When it comes to cardio there are two different forms of which an individual can utilize; LISS (Low Intensity Steady State) and HIIT (High Intensity Steady State). During this article I am going to breakdown what HIIT is, the benefits of HIIT, differences in cardio exercises, and routines you can utilize when it comes to HIIT Cardio. A lot of people tend to believe HIIT is far superior to LISS when it comes to cardio and the best bang for their buck. While that can be said about anything in diet and training on what is more optimal everything has its own place and time depending on the situation at hand.
What is HIIT Cardio?
HIIT stands for High Intensity Interval Training meaning that you are going to do high intensity in short little intervals or bursts. To set this up a client or gym trainee can go about it in many ways. They can split up their intervals into different time blocks on how they want to perform them. Many individuals like to stick to a 15 second interval limit with a 45 second cooldown.
Example:You would ride a bike at a very low speed as a cooldown for 45 seconds and then crank it up to about level 15-20 in resistance and pedal as fast as possible for that 15 second interval. Lower the device back down to 1-2 and then repeat the process in that fashion. This is what most refers to as the high energy phosphate system where you are doing quick bursts of energy. This will also activate ATP (Adenosine Triphosphate) levels which can raise and aid metabolic change.
While some like to stick to the shorter durations of HIIT Cardio, others like to start and use higher intervals upward to 30 seconds or even 1:30 seconds. Now if we think about that for a second, how can an individual go all out for such a long duration of time? Also what would the benefit be behind that and trying to go at a sub-maximum amount of intensity for a longer duration? If we think for a second this is still a way to overload your muscles, and also aid with fast twitch muscle fibers and breakdown muscle to a degree. This is referred to as the Anaerobic Glycolytic System.
Example: You would be moving on an elliptical at a 30 second cooldown and 30 second interval phase (all out). Another would be would 1 minute ON and 1 minute off (off meaning cooldown and ON meaning Interval). I have also seen people go upward to 1:30 Interval or even 2-3 minutes.
LISS and HIIT
The alternative to HIIT is LISS (Low Intensity Steady State) like we talked about in the Aerobic Oxidative System which is when performing exercise at a low intensity. Due to this you are tapping fat reserves instead of using glucose or carbs which is the primary fuel source when using HIIT Cardio. You will not get the benefits of ATP to the higher degree that HIIT does, and the amount of lactic acid production is minimal when performing LISS.
Research by Dr. Layne Norton which shows that long bouts of LISS over prolonged periods of time can:
- lower metabolism
- blunt hypertrophy
- far less optimal for fatloss
- limits muscle growth
LISS and HIIT both have their place and time, but lets look at some benefits to HIIT. When we look at research this is what we have learned. We also have noted that even when dieting, or in a growth phase, keeping your metabolic rate elevated can also aid your current muscle mass and retaining mass when in a caloric deficit. Hence why HIIT may be superior over LISS in a dieting phase (dependent on diet). Those on a keto or low carb diet may thrive off LISS (i.e. a Dave Palumbo Keto Diet).
Some examples as we now understand a bit more relating to HIIT could vary on what equipment you have and what you do enjoy. Most people will not enjoy HIIT the first go around because of how demanding it is, and how much it will push your buttons to an uncomfortable level.
The most common HIIT is done on an exercise machine in a typical gym session. I personally enjoy using an upright bike or an elliptical machine. The reason why is because this is the easiest way and quickest to change the resistance. A treadmill for example may take you a good 15-20 seconds to get it to full blast, while on a bike holding down the resistance button or an elliptical takes seconds to get it to full blast. If you have a modified wingate or a spin bike then you can also turn the knob for the resistance in a matter of two seconds to really make it fast on the change in resistance.
Another form that I like to utilize would be doing track sprints. Instead of being on a bike or an elliptical you can go out on a track or up a large hill and sprint. This would be similar to the very short interval format of 15-30 seconds and then a 45-30 second cooldown. While depending on the track or the hill you do this on it could vary, but this would be a great option to see if you can push yourself to sprint harder each and every single time. I personally enjoy doing 110 yard dashes or 100 yard sprints when I have the luxury and weather. Living in the north east that usually does not happen often besides the summer months and even then the weather can be a far stretch.
Sled Drags and Parachute Sprints
While you are out on the track another thing to consider would be sled drags or parachute sprints. I really like loading up a prowler with some weights from a local gym and then pushing it on a football field or in a nearby parking lot. When doing sled drags I would personally opt for a shorter interval like 15 seconds when pushing and giving it full intensity, the same would be said with a 100/110 yard dash. You will not likely take more than 15 seconds or so to complete the dash. When you are done continue to walk around the track and continue your sprint if you want to count in your head for a 45 second cooldown or prolong it to a 1:45 second cooldown which may take you back to your starting position. The same would be done with the parachute. Put the parachute on and do a sprint for a good 10-15 seconds. Honestly if you are going 100% this will make your legs feel like they are on fire, dispatch the parachute and walk around the track, put it back on and rinse/repeat for a good 10 intervals and you will be drenched in sweat.
While we are on the topic of parking lot one of the hardest I have seen done especially by Dr. Norton again is car pushes. While this may sound bizarre this is not for the weak. I would highly suggest not trying this right out of the gate because of the demand on your legs and how hard it will be to move a full force car. I would suggest bringing it to a parking lot and putting it in manual or neutral so you can still move the car even on your own willpower (turn key forward, put on neutral, turn off, lock steering wheel). Give yourself plenty of room because it will be hard to move and in case anyone else does drive around you which may distract you during an interval.
Again with how heavy and hard this is keep the intervals down to 15 seconds max starting out and try to increase to 20-30 seconds after a few weeks or even a month because of the demand on your legs and hamstrings. Depending on your car (say a truck vs a small sport car) will vary in difficulty. You are talking a difference in thousands of pounds you are trying to push. While the car may not move far, it will honestly be one of the harder things you do encounter.
Boxing and Kettlebells
First of all boxing as we know is very short in duration for each round and causes an incredible workout. I would personally avoid an upper body workout day when doing the boxing or punching bag because of the demand and stress on the muscles of the upper body. I would avoid a lower body workout day for the Kettlebell workout (KB) because the swings you will do will activate your core, hamstrings, and glutes to another degree and will leave them sore. Again for both of these keep them short to start especially boxing, once you become accustomed to hitting the bag over time you may be able to stretch the interval to one minute, and give yourself a good 1 minute cooldown or even 2 minutes before starting back up again. The same could be said with KB swings; the amount of stress and strain on your legs (if you were to do legs prior) would be too much. This would also take away from overall recovery.
When doing a swing you want to make sure the range of motion (ROM) and also locking out at the top to get the full degree and tension on the muscles while also elevating your heart rate to a great degree. The Journal of strength and conditioning has even done a study on KB Swings showing the effectiveness of the fast twitch muscle fibers which could lead to muscle growth for the short bouts of intensity intervals.
Find What Works
Whether you are on a fat loss phase or a gaining phase will alter the amount of times you will perform HIIT Cardio. While I like to keep cardio to a minimal regardless of goal and let your diet dictate the change in your appearance and training because that is what fuels our body.
For bulking I would suggest 2 short 5 interval sessions a week, and for those dieting you could start at 2, but may need to increase upward to 5 sessions towards the very end of a contest prep or getting ready for a photo-shoot trying to torch off the last little bit of fat, but again diet will be key behind the changes and manipulation of cardio. The amount of research is really in favor of HIIT and with that said I just want to touch on a couple studies before I do close the article.
Metcalfe if you search this via pubmed will show you that doing HIIT 3x a week for 10 minutes compared to individuals doing LISS for 40 minutes. In the end of the study those who performed HIIT increased their fat burning potential and increased their insulin sensitivity.
During his study interval training increased skeletal muscle, an increase in carbohydrate and fat metabolism burning during exercise. There was also improved changes to body composition when performing HIIT cardio at least 2-3x a week for 10 minutes.
An individual who did a research study on HIIT cardio for 20 minutes were similar results of study number 1 with Metcalfe in reductions in bodyfat, reduction in insulin levels, and overall less fat in individuals leg fat and abdominal fat.
While these may not be all the HIIT workouts these are a good majority of them to get you working in the gym and starting to understand how drastic and hard HIIT cardio truly is. Doing so will help the individual reaping the benefits of the cardiovascular exercise and getting them to help achieve their goal to a faster degree with the aid it offers.