Slow Down When Exercising To Burn More Fat

Slow Down When Exercising To Burn More Fat

Misleading information can make exercise more complicated than it should be. Fitness tech company Digifit dispels common cardio workout myths and says that while you might burn more calories with a harder workout, a slower one will burn more fat.

Picture: Steve Garner

The best method for burning fat at a higher percentage is a steady, consistent workout in Zone 2 (60-69% max heart rate), the fat burning zone. This zone uniquely targets fat because fat is a slow burning fuel, so if you do a long and less-intense workout, your body will target a higher amount of fat cells then carbohydrates. While you may burn more net calories in higher heart rate zones, you will burn the highest per cent of fat calories in Zone 2.

Pushing yourself too hard too often isn’t good for you anyway, so it’s a good idea to make those intense workouts the exception rather than the rule. For more heart training myth busting, check out the full post over on Digifit.

5 Heart Rate Training Myths [Digifit]


  • All online publications should really run their contributors’ work through Grammarly.

    Higher THAN – not THEN!

    (this is not aimed at LH, but the linked article doesn’t have comments…) /rant

  • I’m so sceptical when it comes to the “fat burning zone” and such strategies to lose weight. It may be slightly more beneficial but it’s so much more about the food you eat than the exercise you do. You can be skinny and never exercise (although you can’t be “fit and healthy” and never exercise).

    In terms of exercise, what athletes look the best at the Olympics? 100m sprinters do imo. Short, fast 100% effort athletes. Do you think they train in “Zone 2” to look like that? I know they don’t.
    Marathon runners on the other hand (while I’m definitely amazed at they’re ability to run and respect them for it) look rather sickly to me and can’t sustain 100% effort for the hours it takes to complete the run (they run a whole heap faster than I can though, lol)

    I know I’d rather look like a sprinter than a marathon runner, so I train like a sprinter rather than a marathon runner

    • That’s all well and good once you’re in reasonably shape. But the aim here is to burn fat (lose weight) – not really an issue for Olympians.
      When you think about it though, the whole science of exercise kinda happens naturally in that an overweight person is likely to start exercising at a lower intensity to begin with anyway dictated by their fitness, which would result in fat loss, then as this fitness improves so will the intensity of their exercise which would improve their cardiovascular health.
      Otherwise, I guess the unfit, overweight person who tries to start with the high intensity training will likely give up anyway

  • You completely misunderstood the article when you say things like “…while you might burn more calories with a harder workout, a slower one will burn more fat.”

    A ‘slower’ one will NOT burn more fat (in absolute). The only thing that matters is total absolute fat loss.

  • The real question is: in terms of net fat loss, what is the comparative effect size of creating a bigger caloric deficit (e.g., flat out for 30 minutes) compared to trying to burn fat while exercising (e.g., slow and steady)?

    I.e., is it more effective to exercise flat out for 30 minutes and burn way more calories (but less fat in the process), or spend the equal amount of time in the so-called “fat burning zone” and burn less calories in the process? My understanding is that, all else being equal (e.g., diet), the difference is negligible, as the body will go to the fat stores anyway if there is a caloric deficit.

    • Not quite. The body will happily burn muscle if it needs the energy. If the article is correct then it would suggest that a slow run burns fat while a hard run uses more calories. Therefore, if you run too hard (intense but not high intense) for too long then you will burn more calories but those calories will be made up of muscle and fat and not fat alone, which is achieved from the long slow exercise. At least that’s how I’m reading the article.

  • Re: the above – perhaps macronutrient partitioning may be the answer. Higher carb intake might mean that “the fat zone” may have more relevance to net fat loss; however, if carb intake is low-moderate, my guess would be that greater caloric deficit would be more effective. I’d love to know what a dietician thinks about this.

  • I’d prefer to look like one of the healthy Aussie swimmers. Most female runners don’t have breasts to speak of, some have even deliberately taken steps toward that, and to me, that’s not the best look for a woman. It’s a growth-stunted tomboy look. I don’t train like ANY sort of running-based athlete, because I don’t have the body type for it. The bouncing would wreck my chest years before its time! My activities of choice are swimming and cycling, in terms of Olympic sport. And Pilates. All of these are more fat-burning than carb-burning, even in the case of cycling, where I’m more about distance covered than average speed.

  • Those excess calories you’re not burning while you’re in the fat burning zone are going to turn into fat anyway. Therefore the argument is void.

    That being said, if you are also training to put on muscle, then the excess calories can be used to go into muscle bulk, but at this point you’re starting to talk to athletes who are on pretty controlled intake diets anyway, so again, your argument is void.

    • Assuming of course those excess calories are in the form of protein and are available during the actual exercise. Usually folks take protein after exercise for muscle repair/gain if its the readily available protein types.

    • By the same token, If you can sustain 60% effort for an hour, but 90% effort for only five minutes, you are going to burn a lot more energy at 60% – that potentially cancels out your counter argument one.

      I wasn’t quite sure what you were trying to say with argument two. But if it’s that putting on additional muscle burns more energy 24/7, then yes. You should incorporate some strength training if you want to lose weight long term.

      However I believe what the original artile was trying to say was “sustained easy effort is better than short sharp effort for fat burning in aerobic exercise”, not “low intensity aerobic work is better than high intensity strength training overall”.

      • Gotta agree with your point on sustained effort. However if you’re burning 20% more energy, you can exercise 20% less, which helps a little.

        Also, studies have shown that more intense exercise has a better ongoing effect, improving metabolism, which burns fat while you’re not exercising.

  • As the posters above have hinted at, the situation is much more complicated than the article makes it appear. Short intense workouts build more muscle mass, and consume more calories during recovery, and that extra muscle mass burns more calories every minute that you carry it.
    The only fat burning strategy I have ever found effective is to exercise before breakfast in the morning – a swim, a run or a ride. Sometimes supplemented with L-Carnatine to assist the process.
    On the reverse side of the argument, low intensity exercise is a good way to build up to more intense exercise, avoiding injury. Low intensity exercise is also a great base for high intensity exercise, helping improve further and faster and achieve a higher cardiovascular fitness level.

  • Clinical studies have shown that between exercise bouts of 50% of maximal oxygen capacity (V02max) for 60 minutes constant work, and 150% V02max for 40 minutes at 30 seconds work-30 seconds rest intervals (ie both have equal workloads overall), the high intensity interval protocol resulted in a greater net energy utilisation, both during the exercise and recovery.

    In short, low intensity exercise burns more fat than carbohydrates, while higher intensity exercise creates a greater net energy deficit overall, which is ultimately what is most important when considering fat loss. The particulars of substrate partitioning have more significance in performance than net energy balance.

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