29:48 It's a timed race they do every two weeks in the Docklands, organised by the local YMCA. pretty cool.
apparently my heart rate reached 196 at one point, guess that means my max HR is greater than 192! (as is calculated from 220-age)
given that my average HR was 181... if that was 90% then my max HR would be 201... if it was 85% my max would be 217 (!)... so it seems safe to say that that run really was as hard as it felt, and my max HR is around 200?