Keeping Girls in the Game: Rethinking Training for Girls in Puberty
How education, and adjustments to training and expectations during puberty can help girls stay in sport, thrive long-term, and unlock their full potential.
An article written by Sophie Herzog, Øyvind Sandbakk, Trond Nystad and Rune Talsnes
1. The Unseen Struggle
At 12 years old, Emma felt fast, strong, and in control of her body. She loved the feeling of pushing herself up the final hill, outpacing the boys in training, flying over the snow with ease. But by 14, something had shifted. Her body changed, she felt heavy, her stride less fluid. She tried hard, pushed herself a lot in training but didn’t get any faster. Her performances plateaued despite all her efforts – she was frustrated, lost her confidence and the joy of sport disappeared.
Emma’s experience isn’t unique. Across sports, many girls encounter a similar dip in performance during puberty - a dip which is biologically determined but is nevertheless very individual and must not be misunderstood from a performance perspective. Unfortunately, just as most girls enter this phase of intense physical and emotional transformation, expectations in sport often escalate - without the right support, many girls begin to question their future in sport altogether.
Coaches, parents and even the athletes are often ill-prepared to tackle puberty, and face the changes with confusion and concern. Unpreparedness is a paradox, as the human body has not changed dramatically over the last few thousand years. Puberty has always been part of growing up. We know it will most likely bring a dip in young female athlete’s performance, cause emotional turbulence, and bodily changes that impact training and results. So why is the sports world still underprepared and struggling to deal with this important stage of life?
The answer is simple: a lack of education and awareness. If we truly want to support girls, we must do better at preparing them, their parents, and their coaches for what lies ahead. Puberty isn’t a crisis. It’s a biological phase. And with the right preparation, knowledge and support, it can be tackled without fear or frustration, rather with foresight, communication, support and appropriate training strategies. Puberty isn't the end of progress - it's the beginning of a self-exploratory phase on a long-term development journey.
2. What Happens to the Female Body During Puberty?
Puberty is a biological turning point, with some unique challenges, especially for girls. It typically begins between the ages of 8 and 13, triggered by increased hormone production from the brain's hypothalamus and pituitary gland. Estrogen plays a central role, influencing the development of secondary sex characteristics such as breasts and hips, initiating menstruation, and contributing to a shift in body composition.
While these changes are natural and necessary, they also affect how girls move, recover, and respond to training. Increased fat mass, particularly around the hips and thighs, alters biomechanics. Increased body mass and the corresponding shift in the center of mass leads to coordination challenges, which require re-learning of movement patterns that once felt intuitive.
This is further complicated by large individual differences. Two 14-year-old girls can vary 4-5 years in biological maturity yet often train under identical plans and expectations.
Importantly, this phase often marks a divergence between boys and girls in performance. While the physical changes in boys are predominantly performance enhancing, for example through gained muscle mass and aerobic capacity from testosterone's anabolic effects, girls mostly experience stagnation or even decline in strength-to-weight ratios.
3. Why the Performance Curve Isn’t Linear
Standard physical test results show a clear pattern: boys often continue to improve steadily from childhood through adolescence. Girls tend to follow a similar trajectory until age 13 or 14, at which point many hit a plateau, which for some, may last for years.
Research in endurance and strength sports shows that while boys may improve their performance significantly between ages 12 and 18, girls often improve only half as much in the same period. This can lead to discouragement, unhealthy and counterproductive behavior such as extreme dieting, and ultimately dropout.
But there's another narrative behind that is worth telling: many elite female athletes don't reach their peak performance state until their late 20s or early 30s - and in some sports, even later.
This perspective invites a crucial shift: we need to change our expectations and be more patient with female athletes. Too often, societal pressure suggests that women must “grow up” faster, settle into a career, pursue education, or start a family before their athletic potential is matured. These cultural narratives not only place unfair time constraints on women, but they also prevent us from seeing higher female participation rates in sports.
The takeaway? Puberty isn't a ceiling - it's a complex detour. If we accept that a girl’s development follows a different/slower trajectory, we can begin designing systems that help them stay on the course and become incredibly resilient long-term performers. It is not enough to talk about this challenge; we need leaders and coaches in sport who are willing to take responsibility to ensure that girls get equal access to a functional development pathway as boys. More research is needed to ensure that we develop strategies and systems to give all young women an opportunity to reach their athletic potential.
4. Training Smarter Through Transition
What can we do to support girls through this phase? The answer lies in adapting our training philosophies to meet athletes where they are - biologically, emotionally, physically and technically.
Key strategies include:
Shift the focus from high load to skill and fun. As biomechanics change, so should technique. Relearning motor patterns, adjusting balance and timing, and refining skills can restore a sense of mastery. Training less is not necessarily the answer, but changing the load, focus and goals are.
Introduce strength training early and progressively. Girls benefit from strength training not just for performance, but to protect against injury, especially to the knees and lower limbs. Start with bodyweight, coordination-based exercises and progress gradually with proper technique. When the technique is mastered, girls can benefit from focus on strength training to develop their muscle mass and ability to produce power. Therefore, girls can (and should) lift heavy weights!
Tailor load and recovery. Monitor perceived exertion, sleep, mood, and energy availability. Keep an eye on early signs of overtraining or under-fueling, both of which are more likely during puberty.
Track the menstrual cycle. Hormonal fluctuations and associated issues may impact performance, coordination, mood and energy. The same applies to use and side-effects of the various hormonal contraceptives. Therefore, tracking symptoms and responses can inform individual adjustments in training.
Teach self-regulation. Help athletes learn to understand themselves and let them adjust intensity based on internal cues, not just external/objective metrics.
Above all, recognize that physical development is not a race. Some athletes will surge ahead early; others will come into their own later. Both paths are valid – but unfortunately, many talent development systems and team selection criteria do not make room for the “late bloomers”. Too often, early physical maturity is mistaken for talent/long-term potential, leading to missed opportunities for those who are on slower growth- and development trajectories. So, if we want to nurture resilient, high-performing athletes over time, we must design systems that “raise the tides for all boats”.
5. Creating Safe, Supportive Environments
Many girls quit sport not because they don't love it, but because they stop feeling competent, seen, or supported. Puberty can introduce body image concerns, self-consciousness issues, and performance anxiety.
In this sensitive phase, it’s also critical that no false conclusions or judgements are made – for instance about body appearance, motivation or attitude. A drop in enthusiasm or physical performance doesn’t necessarily reflect a lack of interest or effort. Often, young athletes themselves are confused and unsettled by the changes happening within their bodies and minds.
Coaches and teams play a crucial role in either reinforcing these insecurities, or by providing a safe and supportive environment which guides the athletes through these transitions.
Coaches can help by:
Preparing the girls and their parents for how puberty may change the body and how it influences training and performance.
Building trust and fostering open conversations about the body, development, and expectations.
Normalizing puberty as a shared experience, not a taboo or liability.
Shifting focus from short-term results to long-term progress.
Celebrating enjoyment, learning, effort, consistency, and adaptation.
Ensuring girls feel valued for who they are, not just how they perform.
The environment matters as much as the training plan. Girls who feel safe, understood, and empowered are more likely to stay engaged and reach their potential.
6. Practical Guidelines for Coaches and Clubs
To support girls through puberty and beyond, we recommend:
Actively recruit female coaches and leaders
Vary endurance training: terrain, movement forms, and intensity
Emphasize skill development and technical learning
Introduce strength progressively, in line with body changes
Track menstrual health (including side effects) to tailor training
Individualize training loads based on maturity, not just age
Create positive, fun and inclusive training cultures
Focus on process goals over competition results
Long-term athletic development requires patience, perspective, and care. When coaches and systems adapt, athletes don’t just stay in sport – they can build an athletic identity for life.
We need more women in sports, in leadership, science, research and coaching. In Norway, only about 30 % of competitive skiers are women – why is this still the case? In 2025, one would expect participation and representation in sport to be 50/50. What can be done to ensure participation equality in sports?
“We have to address the pink elephant in the room.”
We must focus on ensuring that as many girls and women as possible stay in sport, for as long as possible. That requires structural change, cultural awareness and education! We need to challenge the systems – team cultures, schools, federations, governments – that silently uphold these gendered timelines, and build a world that offers equal time, space and opportunity to everyone, regardless of gender.
7. A Final Thought
The focus should not be that girls underperform during puberty. There should be an understanding that their transformation into a woman is part of their long-term development. What this means in the short-term, from a performance perspective, is a complex and often lengthy recalibration. But, with the right support, girls will emerge as stronger, more confident and resilient women.
At MYRA, we aim to be part of that journey - through education, guidance, and human-centered performance systems that embrace the whole athlete.
