against anteroposterior acceleration sway for 1s following landing (B). Hop landing ICC ranged from .673 to .929 indicating excellent to moderate reliability (Table 2 ). Dominant and nondominant medial hop landing had the greatest ICC, suggesting greater consistency in landing balance. Hop forward had
Jonathan M. Williams, Michael Gara and Carol Clark
Christina D. Davlin, William A. Sands and Barry B. Shultz
During a back tuck somersault, the angular velocity of the head is thought to surpass the visual system's ability to maintain a distinct and continuous picture of the environment. The primary objectives of this research were to determine if differences existed with regard to trunk and lower body kinematics, as well as landing balance, when gymnasts perform back tuck somersaults under different vision conditions. Ten female gymnasts (age = 11.6 ± 2.67 years, competitive level = 8 ± 1.15, and training time in gymnastics = 5.9 ± 1.63 years) performed back tuck somersaults under 4 vision conditions while wearing electromagnetic sensors that allowed automatic digitizing. Although no significant differences were found between vision conditions with regard to timing, joint angles, and joint angular velocities, gymnasts were more stable at landing under conditions that allowed vision during either the entire somersault or the last half of me somersault.
Marlene Luis and Luc Tremblay
We aimed to determine if visual feedback use during aerial skills is more efficient at low angular head velocity (AHV; i.e., <350 deg/s) than at high AHV. Twelve experienced female acrobats performed 20 back tuck somersaults under four experimental conditions: full-vision (FV), vision at AHV below 350 deg/s (VBelow), vision at AHV above 350 deg/s (VAbove), and no-vision (NV). AHV was calculated in real time, and liquid crystal goggles were used to manipulate vision. Two gymnastics judges scored landing stability using a four-point scale. All vision conditions that allowed some vision yielded significantly better landing scores than in the NV condition. Furthermore, a nonparametric test revealed that VBelow yielded a better performance ranking than the FV condition. We conclude that visual feedback during a back tuck somersault is used for landing stability at all angular head velocities, but optimal feedback use occurs when there is retinal stability.
A. Paige Lane, Sergio L. Molina, DaShae A. Tolleson, Stephen J. Langendorfer, Jacqueline D. Goodway and David F. Stodden
landing task and could be a manifestation of a lack of balance. By landing with one foot before the other, jump distance is minimized. Children may adopt the one-footed landing as a way to improve their landing balance and postural recovery by increasing the base of support in the sagittal plane. An