Unfortunately, many women are reluctant to lift heavy weights through fear that it will make them ‘big’ or ‘bulky’, a myth that has been repeatedly disproven with studies showing women only achieved around half the muscular hypertrophy (growth) as men from resistance training. Instead, women often say they just want to ‘tone’, however, the term ‘tone’ is often misunderstood and isn’t actually a process in itself. In order to achieve a toned look you simply have to lose body fat, whilst increasing muscle mass will also help enhance the ‘toned’ appearance. Such effects were found in a study from 1990 that used heavy resistance training on women and found a decrease in body fat, an increase in lean body mass and no change in thigh girth, meaning the women’s’ thighs stayed the same size but would have looked more toned.
In order to understand gender differences during strength training, we have to first understand what causes muscles to grow. Whilst the process is very complicated it essentially comes down to our levels of muscle protein synthesis (MPS), a process which repairs the muscles that have been trained and causes them to grow. MPS is affected by a lot of things, many exogenous, but a big endogenous factor is testosterone levels, were found to increase MPS by 27% on average. Studies have found that higher testosterone levels correlate with higher MPS levels and thus an increase in muscle mass, therefore, there is a direct link between testosterone levels and getting ‘big’ muscles. This relates to gender differences because of the significant difference in testosterone levels between men and women, with women being found to have as little as 1/15th of the resting testosterone levels of men.
Another interesting finding is the effect of testosterone levels within the normal ranges. It’s been found that strength training does, in fact, induce the release of testosterone, an effect that is helpful for everyone. Studies have found that higher testosterone levels seem to correlate with being leaner, whilst lower testosterone levels correlated with having higher body fat. Furthermore, women not wishing to add significant muscle mass will be happy to hear that research has also shown that any natural increase in testosterone, as seen after resistance training, within the normal levels has no effect on muscle growth.
In conclusion, resistance training, specifically for strength, is a vital part of any fitness programme for both men and women.