Women and Weights can still be mates

Wednesday, 7:45am at the Bloomsbury fitness studio at UCL: My typical power-HIIT and core class comprises mainly of women, barbells, a set of dumbbells and a step. I often monitor the progress of regular attendees, making sure they are challenging themselves and progressing with small increases in weight and intensity, and often get asked questions such as:

“Is increasing the weight going to make me look bulky?

Is doing this type of strength and resistance training going to help me burn more fat than cardio?

How much weight should I use if I only want to tone up?”

These questions are unsurprising.

We’re all aware that squat racks and benches are predominantly occupied by men, along with clouds of testosterone that may be difficult to step through. And while #strongisthenewsexy has been trending for a while, there is still a lot of uncertainty in the general audience about the true impact and effectiveness of resistance training in women and what biological changes actually occur during this type of training. It’s time to remove this uncertainty; let’s start off by defining resistance training: It is a series of exercises with an external force to work against which can be in the form of free weights, body weight, fixed weight machines, medicine balls, elastic or non-elastic bands and so on.

Not Just About Growing Your Muscles

The majority of women think of strength training from an aesthetic point of view, unaware of the benefits it has on general health and well-being. Muscle makes up about 30% in women, and is extremely responsive to external stimuli such as resistance training¹. It therefore determines the functional ability of an individual. Moreover, muscles work in unity with bone, and the less they feel, the less your bones can maintain themselves. It is well-evidenced that a woman’s risk of osteoporosis is dramatically reduced if she weight trains(2).

The benefits do not end there: resistance training has been shown to have a favourable effect on polycystic ovarian syndrome, as it can create changes in hormones that can improve its symptoms such as insulin insensitivity and weight gain(3). Although women are not unfamiliar with the idea that exercise has multiple benefits on the human body, what is less obvious are the mental and biological benefits of different types of exercise; for example lifting weights compared to aerobic exercise.

A recent study investigating this found striking differences in brain function between individuals who added a component of strength training to their workouts(4,5). Women who strength trained performed better in problem-solving, processing speed, global cognition and memory. Overall, the evidence shows that the benefits of strength training are not just confined to physical changes, but a combination of physical, mental and biological functions. This calls for a change in focus: to really think about achieving better bodily function rather focusing solely on aesthetics. For this, we need to develop an understanding of the biological and physical impact of resistance training based on current evidence.

Tone up the Volume

Resistance training is an extremely broad term, and training outcomes are heavily dependent on the structure your resistance exercise sequence in the form of sets, load, reps, rest and number of exercises. This structure, termed as training volume is ultimately what will allow you to get closer to your goals. This truth about resistance training stems from the fact that it is then possible to target various aspects of functional training including muscular strength, endurance, power and hypertrophy (Box 1) depending on the structure

of your training volume, and also it’s progression. Normally, when women want to ‘tone up’, to fitness instructors, that means hypertrophy. As women, we have evolved to have multiple $genes that are responsible for the proportion of muscle we have, and also that control for muscle size(6). For example, women have a lower percentage of muscle mass to begin with, and also a lower proportion of the type of muscle fibre that is mainly responsible for ‘bulking’, type II.

In the strength and conditioning world, it is well known that using heavy weights with few repetitions develop muscular strength, and lighter weights with many repetitions develop muscular endurance. Interestingly, it has also been found that training till you cannot do another repetition by either of the two methods result in equal amount of hypertrophy(7).

The finding can be attributed to the fact that while training muscular strength, we train type II fibres or fast twitch fibres more, while training endurance we train type I or slow twitch fibres, and training one or the other results in increase in size of those specific fibre types(7). An additional possibility is that as type I fibres tire out, type IIs take over and being more hypertrophic in nature, establish larger gains in muscle(8). And so, in terms of muscle building, you are actually giving yourself the same reaction to grow “bigger”, a key difference is that the average woman has a larger proportion of type I fibres than type II, and fewer type IIs anyway, so it is more difficult for the average woman to bulk up(9,10).

Other key factors that influence this are number of sets you decide to do, and your nutrition of course.

So whether you decide to pick up a couple of kilos or something as heavy as your bodyweight, training to failure results in similar changes in muscle size, but what would differ is the aspect you train (strength, power, endurance). It is thus really important to reconsider your goals, whether that’s improving strength and lean muscle mass, running a marathon or performing better in a sport while thinking about the potential improvements in your everyday function. I hope I have convinced you to explore the versatility that resistance training has to offer, and to pick up the weight you’ve always thought twice about!