Dear editor
We read the valuable article of Oliveira et alCitation1 entitled “Resistance training improves isokinetic strength and metabolic syndrome-related phenotypes in postmenopausal women” with interest. In their well-designed prospective study, the authors observed improvement in metabolic syndrome-related phenotypes after 12 weeks of resistance training. We have some comments that could facilitate interpretation of the results of this study.
Because muscle mass is an important target for glucose uptake, sarcopenia seems to be an emerging risk factor for insulin resistance in elderly individuals.Citation2,Citation3 Resistance training is among the most important measures to attenuate sarcopenia.Citation4,Citation5 Thus, we suggest that there may be a close relationship between improvement in muscle mass and strength and reduction in insulin resistance in this study. At least some of the individuals in this study (90.3±24.1 Nm) seem to have sarcopenic muscle strength considering the muscle strength measurements of a sarcopenic obesity group (87.5±17.8 Nm) in a previous study from Brazil.Citation6 After the resistance training intervention, the muscle strength of the study population (101.9±21.4 Nm) is similar to the non-sarcopenic obese group (96±23.4 Nm) in the previous study. Thus, transition from sarcopenia to normal muscle mass and functions is a rational explanation to the improvement in insulin resistance in this study. We suggest that the authors assess the relationship between delta-homeostatic model assessment-insulin resistance (delta-HOMA-IR) and delta-muscle strength. Furthermore, a multivariate regression analysis might also be performed to seek independent factors underlying improvement of insulin resistance (delta-HOMA-IR). These analyses may provide clinically relevant information.
Disclosure
The authors report no conflicts of interest in this work.
References
- OliveiraPFGadelhaABGaucheRResistance training improves isokinetic strength and metabolic syndrome-related phenotypes in postmenopausal womenClin Interv Aging2015101299130426300634
- PerkisasSVandewoudeMWhere frailty meets diabetesDiabetes Metab Res Rev Epub2015109
- LeeSWYoumYLeeWJAppendicular skeletal muscle mass and insulin resistance in an elderly Korean population: the Korean social life, health and aging project-health examination cohortDiabetes Metab J2015391374525729711
- CsapoRAlegreLMEffects of resistance training with moderate vs heavy loads on muscle mass and strength in the elderly: a meta-analysisScand J Med Sci Sports Epub2015824
- Zembron-LacnyADziubekWRogowskiLSkorupkaEDabrowskaGSarcopenia: monitoring, molecular mechanisms, and physical interventionPhysiol Res201463668369125157651
- OliveiraRJBottaroMJuniorJTFarinattiPTBezerraLALimaRMIdentification of sarcopenic obesity in postmenopausal women: a cutoff proposalBraz J Med Biol Res201144111171117622002095