High-intensity, interval training is fast and intense, but is it good for you? There are many things to love about HIIT: You can zap calories fast. (You’ve heard of 15- and 20-minute workouts.) Unlike some fitness trends that rely on fancy gym equipment and weights, HIIT requires little to no equipment. You can do your workout practically anywhere: in your living room, bedroom, garage or park. And finally, there are also oodles of online videos and streaming services available, making it even easier to do from your own home.
Given’s HIIT’s growing popularity, we wanted to know all the pros and cons and how-tos of this fitness trend, so we turned to Dr. Oz’s personal trainer and fitness expert Joel Harper. Harper is a celebrity personal trainer who you might have seen with Dr. Oz. (Visit Dr. Oz.com to see Harper coaching him through dozens of workouts.) But he’s also trained Olympic medalists, as well as well-known actors preparing for new roles, musicians embarking on world tours and business executives. His books include the personal workout chapters in the New York Times best-selling YOU: books series and the accompanying workout DVDs with Drs. Mehmet Oz and Michael Roizen as well as the popular FIT PACK DVD. Here’s what Harper has to say.
1. What do you like about HIIT?
High-intensity interval training (HIIT) is an excellent way to use your workout time very wisely. I find most people are extremely busy and have a huge check list of to-dos and have a limited amount of time to get a workout in. With that in mind, I love being able to use my time efficiently to get a good burn in in a quick amount of time.
2. Is HIIT good for fat loss?
Without a doubt. There is a considerable amount of research that shows exercising in as little as 20 minutes can burn calories which results over time in fat loss. The reason for that is that higher-intensity exercises result in a great disturbance of the body’s homeostasis. When you rev up your metabolism by doing a HIIT workout, your body can function the way it was designed. As we all know perfectly well, the better our body flows, the lighter/better we feel. The key is being consistent over a considerable period of time. Personally, I would say give it 6 weeks.

Consistency is key to long term fat loss: Even 20 minutes a day of HIIT over a period of several weeks can show results.
3. What is the advantage of HIIT?
Heart health. Period. HIIT workouts offer an improvement in your oxygen uptake. The more aerobically fit you are, the healthier your heart is.
4. Is HIIT for everyone?
HIIT workouts are not for everyone; whether or not they are for you is a question only you can answer. I find that every one of my clients is unique and I have to help them find out what works best for them and their body type and personality. For example, some love working out first things in the morning because it sets up their day for success. Others are lethargic in the morning and would be irritated that they couldn’t give it their best, so evening workouts are better for them. All I say is give HIIT workout a try for a minimum of 4 times and then make a decision.
5. Are there any disadvantages?
I am a big believer in doing an exercise, then doing a stretch, and repeating this cycle. I like to get a good burn in and then open the muscle up right away. This way I always leave a workout feeling energized and tension-free. With HIIT, I find the stretching gets left to the end or not at all. If one of my clients went into a workout with any sort of muscle imbalance, they may not have realized it and gotten unnecessarily hurt.

Don’t forget to stretch! With short HIIT workouts, Harper says stretching is often neglected.
6. What would you recommend for someone new to HIIT?
If cost were an issue, I would recommend trying some workouts on YouTube in the comfort of your own home. Watch the workout first to make sure you understand all the instructions and exercises so you can do them safely. Then I would try it out a few times to see if it is a good fit for you. Don’t expect to be perfect the first time, and understand that there is a learning curve. Or hire a personal trainer to do it with you on FaceTime or Zoom … then you could have a workout tailored to you and your specific body type and fitness level.
7. Important takeaways about HIIT or workouts
a) Efficient use of time
b. Revs your metabolism
c.) Great for cardio/heart health
If you want to learn more about Harper visit his website or subscribe to his YouTube Channel to sample his workouts. For more ideas on HIIT workouts see these Smart LifeBites stories: The Case For HIIT Training or 5 Steps to Holiday Fitness.
–Patty Yeager