Strength training in women – part 3

In the previous article, we discussed the difference between male and female muscle fibers, a difference that partially explains why it is not possible for women who train with weights to achieve an excessive increase in muscle mass.

But the most obvious difference, which underlies the mechanisms that regulate male and female adaptation to training, is the hormonal one, particularly testosterone.

In resting conditions, both men and women produce this hormone, but its blood concentration in women is 10 to 20 times lower than that in men. In women, most of this hormone is secreted by the adrenal glands and, to a lesser extent, by the ovaries.

How does the female body respond?

Some women naturally have a higher concentration of testosterone and are at an advantage compared to other women in strength training. However, their levels are still 10-20 times lower than those of men, but slight increases can be observed due to the stress produced by exercise, as well as small increases during the training period.

It has been observed that in women, the modification of muscles, bones, and connective tissues is more closely linked to the production of growth hormone (GH), its variants or aggregates, by the pituitary gland, and growth factors.

It has been noted that, in resting conditions, women have a higher concentration of bioactive growth hormone (growth hormone measured through bioassay) than men, and the changes induced by strength training occur differently. The normal level of growth hormone present in women is also higher compared to that in men.

Why does lean mass increase more easily in some women?

Above-normal increases in lean mass and measurements observed in some women are likely due to several factors:

– higher-than-average levels of testosterone, GH, and other hormones at rest
– enhanced hormonal response to strength training
– lower-than-normal estrogen-to-testosterone ratio
– genetic predisposition for muscle mass development
– ability to perform high-intensity weight training

Men and women in comparison…

In terms of muscle mass differences, women tend to have about 2/3 of the muscle mass of men, with a greater difference in the upper body (about 1/2). Therefore, the fact that men tend to be stronger than women is almost entirely (97%) explained by differences in muscle mass.

This means that if a man and a woman had the same muscle mass, they would have more or less the same strength.

So we can say that most of the differences between men and women, relevant to performance, are not gender-related differences, but rather related to the different body composition.

A woman and a man with similar training and a comparable amount of muscle and fat will likely achieve the same results. This also depends on the type and intensity of training; equipment such as barbells, plates, belts, and knee sleeves can be considered essential.

And what about the role of estrogen?
We’ll tell you in the next episode!

Stay tuned

Sources and bibliography

Here is the translation:
Science and Practice of Strength Training
Vladimir M. Zatsiorsky, William J. Kraemer
Citation: Lundsgaard A-M and Kiens B (2014) Gender differences in skeletal muscle substrate metabolism – molecular mechanisms and insulin sensitivity. Front. Endocrinol. 5:195. doi: 10.3389/fendo.2014.00195