Sainz endures toughest physical prep program ever

Carlos Sainz has been in lean and mean mode since initiating his winter physical preparation, enduring a daily regimen imposed by this year's regulation changes.

As professional athletes, drivers typically kick back a bit during the winter break while maintaining their physical condition before getting back into the saddle.

But the 2017 cars are expected to impose huge physical constraints on drivers with the increase of cornering speeds and g-forces.

Like his colleagues, flanked by a personal trainer, Sainz is giving it his all, with efforts centered around endurance, building muscle mass and strengthening the shoulder and neck area.

"Instead of the usual 50 minutes, we now do between 90 and 120 minutes, the same as a grand prix," Sainz revealed.

"Thus, I work out for longer times at around 180-190 beats per minute. I also include boxing and cardio work in those sessions, which all in all means I work my physical endurance way more by doing stuff all the time."

"We work out the neck in two ways," he explained.

"Firstly, we pull and hold weights with it in the gym, which is very similar to what we will do on the track - resisting g-forces, that is - and secondly we are doing specific go-karting, which I do two or three times a week."

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Taking his kart for a spin, Sainz wears a dedicated helmet which includes ballast in specific areas which stress the neck muscles.

"Those weights make my helmet around 1.5 to two kilos [3.3 to 4.4 pounds] heavier, which translates into similar g-forces I'll have to stand in my F1 car."

"That is just one of a complete set of exercises I'm doing to work my neck fitness to the full."

But it will all boil down to February 27 in Barcelona when pre-season formally gets underway, where fitness out of the box will be just as important as a car's performance.

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