The army recruit who collapsed during a gruelling SAS training exercise is now in a critical condition in Auckland Hospital after his health deteriorated yesterday afternoon.

Lieutenant Alexander Teira Cowan, 25, collapsed while running in the Hunua Ranges near the SAS base in South Auckland on Wednesday last week.

He was considered to be in a critical but stable condition earlier this week.

A hospital spokeswoman said his health had worsened yesterday afternoon and he was now in a critical condition.


Mr Cowan fell ill during an exercise where he and other recruits were required to complete an 8km run in uniform while carrying equipment in a load-carrying vest weighing about 10kg.

The group were reaching the end of the activity when he stopped and fell to the ground and became unconscious.

He received immediate first aid assistance and an army medic started treatment within five minutes of his collapse.

The incident has sparked an inquiry into selection processes for the NZSAS.

Defence Force spokesman Major John Gordon said there was a robust medical plan in place for the training.

"When you have such rigorous and demanding selection processes there is going to be a risk of injury or medical issues," he said.

"The large proportion of issues would relate to physical injury as opposed to any sort of heat-related issues."

Army chief Major-General Tim Keating said the inquiry would review whether the selection process needed to change.