As a former medal-winning trampolinist, Annalena Baerbock is used to aiming high. But the 40-year-old's next move may be her boldest yet, as she sets her sights on becoming Germany's first Green chancellor.

The opposition Greens on Monday tapped Baerbock to lead the left-leaning, ecologist party into the September 26 general elections.

With the party polling in second place, just behind Angela Merkel's conservatives, the Greens are poised to play a crucial role in the formation of the next government, even if they don't nab the top job.

The decision to go with Baerbock as chancellor candidate over fellow party leader Robert Habeck, a writer and philosopher seen as the more charismatic of the pair, might once have come as a surprise.

But the mum-of-two and trained lawyer has stepped out of Habeck's shadow in recent months, savvily using the media spotlight on the pandemic to criticise the government for not prioritising children during the crisis, while laying out her own proposals.

Observers often describe Baerbock as smart and determined, with a meticulous attention to policy details. 

"She keeps asking questions until she has really understood an issue," a party source told the Handelsblatt daily. "She won't be fobbed off."

Critics point out that Baerbock has never held a government role, raising doubts about her stamina for the election battle and the likely coalition haggling afterwards.

"Three years as party leader, being a lawmaker and mother of young children tend to toughen you up," Baerbock has countered.

Taught to 'be brave

Raised on a farm near the northern city of Hanover, Baerbock got an early taste of politics when her parents took her to anti-nuclear demonstrations in the 1980s, a movement that spurred the creation of the Green party.

As a teenager Baerbock took part in trampoline competitions, winning three bronze medals in German championships. The sport taught her to "be brave", she has said.

Baerbock studied political science and public law in Hanover before getting a master's degree in public international law from the London School of Economics.

After trying her hand at journalism, Baerbock joined the Greens in 2005 and rose to become head of the party's Brandenburg branch in 2009.

She entered the Bundestag lower house of parliament as a lawmaker in 2013.

Along the way she met her husband Daniel Holefleisch, a public affairs manager at Deutsche Post. They have two daughters and live in Potsdam near Berlin.

Head and heart

As the Greens' co-leaders since 2018, Baerbock and Habeck have been credited with completing the party's transformation from its hippy, peace activist roots to a mainstream force to be reckoned with.

Growing concerns about climate change and disenchantment with the political establishment have fuelled support for the Greens among urban voters, middleclass families and "Fridays for Future" youths.

On a regional level, the Greens are now part of government coalitions in more than half of Germany's 16 states.

In the 2019 European Parliament elections, the Greens soared to 20.5 percent of the vote in Germany while Merkel's CDU/CSU bloc and their centre-left SPD coalition partners suffered losses.

The Greens rewarded Baerbock and Habeck by re-electing the leadership duo, Baerbock with a record score of 97 percent.

In a break with tradition, both Baerbock and Habeck represent the "Realo" wing of the Green party, seen as more pragmatic and centrist than the radical "Fundi" camp.

Should the Greens come to power, Baerbock says they would bring forward Germany's coal exit to 2030, the same year they want to ban the sale of new fossil fuel cars.

Baerbock favours greater European responsibility in security and defence matters, and has been critical of the Nord Stream 2 gas pipeline project with Russia that has Merkel's backing but irked allies.

Having first-hand experience of juggling homeschooling with working from home during the pandemic, Baerbock has called for more support for families and teachers.

She has not ruled out governing in tandem with the CDU-CSU should they remain Germany's biggest bloc after Merkel bows out, but she describes the conservatives as representing the past.

Germany's next chancellor, she told the RND newspaper group, "should have both feet in the real world" and "do politics not just with the head, but also the heart".