Scatter plots between average and individual SLs in an LV myocyte of a mouse with normal systolic function. Data from M1 in Fig. 1 A during six cardiac cycles are shown for sarcomere nos. 1–30 (79 plots for each sarcomere). Sarcomere number is shown on top of each graph. X axis, average SL (average length of 30 sarcomeres); y axis, individual SL. Number in graph indicates CI for each sarcomere (i.e., R between average and individual SLs).