Table 1. Comparison of the differences in peak vertical force (PVF), plantar-flexion velocity (PFV), and Achilles tendon cross-sectional areas (AT CSA) in running on a downhill (-6%), level (0%), and uphill (+6%) grade. Data are means (±SD). Downhill Level Uphill Difference in AT CSA PrePost (cm2) -.028 (.025) -.025 (.024) -.019 (.034) Change (%) -7.14 -6.30 -4.87 PVF (BW) 2.72 (.20)* 2.52 (.16)* 2.37 (.13)* PFV (deg·s-1) 187.8 (.5)†  182.9 (.9)‡ 154.8 (.6) †  indicates significance from uphill running (p = 0.01). ‡ indicates significance from uphill running (p = 0.04) Difference in AT CSA PrePost: Difference in AT CSA from pre- to post-run. * indicates significance between grade conditions (p = 0.0001)