You might not think of too much cash as a source of pain, but a fat wallet can trigger piriformis syndrome. The condition can affect men who wear their wallet in the back pocket of their pants. This puts chronic pressure on the piriformis muscle and can aggravate the sciatic nerve over time. You can avoid this problem by keeping your wallet in a front pocket or jacket pocket.
You can strain or tear one or more of your hip flexors when you make sudden movements such as changing directions while running or kicking. Sports and athletic activities where this is likely to occur include running, football, soccer, martial arts, dancing, and hockey. In everyday life, you can strain a hip flexor when you slip and fall, for example.