“CON” Group, 22 males, 20 females; age 69.8 ± 6.0) participated in the observational study. The clinical assessment included: IPAQ (International Physical Activity Questionnaire), Hoehn Yahr score, plumb-line distance from the spinous process of C7, kyphosis apex and the spinous process of L3 and S1. We used the Muscle Quality Index test (MQI) to assess muscle power output during STS in both groups. Results: The MQI test measurements of absolute and relative lower limb power was significantly lower in the PD group, in addition to a negative correlation with age and a positive correlation with PL-L3 in that group of patients. Conclusions: A final consideration regarding our results leads to the possibility that the preservation of lumbar lordosis may be one of the factors for maintaining efficient biomechanics of the lower limb muscles, with the preservation of the physiological contractile characteristics of these muscles being the objective for a multidisciplinary rehabilitation based on postural exercises of the spine and a program of training exercises for the lower limb muscles.

Leg Muscle Strength Correlates with Gait Performance in Advanced Parkinson Disease

Objective Leg muscle strength (LMS) is decreased in early-stage Parkinson disease (PD) patients and is associated with slower walking and falls. However, LMS in advanced PD has not been well investigated. The purpose of this study was to evaluate LMS in advanced PD patients and its effects on gait performance, activities of daily living, and the cognitive function. Methods The medical records of 132 patients with idiopathic advanced PD [Hoehn and Yahr (H&Y) stages 3 and 4] with a mean disease duration of 9.6 years were retrospectively reviewed. Leg extensor muscle strength of the patients was measured using a Strength Ergo 240. The associations between the LMS and gait performance, Barthel index, H&Y stage, and Mini-Mental State Examination (MMSE) score were analyzed. Results A Spearman's correlation analysis showed that LMS was correlated with the sex, age, age of disease onset, H&Y stage, Barthel index, MMSE score, and gait parameters. A multivariable linear regression analysis for identifying predictors of LMS showed that the gait velocity (β=0.377), Barthel index (β=0.281), sex (β=-0.187), and disease duration (β=-0.155) were significant. A receiver operating characteristic curve analysis for discriminating between H&Y stage 3 and 4 was performed for LMS; the area under the curve was 0.774 (95% confidence interval=0.696-0.851). Conclusions LMS was strongly associated with multiple domains of clinical characteristics, especially gait velocity and the Barthel index. Our study also suggested that LMS can be a predictor of PD progression.

The neuromuscular responses in patients with Parkinson's disease under different conditions during whole-body vibration training

BACKGROUND

Whole-body vibration (WBV) training can provoke reactive muscle response and thus exert beneficial effects in various neurological patients. This study aimed to investigate the muscles activation and acceleration transmissibility of the lower extremity to try to understand the neuromuscular control in the Parkinson's disease (PD) patients under different conditions of the WBV training, including position and frequency.

METHODS

Sixteen PD patients and sixteen controls were enrolled. Each of them would receive two WBV training sessions with 3 and 20 Hz mechanical vibration in separated days. In each session, they were asked to stand on the WBV machine with straight and then bended knee joint positions, while the vibration stimulation was delivered or not. The electromyographic (EMG) signals and the segmental acceleration from the lower extremity were recorded and processed. The amplitude, co-contraction indexes (CCI), and normalized median frequency slope (NMFS) from the EMG signals, and the acceleration transmissibility were calculated.

RESULTS

The results showed larger rectus femoris (RF) amplitudes under 3 Hz vibration than those in 20 Hz and no vibration conditions; larger tibialis anterior (TA) in 20 Hz than in no vibration; larger gastrocnemius (GAS) in 20 Hz than in 3 Hz and no vibration. These results indicated that different vibration frequencies mainly induced reactive responses in different muscles, by showing higher activation of the knee extensors in 3 Hz and of the lower leg muscles in 20 Hz condition, respectively. Comparing between groups, the PD patients reacted to the WBV stimulation by showing larger muscle activations in hamstring (HAM), TA and GAS, and smaller CCI in thigh than those in the controls. In bended knee, it demonstrated a higher RF amplitude and a steeper NMFS but smaller HAM activations than in straight knee position. The higher acceleration transmissibility was found in the control group, in the straight knee position and in the 3 Hz vibration conditions.

CONCLUSION

The PD patients demonstrated altered neuromuscular control compared with the controls in responding to the WBV stimulations, with generally higher EMG amplitude of lower extremity muscles. For designing WBV strengthening protocol in the PD population, the 3 Hz with straight or flexed knee protocol was recommended to recruit more thigh muscles; the bended knee position with 20 Hz vibration was for the shank muscles.

The relationships between knee extensors/ flexors strength and balance control in elite male soccer players

Background

Strength and balance are important factors for soccer players to be successful. This study’s aim was to determine the relationship between lower-limb muscle strength and balance control in elite male soccer players (n = 77).

Methods

Concentric isokinetic strength (peak torque of quadriceps (PT-Q) and hamstrings (PT-H), hamstrings/quadriceps (H/Q) ratio) was measured for the dominant and non-dominant leg at angular velocities of 60°s⁻¹and 240°s⁻¹, as well as the total work for extensors (TW-Q) and flexors (TW-H) for both legs (at an angular velocity of 240°s⁻¹only). Balance score (BAL score) was used for unilateral assessment of balance control using a Delos Postural System Test measurement tool. Hierarchical multiple regression analyses were performed to predict balance control using isokinetic knee strength performance for dominant and non-dominant legs.

Results

Final modelling included peak torque of hamstrings at 240°s⁻¹ and peak torque of the quadriceps at 240°s⁻¹ for the non-dominant leg (R² = 19.6%; p ≤ 0.001) and only peak hamstring torque at 240°s⁻¹ for the dominant leg (R² = 11.3%; p = 0.003) as significant predictors of balance score.

Conclusion

Findings indicate that balance control is widely influenced by peak hamstring torque and peak quadriceps torque at high angular velocity particularly in the non-dominant leg i.e., the supporting leg in soccer players.

Periodized Resistance Training With and Without Functional Training Improves Functional Capacity, Balance, and Strength in Parkinson's Disease

ABSTRACT

Strand, KL, Cherup, NP, Totillo, MC, Castillo, DC, Gabor, NJ, and Signorile, JF. Periodized resistance training with and without functional training improves functional capacity, balance, and strength in Parkinson's disease. J Strength Cond Res 35(6): 1611-1619, 2021-Periodized progressive resistance training (PRT) is a common method used to improve strength in persons with Parkinson's disease (PD). Many researchers advocate the addition of functional training to optimize translation to activities of daily living; however, machine-based PRT, using both force and velocity training components, may elicit similar benefits. Thirty-five persons with PD (Hoehn and Yahr I-III) were randomized into a strength, power, and hypertrophy (SPH; n = 17) or strength, power, and functional (SP + Func; n = 18) group, training 3 times weekly for 12 weeks. Both groups performed machine-based strength and power training on days 1 and 2 each week, respectively; whereas, on day 3, SPH group performed machine-based hypertrophy training and SP + Func group performed functional training. Functional performance was tested using the timed up and go, 30-second sit-to-stand (30-s STS), gallon-jug shelf-transfer, and seated medicine ball throw (SMBT) tests. Balance (Mini-BESTest), strength, motor symptoms (UPDRS-III), quality of life, and freezing of gait (FOG) were also assessed. Repeated measures analysis of variance revealed a main effect for time (p ≤ 0.05) with significant improvements for the sample in the 30-s STS (p = 0.002), SMBT (p = 0.003), Mini-BESTest (p < 0.001), upper-body strength (p = 0.002) and lower-body strength (p < 0.001). A significant group × time interaction was seen for FOG, with SP + Func alone showing improvement (p = 0.04). Furthermore, the SPH group produced a clinically important difference for the UPDRS-III (mean difference = 4.39, p = 0.18). We conclude that both exercise strategies can be equally effective at improving functional capacity, balance, and muscular strength in individuals with PD. In addition, FOG and motor symptoms may be targeted through SP + Func and SPH, respectively. The results provide options for individualized exercise prescriptions.

Multimodal Imaging of Brain Activity to Investigate Walking and Mobility Decline in Older Adults (Mind in Motion Study): Hypothesis, Theory, and Methods

Age-related brain changes likely contribute to mobility impairments, but the specific mechanisms are poorly understood. Current brain measurement approaches (e.g., functional magnetic resonance imaging (fMRI), functional near infrared spectroscopy (fNIRS), PET) are limited by inability to measure activity from the whole brain during walking. The Mind in Motion Study will use cutting edge, mobile, high-density electroencephalography (EEG). This approach relies upon innovative hardware and software to deliver three-dimensional localization of active cortical and subcortical regions with good spatial and temporal resolution during walking. Our overarching objective is to determine age-related changes in the central neural control of walking and correlate these findings with a comprehensive set of mobility outcomes (clinic-based, complex walking, and community mobility measures). Our hypothesis is that age-related walking deficits are explained in part by the Compensation Related Utilization of Neural Circuits Hypothesis (CRUNCH). CRUNCH is a well-supported model that describes the over-recruitment of brain regions exhibited by older adults in comparison to young adults, even at low levels of task complexity. CRUNCH also describes the limited brain reserve resources available with aging. These factors cause older adults to quickly reach a ceiling in brain resources when performing tasks of increasing complexity, leading to poor performance. Two hundred older adults and twenty young adults will undergo extensive baseline neuroimaging and walking assessments. Older adults will subsequently be followed for up to 3 years. Aim 1 will evaluate whether brain activity during actual walking explains mobility decline. Cross sectional and longitudinal designs will be used to study whether poorer walking performance and steeper trajectories of decline are associated with CRUNCH indices. Aim 2 is to harmonize high-density EEG during walking with fNIRS (during actual and imagined walking) and fMRI (during imagined walking). This will allow integration of CRUNCH-related hallmarks of brain activity across neuroimaging modalities, which is expected to lead to more widespread application of study findings. Aim 3 will study central and peripheral mechanisms (e.g., cerebral blood flow, brain regional volumes, and connectivity, sensory function) to explain differences in CRUNCH indices during walking. Research performed in the Mind in Motion Study will comprehensively characterize the aging brain during walking for developing new intervention targets.

Relationships between lower extremity strength and the multi-directional reach test in children aged 7 to 12 years

OBJECTIVE

This study investigates the relationships between the Multi-Directional Reach Test (MDRT) and lower extremity strength in typical children.

METHODS

The MDRT including forward, backward, leftward, and rightward directions was measured in 60 children aged between 7 and 12 years old with typical development. The lower extremity muscle groups were measured using a hand-held dynamometer.

RESULTS

The reaching score in each direction had positive relationships with the strengths of several lower extremity muscle groups ( r = 0 . 26 to 0 . 52 , p < 0 . 05 ) . Only the strengths of the hip flexor and knee flexor muscles significantly correlated with the MDRT scores in all directions ( r = 0 . 26 to 0 . 50 , p < 0 . 05 ) .

CONCLUSION

This study highlights the strength of the hip and knee flexor muscle groups as being important domain to control balance in all directions. These findings may be used for therapists in planning a balance program to improve the limits of stability.

Orthopedic Care of Patients with Parkinson Disease

This article summarizes existing literature examining orthopedic interventions for patients with Parkinson disease (PD). It reviews complications and functional outcomes of shoulder, spine, knee, and hip surgeries in PD. Causes of fall-related fractures in PD and the risk of postoperative cognitive decline after orthopedic interventions in PD are also briefly discussed.

Reliability and validity of knee extensor strength measurements using a portable dynamometer anchoring system in a supine position

Background

Muscle strength measurements using hand-held dynamometry (HHD) can be affected by the inadequate strength of the tester and lack of stabilization of the participants and the device. A portable HHD anchoring system was designed that enabled the measurement of isometric knee extensor muscle strength in a supine position. This can be used with individuals who are unable to assume the sitting position required for the measurement of knee extensor strength in conventional isokinetic dynamometry (IKD). The aim of this study was to evaluate the reliability and validity of knee extensor strength measurements using this device.

Methods

The maximal knee extensor isometric strength of the dominant leg in healthy adults aged 20 to 40 years was tested. Three trials of three contractions were assessed by two raters using the portable dynamometer anchoring system whilst the participant was in the supine position. After the three measurement trials, peak knee extensor torque was evaluated using IKD. The intraclass correlation coefficient (ICC) and 95% limits of agreement (LOA) for intra- and inter-rater reliability were obtained.

Results

Thirty-nine participants (19 male and 20 female, aged 30.08 ± 4.16 y), completed the three measurement trials. The ICC for intra-rater reliability was 0.98 for the maximum measurements of knee extensor strength (95% confidence interval [CI]: 0.96–0.98) and 0.98 (95% CI: 0.96–0.99) for inter-rater reliability. The mean difference (%) between the maximum knee extensor strength measurements of each trial was 1.02% (LOA range: − 11.13 to 13.16%) for intra-rater and − 1.44% (LOA range: − 13.98 to 11.08%) for inter-rater measurements. The Pearson correlation coefficient of the maximum voluntary peak torque measurements with the portable dynamometer anchoring system and IKD was 0.927.

Conclusions

The portable dynamometer anchoring system is a reliable and valid tool for measuring isometric knee extensor strength in a supine position. Future clinical feasibility studies are needed to determine if this equipment can be applied to people with severe illness or disabilities.

Trial registration

KCT0003041.

Electronic supplementary material

The online version of this article (10.1186/s12891-019-2703-0) contains supplementary material, which is available to authorized users.

Association of Strength and Physical Functions in People with Parkinson's Disease

Background

Parkinson's disease is responsible for decrease of activities of daily living and mobility limitations. Association of strength with physical capacities and disease time can improve training methodologies and predict changes in physical fitness for this population, since the control center of movements and strength is the same.

Objective

Therefore, the aim of this study is to analyze if there are correlation between strength with functional tests (the sit-to-stand, the six-minute walk, and the timed-up-go) and disease time in people with Parkinson's disease.

Results

All functional tests correlations are significant, p < 0.05. The strength is positively correlated with the sit-to-stand and the six-minute walk. The strength is negatively correlated with the timed-up-go.

Conclusion

There are a correlation between strength with functional tests in people with PD, and changes in strength assessment can be used as predictor to changes in aerobic capacity.

Association between Objectively Measured Physical Activity and Gait Patterns in People with Parkinson's Disease: Results from a 3-Month Monitoring

Background

Although physical activity (PA) is known to be beneficial in improving motor symptoms of people with Parkinson's disease (pwPD), little is known about the relationship between gait patterns and features of PA performed during daily life.

Objective

To verify the existence of possible relationships between spatiotemporal and kinematic parameters of gait and amount/intensity of PA, both instrumentally assessed.

Methods

Eighteen individuals affected by PD (10F and 8M, age 68.0 ± 10.8 years, 1.5 ≤ Hoehn and Yahr (H&Y) < 3) were required to wear a triaxial accelerometer 24 h/day for 3 consecutive months. They also underwent a 3D computerized gait analysis at the beginning and end of the PA assessment period. The number of daily steps and PA intensity were calculated on the whole day, and the period from 6:00 to 24:00 was grouped into 3 time slots, using 3 different cut-point sets previously validated in the case of both pwPD and healthy older adults. 3D gait analysis provided spatiotemporal and kinematic parameters of gait, including summary indexes of quality (Gait Profile Score (GPS) and Gait Variable Score (GVS)).

Results

The analysis of hourly trends of PA revealed the existence of two peaks located in the morning (approximately at 10) and in the early evening (between 18 and 19). However, during the morning time slot (06:00–12:00), pwPD performed significantly higher amounts of steps (4313 vs. 3437 in the 12:00–18:00 time slot, p < 0.001, and vs. 2889 in the 18:00–24:00 time slot, p=0.021) and of moderate-to-vigorous PA (43.2% vs. 36.3% in the 12:00–18:00 time slot, p=0.002, and vs. 31.4% in the 18:00–24:00 time slot, p=0.049). The correlation analysis shows that several PA intensity parameters are significantly associated with swing-phase duration (rho = −0.675 for sedentary intensity, rho = 0.717 for moderate-to-vigorous intensity, p < 0.001), cadence (rho = 0.509 for sedentary intensity, rho = −0.575 for moderate-to-vigorous intensity, p < 0.05), and overall gait pattern quality as expressed by GPS (rho = −0.498 to −0.606 for moderate intensity, p < 0.05) and GVS of knee flexion-extension (rho = −0.536 for moderate intensity, p < 0.05).

Conclusions

Long-term monitoring of PA integrated by the quantitative assessment of spatiotemporal and kinematic parameters of gait may represent a useful tool in supporting a better-targeted prescription of PA and rehabilitative treatments in pwPD.

Balance and fear of falling in subjects with Parkinson's disease is improved after exercises with motor complexity

Resistance training with instability (RTI) uses exercises with high motor complexity that impose high postural control and cognitive demands that may be important for improving postural instability and fear of falling in subjects with Parkinson's disease (PD). Here, we hypothesized that: 1) RTI will be more effective than resistance training (RT) in improving balance (Balance Evaluation Systems Test [BESTest] and overall stability index [Biodex Balance System^®]) and fear of falling (Falls Efficacy Scale-International [FES-I] score) of subjects with Parkinson's disease (PD); and 2) changes in BESTest and FES-I after RTI will be associated with changes in cognitive function (Montreal Cognitive Assessment [MoCA] score - previously published) induced by RTI. Thirty-nine subjects with moderate PD were randomly assigned to a nonexercising control, RT, and RTI groups. While RT and RTI groups performed progressive RT twice a week for 12 weeks, the RTI group added progressive unstable devices to increase motor complexity of the resistance exercises. There were significant group × time interactions for BESTest, overall stability index, and FES-I scores (P < 0.05). Only RTI improved BESTest, overall stability index and FES-I scores, and RTI was more effective than RT in improving biomechanical constraints and stability in gait (BESTest sections) at post-training (P < 0.05). There were strong correlations between relative changes in BESTest and MoCA (r = 0.72, P = 0.005), and FES-I and MoCA (r = -0.75, P = 0.003) after RTI. Due to the increased motor complexity in RTI, RTI is recommended for improving balance and fear of falling, which are associated with improvement in cognitive function of PD.

Evidence of compensatory joint kinetics during stair ascent and descent in Parkinson's disease

BACKGROUND

Stair ambulation is a challenging activity of daily life that requires larger joint moments than walking. Stabilisation of the body and prevention of lower limb collapse during this task depends upon adequately-sized hip, knee and ankle extensor moments. However, people with Parkinson's disease (PD) often present with strength deficits that may impair their capacity to control the lower limbs and ultimately increase their falls risk.

OBJECTIVE

To investigate hip, knee and ankle joint moments during stair ascent and descent and determine the contribution of these joints to the body's support in people with PD.

METHODS

Twelve PD patients and twelve age-matched controls performed stair ascent and descent trials. Data from an instrumented staircase and a three-dimensional motion analysis system were used to derive sagittal hip, knee and ankle moments. Support moment impulses were calculated by summing all extensor moment impulses and the relative contribution of each joint was calculated.

RESULTS

Linear mixed model analyses indicated that PD patients walked slower and had a reduced cadence relative to controls. Although support moment impulses were typically not different between groups during stair ascent or descent, a reduced contribution by the ankle joint required an increased knee joint contribution for the PD patients.

CONCLUSIONS

Despite having poorer knee extensor strength, people with PD rely more heavily on these muscles during stair walking. This adaptation could possibly be driven by the somewhat restricted mobility of this joint, which may provide these individuals with an increased sense of stability during these tasks.

Effects and feasibility of exercise therapy combined with branched-chain amino acid supplementation on muscle strengthening in frail and pre-frail elderly people requiring long-term care: a crossover trial

This study examined the effects and feasibility of a twice-weekly combined therapy of branched-chain amino acids (BCAAs) and exercise on physical function improvement in frail and pre-frail elderly people requiring long-term care. We used a crossover design in which the combination of exercise and nutritional interventions was carried out twice a week during cycles A (3 months) and B (3 months) and the exercise intervention alone was performed during the washout period. The exercise intervention entailed the following 5 training sets: 3 sets of muscle training at 30% of maximum voluntary contraction, 1 set of aerobic exercise, and 1 set of balance training. For the nutritional intervention, 6 g of BCAAs or 6 g of maltodextrin was consumed 10 min before starting the exercise. We determined upper and lower limb isometric strength, performance on the Functional Reach Test (FRT) and the Timed Up and Go test, and activity level. In the comparison between the BCAA group and the control group after crossover, the improvement rates in gross lower limb muscle strength (leg press, knee extension) and FRT performance were significantly greater (by approximately 10%) in the BCAA group. In the comparison between different orders of BCAA administration, significant effects were shown for the leg press in both groups only when BCAAs were given. The combination of BCAA intake and exercise therapy yielded significant improvements in gross lower limb muscle strength and dynamic balance ability.

Resistance versus Balance Training to Improve Postural Control in Parkinson's Disease: A Randomized Rater Blinded Controlled Study

Background

Reduced muscle strength is an independent risk factor for falls and related to postural instability in individuals with Parkinson’s disease. The ability of resistance training to improve postural control still remains unclear.

Objective

To compare resistance training with balance training to improve postural control in people with Parkinson’s disease.

Methods

40 patients with idiopathic Parkinson’s disease (Hoehn&Yahr: 2.5–3.0) were randomly assigned into resistance or balance training (2x/week for 7 weeks). Assessments were performed at baseline, 8- and 12-weeks follow-up: primary outcome: Fullerton Advanced Balance (FAB) scale; secondary outcomes: center of mass analysis during surface perturbations, Timed-up-and-go-test, Unified Parkinson’s Disease Rating Scale, Clinical Global Impression, gait analysis, maximal isometric leg strength, PDQ-39, Beck Depression Inventory. Clinical tests were videotaped and analysed by a second rater, blind to group allocation and assessment time.

Results

32 participants (resistance training: n = 17, balance training: n = 15; 8 drop-outs) were analyzed at 8-weeks follow-up. No significant difference was found in the FAB scale when comparing the effects of the two training types (p = 0.14; effect size (Cohen’s d) = -0.59). Participants from the resistance training group, but not from the balance training group significantly improved on the FAB scale (resistance training: +2.4 points, Cohen’s d = -0.46; balance training: +0.3 points, Cohen’s d = -0.08). Within the resistance training group, improvements of the FAB scale were significantly correlated with improvements of rate of force development and stride time variability. No significant differences were found in the secondary outcome measures when comparing the training effects of both training types.

Conclusions

The difference between resistance and balance training to improve postural control in people with Parkinson’s disease was small and not significant with this sample size. There was weak evidence that freely coordinated resistance training might be more effective than balance training. Our results indicate a relationship between the enhancement of rate of force development and the improvement of postural control.

Trial Registration

ClinicalTrials.gov ID: NCT02253563

Does attentional focus during balance training in people with Parkinson’s disease affect outcome? A randomised controlled clinical trial

Objective:

To compare the effects of attentional focus to augment balance outcomes in individuals with Parkinson’s disease.

Design:

Randomised controlled clinical trial.

Setting:

University gait and balance research laboratory.

Participants:

Forty-nine individuals with idiopathic Parkinson’s disease.

Interventions:

Participants were randomly assigned into one of four groups (three balance intervention groups and one control). The three intervention groups all received the same 4-week balance training program augmented with either external, internal, or no focus instructions. The control group did not receive any balance training.

Main measures:

Outcomes were measured at baseline, post intervention, 2-weeks post intervention, and 8-weeks post intervention and included: Sensory Organization Test, Berg Balance Scale, Self-Selected Gait Velocity, Dynamic Gait Index, Activities-Specific Balance Confidence Scale, and obstacle course completion time.

Results:

There were no differences among the groups in trajectory over the course of the trial for all outcomes (ps ⩾ .135). All groups improved from baseline to post intervention and from baseline to 2-weeks post intervention for all outcomes (ps ⩽ .003), except Self-Selected Gait Velocity, which did not change over the course of the trial ( P = .121).

Conclusions:

Attentional focus instructions to augment a 4-week balance training program did not result in any change over and above a control group in measures of gait and balance in individuals with Parkinson’s disease. Additionally, while all four groups improved, there was no difference among the groups, including the control, suggesting that the 4-week balance training program in this trial was not effective.

Effectiveness of resistance training on muscle strength and physical function in people with Parkinson’s disease: a systematic review and meta-analysis

Objectives:

To systematically review the evidence investigating the effectiveness of resistance training on strength and physical function in people with Parkinson’s disease.

Data sources:

Seven electronic databases (COCHRANE, CINAHL, Medline ISI, Psycinfo, Scopus, Web of Science ISI and Embase) were systematically searched for full-text articles published in English between 1946 and November 2014 using relevant search terms.

Review methods:

Only randomized controlled trials investigating the effects of resistance training on muscle strength and physical function in people with Parkinson’s disease were considered. The PEDro scale was used to assess study quality. Studies with similar outcomes were pooled by calculating standardized mean differences (SMD) using fixed or random effects model, depending on study heterogeneity.

Results:

Seven studies, comprising of 401 participants with early to advanced disease (Hoehn & Yahr stage 1 to 4), were included. The median quality score was 6/10. The meta-analyses demonstrated significant SMD in favour of resistance training compared to non-resistance training or no intervention controls for muscle strength (0.61; 95% CI, 0.35 to 0.87; P <0.001), balance (0.36; 95% CI, 0.08 to 0.64; P = 0.01) and parkinsonian motor symptoms (0.48; 95% CI, 0.21 to 0.75; P < 0.001) but not for gait, balance confidence and quality of life.

Conclusion:

This review demonstrates that moderate intensity progressive resistance training, 2-3 times per week over 8-10 weeks can result in significant strength, balance and motor symptoms gains in people with early to moderate Parkinson’s disease.

Factors influencing obstacle crossing performance in patients with Parkinson's disease

BACKGROUND

Tripping over obstacles is the major cause of falls in community-dwelling patients with Parkinson's disease (PD). Understanding the factors associated with the obstacle crossing behavior may help to develop possible training programs for crossing performance. This study aimed to identify the relationships and important factors determining obstacle crossing performance in patients with PD.

METHODS

Forty-two idiopathic patients with PD (Hoehn and Yahr stages I to III) participated in this study. Obstacle crossing performance was recorded by the Liberty system, a three-dimensional motion capture device. Maximal isometric strength of the lower extremity was measured by a handheld dynamometer. Dynamic balance and sensory integration ability were assessed using the Balance Master system. Movement velocity (MV), maximal excursion (ME), and directional control (DC) were obtained during the limits of stability test to quantify dynamic balance. The sum of sensory organization test (SOT) scores was used to quantify sensory organization ability.

RESULTS

Both crossing stride length and stride velocity correlated significantly with lower extremity muscle strength, dynamic balance control (forward and sideward), and sum of SOT scores. From the regression model, forward DC and ankle dorsiflexor strength were identified as two major determinants for crossing performance (R(2) = .37 to.41 for the crossing stride length, R(2) = .43 to.44 for the crossing stride velocity).

CONCLUSIONS

Lower extremity muscle strength, dynamic balance control and sensory integration ability significantly influence obstacle crossing performance. We suggest an emphasis on muscle strengthening exercises (especially ankle dorsiflexors), balance training (especially forward DC), and sensory integration training to improve obstacle crossing performance in patients with PD.

Balance and Gait Training With Augmented Feedback Improves Balance Confidence in People With Parkinson’s Disease

Background. Fear of falling has been identified as an important and independent fall-risk predictor in patients with Parkinson’s disease (PD). However, there are inconsistent findings on the effects of balance and gait training on balance confidence. Objective. To explore whether balance and gait training with augmented feedback can enhance balance confidence in PD patients immediately after treatment and at 3- and 12-month follow-ups. Methods. A total of 51 PD patients were randomly assigned to a balance and gait training (BAL) group or to an active control (CON) group. The BAL group received balance and gait training with augmented feedback, whereas CON participants received lower-limb strength training for 12 weeks. Outcome measures included Activities-Specific Balance Confidence (ABC) Scale, limits-of-stability test, single-leg-stance test, and spatiotemporal gait characteristics. All tests were administered before intervention (Pre), immediately after training (Post), and at 3 months (Post3m) and 12 months (Post12m) after treatment completion. Results. The ABC score improved marginally at Post and significantly at Post3m and Post12m only in the BAL group ( P < .017). Both participant groups increased their end point excursion at Post, but only the BAL group maintained the improvement at Post3m. The BAL group maintained significantly longer time-to-loss-of-balance during the single-leg stance test than the CON group at Post3m and Post12m ( P < .05). For gait characteristics, both participant groups increased gait velocity, but only the BAL group increased stride length at Post, Post3m, and Post12m ( P < .017). Conclusions. Positive findings from this study provide evidence that BAL with augmented feedback could enhance balance confidence and balance and gait performance in patients with PD.

Influência do fortalecimento muscular no equilíbrio e qualidade de vida em indivíduos com doença de Parkinson

Esse estudo teve como objetivo avaliar o efeito do fortalecimento muscular no equilíbrio, mobilidade e na qualidade de vida (QV) de indivíduos com doença de Parkinson (DP), e verificar a correlação entre fortalecimento muscular e qualidade de vida. Participaram do estudo nove sujeitos, de ambos os sexos, com diagnóstico médico de DP. Eles, inicialmente, passaram por avaliação do equilíbrio e da mobilidade funcional por meio da Escala de Equilíbrio de Berg (EEB) e teste Timed Up and Go (TUG) e da QV pelo questionário Parkinson's Disease Questionnaire (PDQ-39). Os sujeitos realizaram ainda o teste de determinação de carga máxima (1 RM) para os grupos musculares treinados. Depois de verificadas a normalidade e homogeneidade dos dados, foram realizados o teste t de Student e o teste de correlação de Spearman. Foi considerado nível de significância de p<0,05. Foi verificada melhora no equilíbrio (p=0,008) e na QV (p=0,013), e correlação negativa entre equilíbrio e QV (avaliação r=-0,65 e p=0,05; e na reavaliação r=-0,82 e p=0,005). O fortalecimento muscular foi eficaz na melhora no equilíbrio e na qualidade de vida de indivíduos com doença de Parkinson.

Effect of externally cued training on dynamic stability control during the sit-to-stand task in people with Parkinson disease

BACKGROUND

Previous studies have shown that people with Parkinson disease (PD) have difficulty performing the sit-to-stand task because of mobility and stability-related impairments. Despite its importance, literature on the quantification of dynamic stability control in people with PD during this task is limited.

OBJECTIVE

The study objective was to examine differences in dynamic stability control between people with PD and people who were healthy and the extent to which externally cued training could improve such control during the sit-to-stand task in people with PD.

DESIGN

This was a quasi-experimental controlled trial.

METHODS

The performance of 21 people with PD was compared with that of 12 older adults who dwelled in the community. People with PD were randomly assigned to 2 groups: a group that did not receive training and a group that received audiovisually cued training (3 times per week for 4 weeks) for speeding up performance on the sit-to-stand task. Outcome measures recorded at baseline and after 4 weeks included center-of-mass position, center-of-mass velocity, and stability against either backward or forward balance loss (backward or forward stability) at seat-off and movement termination.

RESULTS

Compared with people who were healthy, people with PD had greater backward stability resulting from a more anterior center-of-mass position at seat-off. This feature, combined with decreased forward stability at movement termination, increased their risk of forward balance loss at movement termination. After training, people with PD achieved greater backward stability through increased forward center-of-mass velocity at seat-off and reduced the likelihood of forward balance loss at movement termination through a posterior shift in the center-of-mass position.

LIMITATIONS

The study applied stability limits derived from adults who were healthy to people with PD, and the suggested impact on the risk of balance loss and falling is based on these theoretical stability limits.

CONCLUSIONS

For people with PD, postural stability against backward balance loss at task initiation was increased at the expense of possible forward balance loss at task termination. Task-specific training with preparatory audiovisual cues resulted in improved overall dynamic stability against both forward and backward balance loss.

iGAIT: an interactive accelerometer based gait analysis system

This paper presents a software program (iGAIT) developed in MATLAB, for the analysis of gait patterns extracted from accelerometer recordings. iGAIT provides a user-friendly graphical interface to display and analyse gait acceleration data recorded by an accelerometer attached to the lower back of subjects. The core function of iGAIT is gait feature extraction, which can be used to derive 31 features from acceleration data, including 6 spatio-temporal features, 7 regularity and symmetry features, and 18 spectral features. Features extracted are summarised and displayed on screen, as well as an option to be stored in text files for further review or analysis if required. Another unique feature of iGAIT is that it provides interactive functionality allowing users to manually adjust the analysis process according to their requirements. The system has been tested under Window XP, Vista and Window 7 using three different types of accelerometer data. It is designed for analysis of accelerometer data recorded with sample frequencies ranging from 5 Hz to 200 Hz.

Spatiotemporal variability during gait initiation in Parkinson's disease

During gait initiation (GI), consistency of foot placement while stepping is important in making successful transitions from a state of stable static posture to an unstable state of dynamic locomotion. In populations characterized by gait dysfunction and postural instability, such as persons with Parkinson's disease (PD), the ability to generate a consistent stepping pattern during GI may be essential in the prevention of falls. However, little is known about GI variability in persons with PD as compared to their healthy elderly peers. Therefore, this study investigated spatiotemporal variability during the first two steps of GI in 46 persons with idiopathic PD and 49 healthy age-matched adults. Stepping characteristics, including the length, width, and time of the first two steps of GI as well as their coefficients of variation (CV) were compared between groups. Persons with PD initiated gait with significantly shorter steps (swing step length=.463 vs. .537 m, stance step length=.970 vs. 1.10 m) and higher variability in step length (swing step CV=8.82 vs. 5.45, stance step CV=6.76 vs. 3.61). Persons with PD also showed significantly higher variability in the time of the swing step (swing step CV=10.0 vs. 7.4). GI variability did not differ significantly between disease stages in persons with PD. Because greater variability in these measures during gait is related to an increased risk of falls, we propose that higher GI variability may play a considerable role in falls frequently observed during transitions from quiet standing in PD.

Progressive resistance training improves gait initiation in individuals with Parkinson's disease

An impaired ability to initiate walking is a common feature of postural instability and gait impairment in Parkinson's disease. While progressive resistance training (PRT) has been proposed to be an effective modality to improve balance and gait function in people with Parkinson's disease, there are a limited number of randomized trials and no studies have evaluated gait initiation performance. Thus, the purpose of this study was to examine the potential benefits PRT on GI performance in people with Parkinson's disease. Eighteen individuals with idiopathic PD were randomly assigned to either a twice weekly PRT program or a non-contact control group for 10 weeks. Biomechanical analysis of GI was performed pre- and post-intervention. Dependent variables of interest included the displacement of the center-of-pressure (COP) during the anticipatory postural phase of GI as well as the initial stride length and velocity. The PRT group demonstrated improvements in the posterior displacement of the COP and the initial stride length and velocity. There were no improvements in any variables for the control subjects. These results suggest that PRT may be an effective non-pharmacological and nonsurgical treatment to improve GI performance in PWP.

Reliability in one-repetition maximum performance in people with Parkinson's disease

Strength training is an effective modality to improve muscular strength and functional performance in people with Parkinson's disease (PWP). One-repetition maximum (1-RM) is the gold standard assessment of strength; however, PWP suffer from day-to-day variations in symptom severity and performance characteristics, potentially adversely affecting the reliability of 1-RM performance. Herein, we assessed the reliability of 1-RM in PWP. Forty-six participants completed two sessions of 1-RM testing of knee extension, knee flexion, chest press, and biceps curl at least 72 hours apart. Significantly differences between testing sessions were identified for knee extension (P < 0.001), knee flexion (P = 0.042), and biceps curl (P = 0.001); however, high reliability (ICC > 0.90) was also identified between sessions. Interestingly, almost third of subjects failed to perform better on the second testing session. These findings suggest that 1-RM testing can be safely performed in PWP and that disease-related daily variability may influence 1-RM performance.

Physical, occupational, speech and swallowing therapies and physical exercise in Parkinson's disease

Former studies on the effects of physical exercise, physical and occupational therapy (PT, OT) and speech and swallowing therapy (ST, SwT) in Parkinson's disease (PD) have demonstrated little or uncertain effects. New pathophysiological concepts have been developed. Recent controlled high-level studies demonstrate improvement of mobility and balance after training of muscular strength and endurance, trunk control, and amplitude and rhythmicity of movements (treadmill). Attentional and cognitive strategies were found to enforce body awareness and improve movement sequences. Dance, sensory (auditory, visual, tactile) and cognitive cueing are effective for problems of gait and balance. Whether PT and OT reduce the risk of falls remains uncertain. ST including Lee Silverman Voice Treatment has been shown to relieve speech problems. SwT and OT are frequently applied, however, further studies are necessary. Therapeutic interventions need to be evaluated with regard to consistency, intensity, frequency, duration, side effects, home versus institution based and standardized versus individualized training, quality standards, practicability in real life, and cost-effectiveness. Parkinson patients should resume or continue physical exercise as long as possible. There is hope that regular sport may modify PD risk and progression.