What happens during a growth spurt
Peak height velocity is the point of fastest growth - typically around 11–12 years in girls and 13–14 in boys, with wide individual variation. During this period a young athlete can add 8–12cm of height in a year, most of it in the legs and trunk.
That growth happens at the physes, near the ends of the long bones. Muscle and tendon then have to adapt to the new lengths, which takes time. For several months the athlete is effectively operating with tissues that are playing catch-up.
Why that increases injury risk
- Passive tension across the calf-Achilles and quadriceps-patellar chains rises.
- The growth plates receiving that tension are weaker than mature bone-tendon junctions.
- Relative strength drops as body mass increases faster than force production.
- Longer limbs mean higher forces at landing, with less control over them.
- The nervous system's model of limb length lags behind reality, so coordination temporarily suffers.
- Trunk growth outpacing trunk strength contributes to adolescent back pain in extension-heavy sports.
Spotting the window at home
You do not need specialist equipment. Measure standing height once a month, barefoot, at the same time of day, heels against a wall. Plot it. A jump above roughly half a centimetre a month suggests an active growth phase; more than a centimetre a month is a rapid spurt.
Practical markers help too: shoes outgrown within a season, trousers suddenly short, sleeves riding up, a noticeable change in how they move. Coaches often describe a previously smooth athlete looking temporarily awkward.
What to change during a spurt
- Hold weekly training volume steady rather than progressing it.
- Cap the highest-impact elements - sprint distance, jump count, repeated shooting.
- Keep or add strength training; it is protective, and this is the wrong time to drop it.
- Include calf, quadriceps and hip flexibility work, alongside strength rather than instead of it.
- Prioritise landing mechanics and single-leg control in every warm-up.
- Protect sleep and food intake, energy demands rise substantially during rapid growth.
What not to do
Stopping sport during a growth spurt is not protective. It removes the stimulus that builds tissue tolerance, and the athlete returns weaker into the same demands. Equally, pushing through worsening symptoms because 'it's just growth' turns a manageable few weeks into a lost season.
The middle path - steady volume, more strength, close attention to the 24-hour symptom response, is where the evidence sits.
The upside
The growth spurt is also the period of fastest adaptation. Athletes who keep strength and coordination work going through it typically emerge markedly more powerful on the other side, because they are adding force production to a bigger frame.
Handled well, the spurt is a development opportunity as much as a risk window. It just needs to be recognised while it is happening rather than after an injury has already occurred.