Effect of exercise intensity on 6-keto-PGF1 alpha, TXB2, and 6-keto-PGF1 alpha/TXB2 ratios.

Six men (X = 27.3 yr) ran at 60%, 70% and 80% of maximal oxygen consumption on separate days for 30 minutes to determine exercise intensity effects on 6-keto-PGF1 alpha, TXB2, and 6-keto-PGF1 alpha/TXB2 ratios. At rest, 6-keto-PGF1 alpha was 384 +/- 68.3 pg/ml; TXB2 was 147 +/- 55.6 pg/ml; and the 6-keto-PGF1 alpha/TXB2 ratio was 4.63 +/- 1.3. After exercise at 60%, 70%, and 80% TXB2 increased to 523.2 +/- 117.5, 611.7 +/- 155.4*, and 643.8 +/- 121.7* pg/ml, respectively (*p less than .05). Post-exercise ratios tended to be inversely related to exercise intensity; however, no statistically significant differences were found between these values. These data suggest that exercise-induced increases in TXB2 may be related to intensity.