The Reliability of a Rotational Power Assessment of the Core

Context: Most athletic upper-body power generation involves high levels of neuromuscular activation/coordination of a rotational nature. Therefore, it is important to assess athletic ability that replicates the rotational activity of athletes. However, a paucity of research currently measures rotational power of the core. Objective: Establish inter-day reliability of chop and lift mean power output via a linear position transducer on rotational reliant power athletes. Design: Controlled laboratory study. Setting: Professional cricket training facilities. Population: Eight male professional cricket players (age= 23±3.38 years, height= 186±10.06 cm, mass= 89.71±8.12 kg) with a resistance (>2 years) training background volunteered to participate in the study. Intervention: A linear position transducer was attached to the weight stack of a cable pulley system to determine the peak power outputs associated with a chop and lift movement. Assessment occurred on three occasions separated by at least seven days.Asymmetry, intraclass correlation coefficients (ICCs) and coefficient of variations (CV) were calculated and used to quantify the absolute and relative consistency of the testing procedures. Results: The mean peak power outputs for chop and lift ranged from 404 - 494W and 277-314W respectively, the power outputs differing minimally (2.7-6.3%) between the left and right sides. Coefficients of variation of 7.4% - 19% were reported, with intraclass correlation coefficients of 0.54 - 0.94 observed between testing occasions. Conclusion: Mean muscular power output associated with the lift assessment reported greatest reliability in well trained athletes.The asymmetry between sides was relatively small suggesting balanced multi-planar trunk development in the current throwing athletes. Equipment limitations (load related), training status and variable selection (mean or peak power) need to be considered prior to rotational assessment of the core. It is recommended that the lift movement is utilized in rotational  power assessments, or that greater familiarization is undertaken when administering the chop assessment.