Babies don't usually start to stand on their own until they're nine or 10 months old, but an Icelandic swimming school is helping juniors leap ahead of their peers.
At a pool in Reykjavik, development therapist Snorri Magnusson gets babies as young as three-and-a-half months old balancing upright on his hand or a board.
Parents bring their bubs for one-hour classes, twice a week, for 12 weeks. They also have homework.
"But it always starts with the [straightening] training... Because when there is strength in the spine and the upper body you can do whatever," Mr Magnusson says.
"The parents are always very surprised, really surprised by what their babies are able to do."
At the end of his latest course, 11 of the 12 babies enrolled were able to stand on their own for 15 seconds. The remaining could only stand for eight seconds unsupported.
Mr Magnusson says the infants aren't just ahead of the curve when it comes to standing, but are sometimes the first to start talking and smiling too.
At the course the babies start with warm-up exercises, being encouraged to reach and grab objects, helped by their parents.
Mr Magnusson then gets the babies to somersault on a floating mattress, before holding them on top of his balm and the baby stands.
He says despite being at a pool, what he offers isn't a swimming school.
"I am not here teaching babies how to swim. I am working with their motor development, working with their balance," he says.
"That is the foundation of my work. I am not teaching them how to swim."
The class has gained attention from neurologists and paediatricians.
Earlier this year, Norwegian neuropsychology professor Hermunder Sigmundsson studied the class, while Spanish paediatrician Juan Ferrer de Paula says he's baffled by the feat.
"I would like to know how this man can stimulate these babies so they can stand on their own. It isn't logical. It isn't normal.
"But to watch them standing on their own on top of the palm of his hands is something extraordinary."
Prof Sigmundsson's study suggests the babies are forming neural connections at an early age, helping them do things earlier than previously thought.
The study's authors acknowledge it was only a small group of children, around a dozen, who were examined.