Ah, adolescence—a time of rapid growth, emotional rollercoasters, and, if you're a track and field coach, watching your athletes transform into entirely different beings right before your eyes. One season, they're zipping across the track or soaring over the bar; the next, they’re struggling with coordination, feeling sluggish, or, for some, suddenly unlocking superhuman abilities.

So, what do we need to know and do when coaching athletes through this phase?

The Pre-Puberty Performance Paradox

Until around age 12, boys and girls are pretty much neck-and-neck in terms of performance across sprinting, middle-distance running, jumping, and even throwing events. Strength, speed, and power don’t differ much. But after this? Buckle up, because the divergence begins.

For boys, testosterone kicks in like a turbo boost, increasing muscle mass and power production. This results in an acceleration of performance improvements, especially in sprinting and jumping, peaking around ages 13-14 before gradually slowing down towards 18.

Why does this happen? Biologically, testosterone levels increase significantly in boys post-puberty, leading to a surge in muscle fibre hypertrophy (growth), particularly in type II (fast-twitch) fibres, which are crucial for explosive movements like sprinting and jumping. Additionally, boys experience a higher rate of bone density increase and tendon stiffness, which improves force transfer efficiency—essentially, their bodies become stronger and more mechanically efficient at generating power. Furthermore, red blood cell mass increases, boosting oxygen-carrying capacity and endurance, giving male athletes an advantage in middle-distance and longer events.

For girls, it’s a different story. Growth continues, but with a steady increase in body composition changes and a plateau in muscle mass by ages 15-16. This leads to a gradual decline in relative performance improvements. While gains still happen, they occur at a slower rate than in their male counterparts. Understanding this is key to setting realistic goals and managing expectations for your athletes.

Interested in learning more about female adolescent plateaus? Check out this article here.

Training Windows: Timing is Everything

Each athlete experiences their ‘growth spurt’ at slightly different times, but trends suggest that:

Boys benefit from a strength and power emphasis post-13, as their bodies respond better to explosive training.
Girls may need earlier intervention with neuromuscular training to maintain coordination and reduce injury risk during their growth phase.

The concept of training windows refers to specific periods in an athlete’s development when their body is most responsive to certain types of training. These ‘windows of opportunity’ vary by age and biological maturation, and capitalising on them can significantly impact long-term performance outcomes.

Speed Development Window (Ages 6-13): This is the prime time to develop speed, agility, and overall movement mechanics. Sprint drills, acceleration work, and multi-directional agility exercises should be prioritised before puberty, as neural adaptations occur most efficiently during this period.
Aerobic Capacity Window (Ages 11-16): While endurance can be improved at any age, this window is when aerobic development is particularly receptive. Steady-state running, interval work, and tempo training are most beneficial here.
Strength and Power Window (Ages 13-18 for boys, 11-16 for girls): After puberty, when muscle mass increases, athletes can handle higher training loads. Resistance training, plyometrics, and Olympic lifts become particularly beneficial in this phase, though they should be introduced with proper technique and progression.
Coordination and Technical Skills Window (Ages 8-14): Young athletes should be exposed to a variety of movement patterns, technical drills, and sports-specific mechanics. The ability to refine technical execution is heightened before and during early adolescence.

Simply put: The timing of peak improvements in sprinting (around 12-13 for boys and 11-12 for girls) differs from jumping, which peaks slightly later. This means your training focus should adjust accordingly, ensuring that training is tailored to maximise each athlete's development during these critical windows. Each athlete experiences their ‘growth spurt’ at slightly different times, but trends suggest that:

Boys benefit from a strength and power emphasis post-13, as their bodies respond better to explosive training.
Girls may need earlier intervention with neuromuscular training to maintain coordination and reduce injury risk during their growth phase.

Simply put: The timing of peak improvements in sprinting (around 12-13 for boys and 11-12 for girls) differs from jumping, which peaks slightly later. This means your training focus should adjust accordingly.

Speed vs. Power: Why Jumpers Improve More Than Sprinters

Interestingly, performance progression is twice as high in jumping events compared to running events from ages 11 to 18. Why? Sprinting is largely innate—most kids develop their running mechanics through natural play from an early age. Jumping, however, is a technical skill that requires significant refinement over time.

Speed and power are both essential for track and field athletes, but they develop through different physiological mechanisms. Sprinting relies heavily on fast-twitch muscle fibres (Type II), which generate rapid contractions but fatigue quickly. These fibres are influenced by neuromuscular efficiency, meaning that proper sprint mechanics and explosive strength training can improve their function over time.

Jumping, on the other hand, requires not just fast-twitch muscle activation but also elastic strength, which comes from tendon stiffness and the stretch-shortening cycle (SSC). The SSC allows athletes to store and release energy efficiently during explosive movements like jumping. As athletes mature, their tendon stiffness increases, allowing for greater force application in jumps.

Additionally, stride length and stride frequency are crucial factors in sprint performance. While stride frequency is largely determined by genetics and neural efficiency, stride length is influenced by lower limb strength, hip mobility, and overall coordination—all of which can be improved with targeted training.

So your young long and high jumpers have a higher ceiling for improvement than your sprinters. This should influence how much technical work you incorporate into training versus just raw conditioning. Understanding the biomechanical differences between sprinting and jumping can help coaches design more effective training programs tailored to each athlete’s strengths and developmental stage.

The Gender Gap: When It Opens and What It Means

One of the biggest challenges for female athletes is the psychological impact of hitting a plateau in performance while watching their male counterparts make significant gains. This can be particularly demoralising in a training group where girls who were once outperforming boys now see them surpassing them each season. As coaches, it’s crucial to acknowledge this and foster an environment where progression is measured in personal milestones, technical improvements, and long-term development rather than direct comparisons.

Have the converesation proactively.

From age 11 to 18, the performance gap between boys and girls widens significantly. By the time they reach 18, males outperform females by:

10-12% in running events
~19% in jumping events

This isn’t just a numbers game; it impacts training. For female athletes, coordination and strength development should take centre stage to counteract the physiological changes that might make movement less efficient. For male athletes, managing rapid growth spurts is crucial to preventing injury and ensuring technique isn’t lost in the newfound strength gains.

What This Means for Your Coaching Approach

The key takeaway? Be flexible, be patient, and be proactive.

Expect fluctuations in coordination, particularly during growth spurts. Some athletes may look like they’ve ‘forgotten how to run’—this is normal.
Strength and power training should be tailored based on developmental stage, not just age.
Female athletes may require a greater emphasis on injury prevention, particularly knee and hip stability work.
Monitor growth and make adjustments—if an athlete has a sudden height increase, their stride length, biomechanics, and event performance will shift.

Final Thoughts: Long-Term Development Over Short-Term Gains

It’s tempting to focus on immediate performance improvments, but the reality is that adolescence is about building the foundation for long-term success. A 14-year-old sensation isn’t guaranteed senior-level success, and some of the most promising adult athletes weren’t even qualifying for National Championships in their teens.

So, whether your athletes are thriving or struggling through puberty’s twists and turns, your role is to guide them through it with a steady hand, an adaptable approach, and, of course, a bit of humour. After all, coaching teenagers is as much an art as it is a science.

Now, go forth and coach wisely!

Cracking the Code of Adolescent Athlete Development: What Every Track and Field Coach Should Know