I got into HIIT because I hate running. Seriously - the thought of jogging for 45 minutes makes me want to stay on the couch. But 20 minutes of intervals? That I can do. And honestly, the results have been better than anything I got from traditional cardio.

The catch is that HIIT only works if you actually push during work intervals. Not "challenging but comfortable" - actual hard effort that you can't maintain for long. That's where most people (including past me) mess it up. They go through the motions instead of actually going hard.

What HIIT Actually Is

High-Intensity Interval Training alternates between bursts of hard effort and recovery periods. Simple concept, but the "high intensity" part matters more than people think. You should be at 80-95% of your max heart rate during work intervals.

A typical session runs 15-30 minutes. Research shows this can match or beat longer steady-state cardio for calorie burn and fitness gains. But I think the real advantage is psychological - knowing it's short makes it easier to actually do it.

Protocols I Actually Use

There are endless HIIT variations. Here are the ones I keep coming back to:

Tabata (20/10) - My finisher

20 seconds work, 10 seconds rest, 8 rounds = 4 minutes of suffering

I use this at the end of strength workouts. Four minutes and you're done.

Classic 30/30 - Where I started

30 seconds work, 30 seconds rest, 10-20 rounds

Equal work and rest makes this approachable. Start here if you're new.

40/20 - My current favorite

40 seconds work, 20 seconds rest, 8-12 rounds

Enough work time to get into a rhythm, short rest keeps intensity up.

EMOM - When I want variety

Complete exercises at the start of each minute, rest for remaining time

The faster you finish, the more rest you get. Naturally motivating.

What Your Timer Needs

I've tried phone apps, gym clocks, YouTube videos. Here's what actually matters:

Loud audio cues: You can't check your phone mid-burpee. You need to hear it.
Big visual countdown: Glanceable from across the room when you're dying on the floor.
Custom intervals: Not every workout is 30/30. Your timer should adapt.
Round counter: Because you will lose count. Trust me.
Prep countdown: A few seconds warning before work starts so you're ready.

Work-to-Rest Ratios: How to Pick

The ratio determines how hard the workout feels. More rest = easier to sustain intensity. Less rest = brutal. Here's my honest assessment:

Ratio	Feel	My Take
1:3 (15s/45s)	Manageable	Start here if you're new or coming back from a break
1:2 (20s/40s)	Moderate	Good for learning without dying. My recommendation for beginners.
1:1 (30s/30s)	Challenging	Where most people should train most of the time
2:1 (40s/20s)	Hard	You'll feel the rest isn't enough. That's the point.
4:1 (Tabata)	Brutal	Four minutes of hell. Use sparingly.

Two Workouts I Actually Do

Instead of a list of 20 options you'll never try, here are two I actually use regularly:

The "I Don't Have Time" Workout (20 min)

Timer: 30s work / 30s rest, 20 rounds

This is my go-to when I have 20 minutes and need to move. No equipment, no excuses.

1. Jumping jacks (get the heart rate up)
2. Squats (keep form even when tired)
3. Push-ups (knees is fine)
4. High knees (quick feet)
5. Plank hold (catch your breath-ish)
→ Repeat 4 times through

The Finisher (4 min)

Timer: Tabata (20s work / 10s rest, 8 rounds)

I use this after weight training. Pick ONE exercise and go all-out.

• Burpees if I want to hate myself
• Mountain climbers if I want to "only" hate myself a little
• Jump squats if my upper body is already fried

Lessons From Doing This Wrong

I learned some of these the hard way:

Warm up seriously. I pulled a hamstring skipping warmup. Five minutes of light movement saves a lot of pain.
Don't do HIIT every day. Your nervous system needs recovery. 2-3 times per week max. I tried 5x/week and crashed hard.
Dizzy = stop. Pushing through dizziness isn't tough, it's stupid. Take a longer rest.
Form matters more tired. When you're gassed, form breaks down. That's when injuries happen. Slow down if needed.
Hydrate before, not just during. If you start dehydrated, you can't catch up.

Give It a Shot

I built our Interval Timer specifically for this kind of training - loud audio cues, big visual countdown, customizable intervals. Set it up once and focus on the workout, not the clock.

Open Interval Timer