Abstract
Navigating obstacles while walking is a critical daily activity that requires both precise coordination and balance control, which has significant implications for fall prevention and rehabilitation. PURPOSE: This study aimed to investigate the biomechanical and neuromuscular mechanisms that underlie balance strategies during normal and big step obstacle crossing. METHODS: Twelve healthy young adults (ages 20–24) performed leap-style crossovers of a 15 cm (5.90”) high, 45° angled obstacle under two conditions: normal and big steps. Participants ensured their dominant leg landed on a force plate, entering the single-limb support (SLS) phase for analysis. One-way repeated ANOVA was used for each variable to compare between the big step and normal step. RESULTS: Big steps required a significantly greater knee flexion angle (36.36° ± 18.82° vs. 27.10° ± 16.20°, p < 0.05), eccentric knee extensor power (18.70 ± 6.20 W/kg vs. 15.60 ± 6.94 W/kg, p < 0.05), and eccentric work (3.16 ± 3.27 J/kg vs. 1.99 ± 1.25 J/kg, p < 0.05). Joint coordination was less synchronized during big steps and had a longer lag for the relationship between the ankle and knee (0.13 ± 0.18 s vs. 0.05 ± 0.02 s, p < 0.05) as well as the knee and hip (0.28 ± 0.25 s vs. 0.17 ± 0.18 s, p < 0.05). Additionally, knee-hip movements were opposite in direction for big steps (knee forward, hip backward), this contrasted from the synchronized forward movement observed in normal steps. Relative muscle contributions increased significantly in big steps, with greater activation of the quadriceps (21.37% ± 7.13% vs. 17.61% ± 6.08%, p < 0.05) and gluteus medius (11.04% ± 3.77% vs. 9.50% ± 3.05%, p < 0.05). CONCLUSION: These findings emphasize the heightened stabilization demands required by big steps during obstacle crossing. The greater knee flexion and increased eccentric power and work suggest a stronger reliance on the knee extensors for shock absorption and balance recovery. Meanwhile, the reduced joint synchronization and the opposite knee-hip movement patterns highlight the challenge of maintaining dynamic stability during big steps. Increased activation of the gluteus medius during the big step had a critical role in hip stabilization, compensating for the reduced coordination between the knee and hip joints. These findings strongly support the inclusion of big step training in rehabilitation programs aimed at improving lower extremity function. By specifically targeting knee extensor eccentric control, hip abductor strength, and inter-joint coordination, rehabilitation can enhance functional mobility and reduce the risk of falls.
Recommended Citation
Biggerstaff, Carly R.; Wyatt, David; Nuner, Emery; Hermanns, Joshua; Cabrera, Daniel; and Sanaei Ardakani, Amirhossein
(2025)
"The Impact of Big Steps Obstacle Negotiation on Knee Extensor Control, Hip Abductor Activation, and Inter-joint Coordination: A Potential Rehabilitation Strategy,"
International Journal of Exercise Science: Conference Proceedings: Vol. 2:
Iss.
17, Article 31.
Available at:
https://digitalcommons.wku.edu/ijesab/vol2/iss17/31
