Liam Hemsworth Hikes with His Parents and They're Totally Shredded

Liam Hemsworth gets his good looks and physique from his mama ... and his daddy, clearly!

The youngest Hemsworth bro was out hiking Wednesday with his parents -- looks like they were in the Malibu Hills -- and even though he lovingly referred to them as "oldies" ... their bods are totally camera-ready.

This pic bodes well for Chris and Liam's futures -- their dad, Craig, is completely yoked, and mom Leonie looks like she's ready to run a marathon. Even the family dogs look fit!