"If you put in things like alcohol and cigarettes it starts to rust the bucket and you never get it full, no matter what.
"That's what it's all about, filling the bucket with good things. If you look after it, you get a pretty full bucket.''
Mr Salek has lived by that metaphor for years, which has no doubt contributed to his extreme fitness for his age. Mr Salek brushed off a recent swim from Motiti Island to the mainland as "only 10km''.
Tomorrow Mr Salek will complete the swim leg while Mr Stewart does the running.
Mr Salek's daughter Anna will fill the cycling spot of original Old Fart Don Robinson, 78, who has been unable to train this year.
At 74, Mr Stewart is a few years younger but shares Mr Salek's enthusiasm for "getting out there and enjoying life''.
"You get a lot of satisfaction having completed it. You tend to want it to be over when you are three-quarters of the way through but there's nothing better than finishing a run, having a shower and putting on some clean clothes afterwards. It's the best feeling.''
Mr Salek said the Old Farts have had incredible support from the local sporting community, some of whom arranged free registration for the team because of their efforts.
"They think we are special. We don't. We just enjoy it. It's all the textbook stuff they say about endorphins.
"I wake up in the morning and I feel 90 but the moment when I do a few laps of the pool I feel 50.''