Effects of Simple Postural Instructions on Running Form Modification in Recreational Runners – Preliminary Findings

Abstract

Background and purpose: Running is one of the most popular exercises but it is also an activity with a high incidence of injury. Running form modification involving a forward lean of the trunk and forefoot strike pattern has been shown to be effective in attenuating the impact forces of the lower extremity. However, it is currently unknown how these changes can be most effectively instructed and learned by the runners. Previous studies have shown that practicing a motor task with an external focus can facilitate learning and retention when compared to the more common internal focus instructions. The purpose of this study is to examine the effectiveness of external and internal attentional focus cues on trunk posture and peak vertical ground reaction force (GRF) during the stance phase of running. Subjects and Methods: Ten recreational runners were selected for this study and randomly assigned tone of two groups receiving external or internal instructions designed to modify their running form. Trunk posture and GRF were obtained using a 3D motion capture system and a force plate instrumented treadmill while running at 2.5 m/s and a self-selected speed. Subjects were tested over a 5-week time period consisting of 4 sessions over a 4-week training program, followed by a final session 1 week after the training program to analyze retention of running form modification. Results: Overall there was a significant increase in trunk angle observed over time, following instruction, for both groups at speed 2.5 m/s. Running at speeds 2.5 m/s and a self-selected speed showed no statistically significant difference in increased trunk angle or GRF when comparing an internal versus external attentional focus. Conclusion: Simple postural instructions were shown to be effective for inducing greater trunk lean during running. This study found no difference in trunk angle or GRF when comparing internal and external attentional focus groups. Future studies would benefit from using clear and proper instructions that incorporate internal and external attentional focus cues with feedback to reinforce motor learning.