No evidence exists that repeated isolated quadriceps contractions lead to increased sagittal plane tibial translation. The purpose was to analyze passive and dynamic tibial translation before, during and after a specific exercise session, including cycling and a maximum number of knee extensions and heel-raises, in healthy individuals. Passive and dynamic sagittal tibial translation was measured on 18 healthy individuals (nine men and nine women) before, during and after a specific exercise session with heavy load, including cycling and maximum number of knee extensions and heel-raises. Sagittal tibial translation during the Lachman test, maximal isometric quadriceps contraction, one-legged squat and gait was registered with the CA-4000 electrogoniometer. The electromyographic (EMG) activity of m. vastus medialis and lateralis, m. gastrocnemius and mm. hamstrings was registered. There was no difference in passive or dynamic sagittal tibial translation during or after the exercise session. No difference could be detected in EMG activity during squat after compared with before the exercise session. In conclusion, the knee exercises did not influence the amount of translation in healthy individuals. The findings indicate that isolated strength training of quadriceps may be included in anterior cruciate ligament rehabilitation programs, even if further specific studies on injured individuals most be performed.
Comment In: Scand J Med Sci Sports. 2005 Jun;15(3):137-815885033