"Murray Stevenson is an exercising and training guru and the new coach (Bob) Woolmer regards him as the best in the business," Pakistan Cricket Board (PCB) chief executive Ramiz Raja said.
Pakistan last week replaced Javed Miandad with Woolmer, who coached South Africa between 1994 to 1999, and has also hired former Australian Greg Chappell and Barry Richards as batting consultants.
Raja said the hiring of Stevenson would help control injuries to team players at international level.
Like Woolmer, the 28-year-old Stevenson will also be part of Pakistan team management until the 2007 World Cup.
Pakistan had suffered excessive injury problems to key players since their tour of New Zealand in 2001 and their last home series earlier this year against India.
Fast bowlers Shoaib Akhtar, Shabbir Ahmed, Umar Gul and wicketkeeper Moin Khan missed crucial games because of injuries.
"Stevenson will rehabilitate the injured player through a fitness regime process and we need such an expert for a long time," said Raja.
Raja said Pakistan has also advertised a position of physiotherapist to treat injuries.