Single-leg landing strategy after knee-joint cryotherapy

Context: Despite recent findings regarding lower extremity function after cryotherapy, little is known of the neuromuscular, kinetic, and kinematic changes that might occur during functional tasks. Objective: To evaluate changes in ground-reaction forces, muscle activity, and knee-joint flexion during single-leg landings after 20-minute knee-joint cryotherapy. Design: I x 4 repeated-measures, time-series design. Setting: Research laboratory. Patients or Other Participants: 20 healthy male and female subjects. Intervention: Subjects performed 5 single-leg landings before, immediately after, and 15 and 30 minutes after knee-joint cryotherapy. Main Outcome Measures: Ground-reaction force, knee-joint flexion, and muscle activity of the gastrocnemius, hamstrings, quadriceps, and gluteus medius. Results: Cryotherapy did not significantly (P > .05) change maximum knee-joint flexion, vertical ground-reaction force, or average muscle activity during a single-leg landing. Conclusion: Knee-joint cryotherapy might not place the lower extremity at risk for injury during landing.