Thiago Lemos

• PhD Physiology
• Professor | Researcher at UNISUAM / FUNDACOR-INTO

Background: Little is discussed about the effectiveness and systematization of progressions of difficulty during balance exercises. Exercise progression provides continuous stimulation and assists physical therapists in offering challenges to patients. Objective: To investigate the effectiveness of an exercise program with systematic progression...

Background: The COVID-19 pandemic led to widespread social isolation and the suspension of sports activities, significantly impacting the physical and psychological performance of athletes worldwide, particularly soccer players. This study aims to evaluate the effects of pandemic-related training suspensions on the functional performance of U-20 so...

Background. Anterior cruciate ligament (ACL) tear is the most frequent ligament inju-ry in athletes and is often accompanied by a traumatic meniscus tear. When a patient issubmitted to a concomitant ACL reconstruction and meniscal repair, early rehabilita-tion caution might slightly delay knee function progress, potentially affecting gains inrange...

Objective. This study aims to investigate the effects of ACL injury on force fluctuationmeasures (stability and complexity) of the quadriceps muscle, and how these measuresrelate to functional performance.Methods. Forty-two athletes (14 females) with unilateral ACL injury were assessed.Quadriceps maximal isometric contraction was performed for both...

Background and purpose: Restricted dorsiflexion range of motion (DFROM) could impact dynamic balance in sports. This study aimed to investigate the relationship between dorsiflexion range of motion and the Y-Balance Test (YBT) in elite futsal players. Methods: Sixty-one asymptomatic male futsal players (mean age 26.57 (5.64) years, a mean body m...

Background: This study aimed to identify the postural sway variables that can distinguish between ballet dancers with high and low occurrences of musculoskeletal injuries. Methods: Fourteen professional ballet dancers were assigned to a high-occurrence group (N = 5, reports >2 injuries in the previous 6-months) or a low-occurrence group (N = 9,...

Falls in hospitalized older adults are of concern and, despite the availability of fall risk assessment methods and knowledge about factors associated with falls, their validity and agreement remain poorly investigated. In a prospective study, we enrolled 102 hospitalized older adults (median [P25-P75]) 67 (64-73) years, 52 [51%] men, length of sta...

Background The understanding of human postural control has advanced with the introduction of optimization process modeling. These models, however, only provide control parameters, rather than analytical descriptors of optimization processes. Here, we use a newly developed direct (pattern) search algorithm to investigate changes in postural optimiza...

Background: Postural instability with an excessive body sway is a disabling manifestation in spinocerebellar ataxia type 3. Whether the larger body sway reflects distinct movement strategies for postural control remains uncertain. This study compared the control of postural stability of people with spinocerebellar ataxia type 3 with healthy subjec...

The objective was to investigate the concurrent validity of inertial sensors for measuring balance control in patients with chronic low back pain and asymptomatic individuals. Thirty-nine patients with chronic low back and 39 age- and sex-matched asymptomatic individuals were included. Balance control analysis was performed in quiet standing with t...

Aim To investigate the correlation of lower-limb muscle function with clinical status, balance, and quality of life in individuals with Parkinson disease (PD). Methods Twenty-five participants were included. Outcome measures were assessed through scales and questionnaires. Quadriceps muscle function was assessed through a maximal isometric volunta...

Introduction Low back pain is highly prevalent worldwide and in Brazil. Postural control is a functional limitation in patients with low back pain. Postural control can be investigated through the centre of pressure (CoP) displacement, using a baropodometry. However, there is a lack of validation data about posturography variables obtained from the...

Lysophosphatidic acid (LPA) acts through the activation of G protein-coupled receptors, in a Ca2+-dependent manner. We show the effects of LPA on the plasma membrane Ca2+-ATPase (PMCA) from kidney proximal tubule cells. The Ca2+-ATPase activity was inhibited by nanomolar concentrations of LPA, with maximal inhibition (~50%) obtained with 20 nM LPA....

Background There is little evidence about the myofascial release maneuver (MLM) targeting the fascial tissue and its effect on postural balance. This study investigated the immediate effects of the MLM in different lower limb muscle chains on the postural sway of healthy men. Methods Sixty-three healthy men (27.2 ± 4.7 years) were randomly assigne...

Objectives Screening programs for fall prevention in older adults may include several assessment methods. This study investigated the validity of aggregating fall risk assessment methods for stratifying the risk of falling in older adults. Methods This secondary data analysis included 52 community-dwelling residents aged [median (interquartile ran...

Introdução: o Rugby em Cadeira de Rodas (RCR) é uma modalidade com grande demanda energética. Objetivo: comparar a recuperação cardiopulmonar de atletas de RCR de elite internacional (EI, n=16) e nacional (EN, n=06), além de investigar a correlação entre a recuperação e a classificação funcional (CF) dos atletas.Métodos: o teste de esforço cardiopu...

Background: Postural stability is quite mandatory when practicing high-performance sports. Investigations of postural stability and related variables in judokas with visual impairment can lead to new training plans targeting the improvement of postural stability and ultimately to enhanced performance. Objectives: To investigate postural stability a...

RESUMO A assimetria na distribuição do peso corporal (DPC) é um achado comum após um acidente vascular cerebral. Embora a posturografia seja considerada o padrão-ouro para a detecção da assimetria da DPC, exige equipamentos e conhecimentos específicos, limitando seu uso na prática clínica. Por outro lado, a Escala de Avaliação da Simetria e Transfe...

Background: Fatigue is a distressing symptom inversely related to postural stability in adults with neuromuscular and systemic diseases. However, there is no information about the effects of lower limb muscles fatigability on the movement strategies for balance control in the upright standing. Methods: This study enrolled 41 healthy subjects (fe...

Diagnostic value of static posturography depends on its methodological features, measurement properties, and on computational methods that extract meaningful information from the postural sway i.e. the center-of-pressure (CoP) displacements. In this study, we assessed the reliability and robustness of the postural system based on the optimization p...

A large number of fall risk assessment methods are available with a variety of performances for screening the risk of falling in older adults, but their agreement for assessing the risk of falling remains unknown. This observational prospective cohort study describes the agreement and predictive power of methods to classify the risk of falling in o...

Background This study investigated the whole-body stability dynamics during upright stance by applying a set of variables characterizing the mathematical optimization process that minimizes the postural sway as a cost-function. Method The downhill, stability, and convergence properties of postural sway were quantified by implementing a direct patt...

Neuromuscular adaptations are well-reported in stroke survivors. The death of motor neurons and the reinnervation of residual muscle fibers by surviving motor neurons, for example, seem to explain the increased density of muscle units after stroke. It is, however, unknown whether reinnervation takes place locally or extensively within the muscle. H...

Background One of the most disabling problems in Parkinson disease (PD) is gait impairment. Noninvasive brain stimulation techniques, such as transcranial direct current stimulation (tDCS), have been introduced as a therapeutic alternative for coping with PD motor problems. However, the effects of tDCS on gait performance in PD have not yet been fu...

Objective: The aim of the study was to provide a computerized photogrammetric description of the postural alignment of visually impaired athletes. Methods: Twenty-six athletes were evaluated. Athletes were asked to stand at easy with styrofoam balls placed on selected anatomical landmarks, and photographic images were acquired in four viewpoints. P...

Aims: This study proposed an exercise programme including strengthening and task-oriented training focussing on weight-bearing symmetry and examined its feasibility and safety for chronic stroke patients. Additionally, gait, balance and health status were assessed after the exercise programme implementation. Methodology: Fourteen individuals partic...

Objective: As highly social creatures, human beings rely part of their skills of identifying, interpreting, and predicting the actions of others on the ability of perceiving biological motion. In the present study, we aim to investigate the electroencephalographic (EEG) cerebral dynamics involved in the coding of postural control and examine whethe...

(Upper panel A) Unstable biological (UB) vs. Unstable scrambled (US)—Point-to-point paired T-test comparing the two conditions (UB vs. US) shows a higher positivity for UB in the central-parietal electrodes, while a pronounced negativity is verified in the right temporal and bilateral frontal regions (450–650 ms time window). (Upper panel B) Unstab...

Although some studies have reported significant changes in autonomic responses according to the perspective-taking during motor imagery [first person perspective (1P) and third person perspective (3P)], investigations on how the strategies adopted to mentally simulate a given movement affects the heart rate variability (HRV) seem so far unexplored....

Loss of vision is well known to affect postural control in blind subjects. This effect has classically been framed in terms of deficit or compensation depending on whether body sway increases or decreases in comparison with that of sighted subjects with the eyes open. However, studies have shown that postural responses can be modulated by the conte...

We aimed to evaluate the influence of wheelchair rugby (WR) classification and competitive level on the seated limits of stability of athletes with disabilities. Twenty-eight athletes were recruited from international and national level WR teams. Athletes were distributed into three groups per their classification: low-point (0.5–1.5-point); mid-po...

Objective: The main objective of this study was to review the literature to identify reference values for angles and distances of body segments related to upright posture in healthy adult women with the Postural Assessment Software (PAS/SAPO). Methods: Electronic databases (BVS, PubMed, SciELO and Scopus) were assessed using the following descri...

Purpose: The aim of this study was to evaluate whether different types of visual feedback influence the control of standing balance. Methods: Twenty-six subjects performed three tasks on a force platform: (1) standing with eyes open; (2) maintaining the own center of pressure (COP) displacement (internal feedback) on a target; and (3) pointing w...

Objective: The purpose of this case report is to describe the management of using a combination of hip strengthening and manipulative therapy (MT) for a patient with plantar fasciitis. Clinical features: A 44-year-old patient reported heel pain for approximately 1 year before treatment. The patient reported plantar heel pain and tenderness at th...

Objective: To investigate whether a sensorimotor deficit of the upper limb following a brachial plexus injury (BPI) affects the upright balance. Design: Eleven patients with a unilateral BPI and 11 healthy subjects were recruited. The balance assessment included the Berg Balance Scale (BBS), the number of feet touches on the ground while performing...

Objective. The present study aimed to characterize the functional capacity, disease status, cardiorespiratory fitness and quality of life of a sample of patients with spinocerebellar ataxia (SCA). The associations between these measures were also investigated. Methods. Fourteen individuals with SCA were included. Cardiorespiratory fitness was asses...

When individuals stand with their feet apart, activation of tibialis anterior (TA) muscle seems to slightly exceed rest levels. In narrow stances, conversely, the stabilization of body lateral sways may impose marked, active demand on ankle inversors/eversors. In this study we investigate how much the modulation in TA activity, associated to center...

Motor imagery (MI) performed in an upright stance promotes increases in postural sway without changes in usual amplitude measures of calf muscle EMG. However, postural muscle activity can also be determined from the temporal association between EMG and center of pressure (COP) displacements. In this study we investigated whether the MI modulation o...

In this study we investigate to what extent the effects of motor imagery on postural sway are constrained by movement features and the subject's imagery ability. Twenty-three subjects were asked to imagine three movements using the kinesthetic modality: rising on tiptoes, whole-body forward reaching, and whole-body lateral reaching. After each task...

Introdução. A imagética motora (IM) consiste na evocação do plano motor de uma dada ação sem que haja a execução do movimento. Objetivo. Realizar uma revisão e análise crítica sobre a IM, discutin­do as características neurofisiológicas, as diferenças entre as estratégias de simulação e sua aplicação clínica no contexto da reabilitação de pacientes...

Phosphatidylinositol-4 kinase (PI-4K) is responsible for the generation of phosphatidylinositol-4 phosphate (PtdIns(4)P), a bioactive signaling molecule involved in several biological functions. In this study, we show that sphingosine modulates the activity of the PI-4K isoform associated with the basolateral membranes (BLM) from kidney proximal tu...

Through the use of electromyography, insights have been gained into the understanding of intentional and reactive motor behaviors. This technique posits the detection and analysis of the electromyogram (EMG); the electrical potential produced during muscle contractions. EMGs can be detected either directly, by inserting electrodes in the muscle...

INTRODUÇÃO E OBJETIVO: Neste estudo investigamos a influência de diferentes protocolos ergométricos na ocorrência dos critérios de esforço máximo. MÉTODOS: Nove sujeitos fisicamente ativos (23 ± 4 anos, 177 ± 10cm, e 77,1 ± 16kg) realizaram três testes de esforço (PR1 - 15W·min-1, PR2 - 50W·3 min-1, e PR3 - 50W·5 min-1) no cicloergômetro. O consumo...

INTRODUÇÃO E OBJETIVO: Neste estudo investigamos a influência de diferentes protocolos ergométricos na ocorrência dos critérios de esforço máximo. MÉTODOS: Nove sujeitos fisicamente ativos (23 ± 4 anos, 177 ± 10cm, e 77,1 ± 16kg) realizaram três testes de esforço (PR1 - 15W·min-1, PR2 - 50W·3 min-1, e PR3 - 50W·5 min-1) no cicloergômetro. O consumo...

The aim of this study was to compare the intervals of time between adjacent zero crossings (ZCI), an alternative frequency-temporal parameter, with the root-mean-square (RMS) value and the median frequency (F(med)) from the surface EMG (sEMG) signal in muscle fatigue analysis. Twenty right-handed volunteers performed isometric contractions of right...

The aim of this study was to investigate the effect of imagining an action implicating the body axis in the kinesthetic and visual motor imagery modalities upon the balance control system. Body sway analysis (measurement of center of pressure, CoP) together with electromyography (EMG) recording and verbal evaluation of imagery abilities were obtain...

The aim of this study was to investigate (a) whether Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) participates in the regulation of plasma membrane Ca2+-ATPase and (b) its possible cross-talk with other kinase-mediated modulatory pathways of the pump. Using isolated innervated membranes of the electrocytes from Electrophorus electric...

Plasma membrane Ca2+-ATPase is involved in the fine-tuned regulation of intracellular Ca2+. In this study, the presence of Ca2+-ATPase in caveolae from kidney basolateral membranes was investigated. With the use of a discontinuous sucrose gradient, we show that Ca2+-ATPase is exclusively located and fully active in caveolin-containing microdomains....