Six women and 6 men trained the elbow flexors 3 days per week for 20 wks, one arm performing in each session 3-5 sets of 10 maximal concentric actions on an accommodating resistance device, the other arm 3 - 5 sets of 8 - 12 coupled eccentric/concentric actions on a weight training device. With results collapsed across the two training modes, the women made significantly (p < 0.05) greater relative increases than men in strength measured on the weight (116 vs. 46 %) and accommodating (99 vs. 46 %) resistance devices, and greater absolute (3.5 vs. - 1.3 N m) and relative (13.7 vs. - 3.2 %) increases in strength measured on an isokinetic dynamometer. Absolute (cm2) and relative ( %) biceps, brachialis, and total elbow flexor cross-sectional area (from CT scans) increased significantly; however, the women's vs. men's respective relative and absolute increases did not differ significantly: biceps (13 vs. 7 %, 0.9 vs. 1.0 cm2), brachialis (53 vs. 31 %, 2.1 vs. 2.3 cm2), and total (26 vs. 15 %, 3.1 vs. 3.3 cm2) flexor area. Biceps type I and II fiber area, and the ll/l area ratio did not increase significantly. The data indicate that in response to the same short-term training program, muscle size increases similarly in women and men but women make greater relative increases in strength.