But now, as recent images of ultra-fit celebrities like Sean Penn, Paula Hamilton and Melanie Griffith reveal, it would appear that the over-fifties are proving they can still look fabulous - and flaunt it.
Model Paula Hamilton, 51, who entered the Celebrity Big Brother house last night, showed just what it takes to retain her youthful figure as photographs emerged of the star practising some very impressive yoga moves poolside - wearing a tiny pink bikini.
Fit in their fifties: Paula Hamilton, left, and Melanie Griffith show off their toned and trim bodies
The exercise enthusiast, who made her name in the 1980s in an advertising campaign for the VW Golf, has such a passion for yoga that she even released her own DVD, The Y Plan, to teach those at home how to get a supermodel body.
Supple: Paula Hamilton practices yoga to stay in shape at her age
Speaking to US Weekly, Mrs Antonio Banderas said: 'I don't know if I look that great.
'[But] I work out a lot. I have a trainer that I [work with] four times a week, and I do hot yoga.'
Like both Paula and Melanie, Julianne Moore appears to have defied the ageing process.
The 52-year-old star cut a trim shape as she enjoyed a dip in the sea on a holiday in Hawaii with her family.
Julianne showed off a slim shape in a black halter neck bikini top by Melissa Odabash and a pair of shorts.
And as for Sharon Stone, who rose to fame showing off her immaculate body in iconic movie Basic Instinct in the 1990s.
Even in her mid-fifties, she is still flaunting her figure and proves that her GI (Glycaemic Index) diet and Pilates classes are serving their purpose.
Gym bunny: Melanie Griffith can often be spotted leaving her yoga or training sessions
Looking good: Julianne Moore cut a trim shape in her swimwear while Sharon Stone proved that her healthy regime pays off
The two-time Oscar winner looked like he was in the best shape of his life as he strolled on the sand in nothing but blue snowflake-patterned swim trunks.
The Milk star - sporting shoulder-length hair and a moustache - used the picturesque Hawaiian getaway to flaunt his sinewy arms with bulging veins, six-pack abs, and defined pecs.
It is clear to see why the single stud has romanced numerous beauties over the years, including models Brigitte Nielsen, Petra Nemcova, Jessica White, and actress Scarlett Johansson.
Flying the flag for the 50-plus men: Sean Penn showed off his six-pack on the beach yesterday
The 50-year-old New Jersey native showed off his shirtless physique while his wife avoided the tan lines in a slimming brown one-piece during their vacation in St Barts.
Being the blue-collar workhorse that he is, the lead singer of the phenomenally successful Bon Jovi doesn't try and make out that his youthfulness is down to anything but good, hard graft.
And that pertains to keeping fit as the frontman was spotted sticking to his gruelling running regime (up very steep heels) on the leisure mecca that is the island of St Barts.
Trim: Bon Jovi showed off his athletic physique in St Barts this week and proves he achieves it with hard graft