30 Days of HIIT is a no-equipment interval program built on one simple currency: short bursts of all-out effort, paid daily. Every workout comes with three levels - typically 3, 5 or 7 sets on cardio days and scaled set counts everywhere else - so the same card serves a first-timer and a veteran, and the program you run this month can be re-run harder next month. All you need is a timer, some floor space and the willingness to go flat out for seconds at a time.
The month rotates through five kinds of days. Cardio HIIT circuits chain three or four exercises into a minute of continuous work per set. Single-exercise ladder days take one movement - a plank hold, climbers, high knees, half jacks - and run it through work and rest ladders that grow week by week, from ten-second bursts at the start to a full unbroken minute by Day 25. Active plank days keep you moving on your hands, plank sequences flow through five positions with no rest at all, and ab days complete the pattern with focused core circuits. There are no rest days: recovery is built into the rotation itself, with lighter formats following heavier ones so you can train every single day.
Effort here is personal: flat out means your flat out, and as long as you hold nothing back, every session counts regardless of your starting fitness. Expect better wind, quicker legs and a midsection that gets direct attention every third or fourth day, with most sessions fitting comfortably inside half an hour. When Day 30's final circuit is done, pick a higher level and go again - the card will be the same, and you won't be.
