For Women, Moderate Exercise Might Be Best
Women need to exercise for longer periods at a lower intensity in order to optimize fitness
The typical clichés around exercise are that his idea of getting in shape is pumping iron, while she’d rather pull out the yoga mat. These are indeed stereotypes and there are plenty of women who rave about their latest triathlon and many men who are amazing yogis. However, there are real physiological differences between the sexes that may cause different responses to exercise.
A most substantial contributing factor to these differences depends on something called “muscle fiber type” and how our sex hormones affect it.
There are two types of muscle fibers: Type I fibers, which are great for long, sustained activity; and Type II fibers, which are well-suited for shorter, intense activity. Men possess a higher percentage of Type II fibers which, when combined with higher testosterone levels, makes them excel at “explosive performance,” or short, intense bursts of effort, like sprinting or high-intensity interval training (HIIT).
Women, on the other hand, tend to have a higher proportion of Type I muscle fibers, as well as greater capillary density. This combo allows us to circulate more blood throughout our muscle tissue, and to use our glucose for sustained energy. In addition, our fat deposits are more easily broken down and converted into energy than a man’s, allowing us to go longer, stronger. This makes us better at endurance training. Or to put it simply, women need to exercise for longer periods at lower intensity in order to boost metabolism and optimize aerobic fitness.
This is not to say that women should lift lighter dumbbells or ditch the chin-ups. Obviously, there are plenty of women who can do all of that and much more.
In the exercise world, low-to-moderate intensity exercise is anything that ups your heart rate, making you sweat lightly rather than profusely. At this rate, you can carry on a conversation, albeit a little breathily, but you couldn’t belt out a tune if you tried. In comparison, during high-intensity exercise such as a spin class, one can get out a few words here and there, but not carry on a full conversation.
This is not to say that women should lift lighter dumbbells or ditch the chin-ups. Obviously, there are plenty of women who can do all of that and much more. But as a rule of thumb, both the American College of Sports Medicine and the American Heart Health Association recommend exercising three to five days a week, then adjust the duration of the workout based on your age and overall health, including your fitness level, personal goals, risks, and medications. Age and menopausal status are big factors to consider, whether you’re adjusting your current routine or starting a new one.
Several studies have shown that low-to-moderate intensity exercise in these amounts optimizes metabolic performance in women, especially when sustained over time. The workouts simultaneously strike a delicate balance between glucose and fat utilization, while at the same time boosting hormonal levels. Interestingly, in some studies, tweaking one’s activity to these specs produced a hormonal improvement so pronounced that it alone dramatically decreased both the number and severity of menopausal hot flashes. In one study of 3,500 women, those who engaged in moderate-intensity exercise for a minimum of 30 minutes a few times a week, were 28% less likely to have severe hot flashes than those who exercised less. Active women were also 17% less likely to feel sad or depressed while at the same time resisting weight gain or risking obesity.
Moderate exercise can also have broader implications for overall health: While occasional, high-intensity exercise can increase inflammation, continued, regular exercise turns it down instead, increasing your defenses against a variety of diseases.
I’ve heard it said that the modern, urban woman here in the States has two modes: sitting or spinning — with little in between! As it turns out, your brain actually prefers a gentler, more everyday variety of movement, and the slow, steady burn it delivers. This fact reiterates that, for women in particular, it’s not about intensity as much as frequency and consistency.
I encourage women to experiment with everyday movement as an integral part of their overall well-being, rather than fixating on time spent inside a gym. If you feel like your life leaves you no time for things like walking to the store or taking the stairs instead of the elevator, it’s time to step back and see what can be done. Strangely, the stress and fatigue we struggle with in modern life typically have more to do with what we aren’t doing, rather than doing too much.