<b><i>Background:</i></b> Diabetes as a metabolic disorder can affect the various systems of the body, resulting in a decrease in cardiovascular fitness, sleep quality, and life quality that can lead to depression and fatigue. <b><i>Aim:</i></b> We analyzed cardiovascular fitness, sleep quality, depression, fatigue, and quality of life among individuals with a glycated hemoglobin (HBA1C) level >6.5% and ≤6.5%, as well as the relationship among glycated hemoglobin, maximal oxygen consumption (VO<sub>2</sub>max), obesity, sleep quality, depression, and duration of diabetes. <b><i>Method:</i></b> HBA1C (mean: 5.90 ± 0.93%) was studied in a total of 70 subjects (mean age: 62.37 ± 7.5 years). The 2 study groups were as follows: group A, HBA1C >6.5%, and group B, HBA1C ≤6.5%. BMI, VO<sub>2</sub>max, quality of sleep and life, depression, and fatigue were assessed in both groups. <b><i>Results:</i></b> There was a statistically significant difference between the groups at a significance level of <i>p</i> < 0.001. Group A had a lower cardiovascular fitness, a poor sleep quality, and increased depression compared to group B. A statistically significant negative linear correlation was found between VO<sub>2</sub>max and glycated hemoglobin, and a significant positive linear correlation was found between glycated hemoglobin and duration of diabetes, poor quality of sleep, and depression for all subjects, which was insignificant in the groups. <b><i>Conclusions:</i></b> A long duration of diabetes and an increased glycemic status may influence cardiovascular fitness, sleep quality, and life quality, leading to depression and fatigue.