Biomedical subjects

B E Grünig

Publications and source records attributed to B E Grünig.

4 recordsLinked to original sources

PubMed1989

Effect of thyroid dysfunction on thigh muscle efficiency.

To establish whether muscle weakness in thyroid dysfunction can be attributed solely to muscle atrophy (i.e. reduction in the total muscle cross-section) or whether the intrinsic contractile strength of the muscle is reduced per unit cross-sectional area, the ratio between thigh muscle strength and thigh muscle area was determined before and after treatment of hyper- and hypothyroidism. Midthigh muscle areas, assessed by computer tomography, increased in all seven hyperthyroid and decreased in three of four hypothyroid patients investigated after treatment of the thyroid disease. Peak torque and total work output, assessed by an isokinetic dynamometer (Cybex II), increased in both groups of patients. The muscle efficiency (total work output per cm2 muscle) increased in all patients after therapy [mean +/- SD values before vs. after therapy in hyperthyroid patients, 17.6 +/- 5.3 vs. 30.5 +/- 3.7 joules (J)/cm2 (P less than 0.001); in hypothyroid patients, 12.8 +/- 6.1 J/cm2 vs. 25.8 +/- 8.6 J/cm2 (P less than 0.05)]. Thus, the present study demonstrates that patients with thyroid dysfunction have altered muscle mass and diminished muscle efficiency.

Adult↗

PubMed1987

Impact of physical training on the ultrastructure of midthigh muscle in normal subjects and in patients treated with glucocorticoids.

Exercise-training might be a logical method to reverse muscle atrophy and weakness in patients treated with glucocorticoids. The purpose of the present investigation was to establish whether a treatment with low dose prednisone (10 +/- 2.9 mg/d) modulates the effect of a moderate strength type isokinetic training during 7 wk (21 sessions of 20 min) on "muscle efficiency" (power output/muscle mass) and on concomitant changes in ultrastructure of the thigh muscle measured by quantitative electron-microscopic morphometry. Training caused a similar increase in "muscle efficiency" in patients on prednisone (n = 9) as in normal volunteers (n = 9). In normal subjects the increase in muscle efficiency was associated with an increase in sarcoplasm, whereas in patients on prednisone the functional improvement was associated with an increase in sarcoplasm, capillaries, and mitochondria content. Thus, a therapy with low dose prednisone does not abrogate training-induced improvement of muscle efficiency but modulates the ultrastructural response of the muscle to the training.

Exercise Therapy↗

PubMed1985

Thigh muscle mass and function in patients treated with glucocorticoids.

Treatment with glucocorticoids causes wasting of proximal skeletal muscles. There is evidence that physical training improves muscle mass and strength in glucocorticoid-treated rats. Whether this is also true in humans is unknown. The present investigation was designed to establish in what respect moderate physical training may alter muscle mass and function as assessed quantitatively by computed tomography (CT) and with an isokinetic dynamometer (Cybex II). Compared with matched controls, both female (n = 17) and male (n = 22) patients treated with prednisone (15.4 +/- 6.6 mg die-1) had a lower mid-thigh muscle area of 20 and 45% and an increased mid-thigh fat/muscle ratio of 25 and 100%, respectively. The mean peak torque and the total work output of the thigh muscle were lower by 20-30% (n = 14). Fifty days of isokinetic training in six patients increased the thigh muscle area, decreased the thigh fat area and normalized the mean peak torque and total work output. Thus, glucocorticoid-induced muscle wasting can be reversed by increasing physical activity.

Adult↗

PubMed1985

Evidence that prednisone-induced myopathy is reversed by physical training.

Treatment with glucocorticoids causes wasting of proximal skeletal muscles. There is evidence that physical training improves muscle mass and strength in glucocorticoid-treated rats. Whether this is also true in humans is not known. The present investigation was designed to establish in what respect moderate physical training may alter muscle mass and function as assessed quantitatively by computed tomography (CT) and an isokinetic dynamometer (Cybex II). Compared with matched normal subjects (n = 12), patients (n = 12) treated with prednisone [12.6 +/- 3.3 (+/- SD) mg/day] had a 20% lower midthigh muscle area and a 36% increase in midthigh fat to muscle ratio. The mean peak torque and the total work output of the thigh muscle were lower by more than 20%. Baseline measurements of total work output or peak torque at all tested velocities increased with midthigh muscle area (r = 0.73; n = 24; P less than 0.001). Fifty days of isokinetic training in 12 patients increased the thigh muscle area, decreased the thigh fat area, and normalized the mean peak torque and total work output. The increase in peak torque was inversely correlated with the daily dose of prednisone (r = 0.60; n = 12; P less than 0.05). Thus, glucocorticoid-induced muscle wasting can be reversed by increasing physical activity in patients taking a low to moderate dose of prednisone.

Adult↗