Intervals 17:25 [4] 4.8 km (3:38 / km)
(3 times 400 + 1200m) time 2, on a road loop of 1200m with about 2 mins rest between and 4 for the 1200 (slightly longer so the group could get on average full rest), so some slightly different times for the different parts for the 400m (first = flat, second = one short steep hill, third = slightly downhill).
1:21 - 400m
2:10 - rest
1:24 - 400m
2:01 - rest
1:22 - 400m
2:27 - rest
4:39 - 1200m
4:37 - rest
1:23 - 400m
2:00 - rest
1:24 - 400m
2:04 - rest
1:19 - 400m
2:23 - rest
4:33 - 1200m
Managed to keep the pace ok, despite increasing bowel issues (found the bushes quickly after)