Q I'm considering hiring a certified personal trainer to help me begin a resistance training program to help me prepare for my sport.  But I've always been concerned about developing big muscles like a man, or becoming less flexible because of weight lifting.  Should I be concerned about this? A This is a question that I'm asked many times by female clients.  The short answer is probably not.  The vast majority of women will not develop huge muscles from weight training.  This is due in part to a number of physical differences between men and women.  For example, lower testosterone levels in women may have a limiting effect on the amount of hypertrophy or muscle size growth for women.  It has also been reported that the muscle fibers in women are smaller than those for men.  These, and other findings explain why, generally, women will not develop huge muscles from weight training.  Also, with some proper stretching exercises incorporated into your routine, you should be able to maintain, or actually increase your flexibility. The good news is that women can definitely increase their strength through weight training.  Women's muscles react in much the same ways as men's in terms of their potential for developing increases in strength and power from weight training.  So, this type of workout can translate into an increase in the ratio of muscle to body fat, a leaner body, a stronger body, and better performance in your sport and everyday life. As with all forms of exercise, you should consult with your physician or health care professional, before undertaking any of the fitness training discussed in this article.  Any application of the techniques, ideas, and suggestions discussed on this page is at the reader's sole discretion and risk.   LEC Fitness, LLC