But by the time he got back to Australia late in the year the signs of fatigue were obvious. It was 50km into the bike leg in November's Shepparton 70.3 Ironman in Victoria when he shut down, a recurring hip flexor injury the flashpoint signalling his season had run its course.
"With the amount of racing I'd done in the United States and in other parts of the world, when it came to doing the Aussie stuff back home late in the season it just didn't happen," Berkel said.
"I was cooked, mentally and physically wrecked, so I ended up shutting the year down early. But I've had a good break and I'm refreshed and raring to go in 2012."
Berkel's breakthrough win at Ironman Western Australia in 2008 made him the second youngest Ironman champion behind Thomas Hellriegal by 12 days, although he leapfrogged the German when he won his second Ironman distance event in Copenhagen in 2010, surpassing Hellriegal's accomplishment of two Ironman wins by three months.
Berkel backed up his Challenge Copenhagen win with another huge effort last August, although he had to work for it.
"In 2010 I won by five minutes, getting a nice lead off the bike which allowed me to cruise on the run and really enjoy it. Last year wasn't as easy." Berkel copped a four-minute penalty for drafting while braking into a corner. Attempts to dispute the punishment and continue racing were met with threats of disqualification.
"I'd moved into third before I was forced to stop, and then I watched fourth, then fifth, then sixth and eventually seventh run by me, each guy raising my level of frustration."
Berkel picked off the leaders until he had climbed to seventh at the 7km mark, easing back to 4min/km pace from his anger-fuelled 3:20min/km before a duel with Dane Jimmy Johnson over the final 8km saw the Aussie prevail by 30 seconds - "exciting but a bit too close for my liking."
Berkel rates last year's follow-up win in Denmark highly but it was his performance 12 months earlier that silenced the knockers who were looking at him as a one-hit wonder after Western Australia in 2008.
"I'd heard people whispering that I had gotten lucky at Busso... but I kept reminding myself that I'm young for an Ironman athlete. That sort of talk made winning again at Copenhagen an even sweeter victory, a bit of an 'up yours' to the non-believers."
It wasn't all podiums and victory parades in 2011 though, with Berkel DNF-ing at the rich Abu Dhabi International triathlon, where high winds and temperatures in the mid-30C meant only 16 of the 41 triathletes made it to the finish in the race for a share of US$250,000 prizemoney.
He was also eighth at the Ironman 70.3 World Championships near Las Vegas, making the rookie mistake of booking a hotel on the notorious strip.
"It probably wasn't the best idea and maybe we should have stayed out closer to the race [because] there were a few to many distractions and late nights leading up to the race.
"It's so easy to lose track of time in a city that never sleeps - next time I go over I'll know where not to stay."
Berkel had three week's complete rest after his Shepparton withdrawal, spending the past few weeks in the pool, swimming being the weakest of his three disciplines. He was third in the Port of Tauranga Half two years ago, storming home with the day's fastest run of 1h 14m 29s, to climb through the field after being seven minutes behind the leaders off the bike.
Berkel hopes to be nearer the pace tomorrow off the bike as he bids to become just the second Aussie after Craig Alexander in 2005 to triumph.
"I love this race and have nothing but good memories of my time here although I'm still not too happy with my performance in 2010 because I'd beaten all those guys before.
"I'm not 100 per cent fit, but sometimes when I've been 80 per cent in the past I've pulled out an awesome race so here's hoping."
Berkel's 2011 results
4th Revolution3 triathlon, South Carolina, US
3rd ESI Augusta Ironman 70.3, Georgia, US
8th Ironman world championship 70.3, Nevada, US
1st Challenge Copenhagen, Denmark, EU
2nd Racine Ironman 70.3, Wisconsin, US
3rd Challenge Cairns, Australia
1st Busselton Ironman 70.3, Western Australia
2nd Port Macquarie Ironman 70.3, Australia
1st Nissan BRW corporate triathlon (Team Daikin), Sydney
2nd Queensland Olympic distance championship