Great Britain is likely to be one of the biggest winners in this year's Olympics, boasting an impressive rise from their performance at the Beijing games.
Team GB is predicted to win 56 medals, compared with 47 in Beijing four years ago.
Britain is expected to rank fourth behind the US, China and Russia.
Russia and Australia were forecast to have the most disappointing results. Despite taking third place in the medal rankings, Russia's predicted total of 62 medals was 11 less than the country won in 2008.
Australia was expected to reduce its medal tally from 46 to 36.
At the top of the table, the US was forecast to collect 112 medals compared with 110 four years ago.
The forecast, made by an international team of researchers, is based on a range of factors including a country's economic system, Gross Domestic Product, numbers of medals won previously, and public spending on sport.
Hosting, or having hosted, the Games is another key factor that is said to influence medal fortunes.
Brazil would provide the biggest surprise by winning 29 medals, almost double what it gained in 2008, according to the study. But there were also high hopes for Britain.
"The first case is due mainly to economic growth, while Great Britain will take advantage of being the next organiser, which is always an important stimulant," said economist Professor David Forrest, from the University of Salford, who led the research.
Prof Forrest and a team of Spanish colleagues carried out the research for the Madrid Sportometrics Study Group.
Writing on the University of Salford's website, he explained how the predictive model worked.
"GDP per head of population and population size remain the most obvious guide to Olympic medal performance, but there are other variables which can significantly affect a country's medal-winning potential," he wrote.
"These include previous Olympic team medal achievement, the over-performance of communist and former communist countries compared to what would be expected given their resources, and the 'host effect', with the home national team expected to win more medals than usual."
Countries due to host the Olympics had been shown to increase their medal success, even at the Games preceding the one they were organising, said Prof Forrest.
Along with economic growth, this was likely to propel Brazil's competitiveness in London.
"Before Beijing we also identified that countries who are due to host the next Olympics tend to win more medals at the Games immediately before their own," he wrote. "Great Britain, for example, went from 30 medals at Athens to 47 at Beijing, suggesting that investment in Olympic sports well ahead of hosting a Games has a marked impact in a relatively short space of time.
"In line with this, we're predicting that at London 2012 the Brazilian team will win nearly double the number of medals they achieved in 2008 - up from 15 to 29. In contrast, we believe that Australia's post-Sydney Olympics decline will continue, as we estimate they will win 38 medals in London compared to 46 in Beijing."
Spending on sport was a "very powerful predictor" of medal winning, he added.