Overstraining is the enemy of accomplishment. Calm strength that arises from a deep and inexhaustible source is what brings success.
This really comes down to our lack of knowledge of what constitutes true strength in life. All too often we see people "overstraining" themselves- wasting effort, time, and energy trying to do something or control someone or something- because they feel that strength is defined by how much effort is exerted. But strength is not a measure of force or control, nor is it a measure of how well we can absorb the hurt from others; strength is our ability to hold on to our internal peace, serenity, joy, compassion, mercy, and love in the midst of difficulties and failures, uncertainty and discord.
When we are able to handle difficult situations in authentic ways- remaining completely ourselves and not worrying about what others think or say about us- we forego overstraining and overexerting ourselves in harmful and unproductive ways. No longer do we need to raise our voice, curse, or threaten others, for we know that real strength is seeing the situation for what it is and determining a healthy and appropriate response!