Love or hate exercise? It may be in your genes

Whether you get pumped up for gym time or you’d rather crawl back into bed if someone mentions exercise, your genes might be to blame, a new study suggests.Most people receive a mental reward from working out in the form of increased levels of dopamine -- a brain chemical associated with feelings of motivation, pleasure and well-being.But some people apparently don’t get that benefit because of genes that interfere with the release of dopamine, said study lead researcher Rodney Dishm