Is larger eccentric utilization ratio associated with poorer rate of force development in squat jump? An exploratory study

ABSTRACTThis exploratory study examines the relationship between the eccentric utilization ratio (EUR) and the rate of force development (RFD) in squat jumps (SJ). EUR, a key metric in sports science, compares performance in countermovement jumps (CMJ) and squat jumps (SJ). The study hypothesizes that a higher EUR is associated with a poorer RFD in SJ. Basketball and soccer players, long-distance runners, alongside physical education students (209 men; age: 23.2 ± 4.95 years and 104 women; age: 22.7 ± 4.42 years) participated. The EUR was calculated from jump height, peak force and peak power. The results indicated a small to moderate but significant negative correlation between EUR based on peak force or peak power and RFD in SJ (r = –.41 and −.27), suggesting that a higher EUR might be linked to a diminished ability to rapidly develop force in SJ. Thus, a higher EUR may not indicate superior athletic performance.