The 23-year-old, a quadruple silver medallist at the World Championships, had to leave a national team training camp in Sognefjell a fortnight ago due to a medical issue.

She felt her body "was not responding well to training" with doctors recommending that she reduce her workload. 

Nilsson, who won nine International Ski Federation (FIS) World Cup events last season to finish fourth in the overall standings, has now returned on an adjusted training programme.

"We have adjusted the training to get my body training ready again," she said. 

"I feel confident about the plan and I am not worried about my shape for the winter. 

"I'm looking forward to an exciting season."

Nilsson, second in the FIS World Cup sprint rankings during 2016-17, will be hoping to star at the Pyeongchang 2018 Winter Olympics in February.

"Stina probably went though a minor infection without noticing it," Sweden's coach Rikard Grip said.

"In combination with the heavy training load, it has affected the way her body reacted to training. 

"Stina has responded well to the easier programme she has had in the past week and we are positive that she will soon be back in great shape. 

"The most important thing now is that she gets some rest so that she can focus on the right things."