A teenager has been charged with serious assault after allegedly filming another teen crash tackling a 72-year-old woman to the ground in an unprovoked attack on the Sunshine Coast.

If convicted the 19-year-old faces a maximum of seven years in prison, the same sentence the 18-year-old who allegedly physically targeted the woman is facing.

Police allege the pair were part of a larger group of young men who were on Alexandra Headland before dawn on December 27, when the woman was in the midst of her usual morning walk.

Detective Senior Sergeant Daren Edwards said it was an alarming attack.

"She was walking along when she heard someone running up behind her — she just thought it was someone jogging," he said.

"Unfortunately one of those males, after being egged on by his counterpart, tackled the woman on to the sand and she did hurt her knee.

"She was obviously quite alarmed and stunned, she had no-one with her. It was quite distressing for her."

After making a formal complaint, police were able to identify a phone that was used to film the attack as part of a separate investigation.

Once discovered, that footage allowed officers to identify suspects and lay charges.

Detective Senior Sergeant Edwards said the 19-year-old is facing the same charges, even though he allegedly had no physical role in attacking the woman.

"We'll allege that he counselled and was part of the offence by counselling and encouraging that offence to occur."

"A young man running and tackling a woman from behind, the injuries could have been much, much worse and severe."

The age of the woman and the nature of the attack means the charges are more severe than common assault.

The two men are due to face court in Maroochydore on January 21.