Steele said power athletes like Ms Ostapchuk would be more likely to use testosterone or growth hormones which are difficult to detect in drug tests.
He said it was odd that Ostapchuk, who is accusing Olympic organisers of prejudice against Belarussian athletes, did not test positive in any of her prior 16 tests she claims to have undergone since April.
"If she's using it, then you would have expected her to have been using it for some months, and therefore you would expect it to have been picked up in those prior tests."
"You would expect to find it during a training phase, and not during a competition phase.
It almost certainly would make no difference taking the steroid the week before the games, and even if you did it most certainly wouldn't be worth the risk, he said.
For sports like shot put, Steele said if athletes were to take performance enhancing drugs, they would do it about two to three months prior to the event to make the most of their training.
During this period we target athletes like Valerie Adams, said Steele.
"We want our athletes to be drug free and so we have a vigorous testing process, as is the case with Val."
Ostapchuk called the positive doping results that saw her stripped of an Olympic gold medal "nonsense" and said they "can't be possible".
The gold medal for Olympic women's shot put was given to Kiwi Valerie Adams after Ostapchuk tested positive twice for the banned steroid metenolone. Evgeniia Kolodko of Russia was upgraded to silver and fourth-place finisher Gong Lijiao of China moved up to bronze.
Adams finished second behind Ostapchuk, her throw of 20.7m well behind the Belarusian's 21.36m.
After being stripped of her medal, Ostapchuk told Belarus media she had done nothing wrong.
"I do not understand where it could come from," Ostapchuk told internet news agency Noviny.by.
"I'm looking like an idiot to take this in heading for the games and knowing that it is so easy to be tested. Nonsense. I'm being tested every month, every week.
"I hope for the better. The most important for me is to clear my reputation.
"I've been in the sport for so many years and have never faced any claims. And now at the major event and after the gold medal ... I do not understand it."
She elaborated on her comments while talking to local media in Minsk.
"I was tested twice more in London but I don't have any idea how this thing ended up in my body. I'm going to fight this allegation because it can't be possible," she said.
"In total, I've been tested 16 times since April. You must be a complete idiot to take doping just before the competition especially such an outdated drug as a steroid, knowing you're going to be tested not once but probably several times."
Ostapchuk also accused Olympic organisers of prejudice against the Belarussian athletes, Reuters reported.
"You all know how we had been treated there, just ask Ivan Tsikhan," she said, referring to the Belarussian hammer thrower booted out of this year's Olympics because of a positive drug test from the 2004 Games in Athens.
"We must fight for our rights. If we remain silent and accept the punishment, then they will continue to humiliate us."
The 31-year-old, world champion in 2005, recorded the biggest shotput mark in a decade in the lead up to the Olympics. She won the gold with a mark of 21.36 metres.
The IOC said she tested positive for the steroid metenolone on August 5, a day before her competition, and immediately after she won the event.
The "A'' and the backup "B'' samples from both tests came back positive.
A hearing was held a few hours before the closing ceremony, attended by three Belarus team officials. They told the IOC that Ostapchuk had been tested in Belarus on July 25, July 26 and August 1, and the results were negative.
The athlete arrived in London on August 4 and went straight to the athletes village.
"They had no explanation as to why such a substance would have been found in the sample of the athlete," the IOC said.
After seeing the test results, the Belarus team did not contest that the steroids were found in her system.
She was formally expelled from the games and had her victory and medal removed from the records. She was the eighth athlete, and first medalist, caught during the IOC's London drug-testing program.
"Catching cheats like this sends a message to all those who dope that we will catch them," IOC spokesman Mark Adams said.
Track and field's governing body, the IAAF, will consider further action against Ostapchuk, who could face a two-year ban from the sport.
Belarusian deputy Sports and Tourism Minister Cheslav Shulga told state media BeITA that Ostapchuk was tested on July 30 and came out clean.
"Some mistake or misunderstanding may have happened. We still recognise Nadzeya Ostapchuk as our Olympic champion," he said.
"Let's wait for the official decision of the International Olympic Committee. The Belarusian side will not take an action for now."
Shulga refused to link the event to the disqualification of Ostapchuk's compatriot Tikhon.
"The decision on Tikhon was unethical and wrong. I refuse to believe that the Olympic movement has political connections. But facts state otherwise," he said.
Adams said Ostapchuk's career was "history".
"My feeling is I don't want to waste any energy on her. I just want to enjoy the moment."
Adams' gold medal lifts New Zealand one place on the medal table to 15th, ahead of Cuba.
The six gold medals won at London is New Zealand's second best gold haul, just behind the eight of Los Angeles in 1984.
New Zealand's total medal haul of 13 equals the country's best ever, achieved at the Seoul games of 1988.
- APNZ with AP
