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HIIT – High Intensity Interval Training For Maximum Fat Loss

girl sprinting at the track

What is HIIT Training?

HIIT stands for high intensity interval training. HIIT is an exercise method in which you switch back and forth between short intervals of high intensity exercise, followed by short rest or recovery periods.

Studies have shown that HIIT can be effective for both sprinters and endurance athletes and it can be incorporated into just about any training protocol whether it be weight training, sprinting, rowing, climbing, or sport specific workouts.

The key is to pick exercises that use the majority of muscle groups. Using HIIT for isolation exercises will be ineffective. However, using them for full body exercises like sprinting, squats, deadlifts, and plyometrics will really kick your fat loss into high gear.

Benefits of HIIT Training

The benefits of HIIT training are several-fold. Probably one of the biggest benefits is that HIIT usually lasts only 20 minutes or less. This enables just about anyone to be able to get in a great workout regardless of their busy schedules. After all, we can all wake up 30 minutes earlier to get in a workout.

The best thing is that this short 20 minute workout will probably be one of the toughest you will ever do. By working at close to your maximal heart rate, you will be burning the most calories, and causing the most physiological changes to your body that will be beneficial to fat loss.

Not only will you burn fat during your workout, but you will continue to burn fat throughout the rest of the day through EPOC (excess post-exercise oxygen consumption). EPOC is the measurable increased rate of oxygen intake following strenuous activity intended to erase the body’s oxygen debt [1].

In order to erase the body’s oxygen debt, fatty acids are released and used as fuel for recovery. This all happens in the time after a workout is complete. You will not receive this great benefit simply doing low intensity exercise. You need to be working out in your anaerobic zone at maximal heart rates to really see that added fat loss effect.

This EPOC has been shown to last for over 24 hours. While this is a great benefit, it also means you need to be allowing yourself plenty of recovery time between workouts – at least 48 hours.

Why Does HIIT Training Work

To sum up why HIIT works so well, lets recap:

  • HIIT lasts 20 minutes or less – resulting in a short workout time nearly anyone can integrate into their lifestyle.
  • HIIT can increase VO2 max for both high intensity and endurance athletes. VO2 max is the max amount of oxygen a person can use and transport during exercise. You want this number to be high because it enables us to use more fat as fuel instead of glucose. Since our fat stores tend to be much higher than glycogen stores, it is preferential to be able to get the highest percentage of fuel from fat during exercise. While sprinting uses a high amount of glycogen because it is such high intensity, the rate at which you change from fat burning to sugar burning is higher in individuals with a higher VO2 max.
  • HIIT increases EPOC (excess post-exercise oxygen consumption) resulting in an elevated fat loss state for up to 24 hours after you finish your workout – something you won’t get from lower intensity exercise.
  • HIIT trains the body to effectively remove metabolic waste from the muscles between intervals. By quickly removing lactate and other byproducts resulting from high intensity exercise, you enable the body to be primed and ready for another bout of high intensity exercise with less rest.
  • HIIT is one of several ways to boost both testosterone and growth hormone levels. Since these hormones are highly responsible for muscle gain and fat loss, you should be doing all you can to keep levels high.

HIIT Workouts

The combinations are endless when it comes to HIIT workouts. We could do any combination of intervals, but here are a few examples:

HIIT training for on the track:

  • Sprint the straightaways and walk or jog the curves. Do this for 20 minutes.
  • Sprint 200 meters (half way around the track) and walk/jog the other half. Do this for 20 minutes.
  • Sprint 400 meters (1 lap) and then walk/jog the next lap. Do this for 20 minutes.

Off the track you will want to do similar intervals, but use time as a measurement instead of distance:

  • Sprint for 15 seconds and walk/jog for 30 seconds. Do this for 20 minutes.
  • Sprint for 30 seconds and walk/jog for 60 seconds. Do this for 20 minutes.
  • Sprint for 60 seconds and walk/jog for 90-120 seconds. Do this for 20 minutes.

HIIT training in the gym:

  • Squats for reps for 1 minute and then rest for one minute, then repeat for 20 minutes.
  • Deadlifts for reps for 1 minute and then rest for one minute, then repeat for 20 minutes. Note: Make sure you are using the right form with these.
  • Circuit training – mix up squats, bench press, deadlifts, and pullups, doing 1 minute of exercise for every 1 minute of rest. Repeat for 20 minutes.
  • Bodyweight HIIT training – combine bodyweight squats, pushups, and pullups for 1 minute of exercise followed by 1 minute of rest. Repeat for 20 minutes.
  • Box jumps – jump onto and off of a box as quickly as possible for 1 minute and then rest for 1 minute. Repeat for 20 minutes.
  • Jump rope – jump rope for 1 minute of exercise followed by 1 minute of rest. Repeat for 20 minutes.

By now you should have the idea. The key is to do a full body exercise for a certain period of time, and follow it up with a short rest interval, and then get right back into it.

Yes, you are going to be breathing hard and not fully recovered before you start your next working set, but that’s what makes HIIT so effective. Your goal is to be able to work out at a high intensity for a longer period of time with less and less rest between intervals.

To progress with HIIT, you are going to want to vary your interval times. Try lowering the amount of rest time between high intensity intervals, or try jogging instead of walking. Try shaving just 5 seconds off of every rest interval each time you work out. Eventually, you will be sprinting at a higher speed for a longer period of time than when you started.

Why not give high-intensity interval training a try. You don’t need to do it every single workout, but maybe do it once a week to start to see how it goes. Be sure to give yourself a good warm up period to prevent injury, and be sure you have an interval timer to use to keep track of your interval times. Good luck! I wish you great fat loss in your future.

  • Doug

    Not only are HIIT workouts shorter and way more fun than slogging away at a treadmill doing “cardio”, but there is a ton of research showing that HIIT workouts provide unique heart health benefits that traditional cardio doesn’t

  • Coach Calorie

    Very true Doug. HIIT has so many benefits, yet people are afraid to push themselves out of their comfort zones. Thanks for the comment.

    • Paula

      Hi coach calorie, I do hiit on my rebounder .. High knees/ kick backs ect.. I leave a day inbetween exercises.. Should I be doing some other kind of workout on my off days? Is it really enough to just work out 3 days a week? I also do mountain claimers are these really effective for belly cause I really feel it in my legs not abs …

  • allie

    I do interval sprints on the treadmill when i have the fortitude and discipline to drag myself up there and hit it. I always feel better and accomplish alot in 20 minutes…SMH at the folks in “fat burning” mode walking in slo mo right next to me for hours on end…

    • Coach Calorie

      Hey Allie, the fat burning zone will die a slow death.

  • Marci Campbell

    I’m going to try this today when I go to the gym!

    • Coach Calorie

      Let me know how it goes Marci :)

  • Char

    This is the second time I’ve seen an article about HIIT recently. It intrigues me. I like the short duration because it can be challenging for me to schedule a workout during daylight hours. A few weeks ago, I started doing Couch to 5k every other day but not feeling like I am getting “enough” of a workout. I see options that I could do at home (like the body weight minus the pullups, box jumps, and jump rope) working around my children’s schedule.

  • Josh

    I’ve been jogging around the local highschool track for 3 miles without knowing this is more effective workout. I will integrate this and see how it goes. Thanks for the great tip!

  • Donna B.

    I can do the squats (well, for the most part) and the lifting – I’ll have to give this a try. I’m ready for some variety in my workouts and getting some high intensity will definitely help my weight loss as well as my cardio.

  • Carm

    When I run on the treadmill I usually run for 2 mins at a speed of 5.4 and then 2 mins at 7…..I try to do this for about 20 – 25 mins. Is this benifical?

    • Coach Calorie

      Any exercise is beneficial. It’s hard for me to know the speeds and how hard they push you. Just make sure 7 is hard. You can always switch it up too. 30 second on and 30 seconds off. 2 minutes is a long time to sprint. I would try to keep HIIT training to under 1 minute.

      • Carm

        Thank you! I will defintely try what you suggested. I’m glad I found your site. All of the information posted is helpful!

  • Sandor Lengyel

    Great article. Just discovered your blog and have been doing lots of “catch-up” reading. Any suggestions on how to integrate HIIT strength training for longtime endurance athletes (usually 2-5 hours/day of cycling, running, SUP, xc skiing, etc.)

    My personal experience is that the HIIT strength training can ruin the quality of endurance workouts. (Too many squats or deadlifts or other heavy weights often makes for lousy climbing intervals on the bike). Endurance folks like myself tend to be unbalanced on the cardio/strength side, and it’s a challenge to integrate strength training into my workouts. Traditionally bike racers and other endurance athletes do their strength training in the off season, but it gets neglected during the summer. The challenge is integrating it all year long.

    • Coach Calorie

      Thanks Sandor. There is always a way to incorporate HIIT into your fitness routine – you just need to keep it sport specific. You can do HIIT on your bike and it will help you in the tougher hills and sprint portions of your race, as well as increase your VO2 max – which will in turn help your overall endurance.

  • Freddie Jackson

    Hey Coach, would you suggest HIIT training while trying to build muscle? Or more for fat loss? Wondering if I should start now or wait until May when I usually work hard at losing that extra winter fat…

    • Coach Calorie

      Hey Freddie, you can certainly build muscle doing HIIT. HIIT in and of itself can put on muscle. However, if you are a bodybuilder, or have a hard time putting on weight, you might want to hold off. If you’re just trying to put on a decent amount of muscle and be lean (ie be atheletic), HIIT will benefit you.

  • Channn

    I have lost 45 pounds in 4 1/2 month, doing the fat burn zone for the past 3 month on my threadmill. Working out at home.
    I have a POLAR watch that target my heart rate and now after 3 month, I can hardly get to 70% MHR while simply walking. I am now doing 5 min warm-up, 2 minute at 90% of my heart rate & 3 minutes going down to walking & I reapeat theses step for about 40 minutes. Is this good enough for HIT Training?

    I really love your web site, it contains so much questions & answers that is good for someone like me that is getting back into shape.Thanks again,,,,

    • Coach Calorie

      That would seem to work for HIIT. I wouldn’t go much longer than 2 minutes though. You should be going at max effort for your sprints. It’s hard to do that with such a long interval. Ideally, I would rather see you sprinting max effort for a max of 1 minute and taking a 1 minute break. You don’t want your heart rate returning to normal – just enough to catch your breath for the next interval.

  • Lisa

    This website has really opened my eyes! This is definitely some of the best advice I have ever seen and even better, it feels like it’s really achievable.
    I’m looking at HIT in conjunction with your post on the ‘How to Lose 10 Pounds in a Month’ and I have a couple of questions if that is ok?!
    – I tried interval training on the treadmill last night – 30 seconds running as fast as I could go followed by 60 seconds of fast walking on an incline. I actually thought I was going to pass out/by sick/kill myself but that’s the best I have ever felt at the gym…….does that sound right?! I felt like a bit of a cheat coming in and doing 30 min stint (including warm up/cool down) but I could spend over an hour doing a variety of things and not really pushing myself.
    – If I hit the gym 6 times a week (3 x HIT, 3 x strength/weights) does that sound about right? Should I be using the HIT principles for the weights days or focus on being steady with the weights and taking the appropriate amount of time to do them?

    Thanks in advance :)

    • Coach Calorie

      I’ve felt like I was going to pass out before too. After some Tabata sprints on the stationary bike I usually have to go lay down.

      Focus on strength training for your weight days. No need to do intervals. You’ll be doing HIIT the other days. Just make sure you are doing compound movements with good intensity.

      Keep you diet good. You’ll be doing quite a bit of intense exercise. You could probably get away with 2 HIIT days and 3 weight training. Listen to your body.

  • Donna

    HI Coach Calorie! Another great article, thanks!

    Thanks for the link to the heart rate calculator however, I have a question for you. I have a very low resting heart rate, particularily for a woman. Perhaps this is just normal for me or it is a result of years of cardio!!!

    I love HIIT, but I find that the results of the typical heart rate equation is too low for me. Hence, I am not working intense enough. So I use a calculation that takes into consideration my resting heart rate. As a result, the difference between the two equations if quite a bit but I feel I am working much more intense with when I use that one.

    I wear a heart rate monitor faithfully for HIIT so I can ensure I am meeting my 85%+ HR.

    Thoughts on the equations? I would love to hear your opinion!


    • Coach Calorie

      Donna, go with your actual measurements. These equations are just generalizations made from the common population. They are averages. There will always be outliers like you. The only way to know what your MHR is would be to physically measure it yourself, and that’s what you’re doing.

  • mjones332

    Is it really HIIT if efforts are longer then 15-20s? That is about the maximum amount of time most can do “all out” on sprints or efforts before the energy pathways fail and effort is reduced. I always thought beyond 20s it becomes more just interval training, even if you think your “going hard” with your effort level.

    I only say this because a very long time ago I thought I was doing HIIT for about a month, until one day I realized it was just intervals and not HIIT. The first actual HIIT session I did, I did 5-15s all out “sprints” on an elliptical at max resistance with 45s rest in between. I was gasping for air during this, and when I stopped I felt like I was blacking out for a brief moment, I went to walk my dog afterwards and I was shaking for about 15 minutes – it was true HIIT and my body was not ready for it.

    I recently refound this to be true when I joined a new gym, they have a woodway force treadmill where you can run against resistance. I feel like I am in great shape, I can do Jujitsu/Karate sparring without getting winded even with kids 10-15 years younger then me, I can also do other martial arts training for over 3hrs at a time and not be worn out. My first experience with this treadmill was nothing short of a reset on my thoughts about fitness. The trainer put it on 20 and ran a 15s sprint to show me how to use it, I got on it and put it at 35 (trainer laughed) and did a 15s sprint – my heart rate went to 200bpm instantly (its never been above 197bpm before in my other HIIT routines, and I am 34 year old). I did a second 15s sprint and thought I was going to puke – now I LOVE and SEEK OUT this type of activity, but that was it for my first round – I bowed out I was too far out of my comfort zone.

    I have been there maybe 5 times now, I just worked up to 5-10s sprints, and even that is taxing me and the last couple of seconds on my last 2 my pace slows as my energy is zapped. Doesn’t sound like anything at all right? Try it, and by try it I mean do maximal efforts not just jogging or whatever you feel you need to do to make it for 15s, it is a killer.

    • Coach Calorie

      It’s been debated on what’s considered HIIT, but I think it’s really just a technicality. There is no reason why you can’t go at 100% intensity for more than 20 seconds. Will your pace slow down? Sure, but that doesn’t mean you aren’t putting 100% effort into it.

      When I run 400m sprints, my heart rate gets just as high if not higher than 100m sprints, and I’m a lot more exhausted after them too. I think it’s best to mix it up, but if you can run a 400m in less than 60 seconds, I’d say that’s pretty intense.

      • Matt

        I agree with you but for myself personally I can only guarantee I am doing all out intervals (high intensity) when I am under 20 seconds. Above 20 seconds (and to me there is even a difference between 15s and 20s) it is really easy for me to slip into “hard intervals” instead of “high intensity intervals.” I think this is because I know how fast I should be going under 15-20s because there is a certain top speed on the force treadmill, elliptical, or whatever, but above 20s it becomes highly questionable what my rate should be as my energy pathways are obviously taxed and failing – it’s easy to lighten up and slow down and assume you’re still going all out because you expect the slowdown to be happening anyways.

        My triathlon friend used to make fun of me when I told him how killer 10s sprint 20s rest was in a true HIIT workout, I told him to try it and he just laughed saying I already do 1 minute sprints 10s would be cake. He tried it and said yeah it was easy for him that his heart rate didn’t even get higher than his marathon heart rate because he didn’t have enough “time” to really be worked hard, that there isn’t any cardio he can’t do better than high intensity fanatics because he works so much cardio in his training it’s impossible to tax his system with such short bursts.

        Well, he finally went to a training session with a coworker that was coached by a HIIT type coach – he was dying because the coach was forcing him into the HIIT zone not letting him linger in the sub maximal heart rates he always did before. He finally realized that a 10s sprint did not mean at 70/80/90 percent type efforts used by endurance athletes when they are doing “interval training” – it’s supposed to be all out not holding anything back.

        Anyway my point is, if you’re a good enough self coach to ensure you’re doing maximal efforts then I guess your intervals can be as long as you want and as long as your body allows you to without cardiac arrest :)

        Part of my issue with longer sprints is also that I feel I can over ride the safety systems a little in my body, I don’t know if I want to push myself that hard for up to a minute at a time. For example the last time I did sprints on the Woodway force my heart rate stayed above 190bpm even with 50s rest periods between my tiny 10s sprints, previous work on elliptical my HR usually dips 20 bpm from its max within 20s of rest except maybe towards the end of my intervals. This last time on the Woodway my HR finally dropped a little bit about 45s into the rest period of 50s, showing me that my body was having trouble recovering (good, means I am in a training zone that is pushing me). If I were doing 1 minute sprints, which for me would actually end up being 1 minute of a combination of sprinting, jogging, and then slow jogging – my heart rate would be thoroughly taxed the entire time. It is good to push yourself, but if you’re not seeing a recovery dip in HR during your rest intervals, I don’t think that is healthy to do every workout when you’re working in VO2 max HR ranges.

  • Dave Martin

    Has anyone tried this 4 minute cardio workout? What are your thoughts on it?

  • Jeff

    Great article. I’ve just started employing a form of HIIT Training this month, after doing low-impact cardio most of the year I did cardio. The changes/results are almost instant. I can’t believe I waited so long. I’ll definitely be doing high-impact cardio for fat loss from now on.

  • Aimee Shelton


    I just started working out again because I just turned 30 and figured it was a good time to get back into it. I realized in the last year that I had gained about 10 pounds out of nowhere so I’m trying to get back down to my normal size. I’m a fairly petite thin female, but I seem to be pretty out of shape. I started my regiment last month with Yoga three times a week to get my muscles stretched out and now I’m doing intervals on the treadmill three times a week. I do 30 minutes starting out with walking a normal pace at a 2% incline for 6 minutes and then I jog at no incline at speed 5 for 4 minutes. I go back and fourth until my 30 minutes is up and then I of course do the automatic cool down. Is this a good work out? I feel great afterwards and I work up a great sweat. I noticed that my shin’s were hurting the next day after my last workout, but I’m assuming that has to do with my shoes. I’m still doing yoga in between days to help keep stretched and limber. Any input on this workout would be helpful. Thanks!

    • Coach Calorie

      I’m not a big treadmill user, so I’m not sure what your settings relate to intensity wise. However, as long as you are pushing yourself, it’s always a good workout. Personally, I would cut down the work intervals and up the speed, but I’m not sure about your fitness level. The point in HIIT is to push yourself. Get your heart rate up during the work intervals.

      Your shins are most likely sore because of the incline you were working out on. It forces you to flex the muscles on the front of your “shin”, which can make them sore the next day.

  • Liga

    Hi Coatch. Just discovered your page not long ago, cant believe it i messed out so much. was trying to diet mad and fitness never liked it. I’m doing your HOW TO LOSE 10 POUND IN 30 DAYS, 8 days behind me and i feel so much better, now i’m trying to catch up with everything you write about. its like new world for me :) Thank you!
    my question is – can i mix any exercise for mu HIIT? say squats + mountain climbers + burbies … or box jumps + pullups etc? Is there some structure which exercises i have to put together or or doesn’t matter?
    sorry for wrong english, Fat Liga from Latvia

    • Coach Calorie

      Hey Liga, glad you like the site!

      You can mix them up. The key is to pick exercises that utilize several muscles so that you can keep the intensity high. All of those exercises look good to me.

  • Ali


    I am new to the HIIT. I tried one yesterday:

    Sprint 30 seconds
    Walk 60-90 seconds
    Sprint 30 seconds…etc

    I did this for 16 minutes. And somehow I found this much easier than doing a 10 minute jog. Am I doing this right?

    • Coach Calorie

      Depends, are you pushing yourself during your sprints? You might need to cut down on the rest intervals if you find it to be too easy for you. When you do intervals for 10 minutes are you making it a further distance than your 10 minute jog? This is a good way to figure out if you need to be pushing yourself harder.

  • Alex

    Hey Coach!

    I’m a high school student trying to keep in shape during the off sports season, and I figured that HIIT workouts were the way to go! After just a short while I’ve had a noticeable increase in stamina, and I can still keep up with my buddies in Cross Country on long-distance runs. My favorite HIIT is running straightaways and jogging corners on the track. I love this site!

    I also have a question: what is your recommendation for a good upper-body HIIT that doesn’t involve gym equipment? Without the time to go I’m finding it hard for my upper to keep up with my lower body.

    I can’t thank you enough :) HIIT changed my life!

    • Coach Calorie

      Upper body is a little more difficult, but not impossible. Look into upper body plyometrics. Combine those with pushups, pullups, bear crawls, and you have a total body workout. I like to do some upper body stuff with the agility ladder. Only costs about $20. Plyometric pushups are fun too.

  • Jerra

    As a newbie to fitness, coach calorie always has the best articles/advice…and I thank you for that!

    • Laurie Lay


  • Kym

    Is it correct for HIIT training involving sprinting and jogging that before I start the workout, I need to know what my maximum heart rate is to know if I’m putting in enough effort?

    • Coach Calorie

      Hi Kym, I wouldn’t go as far as saying it’s necessary. It can be beneficial to know what your heart rate is, but you should know from the way you feel if you are going at an exercise 100%.

      • Kym

        Thank you for the response. I’ll be looking into getting a heart rate monitor anyway, as I feel sometimes I may have the tendency to be a little lenient when I’m close to the end of a workout. Cheers!

  • Jen

    Is it best to do a treadmill HIIT before or after a weigh liftng routine? And how any times a week should you do HIIT? Thx

    • Coach Calorie

      I would do it after, as I like to make strength training the priority, but as with anything, it will depend on your goals. I’m currently doing 3 HIIT sessions a week. Just make sure you are leaving enough time to recover between your workouts.

  • Ryshel

    I am pretty new to working out and only started in April. The main goal is weight loss. Basically, the routine consists of 15 mins on the treadmill + time for warm up and cool down. During the fifteen mins I do high intensity for 2 mins, then walk for 1. I am going fast enough that I am pretty good for about 1.5 mins, but the last 30 secs. can be a real struggle. Should I do a higher intensity for 1 minute then walk for 1? Would that be more beneficial?

    • Ryshel

      Forgot to add that after that I work different muscle groups for another 30-40 mins. Basically on a rotation: abs/shoulders, back/bi’s, chest/tri’s. I am happy with losing weight, but I also love feeling stronger!

    • Coach Calorie

      I like doing shorter work intervals at a higher intensity. Then, over time, you start cutting down your rest interval times. Then, you can start increasing your work interval times. So on and so forth…

  • Monica

    I have a question. I live in SF where there are a ton of hills. I want to do the sprints but sprinting uphill kills me. What would you recommend for HITs here?

    • Coach Calorie

      Monica, you’re in luck – hills are awesome for HIIT work. Treat the hill as a natural work interval, and the flat/declining hills as rest intervals.

  • Pawan

    Hi, very gud article, it really works,I am doing it for 30 minutes -(30 sprint – 60 jog ratio) alternate day, I jus want to know about the diet, which is most preferable diet while doing HIIT.

    Thanks in advance.

    • Coach Calorie

      If you’re going to be doing a lot of high-intensity work, you need to make sure you’re eating enough carbohydrates to fuel it. Other than that, I like to set my protein intake to 1 gram/lb of lean body mass and then fill my remaining calories with healthy fat.

  • Sarah

    When I participate in this particular training i usually sprint hard for 45 seconds at 7.5 speed and 3.5 incline, and walk or jog during rest periods for 30 seconds. I usually do this for 20-25 followed by a 5 minute cool down. Is this beneficial for toning and overall fat loss? Also am I allowing enough time during my rest periods to get my heart rate back down to, before increasing my speed again?

    Thanks so much

  • Ben Smith

    I’ve heard of the program, and a buddy of mine had the dvd. And on the dvd, it broke down different types of work outs, and the nutrition part of it. Was wondering if there is way to get a copy?

    • Coach Calorie

      Hi Ben, HIIT really isn’t a program, it’s just a way to train. You use alternating intervals of work and rest. Plenty of exercise programs incorporate some form of HIIT into them.

  • Cindy

    Great Article! Although I had read some of this already, I’m a little confused on aerobic vs anaerobic–my husband claims that anaerobic builds more muscle while aerobic is better for leaning that true?

    • Coach Calorie

      Anaerobic definitely builds more muscle, but leaning out is a function of your diet.

  • Roxanne Gillenwater

    Hi! I’d like to try HIIT, but my treadmill only goes to 4.0 mph. Since I’m not able to run or sprint on it (because I bought the cheapo kind…doh!), could I walk for 45 seconds, then get off and do jumping jacks/jump rope/jog in place, etc. for 45 seconds, then get back on and walk, and repeat? I guess my question is, is it all right to get on and off the treadmill like that when doing HIIT?

    Thanks for your article!

    • Coach Calorie

      Other than safety concerns, I see no problem.

  • Aeryelle

    I’ve been doing HIIT (arguably) using a popular home workout program. The program is designed to go 6 days per week, one of the 6 days being a “recovery workout”, and then only one true rest day. After reading your article, it seems the 48 hour recovery period is an integral part of the training.

    What does this mean for a program that utilizes HIIT with 24 hours or less between sessions? Would it not be as effective?

  • Jan

    Hi coach,
    I am a 64 year old woman 5 feet 3 inches and weigh 145 pounds. I want to get to 135. I do 45 minutes cardeo and 30 minutes weights every other day. Since i have a knee problem, how to get my level to high intensity. I go upto 128 in my elliptical.
    That is what i use in addition to stationary bike.

  • Coach Calorie

    Hard to say without personally assessing your range of motion. You can increase intensity levels by increasing time, increasing resistance, or by decreasing rest times. But again, have your knee assessed first.

  • Coach Calorie

    I believe I know the program you are talking about. It certainly is not impossible to do high-intensity exercise every day – olympic and elite athletes do. However, they also work up to that amount of exercise so as to prevent injury and overuse injuries.

    Take it slowly so that you don’t run your motivation into the ground.

  • ErinaSizzle

    I am doing insanity and each interval last 3 minutes with 30 seconds gap in between each set. Altogether it has 9 intervals. Does his count as HIIT training?

  • Deanna Schober

    Definitely. As long as your heartrate gets way up there during the intervals.

  • Ayesha Umar

    hey coach,according to you we need 40mins of workout,20 mins of cardio and 20 mins of exercise….do we need another 20 mins of cardio in the end too…?

  • Jeff

    HIIT is good for variety and time-efficiency, but the whole “EPOC” thing has been proven to be false by several university studies (Google it). It doesn’t burn any more fat than steady state cardio.

  • Coach Calorie

    Hi Jeff, can you show me these studies? The scientific literature has overwhelmingly proved the opposite time and time again.

  • Laurie Lay

    In your article you said,
    “You need to be working out in your anaerobic zone at maximal heart rates to really see that added fat loss effect”.
    How do I figure out what my Anaerobic Zone is?…
    and How do I figure out what my Maximal heart rate is?…

  • Coach Calorie

    Max heart rate is 220 minus your age. Your anaerobic zone is usually around 80% of your max heart rate.

    • Laurie Lay

      Thank you

  • Coach Calorie

    I’m not sure what you mean Ayesha. Where do I recommend a 40 minute workout? HIIT workouts are about 20 minutes in length and that should be plenty.

  • Andie Romo

    I am starting exercising to lose weight for health reasons. would this work with the stepper i have at home? or better with the exercise bike?

  • Coach Calorie

    Can you get your intensity up on the stepper? It’s all about your intensity levels.

  • Cynthia Garibay

    I’m 17 years old I recently noticed I was gaining some extra weight my body type is what some people call “thick” I want to loose weight in less than a month what is the healthiest and most hardcore work out you recommend ?

    • Coach Calorie

      There are plenty of example HIIT workouts in this article, but the biggest difference is going to come from your diet.

  • Meghan

    I recently started HIIT workouts and I love them! I also started strength training. I’ve been doing the HIIT workout and then a 45min strength training DVD immediately after, usually late at night. I’ve been going every other day, and using the rest day to relax or maybe go for a long walk. If my goal is fat loss and toning up (I’m about 30 pounds overweight), should I be doing the HIIT workouts or strength training first thing in the morning, before breakfast? Also, should I do the HIIT and weights on different days? And does it matter if I do HIIT first or weights first? Again, my goal is fat loss. Thanks! So glad I found your site!

  • Marts

    Ok, so I’m overworked, my timetable is really full (i work 6 hours a day and go to uni another 6 hours), that leaves me little time to do anything. I’m fat, and these last two years i’ve put on a lot of weight. My routine results scared me. I’m not trying to over do it, a steady routine to keep my health in check. I was toying with the nowadays famous 7 minute a day excersise and this hiit… What would you recommend?

  • Liz

    Hi coach,
    First Thankyou for the fantastic info, I’m a new avid follower.
    I do home gym 3 days total body ( STS or muscle Max 60 minutes and on alternate days I have started doing HIIT on my spin bike 3 days a week. As I’m new to HIIT I do 4/5 minute warm up then 20 second sprint flat out on my sprints 40 second recovery, I do this for 8 minutes then cool down for 5 minutes 17/18 minutes total. I’m finding its all I can do at the moment but what should I be aiming for ?

  • Jamie Robertson

    Hey Coach – thanks for the article! I saw a video on this from Dr Mercola last year and tried it a few times, but your article inspired me to get back at this today, so thanks!

    My question is this: My main sports are Mountain Biking (all mountain style) and hiking/scrambling. I did HIIT on a pathway on a hill because both of those sports use a lot of Quad muscle. Is it better to do HIIT on relatively flat ground instead?


    • Coach Calorie

      I think a mixture of hills and flat ground would be best for you. Keep it sport specific.

      • Jamie Robertson

        Sounds good – will rotate between shoes and tread :)

  • Bee

    When repeating for 20 mins, does that mean 10 mins rest/10 mins work or 20 mins rest/20 mins work?

    • Coach Calorie

      The HIIT time typically includes the rest periods.

  • Coach Calorie

    In the end, the best way is going to be the way that you stick to it the longest. Doing both on the same day is too much for me, but if you can handle it now and continue to do it a year from now, there is no problem. Just make sure you are eating to fuel that much activity and you are recovering.

  • Coach Calorie

    I would recommend HIIT, but more importantly, get control of your diet. That is going to make the biggest difference for you.

  • Coach Calorie

    Try to get at least 10 sets of sprints in.

  • Karri

    This is what George St. Pierre’s workout DVD is like…. half an hour is brutal ! :)

  • Bee

    You are so awesome Tony! I love all your articles. I just finished a college nutrition class, so I know your not just making things up lol. Whenever I open an article first thing I do is make sure it was written by you lol. Your work definitely inspires me, keep up the amazing work! Your work is just so awesome, can’t say it enough…

  • Nancy Palazzo

    I lift weights five days a week. I also run, bike and sprint. When I do legs, I don’t do cardio, as it’s too exhaustive. Is it better to do HIIT or run or bike the day after legs? Or, should I take that day off from cardio all together?

    • Coach Calorie

      I usually take lower body off the day after leg day. I may go for a walk as active recovery to get blood and nutrients to the muscles and speed up the recovery process.

  • Herb

    I’ve been exercising for decades and I recently started using HIIT-it’s by far the best form of exercise I’ve ever used.I feel so virile and healthy,and I look slimmer,healthier and younger.I’m hooked on HIIT for life.

  • Emil

    Theoretically HIIT is true. Lactic acid is what turns fat into keto acids. Lactic acid is produced anaerobicaly. So at the height of the intense part when your lungs can’t keep up is perfect. Then you need oxygen to convert this keto acids into glycogen, then glucose, then ATP

  • Tony Schober

    It’s going to depend on the individual. There is no set rule. Personally, I like to eat 50/25/25 (carb/protein/fat).