The relative effects of repetition, force and posture were studied in order to investigate how continuous biomechanical measurements can be combined into a single metric corresponding to subjective discomfort. A full factorial experiment was conducted involving repetitive wrist flexion from a neutral posture to a given angle against a controlled force. Seven subjects performed the task using tw...

Muscle reflexes, evoked by opposing a sudden joint displacement, may be modulated by several factors associated with the features of the mechanical perturbation. We investigated the variations of muscle reflex response in relation to the predictability of load magnitude during a reactive grasping task. Subjects were instructed to flex the fingers 2-5 very quickly after a stretching was exerted ...

BACKGROUND Osteoarthritis (OA) is a chronic disease, usually characterized by pain, which is associated with reduced muscle strength, disability and progressive loss of function. However, the pain influence over proprioception and motor behaviour remains unclear. Thus, the purpose of the study was to identify the levels of pain, the proprioceptive acuity and the pattern of muscle recruitment du...

The three rotations and three translations that comprise total knee motion were simultaneously measured in cadaveric knees during the commonly employed clinical tests for anterior cruciate injury. A second study determined the three-dimensional motions that occurred when known forces and moments were applied. A total of eight whole lower limbs were studied. A 6 degree-of-freedom instrumented li...

Purpose: Everything that impairs joint proprioception system can harm joints. It has been stated that stretching exercises can change properties of the proprioceptive receptors and as a result changes the sensibility of the joints proprioception. Due to fact that static stretching has greater use between athletes, it is necessary to give useful information about the safety of these stretch...

PURPOSE Previous long-term observational studies found that Tai Chi practitioners had better knee-joint proprioceptive acuity versus controls in an older population. We evaluated the effects of Tai Chi for knee-joint proprioception in knee osteoarthritis (OA) in a randomized controlled trial. METHODS We randomized 40 eligible individuals (age > 55, BMI ≤ 40 kg/m2 with knee pain on most days o...

CONTEXT Fatigue appears to influence musculoskeletal injury rates during athletic activities, but whether males and females respond differently to fatigue is unknown. OBJECTIVE To determine the influence of fatigue on vertical leg stiffness (K (VERT)) and muscle activation and joint movement strategies and whether healthy males and females respond similarly to fatigue. DESIGN Repeated-measu...

Tremor is described by Stein and Lee as an "involuntary movement characterized by a rhythmic oscillation about a fixed point or trajectory during activities controlled by the central nervous system." Among such oscillations are those demonstrated by healthy individuals and referred to as physiological tremors. These tremors are associated with posture or voluntary movement and are enhanced duri...