Pre-Race Caps have been my go-to supplement for long training runs, races and long adventure runs for years now. They give me so much stamina and endurance. I'm like the energizer bunny and I just watch people around me fade. I took them when I won the Leadville 100 in 2009 and 2011. I took them when I ran the R2R2R. I take them for extra long nordic ski outings. I take them for most long training runs and notice a huge difference when I take them and when I don't . I hesitate to write this review because they have been my "secret weapon" for racing, but, I do want other runners to enjoy the amazing benefits. I cannot recommend these highly enough.