How do I fix my poor posture?

In general, strength training is going to help posture more than anything else. Getting strong all over and addressing any mobility issues tends to solve most postural problems over time. However, be realistic with yourself. You’re not going to undo a lifetime of poor posture and movement by only addressing specific problems once a week for 15 minutes. It’s take dedicated effort and vigilance to correct the root cause. Also, be willing to accept the fact that some issues just can’t or won’t be fixed by a few simple stretches or exercises.

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For posts, questions, and further advice, check out /r/posture