Do women get “bulky” lifting heavy weights?

Unless a woman is putting tremendous effort to her weight training regime and diet (more on that below), the answer to this is NO. But I’ve said that enough times through the years to know that most women need a bit more detail before they buy in … so here is the science that explains why women need not fear the 20lb dumbbells.

Women report that they don’t want to “bulk up”, they just want to “tone”. Muscle “tone”, also known as residual muscle tension, is the low level contraction of muscles while at rest. Basically, it is what makes a muscle still feel “firm” when not intentionally being contracted. When a woman wants tone, she usually means that she wants to look leaner and feel firm. These body composition changes come from 2 things: increasing lean muscle mass and decreasing the fat around the muscle. Fat reduction is a big topic for another day … but lets look more closely at what’s required to increase lean muscle mass.

When a muscle is worked to the point of “fatigue” through weight training, tiny micro-tears are created in the muscle fibers. The body responds with a process of repairing these tears and, in doing so, makes the muscles stronger and a little bit bigger; this is called hypertrophy. This process of muscle repair is required for any muscle gains, including “toning”.

The “point of fatigue” part is very important. Too often I see women doing 2 sets of 15 with a weight that only finishes them at about 75% of their maximum (fatique). They are under the impression that this is the strategy for “toning”. This is not correct and these women will see very little changes to their appearance and strength. To have real gains, the final 2-3 reps must be really hard to complete. Fatigue can be reached using lighter weight, but to get there you have to do a lot of reps; which takes time – something few of us have an excess of. Much more efficient is to use a heavier weight so that fewer reps (and time!) is required for the same effect.

Now if you look at serious body builders whose goals are to really “bulk up”, they will take this physiological “muscle repair” response and push it to the absolute max with hours and hours of extremely heavy weight lifting and very strict diets aimed at increasing muscle mass. But if you, like most of us, are not shooting for a “Ms. Universe” title but are simply spending a few hours a week lifting weights for the purpose of some strength and “toning”, your body is not going to respond in the bulky “Arnold” way.

A very important factor that differentiates between men and women’s response to weight lifting is testosterone. Testosterone is a steroid hormone that is found naturally in both men and women – but at way higher levels in men … about 20x more. In addition to other important functions, testosterone is required for muscle building. This means that men who lift weight at the same effort as women will end up with “bulkier” muscles. Now there are some women who do have relationally higher levels of testosterone – these women may find that their body responds to weight lifting a little bit faster and easier.

For the great majority of women, however, lifting heavier weight promotes strength, not size. And strength is GOOD for women! Generally, being physically strong will make all aspects of life easier, from carting groceries to participating in sports and activities. It reduces risk of injuries and major health issues like osteoporosis, cardiovascular disease and diabetes. Strength training also improves neurological response and contributes to a happy, positive mood.

So if all of this hasn’t convinced you to steer clear of the pink dumbbells, I finish with this reminder – increasing your lean muscle mass will help you burn calories. As your lean muscle increases so does your resting metabolism, which means that you will burn more calories all day, even at rest. . At rest, 1 lb of muscle burns about 3 x more calories per day than 1 lb of fat! Do the math on that – it can really add up!

Have fun ladies … happy lifting!