Why don’t overweight people have big muscles?  If a person is carrying around 50 lbs. of extra weight in fat, why isn’t that like a super workout which burns lots of calories?    Just lifting the weight out of a chair should build some muscles.  It looks like a certain amount of fat would make you lose fat — so that no one should be obese.

Obviously it doesn’t work like that.  The idea must have occurred to someone besides me, though.  Scientists at Penn State recently published a study they did with rats.  They sewed weights into little rat-sized vests that increased the animals’ weight by 36%.  They tested their muscles five days later and found that certain proteins that deal with muscle strength gain were present.  The rats were getting stronger.

When they just made rats fatter by the same amount, though, there was no corresponding gain in muscle strength and the proteins weren’t there.  It was as if the fat rats’ muscles couldn’t come to terms with the weight of the animal and didn’t respond properly.

So we know that lifting an arm that has five pounds of fat on it is not the same as lifting a five-pound dumbbell.  Scientists don’t know why — possibly because the fat cells are active little critters and send out lots of chemical messages. Some of those messages may be messing with the way muscles respond to weight.

Dr. Schilder, who conducted the study, said they haven’t figured out yet how this finding will help overweight people.  He suggests, though, that it is just harder for overweight people to move around because their weight is too much for their muscles  — and the muscles don’t grow bigger to handle to it.  He suggested that maybe obese people should be encouraged to do easier, less stressful exercise until they have lost more of the weight.

I don’t know if that helps much — but it does answer a question I’ve wondered about.  Fat doesn’t give you a workout and doesn’t make you have stronger muscles.

Eating to live and living for Christ,

Susan Jordan Brown