Can J Diabetes 36 (2012) 269e274
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Canadian Journal of Diabetes journal homepage: www.canadianjournalofdiabetes.com
Original Research
Relationship between Low Muscle Strength and Metabolic Risk Factors in Obese Postmenopausal Women: A Pilot Study Sébastien Barbat-Artigas MSc a, Marie-Eve Filion BSc b, Marie-Eve Ringuet BSc b, Mylène Aubertin-Leheudre PhD b, c, d, Antony D. Karelis PhD b, c, d, * a
Département de Biologie, Université du Québec à Montréal, Montréal, Canada Département de Kinanthropologie, Université du Québec à Montréal, Montréal, Canada c Centre de Recherche de L’institut Universitaire de Gériatrie de Montréal, Montréal, Canada d Groupe de Recherche en Activité Physique Adaptée, Université du Québec à Montréal, Montréal, Canada b
a r t i c l e i n f o
a b s t r a c t
Article history: Received 17 April 2012 Received in revised form 24 July 2012 Accepted 1 August 2012
Objective: To examine the relationship between low muscle strength and the metabolic profile in obese postmenopausal women. Methods: Forty-seven obese postmenopausal women were recruited (age: 60 ! 5 y; body mass index: 34.1 ! 3.5 kg/m2). Obesity was defined as a fat mass % >40. Subjects were considered as having low muscle strength levels based on a cut-point of handgrip strength measurement of 40. Les sujettes ont été considérées comme ayant un niveau de force musculaire faible selon un seuil de mesure de la force au dynamomètre < 28,56 kg. Les critères d’évaluation étaient les mesures anthropométriques, la composition corporelle (DEXA : dual-energy x-ray absorptiometry qui signifie absorptiométrie à rayons X en double énergie), la force au dynamomètre et les facteurs de risque cardiométabolique (c.-à-d. le bilan lipidique, la sensibilité à l’insuline). Résultats : Aucune différence significative des mesures anthropométriques, de la composition corporelle et du profil métabolique n’a été observée entre les femmes ayant une force au dynamomètre, faible ou normale. Cependant, nous avons observé que l’insuline (p ¼ 0,049), le glucose (p ¼ 0,036) et le modèle d’évaluation homéostatique (p ¼ 0,048) étaient significativement plus faibles, et la sensibilité à l’insuline (indice de Matsuda), significativement plus élevée (p ¼ 0,042) chez les femmes ayant une faible force musculaire comparativement aux femmes ayant une force musculaire normale. Conclusion : Une faible force musculaire semble être associée à un meilleur profil insulinémique chez les femmes postménopausées obèses. ! 2012 Canadian Diabetes Association
* Address for correspondence: Antony D. Karelis, Département de kinanthropologie, Université du Québec à Montréal, Case postale 8888, succursale Centre-ville, Montréal, Québec H3C 3P8, Canada. E-mail address:
[email protected] (A.D. Karelis). 1499-2671/$ e see front matter ! 2012 Canadian Diabetes Association http://dx.doi.org/10.1016/j.jcjd.2012.08.001
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S. Barbat-Artigas et al. / Can J Diabetes 36 (2012) 269e274
Introduction As the prevalence of overweight and obesity dramatically continues to increase, weight gain has now become a public health issue. Accordingly, the prevalence of overweight and obese individuals has reached 60% and more in North American countries (1). Obesity has been shown to be associated with functional decline (2). Furthermore, obesity has been widely recognized as a predisposing factor to cardiovascular diseases (CVD) and the metabolic syndrome, particularly among postmenopausal women, mainly due to changes in body composition associated with menopause (3). As with the increased body fat, menopause has been shown to be associated with decreased muscle mass (3). Evidence tends to show that low muscle mass, also known as sarcopenia, is associated with physical disabilities (4), but neither with the risk of hospitalization (5) nor with mortality (6). Although it has been suggested that sarcopenia may contribute to metabolic complications and CVD (7,8), findings of an 8-year follow-up study question this hypothesis (9). In addition, individuals presenting both sarcopenia and obesity simultaneously have been classified as “sarcopenicobese.” Consequences of sarcopenic-obesity on physical function appear to be conflicting (10). However, there is evidence to indicate that sarcopenic-obesity has no particular deleterious impact on metabolic risk factors and CVD (9,11,12). Along with the loss of muscle mass, an age-associated loss of muscle strength may be observed (13). Low muscle strength has been shown to be associated with poor cardio-respiratory functions (14), a decline in mobility (4,15), incident disability (16) and mortality (6,17). Moreover, low muscle strength may also be associated with an unfavorable metabolic risk profile. Accordingly, Atlantis et al (8) observed that muscle strength was a strong independent protective factor of insulin sensitivity. Levinger et al (18) also found some evidence to suggest that having a high number of metabolic risk factors, even without symptomatic heart disease, may affect exercise capacity, muscle strength and the capacity to perform activities of daily living as well as the quality of life in women. When combined with obesity, low muscle strength has recently been shown to be associated with a more impaired physical function than low muscle strength or obesity alone (19). However, to our knowledge, no studies have investigated the metabolic profile in obese individuals with low muscle strength. Therefore, the purpose of the present study was to examine the relationship between muscle strength and metabolic risk factors in obese postmenopausal women. We hypothesized that obese women with low muscle strength would have an unfavorable metabolic profile compare to obese women with normal muscle strength.
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