This randomized controlled trial aims to investigate the effects of adding self-myofascial release applied to the plantar fascia and gastrosoleus muscles to an exercise program on foot function, physical performance, and plantar fascia thickness in individuals with type 2 diabetes. Participants aged 30 to 65 years with controlled type 2 diabetes will be randomly allocated to either an exercise-only group or an exercise plus self-myofascial release group. Both groups will complete an eight-week supervised exercise program three times per week. The intervention group will additionally perform self-myofascial release using a foam roller before exercise sessions. Outcomes will include foot function, balance, functional mobility, gait performance, and plantar fascia thickness assessed by ultrasonography before and after the intervention.

This randomized controlled trial will investigate the effects of adding self-myofascial release applied to the plantar fascia and gastrosoleus muscles to exercise therapy on foot function, physical performance, and plantar fascia thickness in individuals with type 2 diabetes. Individuals aged 30 to 65 years with controlled type 2 diabetes diagnosed for at least one year and able to ambulate independently without assistive devices will be included.

Participants will be randomly allocated into two groups. The exercise group will receive an eight-week exercise program, while the exercise plus self-myofascial release group will receive the same exercise program combined with self-myofascial release applied to the plantar fascia and gastrosoleus muscles.

The eight-week exercise program will include supervised general strengthening exercises targeting the upper and lower extremities, back, and core muscles, as well as stretching exercises for warm up and cool down, performed three times per week. In addition, participants will be advised to perform at least 150 minutes per week of moderate-intensity walking. Adherence will be supported with an informational brochure and monitored using an exercise diary.

Self-myofascial release will be applied using a foam roller three times per week for eight weeks before the exercise sessions.

Outcome measures will include the Foot Function Index, single-leg stance test with eyes open and closed, Timed Up and Go test, unilateral heel-rise test, Berg Balance Scale, and 10-meter walk test performed under single-task and dual-task conditions, including a cognitive task (verbal fluency using words starting with the letter "k") and a motor task (continuous head rotations paced at 40 beats per minute using a metronome). Plantar fascia thickness will be assessed by ultrasonography. All assessments will be conducted before and after the eight-week intervention.

Inclusion Criteria:

• Individuals aged 30 to 65 years
• Diagnosed with type 2 diabetes mellitus for at least 1 year
• Controlled type 2 diabetes mellitus
• Able to ambulate independently without assistive devices

Exclusion Criteria:

• Severe pes planus or pes cavus defined by the Foot Posture Index-6 (FPI-6) (score ≥ +10 or ≤ -5)
• History of plantar fasciitis
• Plantar fascia ulceration
• Peripheral neuropathy
• Diagnosed peripheral vascular disease
• History of lower extremity surgery or fracture during last year
• Rheumatologic or connective tissue disorders affecting soft tissue properties
• Neurological or diagnosed cognitive disorders
• Pregnancy
• Other types of diabetes mellitus
• Obesity (BMI > 30 kg/m²)
• Serious cardiopulmonary disorders, including heart failure, history of myocardial infarction, or severe chronic obstructive pulmonary disease or asthma

Data sharing plans have not yet been determined. De-identified individual participant data may be shared upon reasonable request following publication, subject to institutional and ethical approval.