Resources Library

ePublication of Australian Fitness Network

By adapting HIIT to the dynamic aquatic environment, you can give your participants a superb workout that’s high in intensity yet low in impact.

There’s a reason that high intensity interval training has been the industry trend of recent times: it’s very effective at igniting cardiovascular and metabolic benefits, including improvements to insulin sensitivity and reduced blood pressure. The downside, for some, is that high intensity also sometimes equates to high impact. Water exercise offers a protective environment with reduced impact, functional core strengthening and mobility benefits. Combine HIIT with the pool and you have a marriage made in heaven!

The pressure and resistive forces of water (hydrostatic pressure) aids venous return (blood flow back to the heart), which results in an increase in stroke volume. This effect decreases heart rate even though the exercise intensity is at a peak level. This decrease in heart rate and rapid recovery time makes water-based HIIT suitable for a range of participants.

Measuring intensity

The scale or rate of perceived exertion (RPE) is a simple and effective way to gauge intensity. Aqua classes are often attended by a range of participants with varying fitness levels and for this reason it’s best to empower them to monitor their own exercise intensity. While heart rate monitors are now waterproof, instructing participants to measure the exercise intensity subjectively, on a scale of 1 to 10 (where 1 is no effort and 10 is maximal effort) provides a simple and quantifiable personal motivational skill.

Accurate work bout-to-rest ratios

Several online music providers or apps offer options to include an interval timer into music tracks – check out ‘HIIT interval training timer’; ‘Interval Timer – Timing for HIIT Training and Workouts’; and ‘Seconds – Interval Timer for HIIT, Tabata Training’, for starters. The benefit to you, as the instructor, of using music or an app with set timed ratios is that it allows your focus to remain on the observation, analysis and modification of the exercise technique rather than clock watching.

Instructor motivational techniques

Just as participants exercise at different intensities, so too do they respond to different motivational techniques. Because HIIT training requires participants to exercise for short, high intensity bursts, they may need additional encouragement to maintain the level of effort over numerous bouts. How they like their motivation dished up, however, will vary.

While some may respond to drill sergeant-style instructors yelling ‘give me 10 more’, and others might prefer instructors who compete with them to ‘show them how it’s done’, the ‘ideal’ instructor encourages, inspires and sets realistic work bouts to gain the most effective physiological and biomechanical outcome for each participant.

Just remember that although HIIT is, by its nature, highly intense, it doesn’t mean that your vocal motivation has to mirror it: yelling louder doesn’t result in participants exercising more effectively or efficiently. Voice projection within a busy, noisy and often humid environment, such as a pool, is often a challenging instructor skill in itself. If you can get the necessary volume and delivery without sounding harsh or aggressive, you’re well on your way.


Try one of the following HIIT-style formats in your aqua classes, and then experiment with the others as your confidence in the format grows.

Format 1: Partner Tabata/competitive training

This Tabata training protocol involves performing a particular exercise at the highest intensity for 20 seconds, followed by 10 seconds of recovery. This is repeated for 8 sets, totalling 4 minutes duration.

My class participants enjoy the competitive nature and social connection of this format. The short burst of effort encourages the ‘competitors’ to achieve personal bests with absolute warrior determination (competition) and immediate feedback from their partner (social connection).

An example of a 20-second Tabata interval might see partner 1 performing mermaids and counting the total number of repetitions they complete in the set time period, and partner 2 treading water at the highest intensity, lifting the chest out of the water.

At the end of the first interval, partner 1 informs their competitor of their result (the number of repetitions), which then becomes the target for partner 2 to match or beat as they proceed to swap exercises. Exercises are alternated between partners for each interval over the 8 sets. Attempting to match or beat the number of reps is the name of the game for the aqua partner Tabata format.

When it comes to designing Tabata aqua exercise combinations, aim to select a move or sequence that elicits the highest heart rate. As we know, aqua exercise intensity is dependent upon a range of variables, including water depth and temperature, lever length and water turbulence, so the best way to figure out which moves work best for aquatic HIIT is to try them out.

However, to get you started, you may want to consider the following moves, which are high enough in intensity and can be counted easily: plyometric stars, fast and powerful rock’n’roll, and Murray rivers are most appropriate for the moderate/high intensity exercises performed by partner 1, while weighted moves such as intense long arm chest press or ski arms are suitable for partner 2.

Format 2: 50/10

This format features 50-second work bouts followed by 10-second active recovery, and is effective in both shallow and deep water.

Our aqua instructor training tells us that travelling in the resistive forces of water will elicit higher oxygen consumption when compared with stationary exercises. Longer and larger limbs will also create greater friction and water turbulence than shorter and smaller limbs and thus will also affect the movement of the body and intensity level of moves during deep water travel.

Examples of moves to use during the 50-second work bout (with or without a flotation device) include:

  • Side flutter travel
  • Supine seated travel
  • Rock’n’roll travel.

Examples of 10-second active recovery moves include:

  • Seated long arm press
  • Rock’n’roll stationary
  • Big Ms.

Format 3: 30/20/10

This format comprises three progressive intensity work bouts of the same move with variation in delivery. Each bout increases with intensity and does not allow for any rest period for a total workout period of sixty seconds. As a more challenging HIIT format, you should be very mindful of whether it is suited to your participants. The concept features:

1. moderate exercise intensity for 30 seconds (allowing the mind and body to familiarise with the movement pattern)
2. variation of the move to increase intensity for a further 20 seconds
3. warrior workout zone for the final 10 seconds (suspended move variations are good for ramping up the intensity).

You should then be ready to instruct the next sequential movement pattern of 30/20/10-second bouts.

An example of three 30/20/10 sequences could look like this:




Your participants may not be ready for HIIT sessions to replace their regular aqua classes, but you could certainly introduce the concept, either as a section of a regular class, or by alternating with your usual format.

Offering this sort of diversity in your aqua programming will not only keep you inspired, it will also encourage participants to return for more – especially when they start to reap the rewards of the aquatic HIIT workout.

Christine Naysmith presents the AUSTSWIM WETS Aqua Instructor Course across Australia and New Zealand and works behind the scenes in course development. A popular group fitness instructor, she uses her background in drama and education to keep participants entertained and on their toes!

Member Only Content