can you cause injury when practicing butterfly?

can you cause injury asking swimmers to practice butterfly leg action on their backs with a woggle around them?

Hi Susan,

By only using a woggle (small and flexibile float) I think you'll be ok and won't injure your swimmer's back, however, I think it might be better for them to practice this technique on their side or their front (with a float in front).

I've attached some Butterfly Tips I found using the drills search bar (top right).

Hope this helps,
Alex