HIIT or LISS? The debate on which is better has been going on for years now, with people still unsure on which is the greater form of cardio. Lets get down to the basics first. HIIT is High Intensity Interval Training. For example, 15 minutes on a bike – 1 minute all out, 1 minute at a steady pace and repeat. LISS is Low Intensity Steady State. For example, 45 minutes on an incline treadmill at a comfortable speed.
Cardio Training and Your Goals
First of all, I believe that the choice of cardio really depends on what your goal is. If you’re on a low carb, low calorie diet realistically you’re going to be low on energy and glycogen. HIIT cardio will decrease glycogen almost immediately and in conjunction with weight training its going to take a lot out of your system and will strain your CNS (central nervous system). If you train with a lot of volume (like myself) it wont help out with your recovery! However, if you’re on a moderate to high carb diet (gaining muscle) – HIIT can be very beneficial. Not only may it actually help build muscle over time, it also boosts the metabolism in a way that LISS cant. HIIT is also very easy to fit into your training schedule at 15-20 minute duration compared to 30-60 mins of LISS. For HIIT, I’d recommend a 20g serving of whey, around 6g of BCAAs and a serving of fat burners (stimulant based) beforehand.
LISS for Recovery
Now lets get started on LISS; yes it’s boring and very repetitive but let’s look at the benefits. First of all LISS is proven to help you recover quicker. Have you ever had incredibly bad DOMS after a leg workout that lasts for days? Try a 30 minute incline walk on the treadmill and strangely enough you’ll feel better. This is due to the blood transporting nutrients into the legs. You probably wouldn’t recover as efficiently sitting on the couch all day! LISS also utilises more calories from fat than HIIT does. To be exact LISS takes 65% of calories from fat compared to 50% From HIIT. It’s also possible to do LISS more often that HIIT. You could never really do HIIT 5-6 times a week, whilst with LISS this is possible. The best way to do LISS is by monitoring your heart rate and trying to keep it between 120-140 bpm, the so-called “fat burning zone” as studies show that at this intensity fat is the primary energy source. Burning fat is what most people want from cardio. If a heart rate monitor isnt possible try the talk test, if you can hold a conversation whilst performing cardio your doing LISS! For LISS, I’d recommend 6g of BCAAs before and a serving of fat burners beforehand.
I have experienced both forms of cardio during my dieting phase and personally I prefer LISS. I know for a fact that my body wouldn’t be able to cope on the low carb diet whilst doing HIIT 6 x per week, twice a day! I can, however, manage this frequiency with LISS and found it really increased my fitness. As you can see by the picture I managed to keep my muscle mass following a period of LISS training and the afore-recommended supplement protocol. During the first 6 weeks of my diet I performed HIIT once a week on my ‘rest’ day and I personally found it interfered with my recovery.
All forms of cardio can be beneficial, some are just better than others. If your on a surplus diet, go for HIIT once or twice a week. If you want to burn fat stick to LISS. If the body adapts add a HIIT session in there now and again. Just make sure you take your essential amino acids before any form of cardio!
Eat smart, train hard and let the results come!