Baseline Assessments of Strength and Balance Performance and Bilateral Asymmetries in Collegiate Athletes

Dai, B, Layer, J, Vertz, C, Hinshaw, T, Cook, R, Li, Y, and Sha, Z. Baseline assessments of strength and balance performance and bilateral asymmetries in collegiate athletes. J Strength Cond Res 33(11): 3015-3029, 2019-Injuries to upper and lower extremities comprise more than 70% of the total injuries in collegiate athletes. Establishing normative data of upper and lower extremity strength and balance may help guide postinjury rehabilitation and return-to-play decisions. The purposes of the current study were to develop the normative data of performance and bilateral asymmetries during 4 upper and lower extremity strength and balance tests in collegiate athletes and to quantify the correlations between strength and balance performance and bilateral asymmetries. A total of 304 male and 195 female Division I athletes from 14 sports performed a maximum push-up test to assess upper extremity strength, a countermovement jump test to assess lower extremity strength, an upper extremity reaching test to assess upper extremity balance, and a lower extremity reaching test to assess lower extremity balance. Bilateral ground reaction forces were collected for the push-up and jump tests. Reaching distances were measured for the 2 balance tests. Bilateral asymmetries were generally less than 10%. Significant sports effects were observed for all 5 performance variables (p < 0.001) but not for asymmetry variables (p ≥ 0.36). Weak correlations were found between strength and balance performance and asymmetries (r < 0.3). Normative data are sex and sports specific in collegiate athletes. Increased asymmetries could be more individualized rather than sex and sports specific. When return-to-play decisions are made, athletes following injuries need to demonstrate less than 10% of asymmetries to be consistent with the normative data. Strength and balance should be evaluated and improved with specific focuses.