Publications by authors named "Paulo Cezar Rocha dos Santos"

Mental fatigue can affect cognitive function and interfere with motor performance. We examined if mental fatigue affected gait through age-specific modulation of wavelet-based time-frequency intermuscular beta-band coherence in muscles while walking on a treadmill at 1.2 m·s-1.

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Article Synopsis
  • The study examined how beta-band intermuscular coherence (IMC) and corticomuscular coherence (CMC) changed with age and walking balance difficulty among younger (23 years) and older individuals (71 years).
  • Participants walked overground and on narrow beams to assess their balance and speed while measuring coherence between brain activity and leg muscle signals.
  • Results showed that walking balance decreased with difficulty for older adults, while CMC and IMC generally increased with age and walking challenge, indicating a greater reliance on neural control for maintaining balance, especially in older participants.
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Parkinson's Disease (PD)-typical declines in gait coordination are possibly explained by weakness in bilateral cortical and muscular connectivity. Here, we seek to determine whether this weakness and consequent decline in gait coordination is affected by dopamine levels. To this end, we compare cortico-cortical, cortico-muscular, and intermuscular connectivity and gait outcomes between body sides in people with PD under ON and OFF medication states, and in older adults.

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Background: Balance impairments in people with Parkinson's disease (PD) demonstrated mainly in challenging postural tasks, such as increased body oscillation may be attributed to the deficits in the brain structures functionality involved in postural control (e.g., motor cortex, midbrain, and brainstem).

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Scientific communication is crucial for the development of societies and the advancement of knowledge. However, many countries, and, consequently, their researchers, clinicians and community members, lack access to this information due to the information being disseminated in English rather than their native language. In this viewpoint, we aim to discuss the impacts of this problem and also outline recommendations for facilitating non-English speakers' access to current, evidence-based health information, thus extending the impact of science beyond academia.

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Objective: To determine the effects of low- vs. high-intensity aerobic and resistance training on motor and cognitive function, brain activation, brain structure, and neurochemical markers of neuroplasticity and the association thereof in healthy young and older adults and in patients with multiple sclerosis, Parkinson's disease, and stroke.

Design: Systematic review and robust variance estimation meta-analysis with meta-regression.

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Muscle weakness is a secondary motor symptom of Parkinson's disease (PD), especially in the subtype characterized by postural instability and gait difficulty (PIGD). Since the PIGD subtype also presents worse bradykinesia, we hypothesized that it also shows a decreased rate of force development, which is linked to an increased risk of falling in PD. Therefore, we investigated the effects of PD and PD subtypes on a force production profile and correlated the force production outcomes with clinical symptoms for each PD subtype.

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Repetitive sit-to-stand (rSTS) is a fatigue perturbation model to examine the age-effects on adaptability in posture and gait, yet the age-effects on muscle activation during rSTS are unclear. We examined the effects of age and exhaustive rSTS on muscle activation magnitude, onset, and duration during ascent and descent phases of the STS task. Healthy older ( = 12) and younger ( = 11) adults performed rSTS, at a controlled frequency dictated by a metronome (2 s for cycle), to failure or for 30 min.

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It is challenging for people with Parkinson's disease (PwPD) to adjust their gait to perturbations, including fatigue. Obstacle negotiation increases the risk of tripping and falling in PD. Being physically active can improve gait control and the ability to negotiate obstacles while walking under fatigue state.

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Falls are associated with impairment in postural control in people with Parkinson's disease (PwPD). We aimed to predict the fall risk through models combining postural responses with clinical and cognitive measures. Also, we compared the center of pressure (CoP) between PwPD fallers and non-fallers after unpredictable external perturbations.

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We examined the effects of age on intermuscular beta-band (15-35 Hz) coherence during treadmill walking before and after experimentally induced fatigue. Older (n = 12) and younger (n = 12) adults walked on a treadmill at 1.2 m/s for 3 min before and after repetitive sit-to-stand, rSTS, to induce muscle fatigability.

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Background: Parkinson's disease (PD) is a neurodegenerative and progressive disease marked by the presence of motor and non-motor symptoms, as psychological and cognitive impairment. Physical exercises have been prescribed as complementary therapy for PD, and the type of intervention and duration of the intervention should be taken into account.

Objective: We aimed to compare the effect of different exercise modalities (functional mobility, multimodal and cognitive) and length (4 and 8 months) on psychological and cognition in people with PD.

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Gait asymmetry during unobstructed walking in people with Parkinson's disease (PD) has been well documented. However, under complex situations, such as environments with double obstacles, gait asymmetry remains poorly understood in PD. Therefore, the aim of this study was to analyze inter-limb asymmetry while crossing a single obstacle and double obstacles (with different distances between them) in people with PD and healthy older adults.

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Introduction: While fatigue is ubiquitous in old age and visibly interferes with mobility, studies have not yet examined the effects of self-reported fatigue on healthy older adults' gait. As a model that simulates this daily phenomenon, we systematically reviewed eleven studies that compared the effects of experimentally induced muscle and mental performance fatigability on gait kinematics, variability, kinetics, and muscle activity in healthy older adults.

Methods: We searched for studies in databases (PubMed and Web of Science) using Fatigue, Gait, and Clinical conditions as the main terms and extracted the data only from studies that experimentally induced fatigue by sustained muscle or mental activities in healthy older adults.

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Background: Gait adaptability in old age can be examined by responses to various perturbations. Fatigability due to mental or muscle exercises can perturb internal cognitive and muscle resources, necessitating adaptations in gait.

Research Question: What are the effects of age and mental and muscle fatigability on stride outcomes and gait variability?

Methods: Twelve older (66-75yrs) and twelve young (20-25 yrs) adults walked at 1.

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Different clinical subtypes of Parkinson's disease (PD) have long been recognized. Recent studies have focused on two PD subtypes: Postural Instability and Gait Difficulty (PIGD) and Tremor Dominant (TD). PIGD patients have greater difficulties in postural control in relation to TD.

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The aim of this study was to determine the impact of aging and Parkinson's disease (PD) on lower limb muscle strength before and after muscle fatigue. One hundred thirty-five individuals were distributed over seven groups according to their age (20, 30, 40, 50, 60, 70 years old) and disease. Participants performed maximum voluntary isometric contractions (MVIC) in a leg press device followed by the muscle fatigue protocol (repeated sit-to-stand task).

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Our aim was investigating variability in spatiotemporal parameters and kinetics of obstacle avoidance steps of different height obstacles in people with Parkinson's disease (PD) and healthy older people. Twenty-eight participants have included (15 PD - stage disease: 2.1 ± 0.

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This study aimed to determine the relationship between postural asymmetry and falls in Parkinson's disease (PD). In total, 28 patients with PD were included. Postural control was analyzed in bipedal, tandem, and unipedal standing.

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The presence of a second obstacle changed the planning and adjustments for obstacle avoidance performance, but this context is poorly understood in Parkinson's disease (PD). The aim of this study was to investigate the walking behavior over multiple obstacles in people with PD. Nineteen people with PD and 19 healthy individuals walked across an 8m pathway, performing three trials for following conditions: unobstructed walking, walking with one obstacle avoidance (Single), and walking with two obstacles avoidance (Double).

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The authors' aim was to investigate gait asymmetry of crossing step during obstacle avoidance while walking in people with Parkinson's disease (PD) under and without the effects of dopaminergic medication. Thirteen individuals with PD and 13 neurologically healthy individuals performed 5 trials of unobstructed gait and 10 trials of obstacle crossing during gait (5 trials with each leg) and spatiotemporal parameters were analyzed. Obstacle crossing increased step duration of the crossing step for the most-affected or nondominant limb compared to the crossing step with the least-affected or dominant limb.

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The aim of this study was to investigate the effect of recovery time after quadriceps muscle fatigue on gait in young adults. Forty young adults (20-40 years old) performed three 8-m gait trials at preferred velocity before and after muscle fatigue, and after 5, 10 and 20min of passive rest. In addition, at each time point, two maximal isometric voluntary contractions were preformed.

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The current study evaluated the effects of disease severity on the control of obstacle crossing in people with idiopathic Parkinson's disease (PD). Forty-five subjects participated in the study, including 15 patients with mild PD (classified as stage 1 to 1.5 of the Hoehn and Yahr Rating Scale), 15 patients with moderate PD (classified as stage 2 to 3 of the Hoehn and Yahr Rating Scale), and 15 neurologically healthy individuals.

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Older adults commonly report muscle fatigue, which may be associated with reduced walking ability. Elderly may have insufficient awareness of the balance threat caused by muscle fatigue. The aim of this study was to analyze the interaction effects of aging and leg muscle fatigue on gait parameters in walking and obstacle crossing.

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