New Exercise Guidelines & Reactions to Them

I recently became aware of the American College of Sports Medicine and the American Heart Association’s new recommendations for minimal exercise (http://www.acsm.org/AM/Template.cfm?Section=Home_Page&TEMPLATE=/CM/HTMLDisplay.cfm&CONTENTID=7764 ).

They are:
“Guidelines for healthy adults under age 65
Basic recommendations from ACSM and AHA:
Do moderately intense cardio 30 minutes a day, five days a week
Or
Do vigorously intense cardio 20 minutes a day, 3 days a week
And
Do eight to 10 strength-training exercises, eight to 12 repetitions of each exercise, twice a week.

Moderate-intensity physical activity means working hard enough to raise your heart rate and break a sweat, yet still being able to carry on a conversation. It should be noted that to lose weight or maintain weight loss, 60 to 90 minutes of physical activity may be necessary. The 30-minute recommendation is for the average healthy adult to maintain health and reduce the risk for chronic disease.”

I discussed these recommendations with each of my Personal Training clients and emailed them to my friends and family. I was surprised at the response from friends. They said things like, “O.k. so I’m a slug. Thanks for making me feel out of shape!” “This is perhaps the most depressing news I have read since... Prop 8 passed? McCain pulled ahead in some polls? Something bad, anyway!!” “That's a LOT of exercise just to maintain a healthy fitness level. Wow!” Those were the first responses. Then I received a couple generic replies, like, “thanks for sending this along.” I eventually received only two positive responses to this objective information sharing!

Why would people react negatively to general health information? Why would it make people feel badly rather than inspire them?