Fatigue and oxidative stress response to physical activity in type 2 diabetic patients

Physical activity (PA) and exercise is known to have a positive impact on a variety of variables pertinent to diabetes and cardiovascular disease. The aims of this study were to investigate the effects of physical activity on fatigue scores, oxidative stress, and glycemic control variables of individuals with type 2 diabetes mellitus (T2DM). Seventy-five subjects diagnosed with T2DM for more than 5 years aged 18–65 years participated in this study. The participants classified according to energy expenditure into, physically inactive [≤500 metabolic equivalents (METs)-min/week, n = 25], moderate PA (500–2500 METs-min/week, n = 25), and PA (≥2500 METs-min/week, n = 25). The Global Physical Activity Questionnaire (GPAQ) version 2.0 was used to classify physical activity. The multidimensional checklist individual strength questionnaire (CIS20r) was used to measure chronic fatigue. Blood glucose was measured using a glucose oxidase and peroxidase (GOD-POD) colorimetric method. HbA1c was measured using a commercial kit. Serum insulin level was determined using an ELISA. Analysis of oxidative stress parameters including malonaldehyde (MDA) and total antioxidant capacity (TAC) was done. To test differences between severely fatigued and healthy subjects, an independent t test was performed. Spearman correlations were used to assess correlations between fatigue severity score and disease-related and psychosocial factors. A level of significance was set at p < 0.05. The results showed a significant reduction of fasting blood sugar, glycosylated hemoglobin, fasting insulin, and MDA along with significant increase in TAC activity in the participants with moderate PA (P < 0.05) and PA (P < 0.01), respectively. In relation to CIS-fatigue measurements, about 33 % of the study population (n = 25) had a CIS score above the cutoff score of 37 with 59.5 mean CIS score, and 67 % of the study population (n = 50) had CIS score below the cutoff 37; they were classified into heightened fatigue (score 27–35) and healthy (score ≤27). There was a significant correlation between the reduction of diabetic related variables, BMI, PA status, and CIS-fatigue score analyses in T2DM patients. CIS-fatigue scores correlated positively with diabetic related variables and negatively with PA, BMI, and TAC activity. PA plays a vital role in improving CIS-fatigue score in type 2 diabetic patients via reducing oxidative stress and diabetic related variables.