Is HIIT(High-Intensity Interval Training) better than steady cardio LISS (Low-Intensity Steady State training)? There are three main benefits to exercise and HIIT or high-intensity interval training uniquely provides. In the first place, what's the purpose? Why is exercise necessary for human health to optimize human health? Well, we can look at it in three different ways. The first and primary benefit of exercise is that it stimulates the brain and movement stimulates the brain. So this is dancing or stretching or playing tennis or tossing a ball. All those things activate your nervous system there involve coordination and movement. So that's the primary purpose of the exercise. The second purpose is circulation. It increases circulation. You increase your heart rate. You increase the output of the heart. So the increased heart rate multiplied by the increased heat output. How much it pumps with each heartbeat means that even something like walking where you might double your heart rate you might actually increase your heart output, blood flow, and your circulation many times more than that. HIIT increases circulation What does the circulation do? The blood circulates more and faster reaching more cells. It means that you're delivering more nutrients and you're taking more toxins away. That's called drainage and that's very healthy and that's part of detoxification. It's part of staying healthy and it eliminates waste products. The third thing that a lot of people kind of miss is that exercise is stressful and that can be a good thing and it can be a bad thing. So without stress, our bodies would continuously degenerate. They would just get weaker and weaker until they just fade away and die. Stress is absolutely necessary. It's the only reason the body has to respond to anything to grow and get better. How Body Builds Muscle? So think about a muscle. If you lift some weights you build some big strong muscles and then you hurt yourself. You sprain the wrist you put your arm in a cast you break a bone then a couple of months later when that cast comes off there is no muscle there because you didn't activate it. You didn't put any stress on it. There is no reason for you to maintain that strong muscle and the body says hey it must not be important I'm not gonna send precious resources to rebuild that muscle when it obviously has no use. So everything in the body has a purpose. There's a reason it's there and we have to stress it a little bit. So high-intensity exercise has the purpose of stressing the body. It's a challenge. It's a reason for the body to become more. If we don't push the limits ever then the body is very comfortable and there may not be anything wrong with that if you're just content walking and creating some circulation. Then that may be enough for you but there are tremendous benefits to high-intensity exercise because in order for your brain in order for your nervous system to repair in order for your nervous system to learn. Learning involves making new synapses. There are tremendous benefits to high-intensity exercise Growth Hormone Plays A Vital Role When nerve cells connect to each other they create synapses and what's called neural networks and the same process is involved with repair and rebuilding. So they're kind of the same thing learning and repairing. There are two hormones that are required. They're called human growth hormone and brain-derived neurotrophic factor. Don't worry about the name it's BDNF. These two hormones aren't necessary they're essential for the brain to make new synapses. They have also shown very recently that with enough of these two hormones and enough of a challenge, your brain can actually make new brain cells altogether. Not just synapses but new brain cells. They have found that it can make those in the areas of the brain responsible for memory. That's a major concern for a lot of people as they age they lose their memory. Well, there is now a known mechanism that you can restore some of those cells. It depends on human growth hormone and brain-derived neurotrophic factors. How to Produce More Hormones? The number one thing to produce more of these two hormones is high-intensity exercise but you have to really really challenge your body. You have to do something. You have to push your body to failure. So if you're doing push-ups or you're doing squats or you're doing a high-speed stationary bike you have to do it as if your life depended on it until you fail because then your body says hey what I did this time wasn't good enough. I need to get better. I need to become more so I can handle this challenge next time. And it produces as much as 3 to 400 % more of these hormones. These hormones are so powerful as rejuvenating hormones that they're often given to the elderly as a way of restoring their health. The problem is when you add it from the outside when you give it as a drug it has side effects and it has the potential of increased risk of cancer. If you do it naturally through exercise there are none of the side effects none of the ill effects. You only have benefited from it. Don't Overdo It The thing to keep in mind with the high-intensity exercise also is that because it is so incredibly stressful you don't want to do much of it. You want to do enough that you create a challenge but not so much that you break the body down. Remember exercise breaks the body down then recovery allows the body to rebuild. So if you break it down too much then it doesn't have the time and the resources in between workouts to recover and rebuild. So the key to high-intensity exercise is to increase gradually so that you know that your body's health and your physical shape can tolerate it. Don't go right into just all-out. You build up and make sure that your body can tolerate it and you check with your physician if there are any contraindications or any reasons why you shouldn't be able to do that. When you do it you can do as little as 5 or 10 minutes. There are different programs you can check. Some of these workouts you can do in as little as three or four minutes. If you include warm-up you might spend 10, 15, or 20 minutes but the active time that you're doing this should be just a couple of minutes. So that also makes it very time efficient for people who don't have a lot of time to exercise. You don't have to have hours and hours. You have 15 minutes you can do it oftentimes and you won't even break a sweat. 2 To 3 Times A Week Is The Sweet Spot Because it is so brief and you also don't need to do it very often because once you trigger that growth hormone to 300 or 400 % increase it stays high for up to 48 to 72 hours. It declines gradually but even 3 days later you're gonna have some residual increased level of that growth hormone. You don't want to do it more than 2 or 3 times a week because it is very stressful. The benefits stay with you for several days. Another nice benefit for people to know is that growth hormone is a fat-burning hormone. So even though you don't exercise for a very long time and you technically don't burn all that many calories during the workout. You burn much much more energy much much more fat for fuel in the days after the workout because you increase your metabolism and you're increasing this growth hormone.