What Happens When I Crack My Knuckles?

What is the actual cause of the sound when you 'crack' your knuckles?

• The skin stretching

• The tendons snapping

• A bubble of gas forming and bursting

• The bones rubbing against each other

Why do scientists believe a bubble forms when you crack your knuckles?

• Because the bones are moving apart

• Due to muscle contraction

• Because of increased blood flow

• Due to skin elasticity

What remains unknown about the sound of knuckle cracking?

• Why it is so loud

• How long it lasts

• Why it is painful

• How it affects skin

How long does it take for the knuckle to return to normal after cracking?

• A few seconds

• A few minutes

• At least half an hour

• A few hours

What is a potential consequence of a lifetime of knuckle cracking?

• Increased flexibility

• Stronger grip strength

• Swollen joints and reduced grip strength

• Improved joint health