Judi White rolls her eyes when asked about the appetite of her son, Connor.
''Incredibly huge,'' she says, gesturing to the constantly ''disappearing cupboard'' in the kitchen of their Blackheath home.
Connor's massive calorie intake is the result of the strapping 16-year-old's dedication to the sport of cycling.
A regular training ride for the St Columba's student is down into the Megalong Valley, back up to Blackheath, down into the Megalong again then back to Blackheath again - a journey of about 60 kilometres.
The Blue Mountains have no shortage of steep hills to test cyclists' stamina, but few can top the agonising climb out of the Megalong.
That kind of punishing regime, however, is what's required to be a top young rider.
Although Connor does much of his training on a road bike, his competitive passion is mountain biking.
In 2011 he came third in the Kanangra Classic 50km mountain bike event, which earned him a sponsorship from Wentworth Falls bike shop Bikeminded, then last year he went two better and won the race.
Now he has his sights set on winning an epic new Blue Mountains mountain biking event, Stinging Mettle, which will be run for the first time on April 6.
Sean Greenhill of Mountain Sports, the Wentworth Falls-based business behind Stinging Mettle, says the name of the race is perfectly apt - it will sting and it will test riders' mettle.
The main event is a 100km enduro from Glenbrook to Wentworth Falls and back to Glenbrook along some of the the most popular trails in Blue Mountains National Park - Andersons, The Oaks, Bennetts Ridge, Ironbark, Murphys and Ingar.
There is also a 50km race from Wentworth Falls to Glenbrook, with both rides finishing with a thrilling descent into Euroka Clearing.
Tristan Watz from Bikeminded, a sponsor of Stinging Mettle, said it represented a massive challenge for riders: ''It's not about winners, it's about just finishing. This race is really tough and will become a classic.''
Connor is expecting plenty of tough competition in Stinging Mettle because it will attract so many fellow mountain bikers.
''I think it's going to be a fantastic ride,'' he said. ''It's so close to Sydney for one and also the trails are great. They've been begging for this race. The Oaks is pretty much unbeatable. I can't wait. It should be huge, I reckon, and also great racing. Most [mountain bikers] I know are going in it.''
Go to www.mountainsports.com.au to find out more about Stinging Mettle or to enter the event.