Every video needs a description, and Basecamp will not let you skip it. This is what the field is for.
What the description is
Basecamp states it plainly: this description is the video's accessible alternative, not a summary. A blind or partially sighted client has it read aloud by a screen reader instead of watching. It is the only record of anything spoken.
It is not a caption under a video. For some of your clients it is the video.
How to write one
Describe how the movement is performed, not just its name. Basecamp's own example sets the standard: "Stand with feet hip-width apart, hinge at the hips with a neutral spine, and lower the weight until you feel a stretch in the hamstrings."
Notice what that does. Setup, then the movement, then the cue for how far to go. Somebody could perform it having never seen the clip.
- Start with the setup: stance, grip, equipment, body position.
- Describe the movement in order, as it happens.
- Say how the client knows they have reached the end of the range.
- Avoid anything that only works visually. "Like this", "as shown" and "about here" mean nothing read aloud.
Why Basecamp rejects short ones
Write "Romanian deadlift" and Basecamp asks you to describe the movement itself, not just its name. Someone who cannot see the video should be able to follow along. There is a minimum length, because a name on its own describes nothing.
It takes a minute to write, and it is the difference between a video somebody can use and one they cannot.
You can fix one later
Descriptions can be edited at any time from your video library, and the same rule applies then as at upload. An old clip with a one-line description is worth going back for.
It helps sighted clients too
A written description is readable in a loud gym with no headphones, searchable when you are looking for the right clip, and re-readable between sets without restarting a video.
Captions do a different job
Captions come from your speech, automatically, and serve clients who cannot hear. The description serves clients who cannot see. They are not substitutes for one another. A silent video still needs a description, and a well-described video still benefits from narration.
A clip with no speech on it carries a No sound badge in your library. That is expected on a silent demonstration, and a reminder that the description is carrying the whole instruction on its own. Uploading a video covers narrating as you film, and Managing your video library covers the badges.