Butt wink at the bottom
Pelvis tucks under at depth; lumbar rounds under load.
Overactive muscles
HamstringsHip flexors
Corrective work
Foam RollHamstrings↗Foam RollHip flexors↗StretchHamstring stretch with strap↗Squat · Lower Body
Hack Squat (Machine)
Coaching cues
- Back and shoulders against pad; feet mid-platform
- Descend to 90° or below — full range
- Drive through whole foot; knees track over toes
- Don't lock knees at the top — keep tension on quads
Common faults 3
Knees cave inward
Valgus collapse on the drive phase.
Overactive muscles
Adductor complexTFL
Corrective work
Foam RollAdductors↗Foam RollTFL↗StretchButterfly adductor stretch↗Heels rise off the platform
Ankle mobility deficit; weight shifts to toes.
Overactive muscles
SoleusGastrocnemius
Corrective work
Foam RollCalves↗StretchWall calf stretch↗