A technical overhaul has rower Robbie Manson planning to dominate the single sculling world this year

He's finished fifth at the last two world championships after triumphing at World Cup regattas earlier in the season.

Manson still holds the world's best time in the boat, and is favourite to defend his national title on Saturday at Lake Ruataniwha.

He says he made the adjustments before a successful Christmas regatta.

Manson says he feels like he's been able to hold the changes, so is looking forward to seeing how he stacks up later in the year.