Videoendoscopic (VES) instruments have poor force transmission properties and often require surgeons to employ awkward hand and arm positions. In order to compare the physical workload of laparoscopic surgery to open surgery, we collected long-duration EMG records from the thumb (thenar compartment) of six surgeons perfonning suturing and knot tying in a training box using both open and VES techniques. EMG signals were acquired using a LabVTEW® Virtual Instrument and analyzed using a Modified Exposure Variation Analysis (MEVA) algorithm. Standard EMG indices and the MEVA analysis demonstrated significantly greater amplitude and duration of EMG signals using VES technique compared to open technique. Our results suggest that the use VES techniques requires a greater intensity of physical effort than open surgery techniques.