The Adapted Resistance Training with Instability Randomized Controlled Trial for Gait Automaticity.

BACKGROUND: Deficits in the cerebellar locomotor region (CLR) have been associated with loss of gait automaticity in individuals with freezing of gait in Parkinson's disease (freezers); however, exercise interventions that restore gait automaticity in freezers are lacking. We evaluated the effects of the adapted resistance training with instability ([ARTI] complex exercises) compared with traditional motor rehabilitation (without complex exercises) on gait automaticity and attentional set-shifting. We also verified associations between gait automaticity change and CLR activation change previously published. METHODS: Freezers were randomized either to the experimental group (ARTI, n = 17) or to the active control group (traditional motor rehabilitation, n = 15). Both training groups performed exercises 3 times a week for 12 weeks. Gait automaticity (dual-task and dual-task cost [DTC] on gait speed and stride length), single-task gait speed and stride length, attentional set-shifting (time between Trail Making Test parts B and A), and CLR activation during a functional magnetic resonance imaging protocol of simulated step initiation task were evaluated before and after interventions. RESULTS: Both training groups improved gait parameters in single task (P < 0.05), but ARTI was more effective than traditional motor rehabilitation in improving DTC on gait speed, DTC on stride length, dual-task stride length, and CLR activation (P < 0.05). Changes in CLR activation were associated with changes in DTC on stride length (r = 0.68, P = 0.002) following ARTI. Only ARTI improved attentional set-shifting at posttraining (P < 0.05). CONCLUSIONS: ARTI restores gait automaticity and improves attentional set-shifting in freezers attributed to the usage of exercises with high motor complexity. © 2020 International Parkinson and Movement Disorder Society.

Minimal Detectable Change for Balance Using the Biodex Balance System in Patients with Parkinson Disease.

BACKGROUND: Minimal detectable change (MDC) when assessing balance using the Biodex Balance System (BBS) in patients with Parkinson disease (PD) is currently unknown, limiting the interpretability of the scores. OBJECTIVE: To determine the MDC on the Anterior/Posterior Stability Index (APSI), Medial/Lateral Stability Index (MLSI), and Overall Stability Index (OSI) from postural stability and fall risk protocols of the BBS in patients with PD. DESIGN: This was a repeated-measures design (at a 1-week interval). SETTING: Strength training laboratory of a public university. PATIENTS: 46 patients with PD (men and women) at stages 2 and 3 (67.9 ± 7.4 years old) were assessed in the "on" state (fully medicated). METHODS: Patients performed three trials of 20 s for each protocol. MAIN OUTCOME MEASUREMENTS: Absolute and relative MDC (MDC%) calculated for APSI, MLSI, and OSI from the postural stability (stable condition) and fall risk protocols (unstable condition). RESULTS: For the postural stability, the MDC and MDC% were 0.26° and 17% for APSI, 0.41° and 21% for MLSI, and 0.22° and 12% for OSI, respectively. For the fall risk, the MDC and MDC% were 0.51° and 18% for APSI, 0.21° and 15% for MLSI, and 0.41° and 20% for OSI, respectively. These results were considered acceptable, despite indices with high MDC for MLSI (postural stability) and APSI (fall risk). CONCLUSIONS: Patients with PD have more mediolateral and anteroposterior changes in the stable and unstable conditions, respectively. These abnormal balance strategies can occur principally due to postural instability of PD. However, our results demonstrated acceptable MDCs in both conditions in all of the assessed axes. Thus, BBS should be incorporated into the clinical evaluation to help therapists to determine if intervention-induced changes in balance are clinically significant or due to measurement error. LEVEL OF EVIDENCE: II.