How do you restrict safe mode?

[Devauzamaki]

I know people do it to test base skills,but sage mode is nature energy,all you have to do is absorb it out of nature. It would make more sense to say the person refuses to use sage mode. Saying its restricted is kinda impossible unless you blow up the planet lol

 

[RaitonOniKairRasengan]

If you stop them concentrating long enough to build it up, easily can stop them from using.

 

[Draphsin]

Restrictions basically mean that the person doesn't have that particular thing, it's removed from their arsenal.

So SM being restricted would take away an SM users ability to gather natural energy altogether, therefore they can't enter it.