Bhutan's elderly devout Buddhists don't have to worry about a 30-minute-a-day exercise regime.
They clock up kilometres of exercise each day as they circumnavigate Bhutan's many temples.
After so many visits to this Himalayan kingdom I can now recognise familiar faces among the faithful.
Today there was the wiry old man with a wispy goatee beard, his hand gripping the wooden handle of a prayer wheel that he turned constantly.
Then there was the old woman, bent almost double, who passed by a temple entrance in Jakar, central Bhutan, her prayer beads sliding through her fingers. The sun had wrinkled her like a walnut but her eyes were as bright as they were last year.
While some pilgrims content themselves with walking around the temples, spinning their own prayer wheels, others spin the dozens of wheels that are often set into the outer walls of the temples themselves.
Some of these wheels are about 30cm high - others are heavy two-metre high giants.
If you're turning these, there's no need for any other upper body workout. Each spin improves one's karma and often a bell chimes musically with each rotation - what western gym can offer such extra incentives?
At the head of Bumthang's most populated valley, Jakar, sits one of the country's most revered temples - Khujey Lakhang.
Here the temple is set into the hillside itself so pilgrims cannot make circuits. Instead, once inside the temple they prostrate themselves on the blue pine timber floor.
Most of the planks in here are up to 50cms across. They've been treated with natural oils and have a satiny, red glow.
The altars are covered in the offerings of visitors - incense sticks, bottles of vegetable oils for the lamps, even packets of snack food. Once you have made your offering a monk on hand will pour holy water into your cupped hand from a brass long-spouted pot topped with peacock feathers.
I was the last to leave this temple today and as I did so the monk placed his feet on two long strips of carpet and began to skate gracefully across the floor - burnishing its shine before the next visitors.
Once, it was also traditional for the faithful to light butter lamps in the temple. However, the presence of so many naked flames in often tinder-dry wooden buildings - sometimes packed with visitors - monks in flowing robes and the added hazard of the odd earthquake created a major fire risk.
So now, many temples have special butter lamp pavilions set away from the main temple buildings.
It's not quite as atmospheric but even on a sunny day (and especially at night) the sight of hundreds of small flickering flames is impressive.
One of the more unusual additions to some of Bhutan's temples (especially given Buddhists' pacifist philosophy) is an AK47 propped up
by the statue of a god, or set in a glass cabinet.
They are there to remind the Bhutanese people to be thankful for the success of the Royal Bhutanese Army in removing insurgents from its southern border - a venture that was personally led by its fourth king.
It's an arresting sight but not perhaps nearly as much as some other architectural features here in Bhutan which I will tell you about soon.By Jill Worrall