For a long time, many people viewed strength training as an activity performed by men for purely aesthetic reasons. Thankfully, strength training is now well-known for providing health benefits and is also popular with women. In addition to aesthetic improvements, strength training is often performed by women to maintain physical function and bone density with age, build strength and endurance, prevent heart disease, and improve athletic performance. Many men strength train to achieve the same goals. Obviously men and women have many varying physical characteristics and their results from strength training can vary as well. In this article, we’ll look at some of the inherent differences and how this can influence how to look at strength training.
The average adult man is stronger than the average adult woman, although it’s an unfair comparison – the average man is 10% taller and weighs about 24 lbs. more . Size and weight correlate with strength, meaning that larger people generally carry more muscle tissue than smaller people. This is true in the case of men versus women. The average man has about 40 to 48 lbs. additional fat-free mass (muscle, bones, water, etc.) than the average woman .
One factor connected to adding muscle tissue is testosterone production. On average, women have half to two-thirds the amount of testosterone that men have. Testosterone does increase as a result of strength training (which helps in the process of of adding lean muscle tissue), and men and women have similar gains in testosterone when factoring in their sizes.
As far as overall strength, women are generally about two-thirds as strong as men. With regard to specific strength differences, women’s lower bodies are proportionally stronger than their upper bodies. Lower body strength in women is about 75% of that found in most men, and the upper body strength ranges in women are 43% to 63% less than men on average. However, when adjusting for the differences in fat-free mass between men and women, overall strength is approximately equal between the two genders. In other words, saying men are stronger than women is similar to saying three-story houses have more rooms than two-story houses.
Finally, the ratio of muscle fiber types is typically equal in men and women. Muscle fibers can be categorized as either fast-twitch or slow-twitch. Fast-twitch fibers produce the most strength, are larger, and fatigue quickly. Slow-twitch fibers have great endurance but provide less strength and size. These fibers vary in their amounts from person to person, dictating what sports they are naturally built for (i.e. great distance runners naturally have a higher-than-average amount of slow-twitch fibers). The average ratio of slow to fast-twitch fibers does not differ between men and women, meaning one sex is not generally built to have more strength or muscle than the other (after accounting for body size).
There are some important inferences from these similarities and differences between men and women. For starters, the vast majority of women should not worry about “bulking up” as a result of strength training. Both men and women typically have amounts of lean muscle tissue that are relative to their overall size. A 5’5” woman growing the same amount of muscle from strength training as a 6’1” man would be an anomaly.
Second, on average women are proportionally on par or are stronger than men when it comes to lower body strength. However, average upper body strength is lower. So, it’s a good idea for many women to make upper body strength exercises an important focus of their exercise program. Keep in mind that muscle function wanes with age, so upper body strength will only get worse if strength training isn’t regularly performed.
Overall, our strength is connected to our muscle size. Men and women contain about the same amount of strength on a pound for pound basis, but men are simply larger (on average). This means you shouldn’t see your own sex as an advantage or hindrance to training. Train consistently with every set fatiguing to the point of “muscle success,” and you’ll see benefit relative to your own body.
By Matt Hedman, President of The Perfect Workout
1. Holloway, J. B., & Baechle, T. R. (1990). Strength training for female athletes. Sports Medicine, 9(4), 216-228.
2. National Strength and Conditioning Association (1989). Position paper on strength training for female athletes. National Strength and Conditioning Association Journal, 11(4), 43–55; 11(5): 29–36.