I suggest getting paid for your work and not “partnering” with an instructor that “has a killer local following and she should sell a DVD.” As with most (not all) partnerships like this, you bear the brunt of the cost and they do the marketing and sales and…. you know the story.
I did one aerobic video years ago – got horrible reviews as I searched online years later! Not anything with production value (of course) but fitness is a killer market. Viewers hated the “old warehouse” look (not my call; poll your audience first) and the personality of the instructor. The participants must practice, Practice, PRACTICE! And know the routines inside and out. You and your client should spend a few days reading online reviews of the best videos out there – Sony spends upwards of $500K on a Buns of Steel video. That is your competition.
Use a wireless belt pack designed to be submersed in water; bring a backup too. Use a headworn mic with solid ear clip, also designed for wet/sweaty applications. Look at the best videos out there and use what they use. High SPL for when the instructors are yelling, maybe a different mic for the quieter, cool-down periods. They sound different at different levels. The beltpack will need to be moved many times based on the routines – side, back, brastrap, etc.
We played back music from a CD player at a quiet level in the room for the routines (so low you could barely hear it on the mic, hence the reason for the participants to know the routine) and then mixed it in later during post. Against my judgement they had one track on a cassette – this was a nightmare! Cassettes do not play at the same speed across players. Syncing later took forever. Now I’m dating myself when I did the video. Ha!
Shoot in an environment where you control all lighting – windows will kill you as the light shifts and color temp changes. Shoot at night if you have to.
I shot the segments out of order (see lighting changes above): Cool down first, then warm up stretches, gradually reaching the tough stuff last. This kept the sweat levels down and their energy decent for the 7-hour shoot day. If they have budget, shoot on a few days, lots of outfit changes, and the participants are truly committed to the gig.
We had a successful yoga video with a respected RN/Holistic teacher, same rules applied.
If I think of anything else I’ll add. Have fun & good luck!
Steve

