Making it as a Premier League footballer is incredibly tricky, and the league's medical advisor has lifted the lid on what is required for players to stay at the top level.
The Premier League is viewed across the world as being one of the best quality divisions in world football.
A large number of the world's best players operate in England and the demands on stars include strict rules on their sleep and their nutrition.
Dr Mark Gillett, 53, who became the league's medical advisor in 2018, told the Telegraph how the athleticism of Premier League stars is now 'light years' away from what it was, due to advancements in science.
As he outlined the physical demands on players, he referenced a line from a respected peer that players 'consists of their last 100 meals'.
'Recovery after a game is key. Refuel as soon as possible,' he explains.
'Food in the dressing room, individualised drinks. Some form of protein wrap – chicken or vegan. Fluids with electrolytes.
'Sometimes they might need a pizza. Especially as they are often on a really strict diet for weeks on end. But there has been a big move towards whole foods rather than supplements.'
He goes on to add that players have a full meal when they are back on the bus - with sushi, or 'high quality' meat, with some pasta, an alternative option.
But nutrition is just one part of a much wider analysis on player health, fitness and performance.
Gillett is huge on the importance of what he terms 'sleep hygiene' - with some clubs even having specially designed mattresses installed in player homes to familiarise them ahead of overnight away trips.
He explains that reducing screen time on phones and laptops in the hour before sleep is crucial, while 'blue lights' are important for players.
Gillett adds: 'We go through it individually. There are sleep experts who work with each player.
'You don't want to be led by what a tracking device tells you as players start worrying about it. It's more about intuition and common sense.'
Ice baths, a gruelling post-game ritual, is one area where Gillett does not want to see players cut corners.
They are done to repair muscles quickly and Gillett advises players to wear 'compression tights' in the ice water.
Given the quality on show each week in the Premier League, it is a bold final statement from Gillett that the division is 'nowhere near reaching the ceiling' in terms of how fit players can be.