The effects of whole-body vibration therapy on type 2 diabetic patients with and without polyneuropathy

Diabetes mellitus (DM) is a chronic metabolic disease that leads to impairments in carbohydrate, protein, and fat metabolism due to deficiencies in insulin hormone secretion or action. The cornerstone of type 2 diabetes mellitus (T2DM) treatment includes medical therapy, diet, and exercise. Exercise not only helps improve glycemic control but also enhances physical endurance, improves quality of life, and reduces metabolic complications. The aim of this study is to investigate the effects of weighted whole-body vibration (WBV) exercises in T2DM patients with and without polyneuropathy and ground-based weighted exercises in T2DM patients without polyneuropathy on anthropometric parameters, flexibility, body composition analysis, visceral and abdominal fat measurements, muscle thickness measurements via ultrasound, functional parameters, quality of life, neuropathic pain, and levels of inflammatory molecules such as Fibroblast Growth Factor 21 (FGF-21), Interleukin-10 (IL-10), osteocalcin, adiponectin, Interleukin-6 (IL-6), Brain-Derived Neurotrophic Factor (BDNF), C-reactive protein (CRP), and myostatin. In this study, 22 patients with diabetic polyneuropathy (DPN) were included in the DPN (+) WBV group, while 46 patients without neuropathy were randomly assigned to the DPN (-) WBV and DPN (-) GROUND groups. Patients in the DPN (+) WBV and DPN (-) WBV groups underwent WBV exercise therapy three times per week for 12 weeks. The duration, number of sets, frequency, amplitude, and weights used in the exercises were progressively increased. Patients in the DPN (-) GROUND group performed the same exercises on a mat with similar durations, sets, and weights. Data obtained at the beginning and end of the 12-week exercise program were evaluated using the delta method. No statistically significant differences were found between the groups in terms of anthropometric measurements; body composition analysis results; ultrasonographic muscle thicknesses, except for forearm flexors between the DPN (-) WBV and DPN (-) GROUND groups; functional measurements, except for the 6-minute walk test (6MWT) between the DPN (+) WBV and DPN (-) GROUND groups; neuropathic pain scores; SF-36 quality of life parameters, except for mental health between the DPN (+) WBV and DPN (-) GROUND groups; and levels of inflammation-related biomarkers, including IL-10, osteocalcin, adiponectin, IL-6, BDNF, CRP, and myostatin, except for FGF-21. However, within-group comparisons revealed that weighted WBV exercises were effective in improving lower extremity muscle strength, reducing fat, enhancing physical endurance, improving balance performance, increasing quality of life, and reducing neuropathic pain in T2DM patients with and without neuropathy. Similarly, weighted mat-based exercises were effective in achieving these outcomes in T2DM patients without neuropathy. Despite these benefits, the exercises had no significant effect on inflammation-related biomarkers, except for FGF-21. In conclusion, weighted WBV exercises in T2DM patients with and without neuropathy, as well as weighted mat-based exercises in T2DM patients without neuropathy, were found to have similar effectiveness. The findings suggest that both approaches can serve as effective and safe methods, particularly for T2DM patients with limited exercise capacity.