The 20 Challenge

Wednesday, August 13 2025

Turn the power button on in your classes and let the challenge begin with the latest Fitmotivation video, 20 Water Exercises. Taught deep or shallow, this 50-minute class template features 20 aquatic fitness base exercises for total body results, including 5 cardio, 5 lower body, 5 upper body and 5 core. Once all 20 are introduced in the beginning of class, its Game On. The 20 moves get recycled several times in both aerobic choreography and HIIT segments.

 

 

Designed to show that less can be best, the inspiration for this video comes from my own experiences as an instructor. This summer, I am celebrating my 30-year anniversary as a group fitness instructor. During my early years of teaching, I would create routines that were jam-packed with a variety of innovative moves and combinations. My mission was to invent moves never before seen in the world of aquatic fitness. Fearful of boring my students to death, I instead caused frustration and confusion. The fancy routines I created caused mayhem in the pool because they were too complicated to follow. The endless efforts to dazzle my students with showstopping choreography did nothing except burn me out.

As a seasoned instructor, I now preach the benefits of basic moves, fewer exercises and the repetition of movement. Utilizing fewer moves and repetition of those moves in a class makes routine design much easier on the instructor. Moreover, it allows the student to master the form and achieve better results. As an avid gym patron since 1988, I can testify that we would never do an exercise in the gym without repeating it for several sets. Likewise, the same cardio exercise is typically done for 30 minutes or more. Yes, people who attend group fitness classes often do so because they find self-directed gym exercise boring. They attend group fitness classes in the hope that the instructor will add some cherry flavor to the chore of exercising. However, I think if class members were given the choice of results versus cherry flavor, most participants would choose results.

In creating 20 Water Exercises, I wanted to prove that you can still add cherry flavor on to the repetition of exercises, making the experience both effective and engaging.
Below, I talk more about my inspiration for the video and then read on for a summary of the class action.

 

 

POOL WORKOUT-AT-A-GLANCE
The 20 Water Exercises video includes a warm-up, cool down and 6 exercise segments. This class format can be instructed in both deep and shallow water. There is no equipment required. The water’s resistance is plenty.  However, a deep-water flotation belt should be worn by class members in the deep end.
Segment 1:  20 Water Exercises
The 20 water exercises are instructed for the first time. The 20 exercises are broken into four categories, with 5 cardio exercises, 5 lower body, 5 upper body and 5 core. In this segment, exercise is taught linear and timed for 30 seconds each. The energy expectation for class members in this segment would be around a 6 or 7 out of 10 on the Rate of Perceived Exertion (RPE) scale.
Segment 2:  4-Move Aerobic Combos
The 20 water exercises are now showcased in aerobic choreography, with five 4-move combinations. Each combination includes a cardio, lower body, upper body and core exercise. Creating the combos was made easy by using all the #1’s in each category, then the #2’s, the #3’s, the #4’s and the #5’s. Putting the moves in combinations creates a more engaging experience for class members. However, as demonstrated in the video, smooth transitions need to be considered as the moves were not designed to go together. When a transition is needed, a simple “bounce/land center” on the last one or two music counts usually suffices. The energy output here would be aerobic, a 6 or 7 RPE out of 10.
Segment 3:  2-Move Aerobic Combinations
The 20 water exercises are recycled once again, this time in ten 2-move combinations. The pace is brisker, a solid 7 RPE out of 10. Once again, smooth transitions need to be considered when combining two or more moves. The video demonstrates these transitions. By the end of this segment, class members will now have been exercising aerobically for 30 minutes.
Segment 4:  AMRAP
The intensity goes way up as the action transitions from aerobic to anaerobic. AMRAP, a form of high intensity interval training (HIIT), stands for “As many reps as possible.” This segment uses up four of the 20 exercises, one cardio, one lower body, one upper body and one core. Each exercise is instructed for all-out intensity for 30 seconds, followed by 15 seconds of rest. This is then repeated a second time. The goal is to have your class members count their reps in both rounds and try to beat their first score by at least one rep. The energy expectation in this segment and the next segment is an 8 or 9 RPE out of 10.
Segment 5: Tabata
Tabata is another HIIT format and subscribers should be familiar with it by now because it has been featured in many Fitmotivation videos. In this segment, 8 more of the 20 exercises are used in the Tabata round. Each of the 8 exercises is performed for 20 seconds of very high intensity, followed by 10 seconds of rest. Segments 4 and 5 are the intensity peak of the class and should be cued to remind students of that.
Segment 6: 8-Move Aerobic Combo
After incorporating 12 of the 20 exercises in segments 4 and 5, the remaining 8 exercises are used in an 8-move aerobic combo. After the heart pounding intensity of the previous two segments, this 8-move combination serves as more of a cool down as the energy expectation decreases to a 6 RPE out of 10. This decrease in intensity helps transition the class to the final stretch.

So yes, 20 Water Exercises is much more than just 20 exercises. My goal was to help aquatic fitness instructors simplify the process of routine creation by utilizing fewer moves. I hope you enjoy this class and that you embrace repetition in your classes, discovering that less truly is best.
Below, Ron brought his daughter Alice as a camera assistant. Alice was an infant in a crib when Ron and I started filming Fitmotivation videos together in 2014.


On the set of the new Fitmotivation video, 20 Water Exercises

Author: Mark Grevelding is the founder of Fitmotivation and Poolfit. He is also a training specialist and consultant with the Aquatic Exercise Association’s (AEA). Mark has been active in the fitness industry for 30 years as a group fitness instructor, personal trainer, international presenter and a continuing education provider for fitness professionals.