Legend says the wives and mothers of Spartan warriors sent their men to battle with the words "come back with your shield, or on it" ringing in their ears. This notion of never retreat, never surrender may have made for a fearsome city-state but two thousand years later it is reckless advice for those looking to improve their personal fitness performance.
There will be days when your muscles aren’t quite as strong. There will be days when your endurance is lagging. There will be days when a little voice warns against pushing too hard.
Blindly ignoring these signals is a bad idea. Only injury and setback await.
Far better to ease off, take a step back and return to fight another day. Your fitness longevity depends on it.