Follis made her international debut in February 1995 as part of the Cross-Country Continental Cup in Brusson . On December 13th of the same year she made her first start in the cross-country skiing world cup in the same place , but finished in 54th place, far behind the world's best. On February 2, 1997 she managed to finish third in Walchsee for the first time on a podium place in the Continental Cup. A few days later started Follis at the Junior World Championships in Canada Canmore . After a poor 25th place over the 5 km in the classic style, she finished eighth in the 15 km freestyle race. With the relay she won the gold medal there. In December 1997, at the World Cup in Val di Fiemme on the trails in Lago di Tesero, with placements beyond the top 70, she again missed the leap into the top of the world. As a result, Follis remained in the roster for the Continental Cup and subsequently only rarely made World Cup appearances.
In February 2000, Follis came 21st at the Transjurassienne for the first time in the World Cup points. She also succeeded in doing this at the start of the 2000/01 season in Santa Caterina Valfurva in March. In the sprint in Nové Město na Moravě , she achieved her best World Cup result in seventh place. The following Nordic World Ski Championships 2001 in Finland's Lahti Follis was ranked 28 in the 10-km pursuit. In the sprint, she finished 13th. On December 16, 2001, Follis made it onto the podium for the first time in the relay race together with Cristina Paluselli , Gabriella Paruzzi and Stefania Belmondo . She repeated this season success in November of the following year in Kiruna, Sweden . In February 2003 she also reached third place in the team sprint with Karin Moroder . Almost a week later she started at the World Championships in Val di Fiemme. In doing so, she missed the top 20 in both individual disciplines and did not get past seventh in the relay.
With the 2003/04 World Cup season , Follis was able to further improve its performance. On January 18, 2004, in Nové Město na Moravě, she just barely missed her first individual podium in the World Cup in fourth. In the team sprint in Oberstdorf she just missed the top three with Sabina Valbusa . In October she competed in the team sprint with Gabriella Paruzzi for the first time in Düsseldorf and came in third. In the Swiss Bern , the duo repeated the success. At the Nordic World Ski Championships in Oberstdorf in 2005 , Follis came in 18th in the individual over 10 km freestyle. In the relay race she won the bronze medal together with Antonella Confortola as well as Paruzzi and Valbusa behind the relays from Norway and Russia but ahead of the defending champions from Germany.
After Follis qualified for the 2006 Winter Olympics in Turin at the beginning of 2006 , after the relay medal in 2005, she and her teammates again belonged to the medal favorites. This was confirmed by the team and secured the bronze medal. In the sprint and team sprint she finished seventh, over 30 km she was twelfth and in the skiathlon she was 36th. At the first World Cup after the games in Borlänge , Follis celebrated her first World Cup victory in the sprint. In Changchun , China , she won the qualification, but in the end did not get past ninth place in the race. In the World Cup season 2006/07 started Follis well and was the second World Cup in La Clusaz in third on the podium again. She finished second in the Munich sprint and was the first to reach the podium in a stage of the Tour de Ski . After she reached the podium again as third in Asiago, she finished the Tour de Ski 2006/07 as 16th in the overall standings a little later . Two weeks later she won her second World Cup with the sprint in Rybinsk .
At the 2007 World Championships in Sapporo , Japan , Follis won bronze over 10 km freestyle . In the Tour de Ski 2007/08 she won a stage for the first time in Prague . After she reached the top 10 in all other stages except one, she finished the tour in third place overall. On June 27, 2008 Follis started the Rollerski World Cup for the first time and won the Piglio 5 km race . But for the time being it was her only international start in the summer. In January 2009, she and Magda Genuin won the Olympic dress rehearsal in the team sprint in Whistler. In Rybinsk, she achieved two second places. At the 2009 World Championships in Liberec , Czech Republic , Follis secured the sprint title. In the team sprint she started for the first time with Marianna Longa and won bronze. After she was only fifth with the relay, she finished the World Championships with an eighth place over the 30 km.
At the 2010 Winter Olympics in Vancouver , the now 32-year-old Follis achieved two fourth places in the team sprint and with the relay. She was eleventh in the 10 km individual race and ninth in the skiathlon. In November 2010 she was ninth in the overall ranking of the Nordic Opening in Kuusamo . A little later, Follis won the sprint in Düsseldorf before she also triumphed in the team sprint with Magda Genuin. The Tour de Ski 2010/11 she finished in fourth place after two second places in the stages in Dobbiaco reached. In February she won her first relay world cup together with Magda Genuin, Marianna Longa and Silvia Rupil . Two weeks later she started at the Nordic World Ski Championships in Oslo , where she won the silver medal in the sprint.
Her last World Cup season 2010/11 ended Follis as the best season of her career in third place overall. She also secured third place in the Sprint World Cup, for the second time after 2009. Before that, she had won another stage in her last World Cup start in Falun and was only 2.9 seconds behind Therese Johaug in the 2011 cross-country World Cup final fourth place.
After the end of her active career, Follis withdrew completely from the sport and opened a pizzeria together with her husband under the name Oro Argento Bronzo ( German gold silver bronze ) in Gressoney-Saint-Jean .