OBJECTIVE Systemic sclerosis-associated pulmonary arterial hypertension differs from idiopathic pulmonary arterial hypertension with respect to histopathology, treatment responses and survival. Medical progress on PAH is hampered by the lack of human biosamples and suitable animal models. In this study, the authors evaluated fos-related antigen 2 (Fra-2) transgenic mice as a novel model for sys...

CONTEXT Elbow injuries are widely reported among baseball players. The elbow is susceptible to injury when elbow-flexor and -extensor forces are imbalanced during pitching or throwing. Assessment of muscle-strength ratios may prove useful for diagnosing elbow injury. OBJECTIVE The purpose of this study was to assess the relationship between the elbow-flexor and -extensor functional isokinetic...

OBJECTIVE To determine whether muscle strength in patients scheduled for total knee arthroplasty is: (i) strongly associated with both measured functional performance and patient-reported measures; (ii) more closely associated with functional performance when measured during concentric than during isometric contractions; and (iii) more strongly related to the 30-s chair stand test than to the t...

OBJECTIVE To determine the reliability of the Cybex 6000 isokinetic dynamometer in measuring the knee muscle performance concentrically and eccentrically. METHODS 18 male and 12 female subjects with no previous knee injuries, who had not previously undergone any isokinetic testing, were studied. The flexor and extensor muscles groups of both knees were tested at 60 degrees s-1 and 120 degrees...

The concentric and eccentric strength profile and muscular balance of the hip joint are important parameters for success in soccer. This study evaluated the reliability for the assessment of hip abduction and adduction isokinetic strength over a range of angular velocities (30 and 90°/s) and types of muscular actions (concentric and eccentric) in young soccer players. The reliability for the as...

Electromechanical efficiency (efficiencyE-M) has been used to detect changes in neuromuscular function and track decreases in torque production as a result of muscle fatigue. No previous investigations, however, have applied efficiencyEM to examine gender-specific decreases in torque as a result of fatigue. Therefore, the purpose of the present investigation was to examine gender differences in...

The purpose of this study was to estimate the efficiency of ATP utilization for concentric, eccentric, and isometric muscle action in the human tibialis anterior and extensor digitorum longus in vivo. A dynamometer was used to quantitate muscle work, or tension, while simultaneous 31P-nuclear magnetic resonance data were collected to monitor ATP, phosphocreatine, inorganic phosphate, and pH. Th...

Background: Electromyographic (EMG) and mechanomyographic (MMG) studies of fatigue have generally utilized maximal isometric or dynamic muscle actions, but sportand work-related activities involve predominately submaximal movements. Therefore, the purpose of the present investigation was to examine the torque, EMG, and MMG responses as a result of submaximal, concentric, isokinetic, forearm fle...

The force exerted by a muscle is a function of the activation level and the maximum (tetanic) muscle force. In "maximum" voluntary knee extensions muscle activation is lower for eccentric muscle velocities than for concentric velocities. The aim of this study was to model this "differential activation" in order to calculate the maximum voluntary knee extensor torque as a function of knee angula...

BACKGROUND AND OBJECTIVES Osteitis pubis refers to a painful, inflammatory condition involving the pubic bones, pubic symphysis, and adjacent structures. So, the aims of the study were to evaluate the strength of trunk muscles of soccer players suffering from osteitis pubis, and to compare the agonist/antagonist ratio of trunk muscles in osteitis pubis athletes with that of healthy athletes. ...