HIIT is an awesome training strategy to maintain appearance and high cardio-respiratory function. It can be performed with a multitude of exercises and it focuses on keeping your body moving. HIIT involves lots of circuits which involve two or more different exercises. These circuits usually consist of opposing muscle groups so you can keep on going without stopping. This type of training is an excellent way to burn fat, build muscle, and keep your heart and lungs in peak performance.
        
A good example of athletes that uses HIIT are short distance sprinters. Short distance sprints primarily use the ATP-CP system for energy and glycolysis. By using this type of training your body avoids going catabolic (muscle wasting-using own muscle for energy). If you want to have a nice lean and toned body you need to have some muscle on your skeleton. If all your doing during your workouts is going on long runs this will not help you look aesthetic.  
     
HIIT can be applied to running, weightlifting, and swimming! Depending on what type of activity you are doing, you should create a different program for yourself. I will stick to running and weight lifting, because those are the two that I know the most about.

When your using weight training or sprints within your workouts to keep your body at a high heart rate you are getting the most benefits. A high heart rate means that you are both training your aerobic capacity (heart and lungs) and your anaerobic energy systems. It also means that you are burning a ton of calories!  Anyone can make a high intensity interval training program for them self. The trick is to make a program for yourself that will give you the results that you are looking for. You want to use "circuits" in your training. A circuit is a set of two or more different exercises. They usually take the form of push/pull, upper half/lower half exercises, etc. You want to fatigue one group of muscles and then let them rest but keep your heart rate high by working a different muscle that hasn't been worked yet. Here is an example:

You have a vacation in 2 weeks and you decide to get on a diet and shed off those last few pounds. You need to figure out, "What can I possibly do during my workouts to maximize my results?" You decide that you want to create a circuit for yourself that uses upper half/lower half exercises to keep you at a high intensity. Here's how the circuit would look like: 

1. Dumbbell Chest Press- 12 reps
2. Wide handed push-ups- until failure
3. Barbell Squats-12 reps
4. Body weight explosive jump squats- until failure
5. Rest 30 seconds to 1 minute.............. (That is one set, now you need to repeat it two more times)

This type of circuit is designed to keep you moving. The only hard part is choosing what exercises to use and what order to do them in, which isn't even that hard. Depending on your goals I'm sure you will be able to figure it out. You can do circuits for any muscle in your body. Here is another example of a circuit that I have done during my workouts to burn some fat off and target my abdominal muscle:

1. 50 crunches
2. 30 abdominal bicycles
3. 1 minute Plank
4. Mountain climbers
5. Sprint 100 yards
6. Rest 30 seconds to 1 minute.......(That is one set, now you need to repeat it two more times or MORE!) 

Some benefits of High Intensity Interval Training

1. Your workout sessions will be more efficient. You can burn the same amount of calories in 15 minutes of HIIT compared to 1 hour of traditional weight lifting.
2. The longer you continue doing the circuit for the more your body will rely on its fats for energy. First it mostly uses its glycogen (sugar) stores, then it slowly switches over to fats.
3. You will have a healthier heart and increase your aerobic capacity!
4. If you do it right, there is no equipment necessary!
5. If you want to get toned before summer, running is not the best way to lose fat, because you might also lose a bit of muscle if your diet is not perfect. HIIT training has been proven to have a smaller likelihood of making your muscles go catabolic.
6. During intense bouts of exercise your body produces human growth hormone (HGH) at higher levels, which ultimately may have an anti-aging effect and help your body look lean with less fat.
7. "Benefits include improved serum lipid profiles, blood pressure and inflammatory markers as well as reduced risk of stroke, acute coronary syndrome and overall cardiovascular mortality." Aust Fam Physician. 2012 Dec;41(12):960-2.

If you need help with designing a HIIT program for yourself I am more than willing to help for free. Yes that is right, I said it! I don't want your money. I'll help  you either way. But you are more than welcome to donate, which will definitely help run this site. If you do contact me please use this format. Thank you. 

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