Ever wonder why pain suddenly appears? Dr. Justin Lin's body capital theory explains it. We all have a "body bank account"; consistent withdrawals (injuries, stress, poor habits) without deposits (sleep, healthy living, good relationships) lead to depletion. Hit zero, and you're at your pain threshold. Go into debt, and pain acts like a debt collector. Invest physically, mentally, and emotionally daily to manage pain and avoid "kneecap-busting" consequences. Heal smarter, not