When Do I Do HIIT

Bigger Stronger Leaner Competitive Bodybuilding
1

Right now I am training like this:
Day 1 - whole lower body 8-12 reps
Day 2 - whole upper body 8-12 reps
Day 3 - off
Day 4 - Whole lower body 5-8 reps
Day 5 - off
Day 6 - Whole upper body 5-8 reps
Day 7 - off

I do 20 minutes steady state cardio after the upper body workouts (days 2 and 6).

I want to do HIIT, but am not sure when the best day is to add it in.

Any suggestions?

Thanks in advance.

2

IMO on day 5 so it doesnt effect lower body w/o is best and maybe a PM session after the weights and a few meals

Phill