Insulin Use and Respiratory Muscle Strength in Type 2 Diabetes

Respiratory Muscle Strength, Pulmonary Function, and Post-Exercise Recovery Responses According to Insulin Use in Individuals With Type 2 Diabetes Mellitus

This study compares breathing function, breathing muscle strength, and recovery after a walking test in adults with type 2 diabetes, based on whether they use insulin.

People with type 2 diabetes will be evaluated during a single study visit at Izmir Bakircay University. Participants will be grouped as either currently using insulin or not using insulin as part of their usual diabetes treatment. All participants will complete the same tests: a breathing test (spirometry), breathing muscle strength tests (maximal inspiratory and expiratory pressures), and a 6-minute walk test.

Before the walk test, immediately after the test, and 5 minutes after the test, recovery measures such as heart rate, oxygen saturation, blood pressure, and perceived shortness of breath and fatigue will be recorded. The goal is to understand whether insulin use is associated with differences in breathing and recovery responses in people with type 2 diabetes.

Inclusion Criteria:

• Age 40 to 70 years
• Diagnosis of type 2 diabetes mellitus for at least 1 year
• Receiving diabetes treatment (oral antidiabetic agents and/or insulin) for at least 6 months
• Stable metabolic status (HbA1c ≤ 10%)
• Independent ambulation
• Able to read and understand Turkish
• Provided written informed consent

Exclusion Criteria:

• Diagnosis of type 1 diabetes mellitus
• Active diabetic foot ulcer
• Acute respiratory tract infection or known chronic respiratory disease (e.g., COPD, asthma, interstitial lung disease)
• Cardiovascular disease history that may limit exercise testing (e.g., heart failure, uncontrolled hypertension, arrhythmia)
• Neurological disease, musculoskeletal problem, or balance disorder precluding participation in the exercise test
• Major surgery within the past 6 months
• Current cancer treatment or history of malignancy
• Cognitive impairment or psychiatric condition limiting cooperation
• Pregnancy or breastfeeding