The focus in “Combs” is clearly in the runs as they are constantly doubling while the number of squats decreases by 20 repetitions. You should still manage wisely the first set of squats in order to keep your legs fresh for the runs left. After 120 squats, it will be a real challenge for your legs to run the final 1600m! You’ve got 35 minutes...3-2-1 Go!
Scaling: If the given variation is too hard for you, scale “Combs” by doing half the repetitions and distance.