High Intensity Interval workouts are short, intense workouts that are extremely effective for a number of reasons.First, you create more muscle mass with these workouts. Muscles play a very important role in your metabolism. The more muscles you have, the more fat you burn. Even at rest! The amount of fat for an average adult grows by one kilo a year. This is caused by a metabolism that is getting slower while we get older. 

The slowing of the metabolic rate is mainly due to a loss of muscle as we age. By getting only 2 kilos of extra muscle -and maintaining this, the average adult can completely reverse the weight gain. Muscles do not only burn more calories at rest, but strong muscles are also important while performing an HIIT.
The second reason that HIIT is so effective is that these workouts cause you to burn more calories long after the completion of the training. HIIT keeps your metabolism stimulated up to 36 hours after your workout, while at the same time restoring your body. 

These short intensive workouts train your muscle endurance (strength explosiveness) and your cardiovascular endurance (fitness) at the same time. You build muscle mass while you give your metabolism a boost. Even after your workout! 

Through HIIT, you can obtain great results with just a small investment in time. These workouts are super-efficient and can be done anytime and anywhere without the need for complex and expensive fitness equipment. You can achieve great results in the time it takes most people to drive back and forth to the gym. 

What is interval training exactly? As its name says, it is "exercise at intervals”. In other words you change the intensity continuously during your training. A few minutes at full power, and then again at an average pace. This method has four big advantages:
• Very time efficient
• Better muscle development
• More fat burned
• Faster results