Paralympic 400m star Oscar Pistorius has failed in his bid to compete at this year's Olympic Games in Beijing.
Pistorius had his legs amputated when he was a child
The IAAF, athletics' governing body, ruled his prosthetic limbs give him an advantage over able-bodied opponents and contravene rules on technical aids.
A scientific study revealed that Pistorius, nicknamed "Blade Runner", used 25% less energy than able-bodied runners to run at the same speed.
The 21-year-old South African said last week he would appeal against any ban.
"I feel that it is my responsibility, on behalf of other disabled athletes, to stand firm," he said. "I will appeal [against] this decision at the highest levels, while also continuing with my quest to race in the Paralympic Games and hopefully the Olympic Games."
The onus is now on us to prove that he is not getting an advantage
His agent Peet van Zyl told BBC Sport that he and Pistorius would sit down with their legal team to decide how to take their case forward.
"We are obviously very disappointed," Van Zyl said. "We were really hoping that he would be allowed (to compete).
"The natural feeling from our side is to appeal the verdict. The onus is now on us to prove that he is not getting an advantage."
It is likely that Pistorius will lodge an appeal to the Court of Arbitration for Sport (CAS).
Pistorius, who holds the Paralympic world record of 46.34 seconds, spent two days in Cologne last November undergoing tests alongside five able-bodied athletes of similar ability.
Professor Peter Bruggemann's research concluded an athlete using the "Cheetah prosthetic" could run at the same speed as able-bodied athletes but use less energy.
The tests also revealed that running with prosthetic blades led to less vertical motion combined with 30% less mechanical work for lifting the body.
Based on this and other test results, it was decided the blades should be considered as technical aids in clear contravention of IAAF rules.
Last year, the IAAF banned the use of any device incorporating springs, wheels "or any other element that provides the user with an advantage over another athlete not using such a device".
The IAAF's decision means that Pistorius will not be allowed to run in any competitions involving able-bodied athletes.
Last summer he finished second in a 'B' race in 46.90 seconds at the Rome Golden League in July and, two days later, was disqualified for running out of his lane in Sheffield.
Pistorius was 11 months old when his legs were amputated below the knee but only began running competitively on the carbon fibre blades four years ago.
He had immediate success winning the 200m at the Athens Paralympic Games and bronze in the 100m.
The South African also holds Paralympic world records for the 200m (21.58secs) and 100m (10.91secs).
He has come close to times set by able-bodied athletes but has yet to attain the Olympic qualifying time over 400m.
Pistorius's Paralympic world record of 46.34 seconds is also some way off the best able-bodies athletes.
The fastest active athlete is American Jeremy Wariner, whose best time is 43.50secs, while fellow countryman Michael Johnson holds the world record at 43.18.
At last year's BBC Sports Personality of the Year awards, Pistorius won the Helen Rollason Award, given annually to an athlete showing courage in the face of adversity.