ارتباط بین تغییرات قدرت هندگریپ با شاخص‌های گلایسمیک/ التهابی پس از یک دوره مداخله تمرینی در زنان سالمند مبتلا به دیابت نوع 2

Extended Abstract

Introduction: Aging is a complex and multifactorial process. The number of older adults has increased significantly over the past century, and the prevalence of type 2 diabetes mellitus among them has risen markedly in the last two decades. Furthermore, advancing age is associated with a reduction in muscle mass. Sarcopenia, characterized by reduced muscle strength and mass, is associated with type 2 diabetes mellitus. In addition to type 2 diabetes mellitus and aging, higher levels of pro-inflammatory cytokines are associated with sarcopenia. While aging itself leads to a decrease in muscle strength, particularly handgrip strength, tumor necrosis factor-alpha levels also increase with age and are higher in older adults with lower handgrip strength. On the other hand, exercise training generally reduces the incidence of type 2 diabetes mellitus in older adult. Both resistance and combined training improve body composition by reducing body mass index and lowering inflammatory factors such as tumor necrosis factor-α in older women. Resistance training is also associated with improved clinical status in terms of glycated hemoglobin levels   and muscle strength in older adults with type 2 diabetes mellitus and in postmenopausal women. Implementation of elastic band resistance training, as a simple, low-cost exercise program for older adults, and combined exercise training, respectively, leads to improvement in muscular strength, physical function, and metabolic status in older adults with type 2 diabetes mellitus.  Therefore, the aim of the present study was to investigate the relationship between changes in handgrip strength and changes in glycemic and inflammatory indicators in older women with type 2 diabetes mellitus following an elastic band resistance training and a combined training.

Methods: Twenty-six older women with type 2 diabetes mellitus (age: 72 ± 5.5 years; body mass index: 25.5±2) were selected from daycare department in the Kahrizak charity foundation care center, Iran and then randomly assigned to 12-week exercise training interventions: 1) elastic band resistance training group (medium intensity elastic band resistance training/thrice weekly/8 exercises/3 sets/10-15 reps/≈ 50 min; n = 13) and 2) combined training (a low intensity combined training ≈ 30 min; n = 13). Fasting serum levels of glycemic indices (insulin, glucose, glycated hemoglobin and insulin resistance), tumor necrosis factor-alpha, anthropometric indices (body weight and body mass index), and handgrip strength were measured using standard methods at baseline and 48 hours after the last session of interventions. Pearson/Spearman correlation coefficients (p ≤ 0.05) were used to determine the associations between the variables.

Results: A strong and significant inverse correlation was observed between changes in handgrip strength and tumor necrosis factor-alpha (r = -0.685, p = 0.002) in total participants (n = 26) (Figure 1) and a strong and a significant positive correlation was also observed between changes in handgrip strength and insulin resistance in elastic band resistance training group (r = 0.775, p = 0.04; n = 13), but no significant correlation was found between changes in handgrip strength and changes in fasting serum insulin, glucose, glycated hemoglobin, body weight and body mass index in any groups (p > 0.05).

Figure 1. Correlation between changes in Handgrip strength (HGS) and changes in tumor necrosis factor-α (TNF-α) in the total of elderly women with type 2 diabetes mellitus (n = 26)

Conclusion: Handgrip strength, as an indicator of muscular fitness, is associated with inflammatory status in older women with type 2 diabetes. Any exercise program capable of improving this index warrants consideration in the design of exercise protocols for elderly. Nevertheless, handgrip strength alone cannot serve as a suitable predictor for other aspects of health status, like glycemic status, in older women with type 2 diabetes. Probably other fitness components, such as cardiovascular fitness, also play a significant role in this regard which should be considered in future studies.

Footnotes:

Ethical approval: This study was approved and registered by the Research Ethic Committees of Kharazmi University of Tehran. Iran (IR.KHU.REC.1403.108) and by Iranian Registry of Clinical Trials (IRCT20241008063290N1).

Compliance with ethical guidelines: The research followed the ethical standards of the Declaration of Helsinki Ethical Principles for clinical research involving human subjects.

Funding: This work is based upon research funded by Iran National Science Foundation (INSF) under project No.4026206.

Authors’ contribution: Hamid Rajabi: Writing – review & editing, Writing - original draft, Supervision, Methodology, Conceptualization. Shokoufeh Kheradmand: Formal analysis, Conceptualization.

Conflict of interest: The authors declared no potential conflicts of interest relevant to this article.

Acknowledgments: The authors thank the participants of the study.