i've got pretty decent at quickly making progress with these :p i now usually do 3-4 iterations now before having a finished run, i started off at high 48 pace here and had a 48.622 run before this one ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-SuLMd6jHxmI.html