Zeglinksi C M, Swanson S C, Self B P, Greenwald R M
The Orthopedic Specialty Hospital, Salt Lake City, UT, USA.
Int J Sports Med. 1998 Oct;19(7):447-54. doi: 10.1055/s-2007-971943.
The electromyographic (EMG) activity of seven muscles of the trunk and lower extremity in five male masters level ski racers during a slalom turn in both alpine skiing and in-line skating was recorded using a telemetry system. Measurements were made on separate testing days using slopes commonly used in each activity (24 slope alpine skiing, 5 in-line skating). Qualitative video recorded at 60 Hz was analyzed to partition the turning cycle in both slalom skiing and in-line skating into initiation and turning phases. The EMG data from each turning cycle were normalized to standard isometric contractions (SIC's) for each muscle in order to quantitatively compare the amplitude characteristics of each phase of the turning cycle in both slalom skiing and in-line skating. The turning phase of in-line skating was found to be significantly longer (55%) than in slalom skiing, most likely due to significantly lower subject velocities recorded during in-line skating (8.5 m/s vs 10.2 m/s). All muscles were active at moderate to high levels (48-172% of SIC) during each phase of the turning cycle in both slalom skiing and in-line skating. The EMG amplitude characteristics were similar for six of the muscles in both slalom skiing and in-line skating for each of the turning phases. Only the erector spinae displayed significantly higher average and peak amplitudes in slalom skiing for both phases. It is concluded that the muscle activity patterns associated with the slalom turn of in-line skating are similar but notably more quasi-static than in slalom skiing.
使用遥测系统记录了5名男性大师级滑雪运动员在高山滑雪和轮滑回转转弯过程中躯干和下肢7块肌肉的肌电图（EMG）活动。在单独的测试日，使用每项活动常用的斜坡进行测量（高山滑雪24°斜坡，轮滑5°斜坡）。以60Hz录制的定性视频被分析，以将高山滑雪和轮滑回转转弯周期划分为起始阶段和转弯阶段。每个转弯周期的EMG数据针对每块肌肉进行标准化，以标准等长收缩（SIC）为基准，以便定量比较高山滑雪和轮滑转弯周期各阶段的幅度特征。结果发现，轮滑的转弯阶段明显长于高山滑雪（长55%），这很可能是因为轮滑过程中记录的受试者速度明显较低（8.5米/秒对10.2米/秒）。在高山滑雪和轮滑的转弯周期各阶段，所有肌肉均以中高水平（SIC的48%-172 %）活动。在每个转弯阶段，高山滑雪和轮滑中6块肌肉的EMG幅度特征相似。只有竖脊肌在两个阶段的高山滑雪中均显示出明显更高的平均幅度和峰值幅度。研究得出结论，与轮滑回转转弯相关的肌肉活动模式相似，但比高山滑雪明显更接近静态。
