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Skeletal muscle properties and fatigue resistance in relation to smoking history.

Wüst RC, Morse CI, de Haan A, Rittweger J, Jones DA, Degens H - Eur. J. Appl. Physiol. (2008)

Bottom Line: Maximal strength and isometric contractile speed did not differ significantly between smokers and non-smokers.Muscle fatigue (measured as torque decline during a series of repetitive contractions) was greater in smokers (P = 0.014), but did not correlate with cigarette pack years (r = 0.094, P = 0.615), cigarettes smoked per day (r = 10.092, P = 0.628), respiratory function (%FEV(1pred)) (r = -0.187, P = 0.416), or physical activity level (r = -0.029, P = 0.877).An acute and reversible effect of smoking could be caused by carbon monoxide and/or other substances in smoke hampering oxygen delivery and mitochondrial function.

View Article: PubMed Central - PubMed

Affiliation: Institute for Biomedical Research into Human Movement and Health (IRM), Manchester Metropolitan University, John Dalton Building, Chester Street, Manchester, UK. r.wust@mmu.ac.uk

ABSTRACT
Although smoking-related diseases, such as chronic obstructive pulmonary disease (COPD), are often accompanied by increased peripheral muscle fatigability, the extent to which this is a feature of the disease or a direct effect of smoking per se is not known. Skeletal muscle function was investigated in terms of maximal voluntary isometric torque, activation, contractile properties and fatigability, using electrically evoked contractions of the quadriceps muscle of 40 smokers [19 men and 21 women; mean (SD) cigarette pack years: 9.9 (10.7)] and age- and physical activity level matched non-smokers (22 men and 23 women). Maximal strength and isometric contractile speed did not differ significantly between smokers and non-smokers. Muscle fatigue (measured as torque decline during a series of repetitive contractions) was greater in smokers (P = 0.014), but did not correlate with cigarette pack years (r = 0.094, P = 0.615), cigarettes smoked per day (r = 10.092, P = 0.628), respiratory function (%FEV(1pred)) (r = -0.187, P = 0.416), or physical activity level (r = -0.029, P = 0.877). While muscle mass and contractile properties are similar in smokers and non-smokers, smokers do suffer from greater peripheral muscle fatigue. The observation that the cigarette smoking history did not correlate with fatigability suggests that the effect is either acute and/or reaches a ceiling, rather than being cumulative. An acute and reversible effect of smoking could be caused by carbon monoxide and/or other substances in smoke hampering oxygen delivery and mitochondrial function.

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Maximal torque capacity, maximal voluntary torque corrected for voluntary activation (MTC) of the quadriceps muscle expressed as a function of age in male (a) and female (b) smokers and non-smokers. The decrease in maximal strength over time (and smoke exposure) was similar between smokers and non-smokers (NS)
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Fig1: Maximal torque capacity, maximal voluntary torque corrected for voluntary activation (MTC) of the quadriceps muscle expressed as a function of age in male (a) and female (b) smokers and non-smokers. The decrease in maximal strength over time (and smoke exposure) was similar between smokers and non-smokers (NS)

Mentions: The VA was higher in the smokers (Table 2). Maximal torque capacity (MVC corrected for VA; MTC) was lower in women than men (Table 2) and decreased in both men and women during ageing (Fig. 1). If we consider smoking or non-smoking there was no difference in MTC and ACSA (Table 2). However, stepwise linear regression showed that height, age, gender, physical activity level and years smoked significantly predict the ACSA (R2 = 0.793; P < 0.001), while cigarette pack years and cigarettes smoked per day did not improve the model.Fig. 1


Skeletal muscle properties and fatigue resistance in relation to smoking history.

Wüst RC, Morse CI, de Haan A, Rittweger J, Jones DA, Degens H - Eur. J. Appl. Physiol. (2008)

Maximal torque capacity, maximal voluntary torque corrected for voluntary activation (MTC) of the quadriceps muscle expressed as a function of age in male (a) and female (b) smokers and non-smokers. The decrease in maximal strength over time (and smoke exposure) was similar between smokers and non-smokers (NS)
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2480601&req=5

Fig1: Maximal torque capacity, maximal voluntary torque corrected for voluntary activation (MTC) of the quadriceps muscle expressed as a function of age in male (a) and female (b) smokers and non-smokers. The decrease in maximal strength over time (and smoke exposure) was similar between smokers and non-smokers (NS)
Mentions: The VA was higher in the smokers (Table 2). Maximal torque capacity (MVC corrected for VA; MTC) was lower in women than men (Table 2) and decreased in both men and women during ageing (Fig. 1). If we consider smoking or non-smoking there was no difference in MTC and ACSA (Table 2). However, stepwise linear regression showed that height, age, gender, physical activity level and years smoked significantly predict the ACSA (R2 = 0.793; P < 0.001), while cigarette pack years and cigarettes smoked per day did not improve the model.Fig. 1

Bottom Line: Maximal strength and isometric contractile speed did not differ significantly between smokers and non-smokers.Muscle fatigue (measured as torque decline during a series of repetitive contractions) was greater in smokers (P = 0.014), but did not correlate with cigarette pack years (r = 0.094, P = 0.615), cigarettes smoked per day (r = 10.092, P = 0.628), respiratory function (%FEV(1pred)) (r = -0.187, P = 0.416), or physical activity level (r = -0.029, P = 0.877).An acute and reversible effect of smoking could be caused by carbon monoxide and/or other substances in smoke hampering oxygen delivery and mitochondrial function.

View Article: PubMed Central - PubMed

Affiliation: Institute for Biomedical Research into Human Movement and Health (IRM), Manchester Metropolitan University, John Dalton Building, Chester Street, Manchester, UK. r.wust@mmu.ac.uk

ABSTRACT
Although smoking-related diseases, such as chronic obstructive pulmonary disease (COPD), are often accompanied by increased peripheral muscle fatigability, the extent to which this is a feature of the disease or a direct effect of smoking per se is not known. Skeletal muscle function was investigated in terms of maximal voluntary isometric torque, activation, contractile properties and fatigability, using electrically evoked contractions of the quadriceps muscle of 40 smokers [19 men and 21 women; mean (SD) cigarette pack years: 9.9 (10.7)] and age- and physical activity level matched non-smokers (22 men and 23 women). Maximal strength and isometric contractile speed did not differ significantly between smokers and non-smokers. Muscle fatigue (measured as torque decline during a series of repetitive contractions) was greater in smokers (P = 0.014), but did not correlate with cigarette pack years (r = 0.094, P = 0.615), cigarettes smoked per day (r = 10.092, P = 0.628), respiratory function (%FEV(1pred)) (r = -0.187, P = 0.416), or physical activity level (r = -0.029, P = 0.877). While muscle mass and contractile properties are similar in smokers and non-smokers, smokers do suffer from greater peripheral muscle fatigue. The observation that the cigarette smoking history did not correlate with fatigability suggests that the effect is either acute and/or reaches a ceiling, rather than being cumulative. An acute and reversible effect of smoking could be caused by carbon monoxide and/or other substances in smoke hampering oxygen delivery and mitochondrial function.

Show MeSH
Related in: MedlinePlus