Eager to prove that 1) she does have a sense of humour underneath that homely exterior and 2) she really did ‘consciously uncouple’ from Chris Martin on the best possible terms and isn’t fussed by those Jennifer Lawrence rumours, Gwyneth Paltrow took on the ALS ice bucket challenge.

The actress - who was challenged by Martha Stewart, per personal trainer Tracy Anderson and chef Jose Andres - chose to do so in her back garden, in a skimpy black bikini.

She also chose to omit the ice part of the challenge. Which is kind of the point of the whole thing.

"Hi, I'm going to alsa.org to donate money for ALS but in the meantime I’ll do this and nominate Chris Martin, Cameron Diaz and Stella McCartney," the 41-year-old tells her Instagram followers, before letting out an ear-piercing squeal and skipping off stage left.

The campaign craze sweeping the A-list nation has seen all manner of household names take up the challenge, including former US President George W. Bush, Microsoft founder Bill Gates, Facebook's Mark Zuckerberg and even steely US Vogue editor Anna Wintour.

But there is a reason behind the madness. The challenge raises money and awareness for amyotrophic lateral sclerosis (ALS) or Lou Gehrig's disease.

Amyotrophic lateral sclerosis affects the brain and the spinal cord. Motor neurons degenerate and die which makes it increasingly difficult for sufferers to move their muscles.

When their muscles aren’t used enough, they stop working entirely and patients with ALS begin to feel weak, have difficulty speaking, swallowing and breathing. In the later stages of the illness, patients may become totally paralyzed.

Those involved the ice bucket challenge can either choose to have a bucket of ice and water dumped over their heads within 24 hours of them being nominated, as well as donating $10, or write out a cheque of $100 to an ALS charity of choice.