Benefits of HIIT

Image result for pictures of water exercise

HIIT, or high intensity interval training, is popular in all kinds of fitness formats. HIIT was named the #1 Fitness Trend for 2018 according to the American College of Sports Medicine’s world wide survey. During HIIT the goal is to work so hard that it becomes difficult to breathe in enough oxygen to supply the demands of the muscles. You are working at 80-90% of your maximum effort. Once you get to 90% effort, your body’s demand for oxygen exceeds the oxygen supply available. This is called crossing the anaerobic threshold. Your body must now rely on energy sources that are stored in the muscles. Since there is only a limited amount of energy stored in the muscles, this level of intensity can only be sustained for a short time, ranging from a few seconds to 2 minutes, depending on your fitness level. The recovery period in anaerobic exercise is important. If the recovery period is shorter than the high-intensity period, then the body is unable to achieve full anaerobic recovery. Therefore, in most cases the recovery is longer than the work.

HIIT improves both aerobic and anaerobic fitness. It has also been shown to improve blood pressure, cardiovascular health, insulin sensitivity, cholesterol profiles, and abdominal fat and body weight, according to the American College of Sports Medicine. HIIT burns more calories than continuous cardiorespiratory training, especially after the workout. This occurs because the heart and lungs work hard to supply oxygen to the working muscles and after the exercise ends, the body has excess oxygen to consume. About two hours are needed to use up the excess oxygen. This post exercise period adds around 15% more calories to the overall workout energy expenditure.

To increase intensity for interval training in water exercise you can increase the range of motion, increase the speed without decreasing the range of motion, go into the suspended position, and add acceleration by jumping or performing the exercise with power. (See my previous blog post: Make Your Heart Stronger with Intervals.) However to go into HIIT you will need to use two of the intensity variables at once, such as full range of motion with power, or speed with jumping. Try adding power while traveling. Another strategy is to work in two planes at the same time. You can do this by alternating one move in the frontal plane, such as a frog jump, with another move in the sagittal plan, such as tuck ski. A second way to work in two planes is to combine a leg move in one plane with an arm move in a different plane. Examples include kick side to side (frontal plane) with arms sweeping side to side (transverse plane); cross-country ski (sagittal plane) with rotation, hands together (transverse plane); and high kick (sagittal plane) clap over the leg (transverse plane) and under the leg (frontal plane). When you are working at 80% of your maximum effort you are able to grunt in response to questions but can only keep up the pace for a short time. At 90% of your maximum effort you will feel like you can’t do this much longer.

Since periods of high intensity are alternated with periods of recovery, HIIT provides the exerciser the opportunity to experience the extra benefits of intense exercise without creating an experience that is negative or unpleasant. However, not everyone in a class is willing or able to do HIIT. Some may have an injury that prevents them from performing certain moves. Some may have a condition that makes working at that level contraindicated. Some just may not be able to push it hard that day. For safety’s sake, participants should always modify the intensity to a level that is challenging for them rather than trying to keep up with other participants.

My book Water Fitness Progressions has information about HIIT along with sample lesson plans that include high intensity intervals with a variety of ways to configure the intervals. To order the book from the publisher, click on the title. The book can also be ordered from Amazon.com  

See you in the pool!

Chris Alexander

Make Your Heart Stronger with Intervals

The way to make your heart stronger is to make it beat faster. Since there is a direct correlation between how fast your heart is beating and how fast you are breathing, making your heart stronger means exercising at a pace that makes you breathe faster than normal. Interval training is a popular way to meet this objective.

Interval training is alternating bouts of fast paced exercise with slower paced exercise. The fast pace is called work and the slower pace is called recovery. One period of work plus one period of recovery is called a set. A group of sets is called a cycle. The chart above shows a cycle of five sets of intervals. If you are jogging, your work might be running and your recovery could be walking. In a water exercise class, your work might be performing an exercise faster, but there are other ways to increase intensity.

The basic aquatic exercises of jog, kick, cross-country ski and jumping jacks can all be performed at a somewhat easy level. Your breath will be faster than standing still, but you can still do the exercises while talking or even singing. To increase the intensity to a moderate level, increase the range of motion, that is, make the moves larger. Your breath will be a little faster and although you will still be able to talk, it will be harder to sing. To increase the intensity to a somewhat hard level, increase the speed of the exercise. Try not to lose range of motion as you go faster. For many people, taking the exercise to a suspended position is also somewhat hard. With faster moves or suspended moves you may be able to talk, but you will be breathing hard enough that you won’t really want to talk. To work at a hard level, add acceleration. This could be by jumping but you can also perform the exercise with power. The harder you push against the water the harder the water pushes back. Power moves are slower but the effort is greater. At this level, you might be able to grunt in response to a question and you will feel like you can only keep that pace for a short time.

Click on this linkhttps://youtu.be/g5V0lzwTi40 to watch a video of the basic exercise of cross-country ski in shallow water along with the variations of increasing range of motion, increasing speed, going suspended, adding power, and adding rotation (a variation of a power move). Each variation is performed for 4 counts.

Click on this link https://youtu.be/ZDJnhaxP5cU to watch a video of the basic exercise of cross-country ski in deep water along with the variations of increasing range of motion, increasing speed, adding elevation (accelerating the legs toward center to lift the shoulders out of the water), adding power and adding rotation. Each variation is performed for 4 counts.

The work period and the recovery period of an interval can last for a few seconds up to a few minutes. Usually the recovery period is longer than the work period so that you can recover fully before starting the next work period, but you can have a reduced recovery period for an added challenge. Some ways to time the intervals are:

  • Interval 30: 30 seconds of work to 90, 60 or 30 seconds of recovery
  • Interval 40: 40 seconds of work to 80, 60 or 40 seconds of recovery
  • Interval 60: 60 seconds of work to 120, 90 or 60 seconds of recovery
  • Reduced Recovery Time: 1, 2 or 3 minutes of work to 30, 60 or 90 seconds of recovery
  • Rolling Intervals: work for 1 minute, increase intensity for 1 minute, and increase intensity again for another minute
  • Surges: work for 45 seconds and increase intensity for 15 seconds to 60 seconds of recovery
  • Tabata – 20 seconds of work to 10 seconds of recovery 8 times
Chris Book Cover

These ways to time intervals, plus additional timing options, are explained in my book, Water Fitness Progressions. The book also includes sample lesson plans that use these timing options with variations for moderate, somewhat hard or hard intensities. To order the book from the publisher, click on the title. The book can also be ordered from Amazon.com  

See you in the pool!

Chris Alexander