The rough sequence
Puberty in girls usually begins between 8 and 13, with the fastest growth in height around 11 to 12 and periods typically starting after that peak. Shape and body composition change alongside it.
Timing varies enormously and normally. In any under-13 squad you will have girls two or three years apart in maturity while sharing a birth year, which explains most of the differences in size and physicality on the pitch.
| Change | Effect on performance |
|---|---|
| Rapid height growth | Coordination dips temporarily, injury risk rises |
| Longer, heavier limbs | Higher forces on landing and cutting |
| Shape and composition change | Power relative to body weight can dip |
| No automatic strength surge | Strength has to be trained deliberately |
| Periods begin | Symptoms may affect some sessions each month |
What changes, and what it means for sport
Why performance can stall
Boys receive a large strength and power boost with puberty as a by-product of hormonal change. Girls grow in height and mass without the same automatic gain, so power relative to body weight can drop for a while.
That is why sprint times and jump heights can plateau or go slightly backwards in a girl who is training as hard as ever. It is a mechanical problem with a training solution, not a sign of lost talent.
What training should look like
- Two strength sessions a week from around 10 or 11, kept up all year.
- Landing, deceleration and change-of-direction work with real coaching feedback.
- Jumping and hopping, valuable for bone as well as power.
- Steady volume through the fastest growth, rather than adding load.
- Simple tests every couple of months so progress is visible during a plateau.
- Food and sleep treated as part of the programme.
Early and late developers
Early developers often dominate at 12 on size alone, and can be left behind later if skills were never developed. Late developers get overlooked, deselected, and frequently quit before the growth that would have made them competitive.
Coaches who select and judge on skill, effort and development rather than current physical dominance keep both groups in the sport.
The confidence and dropout piece
- Explain the dip before it happens, so it is expected rather than personal.
- Sort kit, changing facilities and period provision, these are common exit reasons.
- Talk about periods and fuelling normally.
- Judge the season on development and enjoyment, not results.
- Keep it social, friendships hold teenagers in sport more than performance does.