RESUMO
CONTEXT: Traditional nonweight-bearing (NWB) hip-strength assessments may not directly translate to functional strength during weight-bearing (WB) activity. How NWB assessments of hip muscle strength compare with WB assessments in various positions is currently unknown. OBJECTIVE: To determine the magnitude of the differences and correlations between NWB hip strength and WB functional strength during the squatting and lunge (LNG) positions in female athletes. DESIGN: Crossover design. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: Female athletes (N = 51, age = 16.2 ± 3.5 years, height = 161.5 ± 8.3 cm, mass = 58.3 ± 11.6 kg). INTERVENTION(S): Isometric resistance (N/kg) was determined for the dominant and nondominant limbs via WB assessments (squat-bilateral [legs tested simultaneously], squat-unilateral, and lunge positions) and NWB assessments (hip external rotation [HER], hip extension [HEXT], and hip abduction [HAB]). MAIN OUTCOME MEASURE(S): To compare differences between positions (P ≤ .05), we used effect sizes (d) and matched-pairs t tests, and we calculated Pearson r and R2 values. RESULTS: During the squat-bilateral on the dominant limb, females produced the most hip torque (6.13 ± 1.12 N/kg). The magnitudes of differences were very large compared with HER (3.96 ± 0.83, d = 2.2), HEXT (3.22 ± 0.69, d = 3.2), and HAB (3.80 ± 1.01, d = 2.2; all P values ≤ .01), and positions were moderately correlated (r = 0.347-0.419, R2 = 0.12-0.18). The lunge position produced the least amount of torque in the dominant limb (2.44 ± 0.48 N/kg) compared with HER (d = -2.3), HEXT (d = -1.3), and HAB (d = -1.7; all P values ≤ .001), and correlations were small to moderate (r = 0.236-0.310, R2 = 0.06-0.10). CONCLUSIONS: Strength in WB positions was different than strength evaluated using traditional NWB assessments in female athletes. Weight-bearing tests may provide clinicians with additional information regarding strength and function.
