Type 2 Diabetes Mellitus and Downhill Aerobic Exercise Training

The purpose of this study is to compare the effects of an 8-week supervised downhill walking training program, prescribed based on the 6-minute walk test, on functional capacity, peripheral muscle strength, and cardiovascular responses in individuals with type 2 diabetes mellitus, as compared to a level walking training program. Participants who agree to take part in the study will be randomly assigned to either the downhill or the level-ground walking group. Both groups will undergo a 6-minute walk test (6MWT) at the beginning of the study, and participants will then undergo an 8-week walking training program-conducted twice a week on a treadmill under the supervision of a physical therapist-in which their walking speed is determined based on their average speed during the 6MWT and gradually increased, with the duration of the sessions also being extended. Participants will do the following: * They will participate in walking training sessions at a center twice a week for 8 weeks, under the supervision of a physical therapist. * Once a week for 8 weeks, they will walk the same distance they walked with their supervisor that week as a homework assignment. * They will come to the facility where they conducted their exercise sessions for evaluations at the beginning of the program and after the 8th week.

Inclusion Criteria: * Have been diagnosed with Type 2 diabetes mellitus according to the American Diabetes Association (ADA) diagnostic criteria * Be able to walk independently and be physically capable of walking on a treadmill * Have no acute cardiovascular, neurological, or orthopedic conditions that would prevent participation in the exercise program * No major changes to antidiabetic or cardiometabolic treatments within the last 3 months * To be under regular follow-up and in a stable clinical condition * To have been informed about the study and to provide written informed consent Exclusion Criteria: * Patients with severe peripheral neuropathy or a lack of protective sensation * Lower extremity amputation * Diabetic foot ulcer or the presence of severe skin lesions that impair walking * Proliferative diabetic retinopathy or advanced retinopathy that could pose a risk of complications during exercise * Severe diabetic nephropathy (eGFR \300 mg/g) * Uncontrolled hypertension (systolic blood pressure \>200 mmHg and/or diastolic blood pressure \>110 mmHg) * Fasting blood glucose level \>250 mg/dL with signs of ketosis * Unstable angina pectoris, a history of myocardial infarction within the past 6 months, or a history of clinically significant severe arrhythmia * Advanced heart failure (NYHA Class III-IV) * Having a chronic respiratory disease * Having participated in a regular exercise, sports, or physical therapy program within the past 6 months