JEREZ, Spain (AP) Nico Rosberg is studying how he breathes as he looks to overhaul Formula One world champion and Mercedes teammate Lewis Hamilton.
Rosberg missed out on the title in dramatic fashion last year and wants to find improvements.
The German driver has tried perfecting new breathing techniques in order to find the ''one or two percent'' that could make all the difference this season.
Rosberg did better than Hamilton in qualifying last year, securing 11 pole positions compared to seven, but Hamilton dominated him - 11 wins to five - on race day.
That has been bugging Rosberg, who is determined to find the small margins that will work in his favor.
''I learned some things in the winter. For example, my breathing was something I could work on, my breathing in the race car,'' Rosberg explained. ''Because when we go through fast corners we hold the breath, because we have so much g-force. Of course I want to give you some insights, but not compromise my secrets.''
He's also stepped up his training regime.
''To be that little bit more fit at the end of races, a little bit more on it,'' the 29-year-old Rosberg said. ''That one or two percent that makes the difference in the end.''
Hamilton beat Rosberg by 67 points - but the margin was exaggerated by the double points on offer in the last race. Rosberg could have clinched the title, for example, if he had won and Hamilton placed third. But Hamilton won and Rosberg, blighted by technical problems, ended up 14th and out of the points.
He insists it did not take him long to get over it.
''Life went back to normal for me very quickly, one or two days,'' he said. ''I'm always motivated, but (this time) I have an extra little bit. To have this memory from last year. I know how awesome it feels to win races and how great it feels when I beat Lewis.''
Feelings were heightened last year due to the tension between the drivers. It led to several feuds, with Hamilton accusing his teammate of deliberately crashing into him at the Belgian GP in August.
Tensions were eased after Rosberg warmly congratulated Hamilton - his friend since their teenage years racking karts against each other - but Mercedes Head of Motorsport Toto Wolff does not rule out a repeat scenario.
''I have no illusions that 2015 will be an easier year,'' Wolff said. ''At this stage in their lives, they are teammates and competitors. This is how it is. It makes no sense to hope for harmony when no harmony can be expected.''
Mercedes could have defused the situation after the Spa incident by imposing team orders, but, despite the animosity it generated, let them continue racing against each other providing they did not create further controversy.
''That is when a team is getting pushed forward. The downside - the intense competition - we will live with,'' Wolff said. ''We have learned from last season. We have matured as a team, including the drivers.''