Influence of Isometric and Dynamic Fatiguing Protocols on Dynamic Strength Index
Source abstract
Abstract
Background: Strength and conditioning experts widely recognize the dynamic strength index (DSI) as a tool for assessing an athlete’s ability to utilize strength in dynamic actions. The DSI is calculated as the ratio of peak force in dynamic actions versus isometric ones. To date, the influence of fatigue on the DSI is still not fully understood. This study aimed to explore the effects of both dynamic and isometric fatigue tasks on the DSI. Methods: A total of 24 physically active participants underwent fatigue tests involving repeated countermovement jumps (dynamic) and repeated isometric mid-thigh pulls (isometric) in separate visits. Results: The results revealed a marked drop in performance, with dynamic force showing a more significant reduction (p < 0.001; d = 1.57) than isometric force (p = 0.015; d = 0.30). After the isometric fatigue task, the DSI increased, indicating a more substantial decline in isometric force (p < 0.001; d = 1.75) compared to dynamic force (p = 0.313; d = 0.08). Following this trend, the DSI decreased post-dynamic fatigue (p < 0.001; d = 0.99) and increased post-isometric fatigue (p < 0.001; d = 3.11). Conclusion: This research underscores the need to consider fatigue’s task-specific effects on the DSI, enabling more tailored training methodologies for athletes.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Sports Performance and Training · Sports injuries and prevention · Lower Extremity Biomechanics and Pathologies
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Faculty of Health Sciences, University of Primorska, Polje 42, SI-6310 Izola, Slovenia
Human Health Department, InnoRenew CoE, Livade 6a, SI-6310 Izola, Slovenia
Ludwig Boltzmann Institute for Rehabilitation Research, Neugebäudeplatz 1, 3100 St. Pölten, Austria
Faculty of Sport Sciences, Department of Physical Education and Sport, University of Granada, 18012 Granada, Spain
Faculty of Education, Department of Sports Sciences and Physical Conditioning, Universidad Catolica de la Santísima Concepcion, Concepción 2850, Chile
Faculty of Sports Science, Ningbo University, Ningbo 315211, China
Research Academy of Human Biomechanics, The Affiliated Hospital of Medical School of Ningbo University, Ningbo University, Ningbo 315211, China
Funding
Slovenian Research Agency
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