Fernando Alonso says he is currently in "energy-saving mode" as he juggles duties in both Formula 1 and the FIA World Endurance Championship over the next two months to further his bid to win the 'triple crown of motorsport'.

Alonso will make his WEC debut for Toyota in this weekend's 6 Hours of Spa-Francorchamps, forming part of a relentless schedule that will see him be on-track for nine of the next 10 weekends that also includes six F1 races and the 24 Hours of Le Mans.

Alonso is chasing a victory at Le Mans to add to his brace of Monaco Grand Prix wins, with the Indianapolis 500 forming the third part of the 'triple crown', a feat only achieved once before in motorsport history by Graham Hill.

Asked by Crash.net in Azerbaijan how he was adapting to the challenge of balancing two world championship series and the resulting schedule, Alonso explained how he is being more measured in his approach to training given the amount of racing he has coming up.

"I’m in energy saving mode everyday! Because I know that it counts," Alonso said.

"I woke up this morning, I planned to go to the gym and have a little bit of exercise. I woke up, I was not feeling 100 percent, I was 90. So today I did nothing, I stayed a little bit more in bed. I will go early to sleep again today.

"You try to think two weeks ahead, the energy you will need in two weeks’ time or something like that. It’s not a short-term preparation. It’s a long-term preparation.

"I need to be 100 percent on Sunday, 100 percent the Sunday after that in Spain, 100 percent at Le Mans. It’s definitely a very tight calculation of the training programme and how you fly, how you rest, which planes you take, what food you eat.

"You try to always be on the average level 99 percent, and not be picky this year."

Alonso will race alongside Sebastien Buemi and Kazuki Nakajima at Toyota for the full WEC 'super season' as the Japanese manufacturer looks to defeat the rival privateer LMP1 teams in the championship's premier class.

"I’m as prepared as I can be," Alonso said. "Obviously [Spa] will be my first ever World Endurance Championship experience. It’s quite busy now in the next couple of weeks.

"I'm quite looking forward, it will be a new experience, and hopefully a good one."