Under the care of Les Theodore, won one of his four starts as two-year-old, a maiden at Bendigo on 28 April 1988. At three, he was transferred to the Sydney stables of Bart Cummings, where he won four races and was runner-up in the Canterbury Guineas. At season's end, his record stood at a relatively unprepossessing five wins from 16 starts, although Les Theodore claims to have told the staff at Lindsay Park that the horse was a 'champion'. Now trained by Colin Hayes, Better Loosen Up resumed late in the spring of 1989, on Caulfield Cup day, with a close second, and finished the year with three Group One wins in as many starts, in the Honda Stakes, the Winfield Stakes, and the Railway Stakes. In the new year, he defeated Super Impose and Vo Rogue in the Blamey and the Segenhoe Stakes, and was runner-up to Vo Rogue in the Australian Cup in between. In his final starts for the season, he was defeated by Sydeston on heavy tracks in the Mercedes Classic and Queen Elizabeth Stakes. At five, under the care of David Hayes, Better Loosen Up was better again. After a first-up defeat in the Liston Stakes, he was undefeated for the rest of the season, and, in successive races, took out the Feehan Stakes, the Turnbull Stakes, the Cox Plate, the Mackinnon Stakes, the Japan Cup, and, in the new year, the Blamey Stakes and the Australian Cup. In the Cox Plate, Better Loosen Up had come from an estimated 30 lengths off the lead to win in course-record time; in the Mackinnon Stakes, on Derby Day, he was one of a 'world record' six Group winners for his trainer; in the Japan Cup, he scored a thrilling win to racecaller Bryan Martin's cry of 'Better Loosen Up has won for Australia', and remains the only Australian horse to do so; in the Australian Cup, he defeated Vo Rogue by lengths. Following this season, Better Loosen Up was named Australia's champion racehorse in 1991. A leg injury, which had cut short his autumn campaign, restricted him to just 12 further starts, at six and seven, and he failed to reach the same heights. His best performance came in the Cox Plate of 1992, where he was beaten just over a length by Super Impose, and successfully protested against Let's Elope, who was second past-the-post. He was retired in February 1993, within days of Super Impose, with which he would star on 'Super Better Best' – the story of how two geldings rose from obscurity to amass a '$10 million fortune'.
