The Top Gun star, 61, turned heads after baring his six pack abs in a pair of blue swimming trunks as he waded into the water.

He also showed off his toned thighs and muscular derriere, which left many fans gushing about how good he looks for his age.

'Dude's like 60 and still crushing it, wild,' commented one.

Another wrote, 'He’s a couple of years older than me and I wish I looked that good.'

One fan wrote, 'Looks really good for his age. Respect anyone that keeps fit at that age like he does.'

While most of the comments were positive, some fans were critical of the Jerry Maguire actor's physique.

'Father Time catches up with all of us no matter how fast we think we’re moving,' one wrote cryptically.

'He may be in good nick for his age, but it’s what goes on in his head that concerns me!' joked one.

Another commented, 'You think that’s a ripped body? Oh yeah, for a guy - if that was a woman who had that type of body everybody would be making fun of her. #doublestandards.'

There isn't one secret to Tom's ultra fit lifestyle, after the star previously revealed he enjoys a wide-ranging list of physical activities to keep in shape.

He told Men's Health: 'Sea-kayaking, caving… fencing, treadmill, weights… rock climbing, hiking… I jog… I do so many different activities.'

Constantly challenging his body, the star follows a five day workout plan which included three days of weight training sessions and cardio as well as two days of more 'out-there' activities like fencing or hiking.