Here are 2 running+core workouts you can do this week:

Aerobic workout
-All running at 80%

1) Repeat all 10x. Run at 80%. Rest 1 min after you finish
a. 50m run, turn around run 40m and walk the last 10; 2:1 recovery (however long it took you to run it, rest for double that time)
b. 100m run, turn and run 90, walk 10; 2:1 recovery
c. 100m run, 2:1 recovery

REST 1 MIN
2) Run at 100%. No recovery between runs
a. 50m and back
b. 100m and back
c. 50m and back

REST 5 MIN
3) Repeat (1) x5

REST 1 MIN
4) Repeat (2) x1

5) Core workout - Repeat x3
a. straight planks - 30-60sec hold
b. side plank - RIGHT - 30-60 sec
c. side plank - LEFT - 30-60 sec
d. 10-15 push ups
e. Glute/hip raise - 20

Workout #2

1) Repeat 6x (do everything 6 times). Run at 80%.

a. 50m and back; 2:1 recovery
b. 50m and back, 100m and back, 50m and back; 2:1 recovery
c. 100m and back; 2:1 recovery
d. 50. and back, 100m and back, 50m and back, 50m and back; 2:1 recovery

CORE/Bodyweight

REPEAT ALL 3x.
1. 30 jumping jacks
2. 30-60 sec mountain climbers
3. bear crawl for 20m
4. plank - straight, right, and left - hold for 30-60 sec
5. 25 sit ups
6. 10 push ups