Michael Phelps races great white shark (sort of) on Discovery Channel

The most successful Olympian of all time was no match for one of the world’s most feared animals when the two were pitched against each other to kick off the Discovery Channel’s Shark Week.

Michael Phelps swam a 100m stretch of warm Bahamas water in 38.1 seconds but lost out by two seconds to a great white shark swimming the same course.

The American swimmer is the world record holder for 100m and 200m butterfly as well as 400m individual medley.

He was even specially equipped with a wetsuit and monofin to mimic a shark’s movement through water.

But he could not compete with the species' 25mph average speed and its sheer size, with the animals reaching lengths of up to 6m.

He was more successful in a 50m practice run against a reef shark, which he completed in just 18.9 seconds.

The much hyped stunt aired on Sunday night as a premiere to Discovery Channel’s Shark Week.

The popular American TV channel has been hosting the programme since 1988 to draw in summer audiences and raise awareness about shark attacks and conservation.

Meanwhile Ryan Lochte, the second most decorated Olympic swimmer behind Michael Phelps, competed for viewers on National Geographic’s Shark Fest premiere.

Discovery Channel viewers were disappointed that Phelps was competing against a great white rather than a Mako, the fastest known shark.

It also became apparent, but only 57 minutes into the programme, that the race was actually a simulation and that Phelps was in fact competing against a computer-generated image of a shark based on a projection of its speed.

He completed the course in 38.1 seconds compared to the shark’s time of 36.1.

The program did include a real great white swimming in the 100-metre stretch behind a decoy of swimming seals.

Other highlights of the week will include a shark vs crocodile fight over sea turtles and a "great hammerhead invasion".

The programme has in the past attracted criticism for sensationalising the risk sharks pose to humans and for intentionally blurring the lines between drama and documentary.