Women Need Strength for Life

Research shows that lighter weights and higher reps can build muscle, but it’s important that we prioritize strength and power.

Anyone who follows me knows that I tell women they need to prioritize strength training in their workouts and that they need to include days where they lift heavy sh*t. So some women have reached out to me, confused about recent headlines regarding a study showing that for older women wanting to build muscle, higher reps and lower weight may be the way to go. Full disclosure, this is not new news, it is well documented in older untrained women, that hypertrophy training (higher reps, lower weight) does increase lean mass; and younger untrained women can gain strength with higher or lower reps by training each session to failure.

So I thought this would be a good time to talk about hypertrophy and power. Though the two are related, they’re not the same. First, a fundamental relationship exists between strength and power, which dictates that an individual cannot possess a high level of power without first being relatively strong. Thus, enhancing and maintaining maximal strength is essential when considering the long-term development of power. You can build strength and power without a lot of gains in muscle size. You can also increase muscle size (aka hypertrophy) without maximizing your strength and power. But the critical factor here is how we consider our loading. It is known that maximal strength gains come from the use of heavy loads, with muscle hypertrophy gains achievable across all spectrums of loads. I’d contend that with age, we’d like to build and maintain both as best we can, but we most definitely want to stay strong.

In this particular study, the researchers compared the muscle-building effect of 12 weeks of strength training (eight exercises, three sets, three non-consecutive days a week) on a group of 101 older (60+) women. One group performed the workouts lifting moderate weights for 8 to 12 repetitions (generally used for hypertrophy); the other group lifted lighter weights for 10 to 15 repetitions (generally used for muscle endurance); with not much difference between total loads lifted across groups. What is interesting is that true heavy-loads were not considered in the design, nor was working to failure; two pivotal training paradigms for comparing strength to hypertrophy. 

In the end, they found greater muscle growth in the group training with 10 to 15 RM loads than the group training with 8 to 12 RM loads. Notably, they also found that the group training for lower reps gained more strength, which is in line with most research. The researchers noted this could be beneficial for older adults who may be more prone to pain and injury with higher loads. They also noted that theoretically, specific to hypertrophy/increasing total lean mass, older women may have less to gain from lifting heavy because age-related muscle loss mostly occurs in fast-twitch type II fibers and women in general have fewer fast-twitch fibers to start than men, so they may respond better to higher repetition training, which favors slow-twitch, type I muscle fibers. 

Women Need Strength 

To be clear, it’s interesting to see the comparison between traditional hypertrophy and endurance rep ranges in an older, untrained population. Those results are not necessarily applicable in the same way to an active population of older women, or women in general, however. I also still encourage women to get as strong as they can, because though there are metabolic benefits to increased muscle mass, such as more glucose uptake, which this study also found (the group doing the higher rep ranges had greater blood sugar reductions), your athletic performance and ultimately your independence in old age depends on staying strong. 

With age and menopause, strength and power are the first things to go. So, I wouldn’t want to put on lean mass without also going for a strength boost, especially considering that strength is a central nervous system improvement, so it helps with neural pathways, important for improving cognitive function as we age. Heavy lifting is also good for improving fat-burning metabolism, building bones, and maintaining your cardiovascular health, all things that menopausal-aged women especially need. Plus, as mentioned, women generally have a lower proportion of type II (i.e. fast power-producing) muscle fibers than men. So hitting the weights to build and maintain as much strength, power, and force is important, especially postmenopause and with age.

Speaking of power, active women need that, too! Power is the ability to produce a high amount of force over a short period of time. To be powerful, you need to be strong. That means resistance training for strength (i.e., lift heavy) and adding some explosive elements like plyometrics. 

In the end, women can certainly build some muscle doing higher repetitions with lower weights in moves like arm curls and leg extensions (which were a couple of the exercises used in the study). But for optimal performance and independence with age, they should prioritize building strength with heavier weights and lower reps (i.e., 3 to 5 sets of 6 or fewer reps), which are best done on “big lifts” like deadlifts, squats, lunges, and other Olympic lifts that spread the force out among your major muscles, connective tissues, and joints.