Theres a lot of talk these days about HIIT and LISS and you’re probably wondering what they mean, both of these are methods of cardiovascular fitness or cardio for short. Its no secret that doing cardio keeps your heart healthy and a healthy heart lowers your risk of chronic illness and diseases but many people look towards cardio as a method of weight loss, reason being that to get the blood pumping you need to be active, and this burns calories helping you create a calorie deficit.
What Is Your HR Max?
Your HR max is the maximal beats per minute your heart can endure. The best way to predict your HR max is to take the number 220 and minus your age. For some it will be a little less than this, some more. This all just depends on your level of fitness. Those who are very unfit will have a much lower HR max than those who are fitter, meaning they will be tired and breathless at lower intensities. You’ll reach your HR max when you are working at 100% effort, but you can not work at high intensities for long periods of time because the body cannot get oxygen in as fast as it uses it and we rely on aerobic systems, so high intensity work is done in short bursts. All cardio methods involves you working at a % of your HR max.
LISS – Low Intensity Steady State
LISS cardio involves you working around 60-70% of your HR max for a longer period of time, its an aerobic exercise because your body uses oxygen and therefore burns a higher % of fat than carbs. LISS requires much less effort than HIIT, is much less stressful on the body and you can complete LISS sessions more frequently than HIIT sessions. You do burn less calories than HIIT, therefore it takes up more time and some may find it boring.
HIIT – High Intensity Interval Training
HIIT is done wrong by so so many people who think that its working at high intensities followed by low but this is incorrect. HIIT is working at 100% of your maximal HR followed by a rest period. If you don’t need the rest, i.e You could carry on working in a lower intensity then you didn’t work at 100% max during the high intensity burst. The pros of HIIT include; Shorter Workouts – perfect for those who have very busy lives, you burn more calories in a shorter period and you get a greater hit of endorphins. The cons include; increase of injury due to the intensity, HIIT is exhausting and stressful on the body and it takes time to recover between sessions.
Which Method Is Better?
Well that all depends on your goals and what you want to achieve from doing cardio. You’ll never regret a workout, thats one thing for sure. Getting those endorphins pumping is always a great thing. Theres one thing that must be said before we move on, only do what you can do. If you can’t find the motivation to do HIIT workouts, then stick to steady state. The important part is that you’re active and taking control of your health.
You often hear of something called “the fat burning zone” when it comes to cardio and what it means is, because you’re working at a lower heart rate and using oxygen, you burn a higher % of fat than carbs for exercise fuel. What “the fat burning zone” fails to state is that you do not burn as much fuel (calories) in a lower heart rate because the exertion is not as high. So lets say for example you burned 100 calories during a 15 min LISS session and 60% of that was fat, (60 cal from fat) but you burned 250 calories during a 15 min HIIT session and 35% of that was fat (87.5 cals from fat) – really you’ve burned more fat calories during HIIT than LISS. And HIIT creates EPOC effect which means your body keeps burning fat for up to 24 hours after you’ve worked out. Another thing that gets stated is that because you burn a lower % of fat, you therefore burn a higher % of carbs meaning once carb stores are depleted you’ll start using muscle for fuel, and while this is true, its taking it to extremes. As long as you keep your HIIT session within 20 mins, aren’t creating large calorie deficits within your nutrition intake and have a good post workout meal after, then you have nothing to worry about.
Your Cardio fitness is the efficiency of the heart’s ability to pump blood and oxygen around the body. Improving your cardiovascular fitness won’t just give you a better quality of life, but will allow you to exercise longer without being as tired and also helps improve brain function. Current research shows that the quickest way to improve cardiovascular fitness is to combine HIIT and LISS together using LISS more frequent and HIIT less frequently to increase peak oxygen intake, lactate and aerobic threshold and improve aerobic capacity (they all link up with each other).
By improving your cardiovascular fitness an added bonus (apart from looking and feeling better) is that it comes with health benefits. These include: reducing the risk of heart disease and stroke, lowering blood pressure, lowering your risk of type 2 diabetes and lowering your risk of osteoporosis.
Let me know in the comments below which cardio method you prefer.