Isometric and isokinetic knee extension and flexion torque in men and women aged 20-70

Abstract

An investigation was made of the influence of age and sex on peak muscle torque in knee extension and flexion during maximal isokinetic and isometric contraction. The study was performed on both legs of 139 clinically healthy men and 141 clinically healthy women aged 20, 30, 40, 50, 60 or 70 years. Maximum knee extension and flexion muscle torque (Newtonmetre, Nm) was measured isokinetically at various angles of velocity (12, 90 and 150 degrees/s) and isometrically under standardized conditions (Cybex II). No significant differences were found between the right and the left leg in the whole material. Muscle torque was higher in men than in women in all age groups (p less than 0.001). Both isokinetic and isometric torque decreased with age in both sexes. Isokinetic torque decreased significantly (p less than 0.05) between 20 and 30 years of age in men and between 40 and 50 years of age in women (at all velocities studied; p less than 0.05). A significant decrease (p less than 0.05) was found between the ages of 60 and 70 years in both sexes. Maximum isometric torque showed a significant decrease (p less than 0.05) between 60 and 70 years in men and women. There were no significant differences in isokinetic or isometric torque between moderately active and inactive men or women. Significant correlations were found between muscle torque and body weight, height and body surface area.

Extension and flexion torque variability in ACL deficiency

“…Sjo ¨lander et al [22] showed that peripheral sensory inputs from ligament afferents participate in continuous control of muscle activity through feed-forward, or preprogramming, mechanisms. Moreover, poor neuromuscular control with weak ligament muscular reflexes and no muscular stretch reflexes is indicative of the ineffectiveness of the acute muscular reaction in providing early mechanical knee stabilization after injury [7]. It has also been suggested that ligament mechanoreceptors play an important role in muscle coordination and reflex regulation of functional joint stability.…”

“…As the healthy leg was the left leg in all subjects, the effect of ACL deficiency on knee extension and flexion may have been attenuated by decreased torque in the healthy leg. Borges [7] reported no significant differences in knee extension and flexion torques between the right and the left legs of healthy women and men aged 20–70 years.…”

Using Burst Modality Medium Frequency Alternating (Russian and Aussie) Currents with Isokinetic Training

“…Ghena et al [6] tested subjects at speeds up to 500°/sec. For the knee joint, velocities above 180°/sec are defined as high velocities [6,21]. The gain increase at high angular velocities and whether it provides meaningful data is controversial.…”

Frequency and Functional Consequences of Low Appendicular Lean Mass and Sarcopenic Obesity in Patients with Asthma Referred for Pulmonary Rehabilitation

“…The first step of the diagnosis level is based on altered skeletal muscle functional parameters considering strength. Patients with less than 80% of the predicted quadriceps peak torque as assessed by using a computerized dynamometer (Biodex System 4 Pro) were classified as presenting altered skeletal muscle function [21]. The next step, which is based on altered body composition, was confirmed in patients with increased FM and reduced muscle mass.…”

“…Endurance exercise capacity was measured by a submaximal constant work-rate cycle test (CWRT) at 75% of the pre-identified W max [28]. Isokinetic quadriceps muscle function was determined using a Biodex System 4 Pro (Biodex Medical Systems, Inc., NY, USA) [21]. Quadriceps muscle strength was defined as the highest peak torque (Nm), whereas isokinetic quadriceps muscle endurance was be defined as the total amount of delivered work (Joules) during a set of 30 repetitions.…”