The Investigation of Ground Reaction Forces to Validate Progression of Plyometric Exercise: A Pilot Study

Authors

• Bradley Bechard, Nova Southeastern UniversityFollow
• Brett Walker, Milwaukee BrewersFollow
• Peter Leno, Dickinson State UniversityFollow

Abstract

Purpose. Current approaches lack research toward rehabilitation of the lower extremity following injury regarding progression and the effects of ground reaction forces (GRFs) along the kinematic chain. A typical physical therapy protocol demonstrated the patients initially performing non-weight bearing, or open chain exercises followed by walking and running activities. This initial pilot study entertained the need for a more “seamless” progression of exercises to bridge the gap of GRFs when rehabilitating a weight bearing joint from walking-to-running in healthy individuals. Methods. 10 plyometric exercises were chosen for the study following careful review of evidence-based literature and researched protocols for strength and conditioning. Data was gathered from 11 physically active subjects. Subjects performed each plyometric exercise multiple trials while GRFs were recorded on a single force plate. Assessment was focused on the vertical GRFs for the dependent variable specifically. The vertical forces produced by each plyometric exercise were quantitatively rated in ascending order with a one-way ANOVA and paired t-test were performed between exercises and treadmill speeds. GRFs during walking and running for each participant were also gathered to investigate where the particular exercise fell in relationship to the values on a force plate treadmill. Results. Mean values for each plyometric exercise ranged from .93 x BW to 2.24 x BW. Conclusions. Based on the data that we measured and assessed, we conclude that the GRFs reported from this exploratory study appears the possibility that plyometric exercises represent a valid foundation which to further our investigation into exercise progression. A follow up study is warranted on injured or post-operative patients to assess the safety and effectiveness of plyometric rehabilitation progression. Additionally, further investigations justify the use of twin force plates to investigate individual lower extremity values during double limb landing.

Author Bio(s)

Bradley Bechard, PT, DPT, NCS, is the program director at the Great Falls College MSU Physical Therapist Assistant program in Great Falls, MT for the last 17 years. Brad is also currently completing his PhD at Nova Southeastern University in Physical Therapy.

Brett Walker, PT, DPT, ATC, SCS, MTC, is the rehabilitation coordinator for the Milwaukee Brewers in Phoenix, AZ and former director of rehab for the White Sox.

Peter J Leno, MS, CSCS, retired offensive line coach and kinesiology instructor for 30 years at Dickinson State University, ND. Peter is also vice president of operations for Treadmetrix, LLC.

Acknowledgements

ACKNOWLEDGEMENTS Authors Dr Bradley Bechard and Dr Brett Walker provided concept/idea/research design. Author Peter J Leno provided data collection and participants for this study. Dr Bechard provided writing of the manuscript while consultation (including review of the manuscript before submission) came from Dr Walker and Mr. Leno. Data analysis was provided by Dr Bechard and Dr Walker. Laboratory use and equipment was provided by Peter Leno at the Ben C. Frank Human Performance Center - Dickinson State University. Mr. Leno also provided institutional liaisons. Special thanks to Dr. Corey Peacock, PhD, CSCS, FISSN, Chair and Program Director at Nova Southeastern University, for his guidance and encouragement during the development of this manuscript.

Recommended Citation

Bechard B, Walker B, Leno P. The Investigation of Ground Reaction Forces to Validate Progression of Plyometric Exercise: A Pilot Study. The Internet Journal of Allied Health Sciences and Practice. 2026 Sep 01;24(3), Article 25.