Lying Pull-Ups and 3 K Run

This morning I went to a park near my house to do lying pull-ups on a playing castle for kids.
I did two sets of 36 reps (divided into four chunks of 12, 10, 8, and 6)
with a rest of 8 seconds between chunks, and one minute between sets.
Two sets are doable, though the last few reps of the last two chunks were tough.
I will carry on with this routine for a while.
When two sets become too easy, I will consider increasing the number of sets.

After that I hit the running track across the street and ran 3 K.
Today's result is as follows.

0~500 M: 2:40
500 M~1 K: 2:36
1~1.5 K: 2:32
1.5~2 K: 2:28
2~2.5 K: 2:25
2.5~3 K: 2:28