Effects of Periodized Circuit Training Versus Conventional Strength Training on Cardio metabolic and Pulmonary Outcomes in Type 2 Diabetes Mellitus: A Randomized Controlled Trial
Cardio-metabolic Adaptations to Exercise in T2DM
Keywords:
Exercise Therapy, Glycated Hemoglobin A, Pulmonary Function Tests, Resistance Training, Type-2 Diabetes MellitusAbstract
Background: Type 2 diabetes mellitus (T2DM) is associated with poor cardiovascular and metabolic outcomes. Although periodized circuit training (PCT) and conventional strength training (CST) are both recommended in the management of T2DM, the relative effectiveness of each training method across these multidimensional outcomes has not been clearly defined. Therefore, this study aimed to determine the effects of a 12-week PCT program with CST on pulmonary function, cardiovascular fitness, glycemic control, and Health related Quality of Life (HRQoL) in adults with T2DM.
Methods: Fifty adults with T2DM were randomly allocated to a PCT group (Group A, n=25) or a CST group (Group B, n=25) in a single-blind randomized controlled trial conducted at JPMC Hospital, Karachi. Both groups performed home-based training 3 times/week for 45-minute over 12 weeks. The baseline and post-intervention outcomes included FVC, FEV1, FEV1/FVC ratio, PEFR, six-minute walk test (6MWT) distance, HRQoL (SF-36), and HbA1c. Wilcoxon Signed-Rank and Mann–Whitney U were used for analysis.
Results: Both groups demonstrated important within-group improvement of most outcomes (p < 0.05). Between group analysis showed that there were no significant differences in FVC, FEV1, PEFR, 6MWT, HRQoL or HbA1c. Nevertheless, the FEV1/FVC ratio increased significantly in the PCT group compared to the CST group (83.52 ± 3.42% vs. 81.52 ± 2.85%; U=202.5, p=0.032), which is indicative of better airway efficiency.
Conclusion: Both PCT and CST are effective home-based interventions to improve pulmonary function, cardiovascular fitness, glycemic control and quality of life in T2DM patients. PCT demonstrated greater improvements in airway efficiency, suggesting broader pulmonary benefits.
DOI: https://doi.org/10.59564/amrj/04.02/002
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