Motoneuronal persistent inward currents (PICs) are facilitated by neuromodulatory inputs but are highly sensitive to local inhibitory circuits. Estimates of PICs are reduced by group Ia reciprocal inhibition, and increased with the diffuse actions of neuromodulators released during remote muscle contraction. However, it remains unknown how motoneurons function in the presence of simultaneous excitatory and inhibitory commands.
View Article and Find Full Text PDFRestrictions to control the COVID-19 pandemic have caused older adults to stop their usual activities, including physical exercises. The novel approach of isometric no-load resistance training (NLRT) can be an interesting alternative to conventional training to oppose the harmful effects of detraining. We described the design and preliminary evaluation of an eight-week, twice-weekly NLRT program for older adults returning to strength training programs after COVID-19 lockdown.
View Article and Find Full Text PDFThere are numerous studies comparing young and old adults in terms of muscle coordination in standard tasks (e.g., walking, reaching) and small variations of them.
View Article and Find Full Text PDFMotoneuronal persistent inward currents (PICs) are both facilitated by neuromodulatory inputs and highly sensitive to local inhibitory circuits (e.g., Ia reciprocal inhibition).
View Article and Find Full Text PDFEur J Sport Sci
November 2023
To examine the effect of ankle position (i.e. gastrocnemius muscle length) on training outcomes during leg curl exercise, we recruited untrained and trained healthy adults to participate in two separate experiments.
View Article and Find Full Text PDFNoninvasive recordings of motor unit (MU) spike trains help us understand how the nervous system controls movement and how it adapts to various physiological conditions. The majority of participants in human and nonhuman animal physiology studies are male, and it is assumed that mechanisms uncovered in these studies are shared between males and females. However, sex differences in neurological impairment and physical performance warrant the study of sex as a biological variable in human physiology and performance.
View Article and Find Full Text PDFThis study investigated the effects of the pre-exhaustion method on electromyographic activity (root mean square and median frequency) at different interval sets. Twenty adults with little or no experience in strength training performed the seated row exercise until muscular failure, with or without completing a previous pre-exhaustion set in a pullover exercise. Surface electrodes were placed over the latissimus dorsi, teres major, biceps brachii, and posterior deltoid muscles of the dominant side.
View Article and Find Full Text PDFRes Q Exerc Sport
March 2023
Identifying the magnitude of ball rotation is critical to reduce response time, aiming to improve table tennis performance. This study analyzed the influence of auditory and visual information on the perception accuracy and counterattack performance of table tennis players. Twenty-two high-level table tennis players (22.
View Article and Find Full Text PDFJ Ultrasound Med
November 2021
Objective: Focused US examinations of the liver in the routine hepatocellular carcinoma (HCC) screening reduce the time spent on evaluating other structures deemed irrelevant to the clinical setting. It is still unknown, however, if such a strategy may additionally improve the frequency of nodules detection. We aimed to assess the impact of an HCC surveillance program in high-risk patients by means of targeted liver US following LI-RADS technical guidelines in comparison to a complete upper abdominal scan.
View Article and Find Full Text PDFThe overweight population is growing in the world, and the search for obesity-associated mechanisms is important for a better understanding of this disease. Few studies with the FTO gene and miRs show how they associate to obesity and how they can impact this disease. The aim of this study was to verify the relationship between the FTO gene and the hsa-miR-150-5p expression with overweight/obesity, lipid profile, and fast blood glucose.
View Article and Find Full Text PDFCo-contraction training has demonstrated similar electromyographic (EMG) activity levels compared to conventional strength training. Since verbal instructions can increase EMG activity on target muscles during conventional exercises, the same should occur during co-contraction. In this study we analyzed whether different verbal instructions would alter the EMG activity of target muscles - biceps brachii (BB) and triceps brachii lateral head (TB) - during co-contraction training for the elbow joint.
View Article and Find Full Text PDFThe ability to increase muscle strength seems to be influenced by extrinsic factors such as the characteristics of an exercise environment. Given that many people train while listening to music, the music environment is an important research topic. However, no studies have investigated whether a preferred music genre differentially affects strength production when compared to a non-preferred music genre.
View Article and Find Full Text PDFVerbal instruction increases electromyographic (EMG) activity in the first three repetitions of an exercise, but its effect on an entire exercise set until failure is unknown. Once there are changes in motor unit recruitment due to fatigue, the effect of verbal instructions can change during different intervals of a set. This study analyzed whether verbal instruction emphasized the contraction of back muscles (i.
View Article and Find Full Text PDFBackground: Previous studies reported a relationship between postural sway and force variability of the plantar flexor muscles (PFM), such that less force variability related to lower postural sway; however, this association does not seem to exist in older adults.
Research Question: This study investigated the effect of force stability training of the PFM on force variability (FV) of these muscles and postural sway in female older adults.
Methods: Thirty female older adults were divided into three groups: TG5 (n = 10), who trained at 5% of maximum voluntary isometric contraction (MVIC) of the PFM; TG10 (n = 10), who trained at 10 % of MVIC of the PFM; and CG (n = 10) who did not perform any specific training for the PFM.
Adnexal torsion is characterized by partial or complete rotation of the suspensory ligament of the ovary and its corresponding vascular pedicle, resulting in vascular impairment that can culminate in hemorrhagic infarction, as well as necrosis of the ovary and fallopian tube. Because there are myriad causes of acute pelvic pain, the differential diagnosis of ovarian torsion is often challenging. Consequently, radiologists should be familiar with the main imaging findings.
View Article and Find Full Text PDFThe force variability of the plantar flexor muscles (PFM) appears to be directly related to the control of upright standing. Nevertheless, this association is still uncertain in older adults. This study aimed to evaluate the relationship between PFM force variability and postural sway in the upright standing in older women.
View Article and Find Full Text PDFBackground: Obesity causes secondary hypogonadism (HG) in men. Standard testosterone (T) replacement therapy improves metabolic parameters but leads to infertility.
Objective: To evaluate clomiphene citrate (CC) treatment of adult men with male obesity-associated secondary hypogonadism (MOSH).
Identifying the trajectory and spin of the ball with speed and accuracy is critical for good performance in table tennis. The aim of this study was to analyze the ability of table tennis players presenting different levels of training/experience to identify the magnitude of the ball spin from the sound produced when the racket hit the ball. Four types of "forehand" contact sounds were collected in the laboratory, defined as: Fast Spin (spinning ball forward at 140 r/s); Medium Spin (105 r/s); Slow Spin (84 r/s); and Flat Hit (less than 60 r/s).
View Article and Find Full Text PDFBackground: Prior studies suggest that infants with Down syndrome (DS) need more experience to acquire a similar relationship between visual information and body sway than infants without DS. However, it is unclear how adults with DS deal with visual information to control posture.
Aim: To examine the coupling between visual information and body sway in adults with DS.
Background: muscle strength and power are two factors affecting balance. The impact of muscle strength and power on postural control has not been fully explored among different age strata over sixty.
Objectives: the aim of the present study was to assess the muscle strength and power of elderly women in different age groups and determine their correlation with postural control.
Objective: To assess the balance in dynamic tasks and in the quality of life in elderly women with and without knee osteoarthritis.
Methods: Elderly women were divided into Group 1 (n = 12), consisting of participants with bilateral knee osteoarthritis (Kellgreen-Lawrence grade 1 and 2), and Group 2 (n = 12), consisting of controls. A force plate (EMG System do Brazil) was used to assess postural sway in dynamic tasks, whereas the quality of life was assessed by using the WHOQOL-Bref questionnaire.
Background Context: Scoliosis is the most common postural alteration in adolescence and is characterized by deviations of the spine in three planes. Surgical treatment based on arthrodesis has been developed, but the effects of such restructuring on the systems involved in postural control need to be better understood.
Purpose: To assess the influence of vision and the support base on balance in the quiet standing position in adolescents awaiting surgical treatment for idiopathic scoliosis.
Objectives: To compare stabilometric parameters of elderly female fallers and non-fallers associated or not with knee osteoarthritis (OA).
Methods: Fifty-six elderly female fallers and non-fallers diagnosed or not with unilateral or bilateral knee OA were divided into the following groups: FOA (n = 10), elderly female fallers with knee OA; FNOA (n = 11), elderly female fallers without knee OA; NFOA (n = 14), elderly female non-fallers with knee OA; and NFNOA (n = 21), elderly female non-fallers without knee OA. For analyzing semi-static balance on a force platform with the elderly females standing, the following parameters were assessed in four conditions: center of pressure (COP), anterior-posterior and mediolateral displacements (APD and MLD, respectively); and COP anterior-posterior and mediolateral displacement velocities (APV and MLV, respectively).
Purpose: To evaluate the effect of surgical treatment on the control of upright balance in adolescent idiopathic scoliosis (AIS).
Methods: Thirty adolescents were divided into two groups: Group C (n=15) consisted of individuals without scoliosis (control), and Group S (n=15) consisted of individuals with scoliosis. The mean amplitude and velocity of the center of pressure (COP) evaluations in the anterior-posterior and medial-lateral directions were obtained before surgery and at 7, 30, 60 and 90-days after surgery, in an upright position, using a force platform.