Footballers usually slow down at 32. Years of wear and tear take their toll and their bodies begin to fail.
The reactions are less sharp, the movement less regular. The body can't perform what the mind tells it to. They may anticipate the next move, but fail to make the run.
How footballers deal with this change in physicality is as hard as the growing pains that come when a teenager develops into an adult.
This season, Jamie Vardy has bucked the trend. He isn't merely dealing with his advancing years, he's thriving in them.
But it was only 10 months ago that the former England international was far from happy with life at Leicester, and particularly his relationship with former manager Claude Puel.
Vardy was dropped for a 3-1 defeat at Tottenham in February, and only a few months earlier he had voiced his displeasure at the the Frenchman's style of play, unsuited to his own.
'Does it [suit me]? No, but is that down to me to adapt to it? Yes. And, obviously, the only way I'm going to do that and keep progressing is working hard on the training field.
'It does get a bit frustrating, but we are transitioning into a different style of play. I think we've just got to keep working hard on it and eventually it will get us going forward that bit quicker.
Puel didn't last much longer, paying the price for both poor results and a distinct lack of style. Leicester's owners saw an opportunity and coaxed Brendan Rodgers into leaving Celtic three months early.
And since Rodgers arrived in late February, he hasn't looked back. Vardy hasn't just rediscovered his mojo, he's been reinvented and is now surpassing the level he reached when his goals spearheaded Leicester's Premier League miracle in 2016.
He has scored 20 goals in 22 games since Rodgers' first fixture in charge - a 2-1 defeat at Watford on March 3 - more than any other player in the division.
The 10 games Rodgers had at the end of last season have seen Leicester fly out of the traps this campaign, and they duly sit joint second in the table alongside Chelsea, but eight points adrift of leaders Liverpool.
James Maddison and Youri Tielemans have excelled, while Caglar Soyuncu has proved a revelation alongside Jonny Evans at the heart of defence. But simply, Leicester would not be where they are without Vardy.
He has contributed directly, via a goal or assist, to 38 per cent of Leicester's goals this season, a bigger percentage than any other player in the league. Tammy Abraham is behind him on 37, with Sergio Aguero a long way down in third on 26.
It's Vardy's numbers that really stand up compared to his peers. Having scored 11 times from just 25 shots, his shot conversion rate of 44 per cent dwarfs that of his peers Pierre-Emerick Aubameyang, Sadio Mane, Tammy Abraham, Harry Kane and Sergio Aguero.
Vardy has taken fewer shots than any of them, and is averaging only 20.9 touches per 90 minutes this season, way down on the 32.5 he averaged in 2015-16.
He is less involved, and yet his return of 0.92 goals per 90 minutes is easily his best return in the Premier League. When he fired in 24 goals to lead the Foxes to the title three years ago he was going at 0.69 per 90.
Rodgers says he has developed a 'strong relationship' with Vardy since taking charge. It shows on the pitch. He has stripped away elements of the veteran striker's game.
He still possesses the same roadrunner pace that so frightened defences in 2016. But now he uses it sparingly and to better effect. It keeps him fresher in games, something which has also been helped by his lack of international football since retiring from England duty after the World Cup last year.
You don't see him chase down so many lost causes, or press from the front with the same vigour. The desire to get in behind opposition defences remains, but the bulk of his game has become much smarter and about picking those moments.
He showed his electric pace to get in behind the Sheffield United defence and thump a left-footed strike home in August. Then against Bournemouth he raced onto a ball over the top before unleashing an impudent lob over a stranded Aaron Ramsdale.
His two most recent goals against Crystal Palace and Arsenal showcased his game intelligence. In both cases he checked his run, found space in a packed penalty area and backed his undoubted finishing ability.
He's also profited from outstanding delivery. Marc Albrighton, Harvey Barnes and Ben Chilwell have all provided him with three close-range headers. He has the movement and awareness to be in the best possible place, but it makes his life easier not having to do it all on his own.
All these elements with Vardy at the fore have helped transform Leicester into a Champions League force, exploiting the disarray among the established elite.
It's all come against the backdrop of a public spat that thrust Vardy onto the front pages. Wife Rebekah was involved in a social media feud with Coleen Rooney last month after being publicly accused of leaking private stories about the Rooney family to the press.
The story became a national talking point, even leading news bulletins, reflecting the public's interest in this very modern social media storm, and Rebekah was quick to deny any involvement in leaking information about the Rooneys.
Vardy, typically, took it in his stride. When Burnley fans chanted 'Jamie Vardy, your wife is a grass', he responded in the only way he knows how. By scoring. And reminding them of the fact, pinning his ears back to silence the boo boys in celebration.
Vardy's made a career out of proving a point and proving people wrong. At the age of 32 he's proving yet another one.
