Women must increases their protein intake and workout with weights (intensely) or inevitably succumb to the debilitating effects of age-related muscle loss. And, even with such increases in protein intake, women might not be capable of utilizing the protein as well as men.

Keeping in good shape is more difficult for older women than men because it's harder for women to replace muscle that's lost naturally as they age, say U.S. and British researchers.

The study of 29 healthy women and men, aged 65 to 80, found that women were less able to use protein to build muscle mass -- a key difference in the way women's and men's bodies react to food. This may be due to menopause-related hormone changes in women, said the researchers from the Washington University School of Medicine in St. Louis and The University of Nottingham. One possible culprit is estrogen, which is known to be needed to maintain bone mass.

Rather than eating more, older people should focus on eating a higher proportion of protein in their everyday diet. In conjunction with resistance exercise, this should help to reduce the loss of muscle mass over time.

Come on ladies, don't just workout hard - workout smart and lift your way to a healthier body!