Former U.S. President George W. Bush famously averaged eight hours sleep each night while former Prime Minister Kevin Rudd survived on about three. Iron Lady Margaret Thatcher got by on four.
But when it comes to the election campaign, with Bill Shorten and Malcolm Turnbull travelling from electorate to electorate under the constant eye of the media and swinging voters, how crucial is getting enough sleep?
Former Foreign Minister Bob Carr, who spent more than a decade as NSW Premier, winning three election campaigns during his tenure, said a campaigning politician is often clocking off at 11pm and back on at 6am the following morning; so "the chief challenge" of an election is "not to be effected by fatigue".
In 1995, with two weeks left in the campaign, Carr remembers sitting in a studio preparing to film another set of ads and "being absolutely run down and exhausted". But he kept going and, upon reflection, credits his election win to those ads.
"But I also remember in the same campaign, snapping awake at 4am one morning, being very ill-tempered at a media conference and responding a bit too defensively to a reasonable question from a journalist," Carr told The Huffington Post Australia.
"I thought 'this is not going well' so I took the afternoon off, went home and got some sleep."
Getting enough sleep is crucial to maintaining cognitive function, said Integrative Sleep Specialist Dev Banerjee, with sleep deprivation reducing a person's attention span, memory and concentration -- all crucial for politicians campaigning in the public eye.
"At the end of the day, it's basically survival of the fittest, and whoever comes out the fittest, whoever comes out saying fewer gaffes, whoever comes out with their concentration, attention and cognition to engage with the electorates will fare best," Banerjee told HuffPost Australia.
"Obviously you need enough sleep for that."
Banerjee said politicians should be getting at least six hours of sleep per night (and napping when they can), but there are two other factors subtly weighing into the issue of sleep deprivation.
First, there's a sleep debt which can build up over time and during an eight-week election, politicians battle "non-stop sleep debt collection"; these are the one or two hours a politician misses on occasion which continuously build up to impact their cognitive ability.
The second factor can't be controlled by schedules or staffing, and is simply created by stress.
"You can be deprived, not only quantitatively of sleep, but you can be deprived of the quality of sleep as well," Banerjee said.
During campaigns, Carr would often find himself awake and alert at night; sometimes at midnight, other nights at 2am or even 4am. And if it was 4am, it was often easier just to stay awake.
"On one or two occasions it showed. On other occasions, I took a sleeping tablet when I snapped awake at midnight or 2am and ran the risk of being groggy or ill-tempered the next day," Carr said.
"The worst insomnia is when you know there's going to be something in the paper the next day. Something you feel defensive about, and you know you'll have to respond to.
"Instead of sleeping all you can do is run through your head what you'll say."
As Turnbull defends a majority, and a leadership validated by his party not the people, he is under more pressure, said Carr, while Shorten has already performed better than people expected.
You can be deprived not only quantitatively of sleep, but you can be deprived of the quality of sleep as well.
For both leaders, this internalised stress can be managed by the staff around a politician to a certain extent, which is crucial to the campaign said Carr. The key for staff is to handle problems before they get to the politician and avoid over-excitement over small developments throughout the campaign.
Staff should also manage a candidate's schedule to work in their favour, avoiding interviews -- especially with the most interrogative journalists -- after 8pm when they're most effected by a sleep deficit, said Banerjee; "There's a higher risk of tiredness leading to gaffes".
"And I think you need those personal aides to be with you to actually watch your behaviour," Banerjee said.
"At the first hint of grumpiness, tiredness that aide has to say 'Bill or Malcolm, you just need to have an hour or two break to get some rest'."
The issue came to the fore during the antics of the #SleeplessSenate in March when the chamber sat for a marathon 28 hours. Labor Senator Doug Cameron called upon the wise words of Monty Python during the stand-off over voting reform changes. And Independent Senator Nick Xenophon walked the parliamentary halls in pyjamas.
They were sleep-deprived decisions all candidates undoubtedly would prefer to avoid during the campaign.
And sleep makes up just part of an "interwoven fabric" maintaining health -- and consequently stamina -- during a campaign, with diet and exercise helping the resilience of a candidate, said Banerjee.
"You've got to maintain a cardio capacity, somehow that maintains your capacity in everything else," Carr said.
"Keeping your weight down, I think, is crucial because if you're struggling with excess kilos it must diminish your resilience."
While Turnbull has eschewed public displays of exercise, Shorten has taken a leaf out of the books of Julie Bishop and John Howard by embarking on a regular morning run. This daily routine, assisted by a healthy diet beginning with fruit and muesli, has helped the Labor leader drop more than 10 kilograms in the lead up to the election.
But the campaign is riddled with baked cakes, sausage sizzles and schooners. And sporadic opportunities to eat a nutritious meal.
"Your challenge in a campaign is that you go to functions and you might come home without getting anything proper to eat," Carr said.
"I think alcohol should be ruled out during the campaign, unless people have got into the habit of relaxing by a drink at night. But to be clear-headed is the most important thing, and you don't want to be struggling in the morning because it was an unfortunate choice of wine."
With more than five weeks to go in the longest election campaign in Australia's history, both leaders will be tested physically, with some voters starting to notice the Prime Minister tiring already.
"There's many people who are charming without any sleep.. but what you might find is the reaction time sometimes gets a bit slower," Banerjee said.
"And then there's a risk of being a bit cranky, there's a risk of losing patience, there's a risk of just general disengagement and tiredness."
While the candidate coming in second-best on July 2 may have an opportunity to address their sleep deficit following the election, the victor will need to jump straight into the governing the country. So when do they tackle eight-weeks of sleep debt?
"I think the joy of winning probably takes care of the fatigue," Carr said.
We think that statement would have bipartisan support.