The recruit at the Army Infantry School in Oudtshoorn has been admitted to a hospital intensive care unit.
The recruits were allegedly ordered to strip naked during a punitive physical training session, and beaten with broomsticks when they dropped poles.
This was claimed by Pikkie Greeff, South African National Defence Union spokesperson, who said there was now concern the recruit could lose his arm.
The recruits were being punished after they were found to have gone without permission to a pub last Thursday.
Most of the recruits were apparently sent to the base sick bay after the harrowing physical training session.
"We now know 11 recruits were caught out drinking and went awol," said Greeff. "They were given a punitive PT training session, which is outlawed in the defence force. Ten went to the sickbay and one went to a hospital intensive care unit."
A clampdown on information leaking out of the army base has now taken place, and the Mail & Guardian was informed that the military police were not given an easy time when trying to investigate the matter.
'Action will be taken'
A concerned medical doctor had apparently notified the military police after the recruits were brought into the sick bay.
South African National Defence Force (SANDF) spokesperson Brigadier General Xolani Mabanga said he had not yet been informed about the results of a board of inquiry, which he confirmed was taking place.
"Action will be taken against anyone who might have acted out of the rules, which governs the type of punishment befitting the violation," he said. "We are investigating whether they exceeded beyond what was required for the punishment."
Mabanga said he had heard allegations that the recruits had been forced to strip naked during the PT session, but he had no confirmation of this as yet.
"At this stage, we are just trying to gather together all the relevant information," he said.
Greeff said his union shopstewards were not allowed into the sick bay at the army base, and there were now guards surrounding it.
In August last year, a woman recruit committed suicide at the base. It was alleged at the time, her suicide note complained of humiliating treatment at the base. However, the results of an investigation by the SANDF investigation into the matter had never been revealed, said Greeff.