Hot MedFax

Want to know what it means when someone's smiling at you?  According to newswise.com, it depends on what muscle they're using. That's right, muscle.   “When distinguishing among smiles, both scientists and laypeople have tended to focus on true and false smiles. The belief is that if you smile when you’re not happy, the smile is false,” the web site quotes Paula Niedenthal, a psychology professor at the University of Wisconsin–Madison. “But people smile in many different circumstances and during many emotional states. So asserting that only smiles that result from states of happiness are ‘true’ smiles limits our understanding of this important facial expression.” Niedenthal and colleagues from Cardiff University and the University of Glasgow published a set of experiments that seek to expand our understanding of the human smile this week in the journal Psychological Science, showing three distinct, reliably recognized expressions — smiles of reward, affiliation and ...

We've all heard it.  And most believe it.  No pain no gain. But a new study has found, as Gretchen Reynolds reports, that " while it is possible to push through fatigue to reach new levels of physical performance, it is not necessarily wise." She writes that scientists have long been puzzled about just how muscles know that they’re about to run out of steam "and need to convey that message to the brain, which has the job of actually telling the body that now would be a good time to drop off the pace and seek out a bench." Earlier research established that contracting muscles release a number of substances, including lactate, certain acids and adenosine triphosphate, or ATP, a chemical involved in the creation of energy. The levels of each of those substances were shown to rise substantially when muscles were working hard, Reynolds notes. Reynolds goes into much more detail than I will here, but the bottom line is that " the feeling of fatigue in ou...

Trying to bulk up?  Stay away from Vitamin D2. A new study says that, contrary to popular teachings, the vitamin tears up your muscles after heavy weight-lifting. According to newswise.com, the study " showed that taking vitamin D2 supplements decreased levels of vitamin D3 in the body and resulted in higher muscle damage after intense weight lifting." "This is the first time research has shown that vitamin D2 supplementation is associated with higher muscle damage after intense weight lifting, and thus cannot be recommended for athletes,” said Dr. David Nieman (Dr.P.H.), who directed the study, at newswise.com. The study was designed to measure the effect of six weeks of vitamin D2 supplementation in NASCAR pit crew athletes and the effects on exercise-induced muscle damage and delayed onset of muscle soreness. During the double-blind study, one group of athletes consumed 3,800 international units (IU) a day of a plant-based vitamin D2, the Web site reports. ...