May 20, 2026 //
Rob Anderson //
Gym News //
6 min read
If your child complains of lower back pain after a heavy training session or a weekend match, it is easy to brush it off as simple muscle ache. However, persistent low back pain in young athletes is often a sign of something that requires a bit more attention.
The most common source of low back pain in youth athletes is a lumbar bone stress injury. While this sounds alarming, it is a highly manageable condition if caught early and treated with the right approach.
In this post, we will explore what causes a lumbar bone stress injury, the warning signs to look out for, and how to guide your child safely back to the sport they love.
What is a Lumbar Bone Stress Injury?
During rapid growth spurts, a small part of the vertebra (the back bone) called the pars elongates. As it stretches, it temporarily becomes thinner and weaker. Because this bone does not fully mature until around the age of 23, it is much more susceptible to injury in young athletes than in adults.
When a young athlete suddenly increases activities that involve repetitive arching and rotation of the lower back, such as kicking a football, throwing a rugby ball, or fast bowling in cricket, the load can exceed the capacity of this immature bone.
To protect itself, the body tries to lay down new bone. However, this process takes several weeks. During this window, the bone is vulnerable. When the current capacity of the bone is exceeded, a “bone bruise” develops.
If the athlete rests, this bruise is quickly reversible. But if they push through the pain and continue playing, that bruise can develop into a hairline fracture, taking many months to heal.
Who is Most at Risk?
Any young athlete aged 8 to 23 who is involved in repetitive kicking, overhead sports, or sports that involve excessive arching of the lower back is at risk.
The risk is significantly higher during the rapid growth spurts of puberty, as the bone is actively changing shape and density.
The 4 Warning Signs to Watch For
If your child develops any of the following symptoms for more than one week, you should assume they have a bone stress injury until proven otherwise:
Opposite Side Pain: Low back pain in the opposite side to the arm or leg they throw or kick with.
Activity Related: Pain that gets worse during activity and settles when they rest.
Movement Triggers: Pain that is noticeably worse when arching backwards, throwing, bowling, running, jumping, or kicking.
Spreading Pain: Pain that spreads across both sides of the back or radiates down into the legs. If this happens, they MUST be checked by a health professional before playing again.
Can They Just Play Through the Pain?
The short answer is no.
To prevent a simple bone bruise from progressing into a stress fracture, your child must stop all aggravating activities as soon as they experience persistent low back pain. Stop ALL activities for at least 2 weeks to let the bone adapt and get stronger.
Crucially, even if the pain settles in a few days, this is NOT an indicator that the bone has healed. It is important to still avoid activities that might bruise the bone further for the full two weeks.
Continuing to play sport with low back pain will likely cause the injury to progress, meaning they will be out of action for much longer. They need to completely avoid high-impact activities like running and jumping, as well as repetitive extension or rotation of the back.
This means no school PE, no swimming, no gym or resistance training, and no organised sports.
However, they do not have to do nothing. They can cycle on a static bike to keep fit, provided it is completely pain-free.
Recovery Essentials: Sleep and Nutrition
Healing a bone stress injury requires a lot of energy. If your child does not eat enough to support both their growth and their activity levels, the body will not prioritise bone repair.
To build stronger bones and muscles, they need a balanced diet with adequate protein, vitamins, and fibre. Low iron or Vitamin D deficiency can also contribute to bone stress injuries, so it is worth asking your doctor to check their levels.
Equally important is sleep. High-quality sleep is when the body performs vital repairs, builds stronger tissues, and reinforces the skeletal system. Ensure they are getting plenty of early nights, especially during growth spurts.
How to Safely Return to Sport
It is important not to return to sport immediately after the low back pain has settled, as the bone can take 3 to 6 months to heal depending on the severity of the injury.
Although your child needs to rest completely from sport, you can start strength exercises immediately…but ONLY under the supervision of a youth athlete trained healthcare professional. As these injuries are rare in adults, many healthcare professionals are not familiar with children’s injuries. Your child will be taken through a progression of exercises to strengthen not just their back, but their leg, hip, and abdominal muscles.
When it is time to return to play, it is important to gradually build back up the volume and intensity of sport again, and not rush straight back to what they were doing before the injury. Add one new activity in every other day so you can assess whether there is any adverse reaction.
Initially, your child should avoid any extra high-impact activities and repetitive activities such as bowling, long-range kicks or throws, sprinting, and tackling in rugby. Avoid doing these high-intensity type activities on back-to-back days in the early stages of return to play. As they start to add these types of activity back in, keep the intensity low, for example, doing kicks, bowling, or throwing at 50 percent effort and only over short distances.
Before returning to activities like bowling or serving, it is also important to get their action checked by a qualified coach, in case technique was a contributing factor.
Is Your Child at Risk?
Injuries often occur when a rapid spike in training volume meets a body that is fatigued or growing. By monitoring their workload, you can help prevent these injuries before they happen.
Click here to get yourr free Peak Performance Profile — a quick tool to help you check whether your child’s current training load is putting them at risk.
