Welcome to the intriguing world of the Swing Phase, which occupies about 40% of the entire gait cycle. This stage has a dual mission: ensuring the foot sails cleanly over the ground during mid-swing and priming the leg for the upcoming impact forces of the approaching ground contact.
Initial Swing
Our exploration begins with the initial swing phase, ushered in by the remarkable moment of 'toe-off.' Here, the foot's stored propulsive forces catapult the leg into its flight path. The toe-off also ushers in the mesmerizing 'Double Float Phase', a split second where, given enough momentum, both feet hover in mid-air. As running speed amps up, this airborne interlude elongates.
Article Index
Anatomical Structures
Motion Specific Release
Conclusion & References
Key Anatomical Structures
Iliopsoas and Rectus Femoris (Hip Flexors):
The Iliopsoas and Rectus Femoris (Hip Flexors) are primarily responsible for hip flexion and pelvis stability during the initial swing phase, contributing to stride length and toe-off power. Dysfunction in these muscles can limit hip flexion, shorten stride length, reduce swing phase duration, and potentially disrupt running efficiency.
Visual Cues: Observations of a runner with a dysfunctional Iliopsoas or Rectus Femoris may include:
Reduced Stride and Swing: Due to limited hip flexion, the runner's stride length may be shortened, and the swing phase duration could decrease, affecting overall speed.
Compensation Patterns: The runner might overuse the contralateral leg, excessively tilt the pelvis, or lean the trunk to compensate for the lack of hip flexion. These movements can result in imbalances and increase injury risk.
Altered Foot Strike: The runner might adopt a more toe-oriented foot strike to offset decreased hip flexion, which can heighten stress on the foot and lower leg.
Lower Leg Swing: The foot may not rise significantly off the ground during the swing phase, leading to a tripping or stumbling risk.
Hamstrings:
Hamstrings, specifically Semitendinosus and Semimembranosus, are instrumental in the initial swing phase of the gait cycle, decelerating the thigh after hip extension and facilitating knee flexion to lift the foot. Hamstring dysfunction can impede leg acceleration and the swing phase force, potentially influencing running efficiency and stride length due to their fascial continuity with the sacrotuberous ligament and the gluteus maximus muscle.
Visual Cues: Observations of a runner with dysfunctional hamstrings during the initial swing phase may include:
Reduced Knee Flexion: A 'stiff-leg' gait pattern may emerge from decreased knee flexion, shortening the swing phase and stride length.
Increased Ground Contact: The runner's foot might have prolonged contact with the ground or drag due to insufficient foot lift, raising tripping or stumbling risks.
Compensation Patterns: Overuse of the hip flexors or quadriceps might occur to compensate for limited knee flexion, leading to muscle imbalances and possible injury risk.
Altered Running Efficiency: Hamstring dysfunction could affect overall running efficiency, leading to decreased performance and increased fatigue.
Posterior Thigh Discomfort: The runner might experience discomfort or tightness in the posterior thigh, which could further affect gait mechanics over time.
Visual Cues Check List
Iliopsoas and Rectus Femoris (Hip Flexors):
Shortened Stride: Noticeable decrease in stride length.
Pelvis/Torso Compensation: Excessive pelvic tilt or trunk lean.
Toe-Strike Emphasis: Predominant toe-oriented foot strike.
Low Foot Lift: Foot barely clears the ground, potential tripping hazard.
Hamstrings (Semitendinosus and Semimembranosus):
Stiff-Leg Gait: Reduced knee flexion, resulting in a 'stiff-leg' running pattern.
Ground Drag: Foot contact with the ground is prolonged or dragging.
Hip Flexor/Quadriceps Overuse: Excessive use of hip flexors or quadriceps.
Decreased Running Efficiency: Observable decrease in overall running speed or fluidity.
Posterior Thigh Discomfort: Signs of discomfort or tightness in the back of the thigh.
Motion Specific Release
MSR Demonstration
The Runner's Gait: Part 4 - Initial Swing Phase - The Swing Phase occupies about 40% of the entire gait cycle. This stage has a dual mission: ensuring the foot sails cleanly over the ground during mid-swing and priming the leg for the upcoming impact forces of the approaching ground contact.
Conclusion
In wrapping up, it's important to recognize that the initial swing phase of the gait cycle, constituting approximately 40% of the entire cycle, is a pivotal moment from a biomechanical standpoint. Initiated by toe-off, this phase has several objectives: to ensure adequate ground clearance by mid-swing and to prep the leg for the inevitable impact upon re-contacting the ground. The Hip Flexors, notably the Iliopsoas and Rectus Femoris, along with the hamstring muscles, are critical participants. Dysfunction in these hip flexors could have cascading consequences like diminished stride length and swing phase duration, subsequently affecting running efficiency. Among the symptomatic manifestations might be a reduced stride length, maladaptive movement strategies, altered foot strike, and a compromised leg swing.
Focusing on the hamstring muscles, specifically the Semitendinosus and Semimembranosus, their role isn't to be understated either. These muscles are instrumental in slowing down the thigh after the hip has extended and in facilitating knee flexion. Should these muscles not function optimally, they can act as a bottleneck in leg acceleration, truncating the swing phase and ultimately influencing stride length. As observable outcomes, a runner could face a range of issues such as reduced knee flexion, increased duration of ground contact, adoption of compensatory movement patterns, altered running efficiency, and discomfort in the posterior thigh. Understanding these nuances can be invaluable for refining running mechanics and forestalling injuries.
DR. BRIAN ABELSON DC. - The Author
Dr. Abelson's approach in musculoskeletal health care reflects a deep commitment to evidence-based practices and continuous learning. In his work at Kinetic Health in Calgary, Alberta, he focuses on integrating the latest research with a compassionate understanding of each patient's unique needs. As the developer of the Motion Specific Release (MSR) Treatment Systems, he views his role as both a practitioner and an educator, dedicated to sharing knowledge and techniques that can benefit the wider healthcare community. His ongoing efforts in teaching and practice aim to contribute positively to the field of musculoskeletal health, with a constant emphasis on patient-centered care and the collective advancement of treatment methods.
References
Novacheck, T. F. (1998). The biomechanics of running. Gait & Posture, 7(1), 77-95. doi:10.1016/S0966-6362(97)00038-6
Hamill, J., & Knutzen, K. M. (2009). Biomechanical basis of human movement. Lippincott Williams & Wilkins.
Cavanagh, P. R., & Lafortune, M. A. (1980). Ground reaction forces in distance running. Journal of Biomechanics, 13(5), 397-406. doi:10.1016/0021-9290(80)90033-0
Lieberman, D. E., Venkadesan, M., Werbel, W. A., Daoud, A. I., D'Andrea, S., Davis, I. S., Mang'eni, R. O., & Pitsiladis, Y. (2010). Foot strike patterns and collision forces in habitually barefoot versus shod runners. Nature, 463(7280), 531-535. doi:10.1038/nature08723
Mann, R., & Hagy, J. (1980). Biomechanics of walking, running, and sprinting. The American Journal of Sports Medicine, 8(5), 345-350. doi:10.1177/036354658000800506
Iosa, M., Fusco, A., Marchetti, F., Morone, G., Caltagirone, C., Paolucci, S., & Peppe, A. (2012). The golden ratio of gait harmony: repetitive proportions of repetitive gait phases. BioMed research international, 2012. doi:10.1155/2012/918642
Kerrigan, D. C., Todd, M. K., & Croce, U. D. (1998). Gender differences in joint biomechanics during walking: normative study in young adults. American Journal of Physical Medicine & Rehabilitation, 77(1), 2-7. doi:10.1097/00002060-199801000-00002
Taunton, J. E., Ryan, M. B., Clement, D. B., McKenzie, D. C., Lloyd-Smith, D. R., & Zumbo, B. D. (2002). A retrospective case-control analysis of 2002 running injuries. British journal of sports medicine, 36(2), 95-101. doi:10.1136/bjsm.36.2.95
Meardon, S. A., Hamill, J., & Derrick, T. R. (2011). Running injury and stride time variability over a prolonged run. Gait & posture, 33(1), 36-40. doi:10.1016/j.gaitpost.2010.10.009
Lieberman, D. E., Venkadesan, M., Werbel, W. A., Daoud, A. I., D'Andrea, S., Davis, I. S., ... & Pitsiladis, Y. (2010). Foot strike patterns and collision forces in habitually barefoot versus shod runners. Nature, 463(7280), 531-535. doi:10.1038/nature08723
Heiderscheit, B. C., Chumanov, E. S., Michalski, M. P., Wille, C. M., & Ryan, M. B. (2011). Effects of step rate manipulation on joint mechanics during running. Medicine & Science in Sports & Exercise, 43(2), 296-302. doi:10.1249/MSS.0b013e3181ebedf4
Novacheck, T. F. (1998). The biomechanics of running. Gait & Posture, 7(1), 77-95. doi:10.1016/S0966-6362(97)00038-6
Stearne, S. M., Alderson, J. A., Green, B. A., Donnelly, C. J., & Rubenson, J. (2016). Joint kinetics in rearfoot versus forefoot running: implications of switching technique. Medicine & Science in Sports & Exercise, 48(7), 1401-1410. doi:10.1249/MSS.0000000000000919
Hasegawa, H., Yamauchi, T., & Kraemer, W. J. (2007). Foot strike patterns of runners at the 15-km point during an elite-level half marathon. Journal of Strength and Conditioning Research, 21(3), 888-893. doi:10.1519/R-22096.1
Taunton, J. E., Ryan, M. B., Clement, D. B., McKenzie, D. C., Lloyd-Smith, D. R., & Zumbo, B. D. (2002). A retrospective case-control analysis of 2002 running injuries. British Journal of Sports Medicine, 36(2), 95-101. doi:10.1136/bjsm.36.2.95
Kerrigan, D. C., Franz, J. R., Keenan, G. S., Dicharry, J., Della Croce, U., & Wilder, R. P. (2009). The effect of running shoes on lower extremity joint torques. PM&R, 1(12), 1058-1063. doi:10.1016/j.pmrj.2009.09.011
Dierks, T. A., Manal, K. T., Hamill, J., & Davis, I. (2008). Proximal and distal influences on hip and knee kinematics in runners with patellofemoral pain during a prolonged run. Journal of Orthopaedic & Sports Physical Therapy, 38(8), 448-456. doi:10.2519/jospt.2008.2490
Zadpoor, A. A., & Nikooyan, A. A. (2011). The relationship between lower-extremity stress fractures and the ground reaction force: a systematic review. Clinical Biomechanics, 26(1), 23-28. doi:10.1016/j.clinbiomech.2010.08.005
Boyer, E. R., & Derrick, T. R. (2015). Select injury-related variables are affected by stride length and foot strike style during running. The American Journal of Sports Medicine, 43(9), 2310-2317. doi:10.1177/0363546515592837
Disclaimer:
The content on the MSR website, including articles and embedded videos, serves educational and informational purposes only. It is not a substitute for professional medical advice; only certified MSR practitioners should practice these techniques. By accessing this content, you assume full responsibility for your use of the information, acknowledging that the authors and contributors are not liable for any damages or claims that may arise.
This website does not establish a physician-patient relationship. If you have a medical concern, consult an appropriately licensed healthcare provider. Users under the age of 18 are not permitted to use the site. The MSR website may also feature links to third-party sites; however, we bear no responsibility for the content or practices of these external websites.
By using the MSR website, you agree to indemnify and hold the authors and contributors harmless from any claims, including legal fees, arising from your use of the site or violating these terms. This disclaimer constitutes part of the understanding between you and the website's authors regarding the use of the MSR website. For more information, read the full disclaimer and policies in this website.