Context:

Athletes are often examined for return to sports using a functional-testing algorithm. No research has determined whether a closed kinetic chain (CKC) isokinetic testing bout influences the reliability of functional tests.

Objective:

To determine whether a concentric CKC isokinetic test bout alters test–retest reliability of lower extremity functional testing.

Design:

Subjects participated in velocity-spectrum CKC isokinetic bouts on 2 days 1 week apart.

Setting:

Hospital-based clinic.

Participants:

28 normal subjects (mean age 26.7 years, height 27.2 cm, weight 75.8 kg).

Analysis and Results:

Means and SDs were determined. Intraclass correlation coefficients were used to calculate test–retest reliability and between days 1 and 2 ranged from .91 to .98.

Conclusions:

Even after a CKC isokinetic test bout, test–retest reliability of functional tests is very high. Future research should determine test–retest reliability of functional tests for patients with lower extremity pathology.