What hip rock is
Seen from behind, your hips dip from side to side on the saddle as you pedal.
Each hip drops as its leg reaches for the bottom of the stroke.
Why it costs you
Rocking spends effort on moving your body instead of turning the pedals.
It can also make the saddle less comfortable on longer rides.
Which way to adjust
The most common cause is a saddle that is a little too high, so check that first.
If saddle height looks right, smooth, steady pedalling in a slightly easier gear often settles the hips.
One check to try
- Pedal steadily for a minute, filmed from behind.
- Watch whether each hip drops at the bottom of its stroke.
- Lower the saddle a little, ride another minute, and film again.
How to film it so Llyr can read it
Stand your phone behind the bike at about saddle height, centred on the bike, with your whole body in the frame.
The rear view shows both hips on the saddle. Pedal steadily for at least thirty seconds.
Already have a clip? You can import a video you filmed earlier instead. Read the full filming guide.
What you see in Llyr
When your hips rock on the saddle, stroke after stroke, Llyr names it Hip rock and shows it on a still from your own video.
The cue to take into your next ride is Quiet hips on the saddle.
Llyr is a second set of eyes, not a professional bike fit. Check each correction on the replay, and if a fitter sees it differently, go with your fitter.