Why Girls Need the Gym Through Puberty — And Why Strength Training Should Continue Into Adulthood
Puberty Is a Critical Window, Not a Reason to Stop
Puberty is one of the most important windows in a girl’s life for building confidence, strength, coordination and long-term health. It is also, unfortunately, one of the most common times for girls to step away from sport, PE and structured exercise.
This matters.
During puberty, the body is changing quickly. Height increases, hips widen, body composition changes, periods begin, energy levels can fluctuate and confidence can take a hit. For many girls, movement starts to feel different. What once felt natural can suddenly feel awkward, uncomfortable or embarrassing. Add in social pressure, school stress, changing friendship groups, fear of being judged and a lack of female-focused exercise environments, and it is easy to see why so many girls drop out.
Women in Sport reported that more than one million teenage girls in the UK who once considered themselves “sporty” disengage from sport after primary school, with common reasons including fear of judgement, lack of confidence, school pressure and not feeling safe outside. The World Health Organization has also highlighted that around 85% of adolescent girls globally do not meet the recommended level of physical activity, and that girls’ participation declines throughout adolescence.
Puberty should not be seen as a time to pull back from movement. It should be seen as a time to support girls better, educate them properly and give them an environment where they can keep training with confidence.
Why the Gym Can Be So Powerful for Girls
For girls going through puberty, resistance training is not about lifting heavy for the sake of it, changing how they look, or training like an adult bodybuilder. It is about learning how to move well, getting stronger, building resilience, improving posture, developing confidence and giving girls a place where their body is valued for what it can do, not just how it looks.
A well-coached gym environment teaches girls how to squat, hinge, push, pull, carry, brace, land, jump, decelerate and control their body. These are not just gym skills. They are life skills. They support sport, reduce injury risk, improve physical literacy and help young people feel more capable in their own body.
The old idea that resistance training is unsafe for children or teenagers is outdated. The National Strength and Conditioning Association’s position statement on youth resistance training concluded that properly designed and supervised resistance training can be safe and beneficial for children and adolescents, improving strength, motor skills, performance and confidence while helping young people build positive exercise habits.
Girls do not need to be confident before they start training. In many cases, confidence is built through training. Learning a new exercise, lifting a little more weight, improving balance or moving with better control gives girls clear evidence that they are improving. That is powerful, especially during a stage of life where many girls become more self-conscious about their bodies.
Building Strong Bones for Later Life
Puberty is a key period for bone development. A large proportion of adult bone mass is built during childhood and adolescence, which means the teenage years are not just preparation for school sport or weekend matches; they are preparation for adulthood.
Weight-bearing exercise, jumping, running, landing and resistance training all provide the mechanical loading that bones respond to. A 2024 systematic review and meta-analysis found that exercise interventions significantly improved bone mineral content and bone mineral density in adolescents, particularly around important sites such as the lumbar spine and femoral neck.
This is especially relevant for girls and women because bone health becomes increasingly important later in life. Lower muscle mass, lower strength levels, pregnancy, postnatal changes, perimenopause, menopause and age-related bone loss can all affect long-term physical health.
Building stronger bones and stronger muscles earlier in life gives girls a better foundation to carry into adulthood. It is much easier to build strength, movement skills and confidence early than to try and rebuild everything later after years of inactivity.
Reducing Injury Risk and Supporting Sport
Girls who play sport often need more strength training, not less. As girls grow, changes in limb length, body shape, coordination and strength can temporarily affect how they move. This can influence running mechanics, landing positions, knee control and confidence in contact or change-of-direction situations.
Resistance training can help girls develop stronger hips, hamstrings, glutes, calves, trunk and upper body. These areas are important for sprinting, jumping, landing, changing direction, absorbing force and staying robust through sport.
This is particularly important for sports such as football, netball, hockey, athletics, gymnastics, tennis and dance, where girls are exposed to repeated landing, cutting, acceleration and deceleration. Strength training does not replace sport-specific practice, but it gives the body a better base to tolerate it.
A good youth strength programme should not just be about making girls tired. It should teach them how to move, how to control their body and how to produce and absorb force safely.
The Mental Health and Confidence Link
The benefits of resistance training are not only physical. For many girls, the gym can become a place where they feel capable, independent and in control.
This matters because puberty can be a difficult time emotionally. Body image concerns often increase, confidence can drop and girls may start comparing themselves more to others. Exercise environments can either make this worse or help protect against it.
A positive gym environment should focus on strength, skill, effort and progress rather than appearance. The message should not be “train to look smaller”. It should be “train to feel stronger, move better and trust your body”.
This shift is important. When girls start to see their body as something capable rather than something to constantly judge, their relationship with exercise changes. Training becomes less about punishment and more about self-respect.
Practical Recommendations for Girls Going Through Puberty
The best approach is simple, consistent and well-coached. Most girls do not need complicated programmes. They need the basics done well, in an environment that feels supportive.
A good starting point is two resistance training sessions per week, especially if they are already doing sport or PE. Each session should include lower-body strength, upper-body strength, core control, balance, landing mechanics and some basic conditioning. Exercises such as squats, split squats, hip hinges, step-ups, rows, presses, carries, bridges and controlled jumping or landing drills are all useful when taught properly.
The focus should be on technique first. Load can be added gradually once movement quality is good. Girls should not be rushed into heavy lifting, but they also should not be held back unnecessarily through fear. Strength training should be progressive, age-appropriate and based on the individual.
For girls who are less active or nervous about the gym, even one structured session per week is a positive start. The main goal is to build confidence and consistency. Once training feels normal, frequency and intensity can gradually increase.
Parents should also avoid making exercise conversations about weight, body shape or appearance. Instead, talk about feeling stronger, being more confident, improving sport performance, reducing injury risk, supporting mental health and building habits for life.
The Importance of Continuing Exercise Into Adulthood
The key word is continuation.
Too often, exercise is treated as something girls do when they are young, sporty or trying to change their body. That is the wrong message. Strength training should be seen as a normal part of growing up and a normal part of adult life. It should sit alongside brushing your teeth, eating well, sleeping properly and looking after your mental health.
Girls who learn to train through puberty are more likely to understand their body, respect their body and continue moving when life changes. They are better prepared for sport, exams, university, work, pregnancy, motherhood, menopause and ageing. The exercises might change, the goals might change and the intensity might change, but the habit should remain.
The World Health Organization recommends that children and adolescents average at least 60 minutes per day of moderate-to-vigorous physical activity across the week, with vigorous activity and activities that strengthen muscle and bone included at least three days per week. For adults, the recommendation is 150–300 minutes of moderate aerobic activity per week, or 75–150 minutes of vigorous activity, alongside regular muscle-strengthening activity.
That does not mean every girl or woman needs to live in the gym. It means strength, fitness and movement should remain part of life in some form.
Practical Recommendations for Adult Women
As girls move into adulthood, strength training becomes even more important. Work, family, stress, pregnancy, postnatal recovery, reduced sport participation and busy schedules can all make it harder to stay active. This is exactly why the habit needs to be built early.
For most adult women, two to three resistance training sessions per week is a realistic and effective target. These sessions should prioritise the major movement patterns: squatting, hinging, pushing, pulling, lunging, carrying and core control. This does not need to be complicated. A well-structured 45–60 minute session done consistently will beat a perfect programme that is never followed.
Cardiovascular exercise should also remain part of the week, whether that is walking, running, cycling, swimming, sport, classes or conditioning sessions. The best form of exercise is usually the one someone can keep doing.
Women should also be encouraged to strength train through different stages of life, with appropriate adjustments where needed. During pregnancy, postnatal recovery, perimenopause and menopause, exercise may need to be modified, but it rarely needs to stop completely. In many cases, resistance training becomes even more valuable for maintaining muscle, bone density, metabolic health and confidence.
What Parents, Coaches and Schools Can Do Better
For parents, coaches and schools, the aim should not be to force girls into exercise environments that make them feel uncomfortable. The aim should be to create spaces where girls feel supported, coached properly and allowed to progress at their own pace.
That means focusing on technique before load, encouragement before pressure, long-term development before short-term performance, and health before appearance.
Girls need to see strength training as normal. They need female role models, supportive coaching, sensible progression and environments where they are not made to feel judged. They need to understand that getting stronger is not something to fear. It is something that can help them in sport, in school, in daily life and in adulthood.
The language adults use matters. We should talk less about burning calories and more about building strength. Less about shrinking bodies and more about building confidence. Less about exercise as punishment and more about exercise as a long-term investment.
SPC Girls Youth Group — Starting This September
At SPC, we are starting a girls-only youth group from September, designed to give girls a positive, supportive and well-coached introduction to resistance training.
The group will run on Saturdays from 11am–12pm and will be led by Annie Rolf. Annie brings a brilliant combination of coaching experience, sporting background and understanding of what young girls need to feel confident in a training environment.
The aim of the group is not just to teach girls how to lift weights. It is to help them feel comfortable in the gym, understand their bodies better and build confidence during a stage of life where so much is changing.
Puberty can be confusing. Girls experience changes in body shape, periods, energy levels, coordination, confidence and emotions. For some, these changes can make exercise feel harder or more intimidating. That is why having a girls-only environment matters. It gives them a space where they can ask questions, learn properly and train without feeling judged or uncomfortable.
Alongside resistance training, movement skills and general fitness, we will also include workshops around girls’ and women’s health. These workshops will help educate girls on topics such as puberty, periods, strength training, body confidence, injury prevention, nutrition, recovery and long-term health.
We want this group to be more than just another exercise session. We want it to be a place where girls can learn, train, grow in confidence and understand why strength training is so important through puberty and beyond.
This group is ideal for girls who play sport, girls who want to feel stronger, and girls who may not yet feel confident stepping into a gym environment.
Final Thoughts
Puberty should not be the point where girls drift away from exercise. It should be the point where we teach them how important it is.
The gym is not just for adults. It is not just for athletes. It is not just for people chasing weight loss. For girls, it can be one of the most empowering places they step into — not because it changes who they are, but because it helps them realise what they are capable of.
Done properly, resistance training can help girls through one of the most physically and emotionally challenging stages of growing up. It can keep them connected to sport, improve their self-esteem, support healthy bones and muscles, reduce injury risk and give them tools they can use for the rest of their life.
Girls need to gym through puberty because they deserve to feel strong, capable and confident in their own bodies. And they need to continue exercising into adulthood because strength is not just something we build for now. It is something we carry forward.
References
World Health Organization. WHO guidelines on physical activity and sedentary behaviour. 2020.
Bull, F. C. et al. World Health Organization 2020 guidelines on physical activity and sedentary behaviour. British Journal of Sports Medicine, 2020.
Faigenbaum, A. D. et al. Youth resistance training: updated position statement paper from the National Strength and Conditioning Association. Journal of Strength and Conditioning Research, 2009.
Zhang, W. et al. Effects of exercise on bone mass and bone metabolism in adolescents: a systematic review and meta-analysis. Frontiers in Physiology, 2024.
Women in Sport. Reframing Sport for Teenage Girls: Tackling Teenage Disengagement. 2022.
WHO Europe. 85% of adolescent girls don’t do enough physical activity. 2022.
