Overview

This study is testing whether a new type of exercise program, called eccentric overload training using a flywheel device, can improve stair-climbing ability in people with knee osteoarthritis. The flywheel device provides resistance throughout the entire movement and gives extra challenge during the muscle-lengthening phase of exercise. This type of training may improve muscle structure, strength, and coordination more effectively than conventional methods.

The study's central idea is that better muscle quality and improved coordination will lead to smoother, safer stair movement and reduce the risk of falls. Advanced tools such as ultrasound imaging and motion analysis will be used to measure muscle health and movement patterns in detail.

The hypothesis is that individuals with knee osteoarthritis have poorer muscle quality and less coordinated stair-stepping compared to healthy adults, and that performing eccentric overload training will enhance muscle quality, improve movement coordination, and make stair navigation safer and more efficient.

Eligibility

Inclusion Criteria Osteoarthritis (OA) Group:

• Aged 40-70 years
• Radiographically confirmed knee OA (Kellgren-Lawrence \[KL\] Grade 2 or 3)
• Able to walk independently (assistive devices permitted)

Inclusion Criteria Healthy Control Group:

• Aged 40-70 years
• No radiographic evidence of knee OA (KL Grade 0 or 1)
• No frequent knee pain
• No history of:
• Knee surgery (e.g., ACL reconstruction, meniscectomy, patellar realignment)
• Significant knee injury (e.g., ligament tears, fractures, dislocations)
• Diagnosed knee conditions (e.g., patellofemoral pain syndrome, bursitis)

Exclusion Criteria:

• Uncontrolled hypertension or other cardiovascular disease
• A musculoskeletal condition preventing physical testing
• Neurological muscle weakness (e.g., stroke, spinal cord injury)
• BMI \>34.9 kg/m²
• Recent hospitalization (past 3 months)