A Strength check can model any attempt to lift, push, pull, or break something, to force your body through a space, or to otherwise apply brute force to a situation. The Athletics skill applies to some Strength checks.
Athletics. You might make a Strength (Athletics) check in difficult situations encountered while climbing, jumping, or swimming. Here are examples:
• You attempt to climb a sheer or slippery cliff, avoid hazards while scaling a wall, or cling to a surface while something is trying to knock you off.
• You try to jump an unusually long distance or pull off a stunt midjump.
• You struggle to swim or stay afloat in treacherous currents, storm-tossed waves, or areas of thick seaweed. Or another creature tries to push or pull you underwater or otherwise interfere with your swimming.
Other Strength Checks. The DM might call for a Strength check when you try to accomplish one of these tasks:
• Force open a stuck, locked, or barred door
• Break free of bonds
• Push through a tunnel that is too small
• Hang on to a wagon while being dragged
• Tip over a statue
• Keep a boulder from rolling