“Gone are the days when success depends on how you use your muscle tissues. In this 21st century, your brain cells must work more than your muscle tissues!” PastWorkBrainGoneHard WorkFood For ThoughtIsraelmore AyivorYesterdayCellsMuscles21st CenturyDayWork HardTissuesDaysBrain CellsMuscle21TissueTwenty First CenturyMuscle TissuesPast And GonePast DaysTwenty First Book:The Great Hand Book of Quotes Source: The Great Hand Book of Quotes