Jason Derulo — RISKING HIS NECK … To Stay Jacked

0930_jason_derulo_akmgsi2Question: If you were thiiiiis close to being paralyzed after fracturing your neck in a freak accident in 2011 … and you had to rehab for months to get back to normal … would you risk it all for a killer physique

Answer: ABSOLUTELY … if you”re Jason Derulo.

The “Whatcha Say” singer hit up a park in Sydney, Australia this weekend … and bent over backwards for some kind of a handstand, pushup thing during a topless workout.

As we previously reported, J.D. screwed himself up bad just 2 years ago … breaking his neck while doing tumbling and acrobatics during rehearsals for his tour.

Clearly, the guy feels confident his body is fully healed.