RESULTS The forced expiratory volume in 1 s ( FEV(1 ) ) , the ratio of FEV(1 ) to forced vital capacity ( FVC ) and body mass index were positively associated with the proportion of type I fibres in COPD .
This review sheds new light on the relationship between skeletal muscle abnormalities and important hallmarks of the disease in severe COPD , and identifies absence of data in GOLD stages 1 - 2 .
This review also provides reference values on fibre type composition for diagnostic purpose s in COPD
BACKGROUND Skeletal muscle dysfunction is a common feature in chronic obstructive pulmonary disease ( COPD ) which is associated with intrinsic muscular abnormalities .
One of the most consistently reported alterations is a shift from fibre type I to II in the vastus lateralis of these patients .
Surprisingly , the relationship between this shift and the severity and phenotype of COPD remains unclear .
A study was conducted to determine whether vastus lateralis muscle fibre type proportions are associated with COPD disease severity and to provide reference values for the proportions of fibre types in the vastus lateralis in COPD .
Effects of testosterone and resistance training in men with chronic obstructive pulmonary disease.
Dysfunction of the muscles of ambulation contributes to exercise intolerance in chronic obstructive pulmonary disease ( COPD ) . Men with COPD have high prevalence of low testosterone levels , which may contribute to muscle weakness . We determined effects of testosterone supplementation ( 100 mg of testosterone enanthate injected weekly ) with or without resistance training ( 45 minutes three times weekly ) on body composition and muscle function in 47 men with COPD ( mean FEV(1 ) = 40 % predicted ) and low testosterone levels ( mean = 320 ng/dl ) . Subjects were r and omized to 10 weeks of placebo injections + no training , testosterone injections + no training , placebo injections + resistance training , or testosterone injections + resistance training . Testosterone injections yielded a mean increase of 271 ng/dl in the nadir serum testosterone concentration ( to the middle of the normal range for young men ) . The lean body mass ( by dual-energy X-ray absorptiometry ) increase averaged 2.3 kg with testosterone alone and 3.3 kg with combined testosterone and resistance training ( p < 0.001 ) . Increase in one-repetition maximum leg press strength averaged 17.2 % with testosterone alone , 17.4 % with resistance training alone , and 26.8 % with testosterone + resistance training ( p < 0.001 ) . Interventions were well tolerated with no abnormalities in safety measures . Further studies are required to determine long-term benefits of adding testosterone supplementation and resistance training to rehabilitative programs for carefully screened men with COPD and low testosterone levels
RESULTS The forced expiratory volume in 1 s ( FEV(1 ) ) , the ratio of FEV(1 ) to forced vital capacity ( FVC ) and body mass index were positively associated with the proportion of type I fibres in COPD .
This review sheds new light on the relationship between skeletal muscle abnormalities and important hallmarks of the disease in severe COPD , and identifies absence of data in GOLD stages 1 - 2 .
This review also provides reference values on fibre type composition for diagnostic purpose s in COPD
BACKGROUND Skeletal muscle dysfunction is a common feature in chronic obstructive pulmonary disease ( COPD ) which is associated with intrinsic muscular abnormalities .
One of the most consistently reported alterations is a shift from fibre type I to II in the vastus lateralis of these patients .
Surprisingly , the relationship between this shift and the severity and phenotype of COPD remains unclear .
A study was conducted to determine whether vastus lateralis muscle fibre type proportions are associated with COPD disease severity and to provide reference values for the proportions of fibre types in the vastus lateralis in COPD .