Considering the great popularity of eccentric-based training, the purpose of this review is to first provide the scientific rationale for its use; second, summarize the eccentric-based training modalities that can be used; and finally, offer practical recommendations on how to implement eccentricbased modalities to enhance sports performance. The molecular and neural mechanisms underlying eccentric actions are partially distinct from those of concentric and isometric actions. During eccentric actions, theories suggest a strain-induced modulation of actin-myosin interactions at the crossbridge level, activation of structural protein titin, and winding of titin on actin. Eccentric acute physiological responses differ from concentric exercise responses, including variations in neuromuscular, metabolic, hormonal, and anabolic signaling. Eccentric training elicits greater improvements in muscle strength, power, and stretch-shortening cycle function compared with concentric-only or traditional resistance training. Therefore, eccentric-based training can lead to unique neuromuscular (e.g., improved coordination of motor units) and morphological (e.g., increased muscle fascicle length and enhanced distal cross-sectional area) adaptations that could play a key role in sport performance. Practitioners may implement eccentric exercises with external loads, fully eccentric-based exercises (e.g., Nordic hamstring curl), accentuated eccentric loading, flywheel resistance exercise, and plyometrics to develop specific physical adaptations in line with their goals. Eccentric work (e.g., for hamstrings) can be obtained during other exercises such as downhill running tasks, decelerations, and sprinting activities. Practitioners need to be aware that no single “silver bullet” training modality exists; consequently, practitioners should use a combination of eccentric-based training approaches with their athletes to obtain the desired adaptations.

This NSCA Coach article explores how combining strength and plyometric training can improve volleyball hitters’ vertical jump and power. Visit NSCA online to read more on athletic performance and sports science.

A client asks you about melatonin, are you prepared to answer? This article explores the efficacy and safety of supplemental melatonin as a sleep aid in adults.

A physical assessment continues to be one of the best ways to evaluate and measure physical preparedness and readiness of a military unit for job-related tasks and future missions. Tactical facilitators must consider multiple factors when developing testing protocols and programs, including leadership support, limited resources, and training cycle time constraints.

To maintain an NSCA certification, all certified individuals must complete a certain number of Continuing Education Units (CEUs), every three years. Earning CEUs mean certificants stay current on evolving knowledge and skills in the profession, and promote the ongoing competency of those certified.

This article discusses the limitations and risks involved with artificial intelligence, such as ChatGPT, as a tool for personal trainers.

This excerpt from NSCA’s Guide to Sport and Exercise Nutrition discusses the research surrounding the timing of hydration and its impact on sport performance for those participating in aerobic endurance exercise.

The National Strength and Conditioning Association (NSCA) Foundation is proud to announce the recipients of its 2025 Research, Coaching Advancement, and Equipment Grants.

This article discusses using the principle of specificity as an important component in tactical training programs to enhance performance, decrease injuries, and improve functional longevity of a tactical athlete.

Choose your path with new 2026 NSCA Performance Summits on March 28, 2026. Join us at one of four specialized strength and conditioning events across the U.S. and earn 0.8 CEUs.