Heart attacks are most likely to occur on Mondays. The accepted explanation is that because Monday is the first day of the workweek, people feel more stress on Mondays than on other days. However, research shows that even unemployed retired people are more likely to have heart attacks on Mondays than on other days.
The statement 'Because they associate Monday with work, retired people are more likely to begin large projects on Mondays' most helps to explain the increased likelihood that an unemployed retiree will have a heart attack on a Monday.