Morgan D, Martin P, Craib M, Caruso C, Clifton R, Hopewell R
Department of Exercise and Sport Science, University of North Carolina at Greensboro 27412.
J Appl Physiol (1985). 1994 Jul;77(1):245-51. doi: 10.1152/jappl.1994.77.1.245.
To assess whether distance runners displaying uneconomical freely chosen step lengths (FCSL) could be trained to shift FCSL toward a more optimal setting, six males and three females who exhibited uneconomical FCSL [mean optimal step length (OSL) = -9.81% of leg length from FCSL; mean change in oxygen uptake (VO2) (FCSL - OSL) = 1.46 ml.kg-1.min-1] comprised an experimental group that completed 15 treadmill sessions (30 min/day, 5 days/wk, 3 wk) of OSL training at individually determined running velocities (2.87-3.74 m/s). Training sessions featured alternating 5-min periods of combined audio and visual feedback matching OSL and no feedback. A control group of three subjects with uneconomical FCSL (2 males, 1 female) performed 3 wk of treadmill running without feedback. The extent of step length optimization was evaluated by comparing pre- and posttraining differences between FCSL and OSL and between pre- and posttraining VO2. Compared with the control group, the experimental group demonstrated a significantly (P < or = 0.05) greater relative shift in FCSL toward OSL and a marked reduction in FCSL VO2. Taken together, these results suggest that short-term audiovisual feedback training can be effective in optimizing step length and producing a decrease in aerobic demand among distance runners exhibiting uneconomical FCSL.
为了评估那些表现出不经济的自由选择步长（FCSL）的长跑运动员是否能够通过训练将FCSL转变为更优化的设置，六名男性和三名女性组成了一个实验组，他们表现出不经济的FCSL[平均最佳步长（OSL）比FCSL短腿长的9.81%；平均摄氧量（VO2）变化（FCSL - OSL）= 1.46毫升·千克-1·分钟-1]，该实验组以个体确定的跑步速度（2.87 - 3.74米/秒）完成了15次跑步机训练课程（每天30分钟，每周5天，共3周）的OSL训练。训练课程包括交替进行5分钟的结合音频和视觉反馈以匹配OSL的时段和无反馈时段。一个由三名FCSL不经济的受试者（2名男性，1名女性）组成的对照组进行了3周无反馈的跑步机跑步。通过比较训练前后FCSL与OSL之间以及训练前后VO2之间的差异来评估步长优化的程度。与对照组相比，实验组在FCSL向OSL的相对转变上显著（P≤0.05）更大，并且FCSL的VO2显著降低。综上所述，这些结果表明，短期视听反馈训练对于优化步长以及降低表现出不经济FCSL的长跑运动员的有氧需求是有效的。
