The Relationship of Walking and Running Speed Increment on Lower Extremities Joint Load Generated

Running is a popular type of physical activity among the community to improve their health and fitness. However, the highly repetitive stress due to increasing walking and running speed may cause lower extremities to suffer joint injuries. This research study was conducted to explore the relationship between speed increment and joint loads in the lower extremities during running. 15 healthy female subjects with normal BMI and aged between 20 to 25 years old were recruited into this study. Vertical ground reaction force (VGRF) was captured using the instrumented treadmill with embedded force plates. Additionally, the motion of lower extremities was analyzed using Kinovea software which enabled to study the participants’ running pattern. To determine the joint moments of lower extremities, the inverse dynamics technique and Newton-Euler equations were applied. The results revealed that as the walking speed increased, the peak ankle plantarflexion moment, peak knee flexion moment and peak knee extension moment during initial swing all significantly increased. Moreover, the peak ankle and knee joint moments during the stance phase have strong positive correlation with the running speed. Significant effect observed in the peak ankle plantarflexion at higher running speeds may attributed to a greater generation of propulsive force during running. The study provides valuable insights into how increasing running and walking speed impacts joint loads in healthy young women which can be useful for injury prevention strategies and optimizing sports performance.